American Samoa & the Pacific Remote Islands

Back to Honolulu

2010-04-30T13:56:00.002-10:00

The Hi'ialakai returned safely to port in Honolulu on Sunday, April 24 at 0800 bringing a very successful completion to HA1001, the 2010 Pacific RAMP expedition to Johnston Atoll, the Phoenix Islands, American Samoa, and the Line Islands. All told, we had the participation of 44 scientists from eight different research institutions and local and regional management organizations. We visited 13 islands, reefs, or banks and were once again amazed by the diversity of life found beneath the waves.

In the days since the ship returned to port we have been offloading equipment and getting everything back to its rightful place, ready for our next expedition to the Northwestern Hawaiian Islands in September of 2010. We want to thank everyone who followed along with our expedition and especially those of you who wrote in with your questions and comments. We hope that we have been able to answer most of them and look forward to hearing from you again on future expeditions.

With that, we will sign off for now. As the Northwestern Hawaiian Islands expedition begins, we will host a new blog and will post the address both here and on the CRED FaceBook page where you can follow-along with all of the most up-to-date information on our program.

Perspectives Of Underwater Flight: Towed-Diver Surveys Around The Line Islands

2010-04-22T18:14:00.016-10:00

By Jake Asher and Molly Timmers

Towed-diver Kevin Lino surveys the fish of Jarvis Island

How can scientists get a better sense of what’s living on the bottom or swimming above coral reefs on an island-wide scale? Detailed surveys examining benthic and fish assemblages at specific sites are one way; however, if you're interested in a fast, effective, and extensive method for assessing and monitoring coral reef health over a large spatial scale, towed-diver surveys are for you.

The towed-diver survey methodology is a unique and integrated data collection method for mesoscale assessment of benthic coral reef habitats. The method utilizes SCUBA divers pulled behind a small boat at depth, covering enormous areas of terrain each day, sometimes surveying close to 18 hectares (18 kilometers x 10 meter survey swath). Multiply that out over a 30-day cruise and you can imagine what the towed-diver team sees!

Towed-diver forward-facing view; top panel; Typical photograph from the benthic towed-diver.

What’s on a towed-diver board? Benthic divers have a bottom-mounted camera that collects still photographs of the benthic habitat every 15 seconds, while fish divers have a video camera that records forward-facing video for the duration of the 50-minute survey. Temperature and depth are recorded every 5 seconds throughout the survey (cylinder on the left side). Gauges/timers tell the diver how long the divers have been down for, how deep they are, and sound a 5-minute alarm when each survey segment is completed. Finally, both benthic and fish observations are tallied on the datasheet located on the right-hand side of the board.

Towed-divers typically fly around the entire forereef perimeter of the smaller islands, and stagger their surveys along larger ones. In some cases, divers also survey backreef or lagoon habitats (e.g. at atolls) or terraces.

Towed-diver observational data can be processed relatively quickly in order to get a general picture of what the reefs are comprised of (e.g. hard and soft coral cover, stressed coral, algae, etc.) and what fishes are present, while the processing of photographic and video data sets occurs back in the lab in Honolulu. Given the spatial extent of surveys conducted on this cruise, It would be impossible to convey everything recorded thus far; however, here are a few of the benthic highlights from each of the island ecosystems:

Jarvis Island

Jarvis was largely dominated island-wide by the species of hard coral Montipora aequituberculata.
The west side has an extensive population of Sinularia (soft coral) found nowhere else around the island, extending ~ 300 meters north-south at the 50 foot survey depth, and covering nearly 100% of the bottom.
Live, branching Pocillopora and Acropora coral fragments were found along the south-facing shore, suggesting a recent weather/wave event.
All macroinvertebrates (crown-of-thorns sea stars, sea cucumbers, giant clams, urchins) counts were low. While the reasons for this remain unclear, potential causes include predation pressures or lack of suitable benthic habitat.

Images obtained from towed-diver surveys of Jarvis Island: Montipora aequituberculata , left panel; Sinularia dominance on the western side of the island, upper right panel; Broken Pocillopora colonies, lower right panel

Palmyra Atoll

While towed-diver surveys recorded localized proliferation of a number of hard coral genera, the majority of benthic segments were dominated by a species of Porites along the forereef and western terrace.
Low levels of bleaching were observed within numerous genera around Palmyra; additional analysis of towed-diver photographs will further explore the extent of coral bleaching around the atoll..
Visible macroinvertebrates (crown-of-thorns sea stars, sea cucumbers, giant clams, urchins) were nearly absent from our surveys.

Images obtained from towed-diver surveys of Palmyra Atoll. Partially bleached coral, left panel; forereef, left side; the forereef benthic and fish community, upper right panel;
Missing macroinvertebrates, lower right panel

Kingman Reef

Hard and soft coral cover varied between habitats, and varied depending upon depth and exposure to wave energy. However, overall hard coral cover for all pooled surveys was nearly identical as all pooled surveys around Palmyra.
The southeastern backreef continues to harbor the highest concentration of giant clams (Tridacna spp.) of anywhere we surveys around the Pacific.
The east-side backreef adjacent to the shipwreck showed a dramatic increase in cyanobacteria at 50’ – 60’ since the previous 2008 surveys, along with the presence of a fish aggregation device (FAD) not seen before.

Images obtained from towed-diver surveys of Kingman Reef. Fish Aggregation Device (FAD) seen from below, left panel; Cyanobacteria bloom near theshipwreck , middle panel; Giant Clams along the southeastern backreef, right panel

Questions related to "Predator Dominated Reefs"

2010-04-20T14:23:00.009-10:00

We have received some great questions pertaining to the April 6th blog post entitled "Predator Dominated Reefs". It's always good to know people are intrigued and interested in our research; please feel free to keep the questions coming!

Question 1: How will global warming impact Jarvis Island?

Response by Jason Helyer, Coral Reef Specialist

This is a great question, but a difficult one to provide a straight forward answer for. Some researchers believe that the cold, nutrient-rich waters that bathe the west side of Jarvis (see blog post “Questions pertaining to the Oceanography of Jarvis Island” regarding upwelling at Jarvis) may provide biological communities at Jarvis protection from climate change associated impacts. In other words, if adjacent ocean temperatures rise, the waters around Jarvis may remain cooler thanks to upwelling associated with the EUC. This cooler water could provide protection to corals at Jarvis from bleaching from rising sea surface temperatures associated with global warming. But this is just a thought shared by some scientists and we really do not know how the oceanographic conditions around Jarvis might change with a changing climate. For example, if the EUC changed as a result of a changing climate, either weakening or deepening, the effects at Jarvis could be substantial as the impact of the current on the oceanographic conditions at Jarvis is a dominant feature structuring the reef community. This uncertainty makes it difficult to answer large questions about how systems might change from global warming and is one of the main reasons why it is important to monitor both biological and physical processes at these remote reefs.

Question 2: In reference to your post that "Jarvis has about 300 times more predatory fish biomass than the entire island of Oahu." What are the factors that reduce the predatory fish volumes in Oahu?

Response to this question as well as the following are by Brian Zgliczynski, Fish Biologist

There are multiple factors that negatively impact populations of predatory fishes. They include fisheries extraction, pollution, and habitat loss. However, fisheries extraction has been shown to have the most deleterious effect on the abundance and biomass of predatory fishes globally. Artisanal, commercial, and recreational fisheries typically target large-bodied commercially-valuable fishes that play an important role in structuring marine ecosystems. As large-bodied species are removed from the system the abundance and biomass of large-bodied predatory species available in the system is reduced.

Question 3: Does illegal fishing occur in the waters around Jarvis and what impact does it have on the trophic pyramid?

Jarvis is one of the most remote and isolated islands under U.S. jurisdiction. This geographic isolation affords Jarvis some protection from anthropogenic disturbances including fisheries. However, this same geographic isolation makes Jarvis potentially vulnerable to illegal fishing activities. As fish populations near inhabited coastal areas are reduced, the threat of commercial fisheries moving offshore to exploit resources at remote and uninhabited islands like Jarvis can become a reality. Fortunately, Jarvis has been designated as a National Marine Monument and is managed and protected under U.S. law out to the 50 nautical mile boundary. This designation provides the necessary legal protection and technologies are being developed to monitor and enforce the Monument boundaries. To date, we have not observed any signs of illegal fishing activities during our biennial reef assessment and monitoring efforts.

Question 4: How does the percentage of predatory biomass at Jarvis compare to Cocos Islands and other areas with high levels of predatory biomass?

Having conducted similar surveys throughout the tropical Pacific including Cocos Island (Costa Rica), the predatory biomass densities observed at Jarvis are among the highest. Additionally, all of the sites where predatory species are abundant display similar inverted trophic pyramids with predatory species accounting for the largest proportion of total fish biomass.

Questions pertaining to "The Oceanography of Jarvis Island"

2010-04-20T12:54:00.003-10:00

We received a question by Reille related to the blog post entitled "The Oceanography of Jarvis Island" written by Jamison Gove on 3-April-2010.

Response by Jamison Gove, Oceanographer and Chief Scientist of the current expedition

Great questions Riell! I'll do my best to answer them appropriately, but if you would like more detail on the oceanographic conditions at Jarvis Island, see Gove et al (2006) Temporal variability of current-driven upwelling at Jarvis Island

Question 1: You mention that "few places on the planet have the oceanographic and coral reef environment that is found at Jarvis" could you tell me what other places in the Pacific have both the oceanographic features and the high-productivity coral reef that Jarvis does?

Due to the remote nature of the central equatorial Pacific, I imagine there may be a few islands that have similar ecosystem dynamics as those observed at Jarvis; however, it is the particular location and shape of Jarvis Island which facilitates its oceanographic and biological uniqueness, and when combined with limited human presence over the past half-century, it remains a rarity.

Question 2: I guess something similar happens around the Galapagos and that is a result of the Cromwell Current, as well, but how does the situation there compare to the oceanographic conditions at Jarvis?

They two island ecosystems are comparable as the Equatorial Undercurrent (a.k.a. Cromwell Current) fuels the high productivity at both the Galapagos and Jarvis. That being said, fundamentally different physical oceanographic dynamics occur between the two ecosystems. At the latitude of Jarvis Island, the EUC is flowing incredibly fast for an open ocean current (~1 meter/second) at a depth of 100-150 meters. When this fast moving, subsurface current interacts with Jarvis it results in a cessation of flow, and due to pressure differences, isotherms (lines of equal temperature) are forced vertically upward to the near surface. This island-current interaction driving upwelling is a result of Bernoulli dynamics, which happens to be the very same physical mechanism which gives airplane wings lift.

Due to the upward tilt of the EUC and the thermocline from west to east across the Pacific (see figure below), the EUC is near the surface (0 – 50 meters) at the latitude of the Galapagos Islands. As such, the Galapagos are surrounded by nutrient-rich waters. The productivity at the Galapagos is also enhanced (and therefore my explanation confounded) by natural iron input associated with the geological make-up of the Galapagos Islands, but that’s another question best left for another time.

Side view of the equatorial Pacific showing the Equatorial Undercurrent flowing east along the thermocline. Note the upward tilt of the EUC from the western to the eastern Pacific. Colors indicate relative temperature, with warmer temperatures shown in red and cooler temperatures in blue. Figure modified from http://www.pmel.noaa.gov/tao/

Question 3: I wonder -- does the size of the island result in differences between one side and the other; does the upwelling affect all sides equally?

The upwelling at Jarvis only occurs to the western side of the island, principally due to the fact that the EUC is an eastward flowing current. Surprisingly, there can be a 1-3 ºC difference between the western side of the island and the eastern side (see figure below). Given that Jarvis is only 4 x 2 kilometers, this is a rather substantial gradient in temperature over a very short distance.

Temperature at 25 meters depth around Jarvis obtained from near shore conductivity, temperature, and depth (CTD) casts (locations indicated by triangles). Note the 2.5 degree Celsius difference between the western side and all other sides of the island. Figure taken from Gove et al., 2006.

Question 4: Also, could you briefly describe what kind of seasonal variation you see, or variation in El Niño years, and whether you've yet observed organism behavioral adaptations in relation to any variation?

There is definitely seasonal and interannual variability in upwelling at Jarvis. Seasonally, the strongest upwelling at Jarvis occurs during northern hemisphere spring, due to a locally shallow thermocline and shallow and strong EUC. Year to year differences in upwelling are driven by the strength of the trade winds in the western Pacific and their impacts on flow of the EUC; intensified trade winds associated with La Niña conditions favor the shoaling and strengthening of the EUC at Jarvis, and therefore strong upwelling, while a weakening of the trade winds results in a slackening and deepening of the EUC, diminishing or all together shutting down upwelling. Presumably, this variability would impact local fish and benthic coral reef communities; however, we have yet to analyze the data collected during the current El Niño to confirm this statement

Autonomous Reef Monitoring Structure (ARMS): Recovery and Processing

2010-04-19T12:00:00.007-10:00

By Molly Timmers and Russell Reardon

‘Reef Biodiversity: an Introduction’ posted on the 4th of February introduced coral reef diversity and the Autonomous Reef Monitoring Structure (ARMS). This post will explore the recovery and processing of these platforms.

ARMS awaiting removal on left, encapsulated ARMS on right

An ARMS is a tool used to assess the lesser known and cryptic reef organisms. For the past two years, sessile and motile critters have been colonizing the open and closed ARMS layers. One of our missions on this cruise has been to recover all the previously deployed ARMS for immediate shipboard and subsequent land-based processing.

We remove the ARMS from the benthos by attaching a milk crate lined with an 80 micron mesh over the center stack of plates comprising the structure. A buoyed rope is then attached to the latching straps on the crate, and the whole unit is pulled to the surface. The milk crate ensures that any recruited organisms within the ARMS will not fall out during transport. Once on the surface and in the small boat, the milk crate encapsulated ARMS is placed within seawater-filled bins and transported back to the Hi‘ialakai.

Back on the ship, the ARMS is disassembled within a tub of seawater. The milk crate is detached, and each layer (plate) is removed individually. The top and bottom of each plate is photographed to document the sessile organisms. Once photographed, a paint brush is used to lightly sweep any motile organisms off the plates and into a bucket of seawater. The plates are then placed in ethanol to preserve the DNA for future molecular processing.

An example of a plate photograph

Once every layer has been photographed, brushed, and preserved, all of the buckets of seawater used during the processing are sieved into the following bins: 5 mm, 2 mm, 500 ?m, and 100 ?m. The contents from the 2 mm, 500 ?m, and 100 ?m sieves are bulked and placed immediately into ethanol. Selected critters found within the 5 mm sieve are photographed, identified, and preserved individually while the remaining 5 mm organisms are bulked and placed in ethanol.

The final task is to scrape the sessile organisms from the all the plates. The scrapings are bulked and preserved. In this manner, we are able to remove, preserve, and store all of the sessile and motile organisms that have recruited to the ARMS.

ARMS processing in action. Upper left, disassembling; lower right, brushing;
middle, photography; lower right, sieving; upper right, scraping.

When we return to land, the contents will be sent to our partners at the Smithsonian, the Florida Museum of Natural History, and the Hawaiian Institute for Marine Biology who will begin the molecular processing and taxonomic archiving. Genetic sequencing will provide a relative index of diversity for each of our survey sites. We will then be able to compare these indices among and between sites, islands, and regions. Ultimately, this process may allow us to detect and monitor changes in cryptic diversity in an effort to understand ecosystem shifts overtime.

Examples of invertebrates found within the ARMS

Kingman Reef

2010-04-17T09:33:00.000-10:00

By Kerry Grimshaw

Kingman Reef from above

We have arrived last stop for this expedition, Kingman Reef. Located nearly halfway between American Samoa and Hawaii (1700 km/1056 mi), Kingman is the northernmost reef of the Line Islands. First discovered by Captain Edmund Fanning in 1798 it was later described in 1953 by the island’s namesake Captain W.E. Kingman. Other pre-twentieth century names for Kingman include Danger Reef, Cladew Reef, Maria Shoal and Crane Shoal. In 1856 Kingman Reef under the name “Danger Reef” was claimed by the US as part of the Guano Islands Act. Kingman was later formally annexed 1922 as an unincorporated U.S. possession of the United States.

The only emergent land at Kingman; a narrow
strip of coral rubble and coarse sand

The lagoon at Kingman Reef was used as a halfway stop for Pan American Airways flying boats in 1937 and 1938 for flights between Hawai’i, American Samoa, and New Zealand. To facilitate this overnight stop a supply ship was stationed at Kingman to provide fuel, lodging and meals. After a fatal explosion shortly after take off from Pago Pago in January 1938, Pan Am stopped flights to New Zealand via Kingman Reef and Pago Pago. A new route was later established through Canton Island and New Caledonia. In 1941 the US Navy assumed control of Kingman and maintained its jurisdiction until 2000. Kingman Reef was established as a National Wildlife Refuge on January 18, 2001. On January 6, 2009 Kingman Reef was designated as part of the Pacific Remote Islands Marine National Monument.

A cluster of Giant Clams (Tridacna maxima )
at Kingman Reef

Kingman Reef is an uninhabited, triangular shaped reef that is mostly submerged. A small, single strip of “dry land” composed of mainly of dead and dried coral skeletons, is located on the eastern rim of the reef. With the highest point of land at approximately 1 meter, the island is often awash during high tide and is inhospitable for most organisms. Despite the harsh surface conditions Kingman Reef supports a vast variety of marine life below. Approximately 130 species of corals are known at Kingman and giant clams are abundant in shallow waters. Predators dominate the waters at Kingman similarly to most of the uninhabited islands we visit.

Oceanographer Chip Young surveys
the reef at Kingman

We’ll be here for the next 6 days conducting our standard suite of work before beginning the transit home.

Palmyra undwater

2010-04-15T19:56:00.001-10:00

We've spent the past 7 days conducting surveys and retrieving/deploying oceanographic instruments in the waters around Palmyra Atoll. Here are a few photos from below the water's surface:

The soft coral, Sarcophyton sp.

Scientist Nichole Price conducts a Line

Point Intercept survey.

Oceanographer Jamison Gove installs an Acoustic Doppler

Profiler and subsurface temperature recorders.

Layers and layers of corals!

Sea slug (Elysia ornata).

The camouflage grouper (Epinephelus polyphekadion).

Oceanographers Chip Young and Danny Merritt

retrieve the Remote Automatic Sampler.

Threadfin butterflyfish (Chaetodon auriga) swimming

over a carpet of invasive corallimorphs (Rhodactis howesii).

An Acropora sp. thicket in the coral gardens of Palmyra.

A school of convict tangs (Acanthurus triostegus) swoop in

to mow the algal lawns on this section of reef.

An interesting and unusual formation of Acropora sp.

Acropora sp. tables found on the western terrace.

A blacktip reef shark (Carcharhinus melanopterus) cruising near the coral gardens.

A curious Twin-spot Snapper (Lutjanus bohar) comes in for a closer look

while oceanographer Jamison Gove installs a subsurface temperature recorder in the background.

A Napoleon Wrass (Cheilinus undulatus) swims by.

Here are a few of the critters we have found within the Autonomous Reef Monitoring Structures around Palmyra:

A swimmer crab (family Portunidae).

A spaghetti worm (family Terebellidae).

A money cowrie (Cyprae moneta).

A fire worm (family Amphimonidae)

A snapping shrimp (Alpheus sp.)

We have seen many interesting animals,both large and small, here at Palmyra Atoll. While always interesting it is time for us to continue on to the final destination of this expedition: Kingman Reef.

Looking Above Water; Jarvis Island Revisited

2010-04-13T10:55:00.001-10:00

Written by Chris Depkin, photographs by Jiny Kim

Chris Depkin surveys the wildlife at Jarvis Island

A Masked Booby (Sula
dactylatra ) chick awaits
its mother's return

Jarvis Island National Wildlife Refuge (NWR) has something to offer everyone. As you can see by exploring previous blog entrees, the underwater world is exceptional by any standard. However, if you were to crawl out of the water, up onto and over the coral rubble that forms the beach, you would see a dazzling view of life on dry land equaling that of the surrounding coral reef community. After days on the open ocean all of your senses would be simultaneously assaulted by the sound of thousands of nesting seabirds, the sight of verdant island vegetation and the fragrance of life, reproduction and death. You see, Jarvis Island, only a little over one thousand acres in size, is the only land within thousands of square miles of open ocean. As such, this island provides the only suitable conditions for as many as 13 or more different seabird species of birds, in numbers often exceeding several hundred thousand, to mate and reproduce.

The isolated nature of Jarvis Island (> 200 miles from the next nearest island) makes visitation difficult and is generally accomplished only once every two years. On 01 April, two members of the US Fish and Wildlife Service, Jiny Kim and Chris Depkin, were dropped off on the north-west shore of the island. They spent the next 5 days and 4 nights exploring the terrestrial environs for the purpose of assessing the state of the seabird communities, looking for signs of unauthorized human presence, identifying and neutralizing any hazards to wildlife, mapping and inspecting the island’s vegetation communities for changes in distribution patterns and looking for recent, non-native plant introductions.

A White Tern (Gygis alba) finds
a perch to view its surroundings

Jarvis Island supports very few plant species most of which are low growing. There are no trees on the island. During previous visits, plant species were described as brown, and dried with little flowering, dead or not detected at all. Our first impression of the island was astonishment and wonder at both the diversity and extent of coverage of the vegetation. Well over half of the island was bright green with at least 8 species well represented and most either flowering or in seed, or both.

A Hermit Crab searches for food

However, conditions favorable for plant growth and reproduction (excessive rain fall) are not necessarily conditions suitable for seabird nesting. The unusual amount of rainfall at Jarvis is likely a result of the recent El Niño-Southern Oscillation event (ENSO) which can bring about large scale changes in regional weather patterns once every 3-5 years. These large scale changes, and in particular changes in sea surface temperature (SST), also affect the distribution, abundance, availability and predictability of prey items critical to successful nesting.

The region is just now emerging from the current El Niño event and our visit to Jarvis seemed to support the above. Although thousands of seabirds were present during this visit, the vast majority were in the very early stages of nesting, either sitting on eggs or standing around, on territory, getting ready. Chris and Jiny documented the presence of very few chicks either alive or dead (dead chicks indicate earlier breeding attempts that failed) which indicates little or no nesting has occurred here over the last several months. Very preliminary and crude estimates suggest there were less than 150,000 birds present on the island during this visit. Previous visits place estimates well over one-million birds present during peak nesting.

After walking more than 30 miles during the 5 day period, locating and counting breeding birds and mapping vegetation distributions, Jiny and Chris were picked up where they were dropped off, not to return for another 2 years.

Jarvis Island is without question a rare jewel set in the vastness of the Pacific Ocean. On January 6th, 2009, President George W. Bush established the Pacific Remote Islands Marine National Monument. Jarvis Island NWR along with Howland and Baker island, Johnston, Wake, and Palmyra Atolls, and Kingman Reef are all included in this new Marine Monument which contains 86,888 square miles of mostly open ocean and the above uplands. The areas designated by this new Monument are used by over 4 million breeding tropical seabirds and at least 10 million more that are pre-breeders or migrants passing through those waters on their way to Northern and Southern breeding grounds. Protecting these remote places cannot be overstated, important not only for the marine and terrestrial organisms that live there but for the enjoyment, benefit and educational opportunities afforded future generations.

The last bit of light before the sun sets over the Pacific

Palmyra Atoll

2010-04-09T20:36:00.003-10:00

By Paula Ayotte

Palmyra Atoll from above. Photograph by Stuart Sandin

Leaving Jarvis on our 400-mile northward transit to Palmyra, we’ve again crossed the equator and have arrived at this low-lying atoll. Palmyra is considered a true atoll because it has reefs encircling three sub-lagoons and supporting many islets. Having surveyed the fish populations here in 2006 and 2008, I’m curious to see if the milkfish (Chanos chanos), blacktip reef sharks (Carcharinus melanopterus), humphead wrasse (Cheilinus undulatus), schools of twinspot snapper (Lutjanus bojar), and manta rays (Manta birostris) that I remember will again make their way into my transect to be counted. Palmyra was discovered by the captain of the American ship Palmyra in 1802, but was not claimed until 1862 when ownership was asserted by Captain Zenas Bent and J.B. Wilkinson for the Kingdom of Hawai’i. Although Palmyra was also claimed by United States under the Guano Islands Act of 1856, it was not actively mined as approximately 180 inches of rainfall per year made it too wet for guano accumulation.

A school of Rainbow
Runner (Elagatis Bipinnulata).
Photograph by Danny Merritt

The British also claimed Palmyra in 1889. The Pacific Navigation Company bought Palmyra in 1885 and the company’s interests were conveyed in 1911 to Judge Henry Cooper via petition to the Land Court of the Territory of Hawai’i. Judge Cooper sold all of Palmyra except two islets to the Fullard-Leo family in 1922. In preparation for possible war, the US Navy attempted to lease Palmyra from the Fullard- Leo family in 1938. However, in 1939 the US Congress authorized construction of a naval base at Palmyra, and the US filed suit to annex the atoll. Up to 6,000 servicemen occupied Palmyra Atoll Naval Air Station during the World War II era. In 1947 the US Supreme Court, returned ownership of the atoll to the Fullard-Leo family. The 1959 Hawai’i Statehood Act specifically excluded Palmyra, and by that time US Navy occupation had ceased and all other federal presence at the atoll ended. Subsequently, the atoll remained abandoned except for resident caretakers supported by the Fullard-Leo family.

Manta Ray (Manta birostris),
Palmyra Atoll. Photograph by Chip Young

In 2000, Palmyra was purchased by The Nature Conservancy (TNC), and in 2001 the USFWS purchased all of Palmyra from TNC except for the main island (Cooper) and established the Palmyra Atoll National Wildlife Refuge (NWR). In 2006, TNC completed construction of a research station at Cooper Island, where up to 20 scientists and staff can be housed. While we’re here we hope to have the chance to meet with several of the scientists currently on the atoll to discuss our common research goals and find out what their experiences have been working for weeks or months at a time on Palmyra.

Predator Dominated Reefs

2010-04-06T20:35:00.003-10:00

By Brian Zgliczynski

Typical reef scene at Jarvis Island with large-bodied predatory species
patrolling the reef.

If you could ask any of the scientists aboard the Hi'ialakai to describe what it's like to dive at Jarvis Island, you would hear something like: “mind-blowing, intimidating, exhilarating, intense, eye-opening“. If you heard these words alone you would think we were out here in the central Pacific filming an energy drink commercial, or certainly something other than conducting scientific research. However, this is definitely not the case, and Jarvis Island is all of this, and more. The first thing we notice upon arriving at a dive site are ominous shadows circling below. As we perform pre-dive checks and review survey protocols, you can’t help but wonder what awaits. The few minutes just before a dive can be filled with anticipation, and quite an adrenaline rush.

Predatory species like jacks and sharks
are abundant at Jarvis

Upon entering the water the ecological monitoring team is greeted by numerous predatory fishes such as grey reef sharks (Carcharhinus amblyrhynchos), twinspot snapper (Lutjanus bohar), black trevally (C. lugubris) , and coral grouper (Cephalopholis miniata). Large-bodied predatory species, which are common at Jarvis, are becoming increasingly rare throughout the tropical Pacific with fisheries exploitation exerting direct impact on reef-fish communities. Predatory species play an integral role in structuring coral reefs and the systematic removal of these important species can have detrimental impacts to the ecosystem.

CRED divers conduct surveys recording species composition as well as the number and size of all fishes observed in a predefined area. These data are converted into measures of abundance and biomass and used to estimate fish populations around an island or reef. At Jarvis, predatory species are highly abundant and account for over half of total fish biomass. Reef scenes like the one pictured above are commonplace. To put this into perspective, Jarvis has about 300 times more predatory fish biomass than the entire island of Oahu. The research conducted here has altered our perspective of the typical trophic pyramid in which predators (tertiary consumers) comprise a small fraction of total fish biomass in a reef ecosystem. At Jarvis Island, the trophic pyramid is inverted, with top predators accounting for a majority of fish biomass.

Trophic pyramids with species divided into their respective trophic categories.
Tertiary consumers = top-level predatory species, planktivores = species that
feed on microscopic organisms, Secondary consumers = lower-level carnivorous
species, and Primary consumers = herbivores. The Pyramid to the left represents
a degraded system with few predators (tertiary consumers) while the pyramid to
the right represents what researchers have observed at Jarvis Island,
where predators are highly abundant.

As predator dominated coral reef ecosystems become increasingly rare in most parts of the world, contemporary ecological studies concentrate efforts on systems that have already been degraded. However, Jarvis Island and other U.S. Pacific islands represent some of the remaining examples of ecosystems in their natural state. Such systems provide an ecological baseline and an unprecedented opportunity for marine scientists to understand what ‘pristine’ coral reef ecosystems are like, aiding in the formulation of appropriate metrics necessary for developing effective ecosystem-based management and recovery plans towards the future.

The Oceanography of Jarvis Island

2010-04-03T22:44:00.007-10:00

By Jamison Gove

Grey Reef Sharks often congregate in the tens to hundreds at Jarvis Island

There is an intimate and inseparable link that exists between oceanography and coral reef ecosystems. Ocean waves, currents, temperature, salinity, and nutrient availability are each important and play a significant role in determining not only the diversity and abundance of organisms an a coral reef, but can also dictate the morphology (shape) of coral and algae species and the substrate they inhabit. For example, corals which are consistently battered by ocean waves tend to be low-lying and mound-shaped, lacking the large, delicate and branching structures that are often found in more benign, wave-free environments.

A few Raccoon Butterfly fish
make their way down the reef

In some places around the world, this connection between coral reef ecosystem dynamics and the surrounding environment can be subtle; however, at Jarvis Island this elemental relationship is so abundantly clear you would have to be sound asleep to miss it. In other words, you can actually see oceanography in action.

Schools of small fish are common
at Jarvis Island

Due to its location in the central equatorial Pacific, Jarvis is impacted by a strong, cold, nutrient-rich ocean current flowing below the surface, centered at approximately 150 meters depth. This current, known as the Equatorial Undercurrent, is spawned in the far western Pacific and flows eastward along the equator and across the entire Pacific Ocean. When this fast-moving current interacts with Jarvis Island, it forces deep water to the near-surface, providing copious amounts of nutrients to the surrounding coral, algal, and fish communities. These nutrients are quickly assimilated by the reef community, fueling an astonishingly productive and ecologically vibrant coral reef system. Few places on the planet have the oceanographic and coral reef environment that is found at Jarvis, making it a unique and special place not only for scientific research, but also for protection for many generations to come.

Jarvis Island

2010-03-31T20:23:00.016-10:00

by Paula Ayotte, photos by Jamison Gove

After five days of transit from Pago Pago, we’ve finally arrived at Jarvis Island, the sixth island in the Line Islands chain. This puts us once again close to the equator, about 1,000 miles from American Samoa, 1,200 miles from Honolulu, and 400 miles from our next stop, Palmyra Atoll. For some of us on board, this is a return trip to this remote island chain. For others, this will be their first expedition to the Line Islands. Regardless of how many times we’ve been here, how many dives we’ve already done, how many fish or corals we’ve counted, or how many oceanographic instruments we’ve deployed or retrieved, all of us are looking forward with great anticipation to getting in the water and conducting research at Jarvis Island.

The coral reef ecosystem at
Jarvis Island.

On land, this low-lying, arid, warm, lopsided rectangle of land seems unprepossessing, but underwater it’s a wonderland of swirling anthias, curious sharks, and schools of jacks amid an impressive variety of colorful corals. What contributes to the amazing diversity at Jarvis is the remote location and isolation from detrimental human impacts, along with its location in the path of the easterly flowing Equatorial Undercurrent which brings nutrient rich waters upward, enriching the primary productivity of the surface waters surrounding Jarvis.

Though Jarvis is relatively free from human exploitation, like Howland, Baker, Palmyra and Kingman, Jarvis was claimed for the United States under the Guano Islands Act of 1856. Baker, Howland, and Jarvis Islands were also claimed by the United Kingdom as British Overseas Territories from 1886 to 1934, and guano mining was conducted by both British and American companies through the end of the nineteenth century, after which guano deposits were largely depleted. As at Howland and Baker, a small colony of Kamehameha School graduates was established in 1935, which became known as Hui Panala'au (Society of Colonists). These colonists occupied these islands continually, in three-month shifts of four men per island, in an attempt to help the United States assert territorial jurisdiction over the islands, a jurisdiction crucial to air supremacy in the Pacific. Water and bulk food were supplied from Hawaii. During the period between 1935 and 1942 era; at least 26 trips were made to Jarvis Island by various United States Coast Guard (USCG) cutters. Jarvis Island was evacuated at the beginning of World War II and was unoccupied during the remainder of the war.

A Green Sea Turtle drifts gracefully by.

Post World War II, there were no attempts to re-colonize the island, and in 1948 the United States Coast Guard began making annual visits to maintain claim to Jarvis. In March 1963, and for the following 2 years, Smithsonian Institution employees made a number of visits to Jarvis Island as part of the Pacific Ocean Biological Survey Program. The island and its territorial seas were transferred to the US Fish and Wildlife Service (USFWS) in 1974 from the Department of the Interior. This area is now managed as a unit of the National Wildlife Refuge System and in 2009 was established as part of the the Pacific Remote Islands Marine National Monument.

Safety First

2010-03-29T17:55:00.015-10:00

by Jamison Gove

The NOAA Ship Hi'ialakai

Painted in sizable black letters and readily seen against the stark white background of the towering exhaust stacks are two important words: Safety First. These words provide not only a daily reminder of the often unpredictable and precarious nature of seafaring work, but also serve as a testament to the professionalism and commitment of those aboard the Hi'ialakai to conduct safe and impact free operations wherever the ship may travel.

Scientist Chip Young
dons a survival suit

The past few days have been spent instructing the new members of the expedition on the safety procedures in place aboard the ship in addition to providing refresher training for existing personnel. Abandon ship drills, life-raft familiarization, fire drills, dive-gear check outs, oxygen delivery and reviewing diver rescue protocols are just some of the trainings being conducted en route to Jarvis, ensuring that everyone aboard is well equipped to avoid a potential hazard and navigate any situation that may arise.


Chamber Supervisor Jim Bostick provides an overview of the recompression chamber

An intrinsic part of coral reef research is repetitive and arduous SCUBA diving. Since this expedition began, scientists have conducted over 2000 dives, quite a lot considering the ship left Honolulu just over 2 months ago! Due to the high quantity of dives combined with the remote island locations visited during this research cruise, an essential piece of safety equipment carried on board is a Recompression Chamber, a 52-inch diameter pressure vessel used to treat dive related maladies such as Decompression Sickness (DCS). The chamber has been on the Hi'ialakai since the ship was first commissioned in 2004 as a vast majority of the research conducted on board is diving related. Although the chamber is autonomous, meaning it can operate independent of the Hi'ialakai's power supply, it does require a Chamber Supervisor to properly operate the chamber, a Dive Medical Officer (DMO) to coordinate medical treatment and a Dive Medical Technician (DMT) to tend and care for the injured diver inside the chamber. Each of these people are extensively trained and are present for every dive expedition the Hi'ialakai embarks on, providing security and piece of mind to each of us divers on board the ship.

Goodbye to Amercian Samoa

2010-03-27T20:33:00.009-10:00

by Jamison Gove

The Hi'ialakai heads to Jarvis Island

After spending nearly six weeks conducting coral reef research in and around American Samoa, the day has finally arrived to say our goodbyes to the island of Tutuila. With all twenty-two scientists and twenty-five crew members aboard, the Hi′ialakai cast off her lines from the pier early this morning and made a slow and steady departure out of Pago Pago, gently swaying back and forth as we emerged from the quiescent harbor and into the rolling seas of the open ocean. Heading northeast, we’ve now begun the five day journey to Jarvis Island, our first destination of the third and final leg of this expedition. These next few days will be filled with safety drills, scientific planning meetings, trainings, and gear preparation in anticipation for our arrival to Jarvis.

Back in Pago Pago

2010-03-25T14:17:00.000-10:00

by Benjamin L. Richards
The Hi'ialakai is back in Pago Pago for the change-out between Leg 2 and Leg 3 of the expedition. We held a one day education and outreach program for local school children and members of the public on March 23 and conducted calibration dives between the outgoing and incoming researchers on March 24. We will be spending the next few days refitting the ship and small boats for the next leg of the expedition, meeting with local government and agency representatives and getting some much needed rest before we head off to the Line Islands (Jarvis, Palmyra, and Kingman Reef) on March 27. Stay tuned for new discoveries as we reach the Line Islands and start making our way back north.

A few more questions on Rose Atoll

2010-03-21T20:15:00.003-10:00

Coralline algal formation at Rose Atoll,
Porolithon craspedium (Photograph by
Cristi Richards)

We have received more questions regarding Rose Atoll from Samoana High School students and would like to take the time to provide these answers. We are excited that our work has generated such interest and hope that the questions keep coming. It is important to monitor reef health, but it is just as important to be sure that our findings are reaching the public and those interested. We hope that these answers help to clarify and provide more depth to our previous posts. Enjoy!

Soshana asks: Whenever you guys visit the Rose Atoll Island, do you discover anything new?

Good question Soshana!
I am not aware of any new discoveries made by us at Rose Atoll during our past visits. Every once in awhile our scientists have discovered a new species and that is always quite exciting!

More often the “discoveries” we’ve made have been documenting natural phenomena such as coral bleaching, sites with internal tides, and range extensions for various species of fish, algae, and corals. Many other discoveries are known to the local population and those living in the area, but may be unknown to the scientific community or to people living in other parts of the world. This trip we “discovered” that South Bank is a drowned atoll. As far as we know, this was previously unknown until our team completed multibeam surveys of the area!
- Kerry Grimshaw

Marissa asks: According to the picture (Photograph from noaa.coris.gov), is there any other possible ways to help save Rose atoll from sinking?
[The picture Marissa is referencing can be found on an earlier blog post]

Marissa,
I’m sorry to report that there is no easy answer to your question, although I like where your heart is! Islands may have many different fates over time and it all comes back to the geologic processes that take place. Fortunately, these processes generally take millions of years to happen, so it’s unlikely that you’ll see much change in the sinking of Rose Atoll during your lifetime.

On another note, the current hot topic of climate change could have significant effects on Rose Atoll in the future, particularly related to sea level rise and ocean acidification.
The excerpt below is from an article posted May 29, 2007 on the BBC website:

The Death of Islands

Exposed reef covered in coralline algae at Rose Atoll
(Photograph by Cristi Richards)

The world is constantly changing and islands will not live forever. There are four main fates for an island:

It may be brought up against a larger land mass by continental drift. 40 million years ago, this happened to the island of India, when it collided with the continent of Asia. The resultant crash hasn't finished yet - the Himalaya mountains are the crumple zone, where the folded Earth's crust absorbs the impact of India with the rest of Asia.
A small island may be eroded by the elements until there is nothing left above water. This was the fate of the westernmost of the Hawaiian Islands, which are now under the sea.
An island on an oceanic tectonic plate may be slowly dragged under the ocean as the plate collides with another plate and is subducted, that is, is pushed in under the other plate. This is the ultimate fate of each of the Galapagos islands. After they are created over a mid-ocean hot spot, they travel east until the plate they are on collides with and slides under the South American plate. The easternmost islands of the group are sliding back down into the ocean.
Changing currents in the Earth's mantle can cause a section of the ocean floor to be raised up, and subsequently to sink back down again. The Kerguelen Plateau, in the southern Indian Ocean, is now about two kilometres under the sea, with just a few isolated peaks showing above the surface as the Kerguelen Islands, but 100 million years ago, it was raised up to form an island three times the size of Japan. It is likely that it had animals and plants living on it. Then about 20 million years ago, the mantle currents changed and it slowly sank back down into the sea.

All of these slow deaths take millions of years to come about. In the meantime, islands continue to exert a fascination on mankind.
- Kerry Grimshaw

Valentine asks: Are there any human beings living on Rose Atoll?

Valentine,
No one lives at Rose Atoll and historically it has mostly been uninhabited with the exception of a brief time in the 1860s when the German government tried to establish a fishing station and coconut plantation. They didn’t have much luck as one of the 2 islands is often nothing more than a shifting sand bank!
- Mark Manuel

Oina asks: Are we allowed to visit Rose Atoll on our own or do we have to go with some sort of researchers?

Hi Oina,
As of now, the Rose Atoll National Wildlife Refuge is closed to the public. This closure is to protect fragile seabird colonies, endangered species, and island habitats. Special use permits to conduct scientific research can be obtained from the Pacific Remote Islands National Wildlife Refuge Complex office in Honolulu. For more information see www.fws.gov/roseatoll

With Rose Atoll recently being designated a Marine National Monument there are likely to be more regulations established for the area in the near future as visitor access is often considered in the regulations governing National Monuments. Until those new regulations are in place it is hard to answer your question completely. I would expect that there will be a permit system set up for controlling the work that can be done within the Monument. While it sounds like there may be lots of rules, we are used to obtaining permits for our work within various protected areas such as Sanctuaries, National Parks, Marine National Monuments, National Wildlife Refuges, and other territorial or commonwealth Marine Protected Areas.
- Kerry Grimshaw

Swain's Island

2010-03-17T16:35:00.002-10:00

by Kerry Grimshaw

Swain's Atoll (Photograph by Kerry Grimshaw)

This morning we started work at the last of the islands in the Territory of American Samoa: Swains Island. Although Swains is part of American Samoa, geologically and geographically it is an atoll in the Tokelau Archipelago. Swains Island is the northernmost island in the Territory of American Samoa and lies about 350 km (220 mi) north-northwest of Tutuila.

It is thought that the first European to discover the island was Pedro Fernandez de Queiros in 1606 and named it Isla de la Gente Hermosa (“island of the beautiful people”). After that the island was unvisited by Europeans until 1840 when Capt. W.C. Swains of New Bedford, Massachusetts visited and thinking he was the first to land there, he named it Swain’s Island. The British Capt. Turnbull also claimed to have discovered the island and sold Swain's Island to the American Eli Hutchinson Jennings Sr. In 1856 Eli and his Samoan wife Malia moved to the island and claimed it with the US flag (as a semi-independent proprietary settlement of the Jennings family). Swain's Island was also claimed by the US Government under the Guano Islands Act in 1860. The ownership of the island was passed down to Eli Jr. who managed the copra plantation which was established by his father. Upon Eli Jr.’s death, the US government on March 4, 1925 granted the right of administration jointly to his children Ann (the estate) and Alexander (the island) while concurrently making it officially part of American Samoa by annexation. The island is currently inhabited by 4-30 people at any given time in order to retain private ownership by the Jennings family and as part of the Territory of American Samoa.

Swains Island as seen from space

Swains as an atoll is unusual due to its unbroken circular island which encloses a central “brackish” lagoon. Swains has a total area of 1.9 sq km (0.7 sq mi) and is approximately equivalent to 380 football fields. The ring-shaped island is still encircled with coconut trees although the copra plantation is no longer active. The outer edge of the atoll consists of coral reef flats that are awash at low tide. CRED multibeam mapping surveys in 2006 revealed that like Ta’u there are little or no shallow banks surrounding the island and the reef descends to abyssal depths less than 1 km off shore. After our 20 hour transit to Swains we’ll be spending the next 3 days working and monitoring the coral reefs here.

Rose Revisited

2010-03-16T09:38:00.001-10:00

Coralline algal and coral formation at Rose
Atoll (Photograph by Cristi Richards)

It’s always great to know that people are interested in the work we do to monitor and conserve coral reefs. Recently we’ve learned that Ms. Lui’s Marine Science class form Samoana High School class in Utulei, American Samoa has been following our blog. We’ve recently received a list of questions from them that we’ll be answering in the next few blog posts. It’s a good feeling knowing that the next generation of young people are as excited about Marine Science as we are!

Joseph writes: What types of corals did you see at Rose Atoll that are different from those at Johnston Atoll?

Hi Joseph,
That’s an excellent question! Rose and Johnston Atoll are located in distinct geographical regions and as such, they exhibit unique coral faunas. For example, the table coral Acropora cytherea and the rice coral Montipora capitata are quite common and abundant on the shallow reticulate reefs at Johnston Atoll lagoon. In contrast, corals of the genera Montastrea, Coscinaraea, and Astreopora which are absent at Johnston, are quite common around Rose Atoll. However, regardless of how far away are Rose and Johnston from each other (>1000 miles), there are a few, shared coral faunal elements, including the cauliflower coral Pocillopora mendrina, and the corrugated coral, Pavona varians.
- Dr. Bernardo Vargas-Angel

Lita writes: How come there are different species around the rose atoll island when it’s just a small remote island?

Hi Lita,
It is difficult to answer why the corals are so different at Rose compared to Tutuila, although distance (240 km from Tutuila), differences in geomorphology (Rose is a low lying atoll compared to a mountainous island), island size and shape (Rose has a land area of 21 hectares and a height of 4 meters, while Tutuila has a land area of 14,181 hectares and a maximum elevation of 653 meters) likely contribute. Many of the corals that are found around Tutuila are also found around Rose Atoll, although there are not as many coral species that inhabit Rose. Also, the relative abundance of species is very different between the areas. Tutuila likely harbors more species of coral because there is more reef area and thus more chance for different types of habitat to develop, which can provide homes for corals. Certain corals like a lot of water motion from waves, while others prefer very calm waters. Some corals like a lot of sunlight, so they live in the shallows, while others prefer deeper darker waters. Since Tutuila also has mountains, waterfalls, and streams, lots of sediment and nutrients may flow into the sea creating another habitat that is not found at Rose since the island is so short! Also, due to Rose Atoll's tiny size, wave swells originating from far away can impact almost all sides as the waves wrap around the atoll. Whereas ocean swells which approach Tutuila will likely be blocked by the shores of the island in certain areas which create more protected habitats. Likely a combination of these factors and potentially others result in the difference in coral communities between the islands.
- Jason Helyer
While Jason’s answer speaks mostly about corals, this same reasoning can be used to explain the differences in the species of fish, algae, and other invertebrates.

Motina writes: How would you compare the Rose Atoll with the other atolls you have visited? Was the Rose Atoll the best view of the underworld you have ever seen? Are there any changes of the Rose Atoll?

Hi Motina,
Every one of the atolls we visit is different from the rest. A lot of this has to do with what geographic region it is located in. Rose Atoll is pretty spectacular and is unlike many of the other places we visit due to the incredible abundance of the crustose coralline algae. It’s this algae that give the reef its vibrant pink color! The vivid pink color combined with the clear blue water and the various other colors found among the corals, fish and algae certainly make it a beautiful place and fantastic for underwater photography!

As far as changes to Rose Atoll from previous years I did not observe any noticeable differences from my visit to Rose Atoll in 2008. However, sometimes differences can be quite small and may not be realized until we take a deeper look into the data and comparing it to years past.
- Kerry Grimshaw

Soshana writes: How long have you guys been visiting the Rose Atoll Island?

Hi Soshana,
We (NOAA’s Coral Reef Ecosystem Division) have been visiting Rose Atoll since 2002 during our biennial American Samoa Reef Assessment and Monitoring Program cruise. This year was our 5th trip to Rose Atoll.
- Paula Ayotte

Thank you for all of your questions and we will continue to answer them in the upcoming days!

The Oceanography Team

2010-03-14T23:05:00.005-10:00

by Oliver Vetter

Frank Mancini and Oliver Vetter using a liftbag to deploy the Remote Access Sampler
(Photograph by Noah Pomeroy)

As part of our Pacific RAMP cruises, several types of oceanographic instruments are deployed to continually measure water conditions at our research sites. These instruments remain in place for a period of 2 years and are maintained during each cruise. To accomplish this, the oceanography team’s daily operations typically include deploying and recovering oceanographic instruments. These can be small, like the numerous subsurface temperature recorders we’ve deployed, or larger like a wave and tide recorder or sea surface temperature buoy. The larger instruments require the installation of large anchors to hold them to the sea floor under strong currents and waves. The anchors we typically use are 250lbs, which are obviously too heavy for a single person to carry either above water or below. To deploy these anchors we use lift bags, which are basically bags filled with air that float the anchor when full. At the surface the bag is full and the diver slowly releases air out of the bag until the weight of the anchor, being pulled down by gravity, equals the upward buoyancy of the lift bag. At this point the bag can be submerged and starts to slowly descend to the sea floor, preferably under the control of the oceanographer. Since the water pressure increases with depth as you descend through the water column the additional water pressure compresses the volume of the lift bag and so reduces its buoyancy. This causes the anchor to sink faster and in turn reduce the buoyancy and sink even faster, so air has to be slowly added again and again to keep the lift bag from dropping too quickly and out of control. This can be a tricky balance of releasing and adding air, to drop the anchor under control to the seafloor.

Once at the bottom, the new instrument is clamped to the anchor and the old instrument and anchor are removed in the same, but opposite way; the air bag is refilled, and the anchor is raised from the bottom. This time the oceanographer has to be particularly careful not to raise the anchor too fast, or let it get out of control. When diving shallower than 130 feet on normal SCUBA, the diver should ascend at a rate no quicker than 30 feet per minute to avoid decompression sickness. With proper training this kind of work is safe and it’s a matter of pride among the oceanography team to get a good lift.

In the picture, Oceanographers Oliver Vetter and Frank Mancini are retrieving a Remote Access Sampler (RAS), an instrument that can be programmed to collect water samples at predetermined intervals. This RAS was programmed to collect water samples every hour through out a 48-hour period at Rose Atoll. The water samples will be analyzed for Dissolved Inorganic Carbon and Total Alkalinity in an effort to understand the water chemistry of the reef throughout the day. This is part of a larger effort to understand and predict the ecological impacts of ocean acidification.

Ancient Corals of Ta'u, American Samoa

2010-03-12T23:06:00.007-10:00

by Douglas Fenner

The largest known coral colony
(Photograph by Paul Brown, NPAS)

On the southwest coast of Ta’u Island, American Samoa, there is a coral of massive proportions. It is a smooth hemispherical coral in the genus Porites. It measures 7 m (23 feet) tall and has a circumference of an amazing 41 m (135 feet). It is in near-perfect condition, with one narrow cleft that is dead and one low tumor the size of person. The tumor retains the color and polyps of the normal coral, it is just raised a little, and these types of tumors appear not to hurt the coral. It is the largest circumference coral we know of in the world (so far), although it is not the tallest. There is another coral in Taiwan that is taller.

This ancient coral is estimated to have 200 million tiny polyps, and to weigh 129 metric tons. It is clearly old, but we don’t know for sure how old. Australian researchers have come up with a formula for how fast this type of coral grows, based on water temperature. Due to relatively high water temperatures in American Samoa, corals grow faster than elsewhere. The formula indicates it should be about 360 years old. The only way to find out for sure is to remove a core from it, which has not been done. Whatever its age, we know from its good health and size that conditions there have been favorable for corals in this area for a longtime.

Diver next to the tumor on the
largest known coral
(Photograph by Paul Brown)

Small samples of the skeleton show that it is in the Porites lutea group of corals. Genetics indicates that there are at least three species in this group, all of which have similar skeletal details. Coral species identification is based on details of the skeleton.

This coral was originally pointed out to researcher Dr. Alison Green by a Samoan employee of National Parks, Fale Tuilagi. Subsequently, CRED has found more corals of similar size on the east side of Ta’u. Ta’u is a shield volcano like Mauna Loa in Hawaii, the youngest island in the Samoan archipelago at a mere 100,000 years, and home to the village from which voyagers set out over a thousand years ago to settle all of the Polynesian islands. It is also where Margaret Mead did her research that led to her famous anthropological book, “Growing up in Samoa.”

Reference:

Brown, D. P., Basch, L.,Barshis, D., Foresman, Z., Fenner, D., Goldberg, J. 2009.

American Samoa’s island of giants: massive Porites colonies at Ta’u island. Coral

Reefs 28: 735.

Ofu & Olosega Islands

2010-03-11T23:30:00.003-10:00

View of the south side of Ofu (left) and Olosega (right)
(Photograph by Kerry Grimshaw)

By Kerry Grimshaw

We are currently working near the islands of Ofu and Olosega, which are part of the Manu’a group of islands (which also includes Ta'u). They lie approximately 100 km northeast of Tutuila. Although geographically separate, these islands are often referred to together because they are only separated by a narrow straight (approximately 75 m) that is bridged by a shallow coral reef. The twin islands of Ofu (on the west), and Olosega (on the east) are formed by two sharply eroded, overlapping shield volcanoes which gives these islands a dramatic landscape.

Ofu and Olosega are inhabited with the majority of their population (approximately 500 people according to the 2000 census figures) living in the 2 main villages of Ofu and Olosega. An interesting fact I learned from the National Park of American Samoa’s website is that the To’aga archeological site near Ofu Beach has evidence of more than 3,000 years of continuous human occupancy and some modern descendants still live nearby in Ofu Village.

The south-coast beach of Ofu-Olosega with it’s the 4km (2.5mi) stretch of white sand is one of the most beautiful in the South Pacific. Much of the southern coast is also part of the National Park of American Samoa. Along this stretch there are excellent opportunities to snorkel and see some of the 300 species of fish and 150 species of coral that can be found there. Through our shallow water multibeam mapping in 2004 we learned that Ofu and Olosega had a previously uncharted bank top that is less than 300m deep and extends between 0.2 – 2km offshore before dropping to abyssal depths.

Our work this year will continue efforts to monitor fish, coral, algal, invertebrate, and microbial communities at depths ranging from 3 - 30m (10 - 100 feet) deep, as well as a suite of oceanographic observations to better understand the processes influencing these organisms. This data will be compared with that from the other islands we've visited to get an understanding of overall reef health of this area of the world.

Exploring South Bank

2010-03-10T17:54:00.002-10:00

by Cristi Richards

Exploratory map of South Bank, American Samoa
(ARC GIS map created by Tomoko Acoba)

South Bank is a sub-surface rise in the ocean floor, or seamount, located approximately 37 miles south of the island of Tutuila. Until recently, there has been little scientific knowledge about the depths, habitats, or living communities of South Bank. Reported minimum depths varied widely and proposed minimum depths from 10 meters (30 feet) to 30 fathoms. Fisherman have known about and frequently visit South Bank in search of wahoo, tuna, and other pelagic fish that are attracted to the shallower depths. However, it appears that South Bank has only very rarely been observed underwater.

South Bank is probably not part of the Samoan chain, in geologic terms, due to its location and age. The Samoan chain has been building from the Pacific plate moving over a hotspot, creating islands in a similar fashion to the Hawaiian chain. The older islands are found to the west with the youngest islands in the east. However, South Bank may be greater than 10 million years old, much older than the other Samoan islands in the area. This is similar to how Swains and Rose Atolls are geologically not part of the Samoan chain either, despite their proximity.

Heliopora coerulea, Blue Coral at South Bank
(Photograph by Cristi Richards)

In an effort to understand more about this area, we spent several nights last week mapping South Bank using the multibeam sonar installed in the hull of the NOAA Ship Hi’ialakai. For the first time, we found that not only is South Bank a shallow spot in the ocean floor, but it is a former coral atoll which drowned at some point. We can tell that it is a former atoll by the submerged barrier reef, a ring of shallower depths, surrounding a deeper lagoon with a minimum depth of approximately 25 meters (85 feet). There was only one previous known dive to the area that reported the presence of a rubble flat and high currents. Based on this, we planned a series of reconnaissance dives with members from the fish, benthic, oceanography and towed-diver survey teams aboard the Hi’ialakai. Our survey techniques had to be modified to accommodate the deeper habitat and reduced dive times. We were able to complete a total of 36 person dives and approximately 5 km of towed-diver surveys along the raised rim, encircling the lagoon. We encountered mostly rubble flats with a high abundance of macroalgae and low coral cover and diversity. The area seemed highly scoured and although we experienced only moderate currents, it is probable that the area is subjected to high currents.

South Bank appears to be a reef that has not kept up with sea-level rise, the sinking of the atoll due to the weight of the original island at its center and the sinking of the Pacific plate. It is unclear what the original reef ecosystem was like and it is a mystery why this reef wasn’t able to keep up with these processes. Rose and Swains Atolls experience similar conditions, yet continue to have thriving reef ecosystems. South Bank is an area that will require more investigation to fully understand the history and processes of this submerged atoll. It is exciting that the new investigational maps and surveys may provide more information to aid in future explorations.

More cool critter sightings

2010-03-09T14:32:00.000-10:00

We are currently at the dock in Pago Pago Harbor, waiting for deliveries so that we can continue our work eastward to Ofu / Olosega and Ta'u. Until we are able to leave dock, these are a few more photos of critters that we see while on the reef. All of these pictures were taken in a reef environment between 10 and 20 meters (30 and 60 feet). Enjoy!

Gomophia sp., a type of Sea Star
(Photograph by Molly Timmers)

Crinoid (Photograph by Erin Looney)

Dardanus sp., a type of Hemit Crab
(Photograph by Molly Timmers)

Gymnothorax sp., a species of Moray Eel
(Photograph by Erin Looney)

Octopus sp. (Photograph by Molly Timmers)

Herbivores!

2010-03-07T11:15:00.000-10:00

by Kaylyn McCoy

Acanthuras triostegus, Convict surgeonfish forming a feeding
aggregation (photograph by Cristi Richards)

As my dive buddy and I are ascending from a dive, she points behind me and puts her hand to her forehead, making the sign for “shark.” I whip around, full of anticipation and hoping to catch a glimpse of a 12 foot Tiger Shark (Galeocerdo cuvier), preferably swimming away. But, it’s just a three foot Black-Tip Reef Shark (Carcharhinus melanopterus), cruising around below us. Big fish like sharks and jacks are exciting and important, but we can’t forget about the little guys! Above is a picture of a school of Convict surgeonfish (Acanthurus triostegus). These fish are herbivorous, and feed on the algae that grows on the reef. Certain species like these Convict Tang form dense feeding schools possibly to overwhelm smaller, but incredibly aggressive damselfish defending their territories. Herbivorous fish play an important role in maintaining equilibrium in an ecosystem. Without these fish, certain species of algae can grow out of control, smothering the corals of the reef.

Scarus xanthopleura, Red Parrotfish
(Photograph by Paula Ayotte)

Another algae muncher that we see on the reef is the red parrotfish (Scarus xanthopleura). These fish have a specialized “beak” or dental plate used for scraping the algae off of the reef. Some parrotfish simply scrape the algae off the surface while other, usually larger species, bite of sizable chunks of the reef. Sometimes when we are counting fish, we can actually hear them feeding. Much of the sand you see on a coral reef may have passed through the belly of a parrotfish at one time or another.

Some areas of the Pacific are considering protecting specific herbivorous fish to help control invasive algae. So while it’s exciting to think about a shark snacking on a poor unsuspecting fish, don’t forget about the importance of the herbivores, the lawn mowers of the reef!

Sighting the rare Guitarfish

2010-03-05T11:42:00.002-10:00

by Marie Ferguson

A Shovelnose Guitarfish (photograph courtesy of www.Elasmodiver.com)

A few days ago, while conducting a fish REA (Rapid Ecological Assessment) survey my dive buddy, Rusty Brainard, and I enjoyed a rare sighting of a Rhynchobatus djiddensis, Whitespotted Guitarfish, along the northwest side of Tutuila. The guitarfish was spotted while conducting a deep SPC (Stationary Point Count) survey, at approximately 70 feet. We had just completed our final SPC and were on our way to the surface for our safety stop when the 4 foot long guitarfish swam by us with a remora (‘shark sucker’) attached to its underside. Up until this point, a Whitespotted Guitarfish has never been observed or recorded by our research team in American Samoa or other locations during the many thousands of surveys we have conducted across the Pacific Islands over the past decade.

Rhynchobatus djiddensis belongs to the Rhinobatidae or Guitarfish family. It is unique in that it resembles a cross between a shark and a ray with the anterior or front half of its body looking like a ray while the posterior or rear half looking like a shark. Like other rays, guitarfish have small mouths with teeth that are flat and pavement-like and generally prey on crabs, cephalopods and small fishes. Most guitarfish species have been known to occur on continental shelves or insular shelves of large islands in roughly 2 to 50 meters of water depth. Due to the variation over its range, this type of guitarfish has been divided into approximately 5 to 6 species. Little is known about the biology of this species, however data collected has suggested that it does have a low fecundity and very slow growth rate.

According to the ICUN Red List of Threatened Species, the large size and nearshore areas that this species inhabits make it highly susceptible to gillnet and shallow-water trawl fishing. In several parts of the world, such as Tanzania, Rhynchobatus djiddensis is being exploited mainly for its fins and is being commercially fished in bottom-set gillnets. Data recorded has also shown that this species is caught as bycatch in prawn trawls. Other documented areas where this species of guitarfish is either fished intentionally or as bycatch include shores off of Kenya, Mozambique, East Africa and the Middle East in the Western Indian Ocean, many areas in which policing and regulatory enforcement is often limited. The ICUN Red List of Threatened Species has evaluated this species as ‘vulnerable’ due to the “commercially high value and growing demand for its fins, restricted nearshore habitat as well as its limiting life history characteristics”.

If you are out diving or snorkeling and see this elegant and fascinating creature, then make sure to grab a photo and relish in the moment of a rare sighting!

For more pictures of Guitarfish, check out Elasmodiver.com who kindly granted us use of the above photograph.

Lasting Effects of a Shipwreck

2010-03-04T08:03:00.003-10:00

text and photographs by Cristi Richards

Typical site at Rose Atoll dominated by coralline algae
(light pink).

Coralline algae or CCA typically dominate the reefs surrounding Rose Atoll, making up 50% - 75% of the benthic cover according to preliminary results of our 2010 surveys. Scleractinian or hard corals comprise another 5% - 30% of the substrate. At the start of each dive, we are greeted by a light pink landscape accentuated by the greens and reds of fleshy macroalgal genera and the browns, purples and yellows of various genera of coral. The coralline algae are a combination of several genera including Mastophora, Porolithon and Peysonnelia.

In general, coralline algae play many important roles in the ecology of a reef ecosystem. They are a food source for many reef inhabitants including parrotfish, sea urchins and mollusks. Coralline algae also act as a stabilizing component or ‘cement’ for the reef and several genera of coral larvae will selectively colonize patches of this algae.

Site of ship wreck at Rose Atoll.
Brown and darker areas are dead coral
and CCA covered by turf algae and
cyanobacteria.

In October 1993, a 135-foot Taiwanese longline fishing vessel ran aground at Rose Atoll, releasing 100,000 gallons of diesel and 500 gallons of oil into the surrounding waters, across the reef flats and into the lagoon. The initial spill killed large numbers of giant clams, urchins, sea cucumbers and the dominant benthic organism, coralline algae, as well as endangering the health of 12 species of migratory seabirds and the threatened green sea turtle.

However there is still damage occurring to the reef ecosystem, 17 years later. Although there are on-going efforts to remove metal wreckage, with 37.5 tons having been removed to date, there are still iron contaminants being released by the remaining portions of the vessel. When we surveyed this site yesterday, it was immediately obvious that the habitat was vastly different than those seen at other areas of the Atoll. The percent cover of coralline algae was up to 50% less than at other areas, with corals comprising less than 1% of the benthic cover. We also noted an increase in the occurrence of cyanobacteria and turf algae.

Cyanobacteria covering a
colony of Favia stelligera

The iron contamination continues to cause a cyanobacteria or blue-green algal, bloom that is detrimental to the health of both the coralline algae and the corals. The cyanobacteria compete for space with coral larvae by settling on the CCA in thick mats, thus blocking the larvae’s access to the CCA. The thick mat also blocks sunlight from reaching the CCA. In addition, strands of cyanobacteria that detach from the bottom can settle and develop directly on corals. The end result is that corals and CCA are smothered and eventually die, thus changing the overall benthic composition of the reef. The presence of the increased levels of cyanobacteria causes a physical and chemical environment that is not suitablefor the growth of the original reef inhabitants.

This scar at the site of the shipwreck can still be seen today as a reminder of how fragile these ecosystems really are. With continued surveys, this will be a valuable documentation of how long it takes areef to recover from a wreck such as this.

Rose Atoll, part 2

2010-03-02T23:11:00.005-10:00

by Kerry Grimshaw
photographs by Jean Kenyon

Exposed coralline algae at Rose Atoll

Our day began with a beautiful sunrise and light winds at Rose Atoll, which is one of the smallest atolls in the world and is diamond shaped. The outer reef slope around Rose is steep down to depths greater than 200 meters (~650 feet). The atoll also encompasses 2 small islets named Rose and Sand Islands. Perhaps the most outstanding feature of the atoll is the bright pink color of the exposed reef. The reef gets itís pink hue from the dominant crustose coralline algae Porolithon. This crustose coralline alage is one of the primary reef-building species at Rose Atoll.

Rose Atoll has a coral and fish community different from elsewhere in American Samoa. Currently the US Fish and Wildlife Service reports that there are 113 species of coral and about 270 fish species recorded at Rose. The atoll also supports the largest populations of giant clams, nesting seas turtles and rare reef fish species in the territory. In addition, humpback whales, pilot whales and various species of dolphin have been seen in the waters surrounding Rose Atoll.

Reefs dominated by coralline algae

The 2 islets are not without their own claims of importance. Rose Island is home to a grove of Pisonia trees on it, which is the only remaining Pisonia stands in Samoa. Rose and Sand Islands provide vital nesting habitat to the most important seabird colony in the region, including 12 federally protected migratory seabirds. Some of the birds that utilize Rose Atoll are the Red-footed Boobies, Greater Frigate birds, Lesser Frigate birds, Black Noddies, White Terns, Reef Herons and Red-tailed Tropic birds.

Since Rose Atoll is very remote and extremely unique due to its terrestrial and marine communities it provides an excellent place for scientific research. As such, our days spent at Rose Atoll are always a highlight of our cruise!

Rose Atoll, part 1

2010-03-01T23:34:00.015-10:00

By Kerry Grimshaw

Photograph by Jean Kenyon

This afternoon we began our transit to Rose Atoll which is about 240 km (130 nautical miles) to the east of Tutuila. It is often referred to as Rose Island or Motu O Manu (meaning “island of seabirds”) and is the only atoll in the US Territory of American Samoa.

Rose Atoll was first documented in 1819 by Captain Louis de Freycinet who named the isle “Rose” after his wife. It was later visited in 1824 by Otto von Kotzebue and in 1839 by Dr. Charles Pickering, as part of the US exploring expedition, who was likely the first scientist to visit the atoll. Rose Atoll has always been uninhabited except for a brief time in the 1860s when there was an unsuccessful attempt to establish a fishing station and coconut plantation by a German firm. In 1920 a concrete monument was erected on Rose Island by the naval governor of American Samoa to commemorate his visit and allow public access to the atoll. Later in 1941, President Roosevelt made the atoll a naval defense area, but it was never used for that purpose. Rose Atoll became a National Wildlife Refuge on July 5, 1973 and a Marine National Monument on January 6, 2009.

Photograph from noaa.coris.gov

The formation of coral atolls was first described by Charles Darwin during his 5 year voyage through the South Pacific aboard the HMS Beagle from 1831 to 1836. An atoll starts with an oceanic volcano in tropical seas. A fringing coral reef forms on the flanks of the volcanic island and grows upward as the island subsides. The fringing reef separates from the island forming a lagoon as the inner part of the reef begins to subside along with the volcanic island forming a barrier reef. The outer edge of the barrier reef continues to grow and remains near sea level. Eventually the island completely subsides below the ocean surface leaving the barrier reef surrounding a lagoon thus forming a coral atoll.

We are looking forward to the diverse ecological community and habitats that an atoll provides. Rose Atoll will be only the 2nd atoll that we've visited on this mission (the other was Johnston Atoll) and it will be interesting to see how the coral reefs of Rose Atoll differ from those around Tutuila Island.

Cool Critters of the Reef

2010-02-27T23:59:00.007-10:00

text and photographs by Erin Looney

One of the many benefits of conducting coral reef research is the cool critters we encounter almost every day. Whether it is something big, such as a shark, turtle or dolphin, or something small, such as a nudibranch, sea anemone or crinoid, these creatures are all amazing in their own way. Here are a few examples of what we're seeing. All of these organisms were seen in a reef environment between 10 and 20 meters (30 - 60 feet) deep. Enjoy!

Trapezia rufopunctata, Trapezid Crab

Amphiprion perideraion, Pink Anemonefish

Tridacna maxima, Giant Clam

Plerogyra sinuosa, Bubble Coral

A Visitor at Dawn

2010-02-26T08:07:00.000-10:00

by Cristi Richards

Flying Fox seen over Cockscomb, Tutuila (photograph by Benjamin Richards)

Preparations for each day of diving generally begin before sunrise, when a quiet, sleepy hush still envelopes the ship. This seemed especially appropriate when yesterday morning, just before sunrise, a silent, graceful silhouette was observed gliding behind the ship. It wasn't a bird but a flying fox or fruit bat.

There are three species of bats living in Samoa, two large fruit-eating bats and a smaller insect-eating bat, which are the only three native mammals in the Samoan Islands. These can seem odd to visitors coming from places where bats are small and generally hard to find or see. In Samoa the sight of a flying fox is a common occurrence. The bat following the ship this morning was one of the fruit-eating varieties which can attain up to a 3 foot wingspan and making it either a Pteropus samoensis (Samoan Flying Fox) or a Pteropus tonganus (Tongan Fruit Bat). While most bats are nocturnal, these bats can be seen throughout the day soaring on thermals or moving between roosting and feeding sites during the dawn and dusk hours.

Both species of bat consume a variety of foods including nectar, pollen, sap and the juice of fruits and leaves. Eating only the juice, the bat will chew on the fruit and press the pulp against the roof of it's mouth creating a pellet of dry pulp known as an ejecta. The ejecta is then spit out to make room for more pulp. This process makes it easy to determine where bats have been feeding and by analyzing the ejecta (commonly found on the hood of your car if you happen to park under a breadfruit tree).

The fruit bats found in Samoa also play an important role in pollination and seed dispersal, increasing the productivity of fruit trees transporting seeds to cleared areas. This aids the natural reforestation process. We are not sure how our flying fox visitor came to be sailing behind the Hi'ialakai instead of feasting in a breadfruit tree, but it was an impressive sight that caught the attention of everyone awake at that hour.

References:
Natural History Guide to American Samoa, 3rd edition, 2009. P. Craig, editor

Notes from a Coral Reef Microbiologist

2010-02-25T20:38:00.008-10:00

Collecting water samples

by Tracey McDole

Imagine that you are a scientist diving on a coral reef… what types of organisms would you choose to study? Many different life forms probably come to mind, including fish, invertebrates, and of course the corals. However, these are all macroorganisms (“macro” meaning large). In other words, these are organisms that can be seen with the naked eye. What you may not realize, is that an incredible diversity of life also exists at the microscopic scale. In fact, in one drop of seawater there are on average 1,000,000 individual bacterial cells! If that figure isn’t amazing then try one billion viruses per drop! That means that in just a few milliliters of seawater there are more viruses than there are humans on planet earth! Don’t worry, most of them are bacteriophages, viruses that only infect bacteria.

There are, however, some marine viruses that cause disease in reef macroorganisms. Did you know that corals get tumors, a growth anomaly that may be caused by viruses in the family Herpesviridae? Don’t get me wrong, in a healthy reef ecosystem, viruses and microbes play beneficial roles. The coral reef food web is structured so that energy and materials flow from the microbes to macrobes, and back again. Therefore, both viral and bacterial communities are essential components of any healthy reef system.

One of the biggest and most pressing questions that coral reef scientists are currently trying to understand is: How do the combined effects of pollution, overfishing, and climate change result in degraded coral reefs? One way to start is to determine if both groups of organisms (macrobes and microbes) function and interact differently on healthy versus degraded reef systems.

To answer this bigger question, we must start by asking relatively simple questions. How many bacteria and viruses are there on a healthy versus a degraded reef? Are the types of microbes and viruses inhabiting the water column above a healthy reef different from those inhabiting a degraded reef? The first question involves capturing the bacteria and viruses on a filter, staining the filter with a fluorescent-dye that binds to DNA, and finally visualizing the filter with a fluorescent light microscope. The result looks like the night sky! Luckily the microbes and viruses are counted by a computer program.

Microorganisms vs. Macroorganisms

So who’s there? Good guys or bad guys? Answering this question involves a technique called DNA sequencing. DNA from inside the viruses and bacterial cells is purified and the genetic material can then be replicated. When there are enough copies of the DNA, a machine literally reads the base pairs in the DNA sequence. If the DNA sequences match a known sequence in a master database, the microbe or virus that it came from can be identified. Typically, only a portion of the sequences actually “hit” something in the database. This means that the majority of microorganisms and their genes are still waiting to be discovered. But with each water sample we get closer to understanding this complex web of microscopic interactions on the reef.

Lilies of the Sea

2010-02-24T20:09:00.001-10:00

Crinoid or Sea Lily from American Samoa (photograph by Cristi Richards)

by Benjamin L. Richards

Today the benthic team recovered three Autonomous Reef Monitoring Structures (ARMS) which have been attached to the seafloor in Fagatele Bay National Marine Sanctuary, American Samoa, for the past two years. This smallest and most remote of all the National Marine Sanctuaries is also the only true tropical reef in the National Marine Sanctuary Program. Fagatele Bay, on the southwestern coast of the island of Tutuila is a small eroded volcanic crater which provides shelter for a wide variety of organisms that thrive in its protected waters.

After locating the dive site, we slipped over the side of the boat into crystal clear waters and descended to a sea floor covered in coral. We located the three ARMS easily and, after installing a new set of ARMS and a set of calcification plates which will be used to investigate the impacts of ocean acidification, we removed the old ARMS and brought them to the surface.

After returning to the ship, we spent several hours disassembling the ARMS and sorting through all the various creatures who had made it their home. The biodiversity was amazing. We found a host of crabs, snails, shrimps and a myriad of other tiny and amazing creatures. We also found our first crinoid.

Crinoids, or sea lilies, are echinoderms (relatives of sea stars and sea urchins) and have lived in the tropical oceans since at least the Ordovician period (~450 million years ago). Like sea stars and urchins, most crinoids are free swimming and feed by filtering small particles from the passing water with their feathery arms. Once the food is trapped by a sticky mucus on the tube feet, it is moved towards the mouth at the center of the body. It has been found that crinoids living in environments with a relatively low abundance of plankton have longer arms than those living in plankton-rich waters. This is presumably to increase the surface area where food can be trapped.

Finding a such a beautiful and delicate creature in the ARMS was exciting for members of the ARMS team as well as for those who stopped by the lab to glimpse the latest arrivals from the reef. The diversity of cryptic invertebrates being found is an exciting testimony to how much more there is to learn about reef ecosystems. As part of the Census of Coral Reef Ecosystems (CReefs) project of the Census of Marine Life, CRED is collaborating with international partners to deploy ARMS on coral reefs around the globe to establish biodiversity baselines and monitor changes over time.

Talofa Tutuila

2010-02-21T22:43:00.006-10:00

Aunu'u and Tutuila (left to right), photo taken by PIBHMC

By Kerry Grimshaw

After nearly a month into our cruise we have begun our work in the US Territory of American Samoa. We are conducting surveys around the island of Tutuila which is the largest and most populated of all the islands in the Territory. Tutuila has a land area of 141.81 km²(54.75 mi²) which is just slightly smaller than Washington D.C. As the third largest island in the Samoan Archipelago (Savaii & 'Upolu in Samoa are 1 & 2 respectively) it is distinctive in the South Pacific for having a large deep natural harbor.

As one of the most protected harbors in the South Pacific, Pago Pago became a point of contention when the United States gained exclusive use in 1872. However, both the British and Germans also had political and trade interests in Pago Pago. After about a decade of mounting tensions and a serendipitous cyclone, the 3countries negotiated in 1889 where Western (Independent) Samoa was ceded to the Germans, eastern Samoa went to the Americans, and the British were happy with German renunciation of Tonga, the Solomon Islands and Niue.

In April of 1900 eastern Samoa was formally annexed by the USA. Traditional rights were protected in exchange for a military base and a coaling station; however, Samoans became US Nationals, but not US citizens. Pago Pago became instrumental during World War II as the center of the Samoan Defense Group, which was the largest of the Pacific Defense Groups. As the war moved north and west, American Samoa became a strategic backwater. In the postwar era, American Samoa's military importance declined and in 1951, the Territory was transferred to the Department of the Interior, under whose jurisdiction it remains.

Until the 1960’s, American Samoa remained almost entirely traditional. After the modernization era, the subtle and restrained US presence was over. In 1977 the first elections were held for democratically elected leadership, replacing the leadership of appointed governors.

Pago Pago Harbor

Tutuila has a reef area of 36.2 km² (14 mi²) and is home to more than 140 species of corals. Tutuila's waters are protected by the 0.7 km² (0.3mi²) Fagatele Bay National Marine Sanctuary, as well as by the National Park of American Samoa, which covers the north-central part of the island and approximately 5 km²(1.9 mi²) of coastline. Tutuila is also unique because of its extensive banks that occur 1-9 km (0.6-6 mi) offshore. On these banks CRED has conducted camera surveys in previous years and documented the presence of corals and numerous species of fish.

We’ll be working in the waters surrounding Tutuila until March 2nd when we begin our transit to Swains Island. For those of you reading from the island of Tutuila you may see us as you are out and about during this time.

Corals, corals, everywhere ...

2010-02-18T22:25:00.000-10:00

by Bernardo Vargas-Angel

High percent coral cover and species diversity; that is what we encountered while working site TUT-09, located on the south-facing shores of Tutuila Island. It was a vibrant tapestry of texture and color; Montipora, Acropora, Pocillopora, Hydnophora, Coscinaraea, Leptastrea, Leptoria, etc; the list of coral genera was endless, and so was the number of individual colonies encrusting on the flat bottom.

The coral working-group of the Benthic Rapid Ecological Assessment (REA) team specializes in gathering data that pertains to the structural demographics of the coral populations. In other words we are interested in acquiring information about the different types of corals present on the reef, their relative abundance, as well as the sizes of the different colonies. Once collected, this information is later summarized and analyzed, and is made available to local, regional, and state resource managers. Armed with this information, these managers can make informed decisions pertaining to the administration and use of natural resources around the island.

The coral working-group collects the coral demographic data along two belt-transects, 25m in length by 1m width. Today, my dive buddy Erin and I were particularly challenged in getting our work accomplished at survey site TUT-09, not only due to the high numbers of coral colonies growing on the bottom, but also because we had wave and surge action which made it difficult stay focused on one portion of the bottom at a time. Nonetheless, after a long 85 minute dive, Erin and I emerged satisfied with the work we accomplished, and were pleased to have had the opportunity to investigate such a site.

Visiting the Hi'ialakai

2010-02-17T11:54:00.000-10:00

by Cristi Richards

On February 15, the NOAA Ship Hi’ialakai opened its doors and gangway to the American Samoa community in Pago Pago for an open house. Members of the public were invited to tour the ship and hear about all aspects of its operations from the Bridge to the Fantail. Participants were treated to a Bridge familiarization with an explanation of the electronics and maneuvering procedures, an overview of the deck machinery and how the small boats are launched for daily operations and hands-on demonstrations of the scientific aspects of the cruise including algal identification, the morphology of coral disease, fish survey techniques, towboard operations, and ARMS and invertebrate observations via a microscope. Crew and Scientists participating included ENS David Vejar, SS Gautano Maurizio, Chief Scientist Benjamin Richards, Oceanographer Oliver Vetter, Benthic Team members Molly Timmers, Cristi Richards, and Bernardo Vargas-Angel, Towboarders Kevin Lino, Jason Helyer, and Fish Team member Paula Ayotte.

Despite the rain and President’s Day, we had a modest turn out and were excited to see members of the public interested in what we spend so much time working on. It was especially wonderful to see the curiosity on children’s faces when learning about what they probably see every weekend on the beach. One set of children were particularly surprised when shown a slightly green, calcified, crunchy and segmented example from the local beach which is actually the green alga Halimeda. This alga is one of the primary sand producers in the area and a common sight on local beaches however many people might not identify it as a plant. The Towboard demonstration was also a highlight as the team had recent video footage from Howland and Baker Islands playing. The Towboard methods allow a large area to be covered and the footage gives the viewer the sense of flying over the reef. We are always excited to show off the ship and the work that we do. We are looking forward to the next import when we can again invite members of the public aboard what we’ll be calling home for the next 2 months.

Finding the lee

2010-02-12T18:50:00.002-10:00

by Benjamin Richards

Hurricane Rene tracks across Samoa

Our transit south from Baker Island to American Samoa has gone well and has been largely uneventful. That is, at least, until we began to feel the effects of hurricane Rene, which has been wandering around in the south Pacific. The storm first tracked east to the north of Samoa and then turned back to the west, this time to the south of Samoa. As Pago Pago, our intended destination is on the south side of the island of Tutuila, this southerly storm track did not bode well. Waiting to see how conditions would change, we slowed our southward course and eventually decided to delay our arrival in Pago Pago, to ride out the storm in the lee of the island of 'Upolu.

During our transit this morning we experienced stiff winds in the neighborhood of 40 knots and driving rain, but the good ship Hi'ialakai rode the seas well and handled beautifully. We are currently in the lee of 'Upolu, where the wind and seas are calm and a gentle swell rolls in from the east. We will bide our time here until the storm clears and plan to arrive in Pago Pago on the morning of 2/14, Valentine's Day.

Coral Species Diversity and Conservation Challenge in the U.S. Pacific Ocean

2010-02-10T20:35:00.002-10:00

by Jim Maragos, Ph.D.,Coral Reef Biologist, U.S. Fish and Wildlife Service, Honolulu & Member, Coral Specialist Group, Species Survival Commission, IUCN
photographs by Russell Moffitt

The Pacific Ocean supports the largest and among the oldest habitat for coral reefs, and the United States now manages the largest array of protected coral reefs in the world. Especially during the past century, coral reefs have been increasingly threatened by the activities of mankind, but now population growth, unmanaged fishing, and climate change will pose as more severe threats to coral reefs during the next century. Stony corals and coralline algae are the main life forms responsible for the biogenic growth and maintenance of reefs worldwide, yet we are only now focusing attention of the status of threats to these principal reef builders. Most reef corals consist of thin living animal tissues over a stony skeleton, and most are colonial and dependent upon single celled plants (called zooxanthellae) that live in their tissues for growth and nutrition. As such, these factors complicate efforts to define coral species and determining which are under threat and warrant special protection.

Scientific description of corals began with Linnaeus in 1758, and for most of the following century, definition of coral species relied on dead skeletons, written descriptions, and sketches. Although this approach has been successful for higher non-colonial animals such as birds, mammals and reptiles, corals altogether lack the prominent diagnostic features of these species such as eyes, noses, beaks, limbs, heads, tails, ears, faces, consistent coloration, etc. Moreover, the English language has mostly evolved in regions lacking corals, requiring Latin derived words as the basis for describing them, further confounding the understanding of the terms by which corals are separated into different species. Since 1850, photographs accompanied the published description of coral species, but virtually all of these were of the dead, cleaned skeleton of corals, with description of living tissues still relying on artistic sketches and written descriptions. As a consequence there were many more coral species described than what actually occurred in nature due to the lack of sufficient information to distinguish them.

Over the past several decades, scuba diving and guide books with colored photographs of living corals have helped many scientists learn coral species underwater where they live. Nevertheless, the colonial nature of living coral allows many to change their growth form to better adapt to differing habitats, and there are still concerns over which coral descriptions are the real species and which are “junior synonyms” of them. Over the past half century coral taxonomists have grappled over alternative means to describe individual species including numerical taxonomy of morphological features and immunoassay techniques to distinguish closely related species. However, these have met with limited success. More recently, molecular approaches that compare the DNA of different corals are showing great promise in determining which morphologically similar species have differing genomes and which corals with differing growth forms have the same genomes. As more “markers” are discovered on genes, there should be greater success in defining coral species. However, there will still need to be a strong relationship between consistent morphological-anatomical characteristics and molecular characteristics to resolve the coral species dilemma, and determine which are in greater need of protection.

Out of touch ... in the dead zone

2010-02-09T19:00:00.001-10:00

I have to apologize to all for our lapse in posts over the past few days. Our communication off the ship is handle via a connection to a satellite and we have been transiting through a "dead zone" near the equator for the past day or so. We have now crossed back into signal range and should be able to resume our normal posting schedule. Thanks to all for your patience and understanding.

Our transit from Baker Island to Pago Pago is going well and we are all looking forward to our continued operations in American Samoa.

El Niño and Coral Bleaching

2010-02-05T23:27:00.003-10:00

by Noah Pomeroy and Bernardo Vargas-Angel
photographs by Noah Pomeroy and Kara Osada-D'Avella

“I was sweating in my wetsuit!” “It was like diving in bathwater”… Such proclamations were common as everyone rinsed down gear after our first day of diving at Howland. Earlier that day, my fellow divers of the oceanography team, Oliver, Russell and Danny, popped up from their first dive and told me I’d be roasting in my 5mm wetsuit if I wore it on the next dive. Heeding their advice, I rolled backwards off our boat, “Steeltoe,” into the warmest water I’ve ever dived in. Learning to dive in frigid California waters while wrestling with half-inch-thick neoprene covering my body really made me appreciate being able to dive for an hour in swim trunks without so much as a chill. My SCUBA console gauge reported the water temperature at an exceptionally warm 86F (30C).

A subsurface temperature recorder
attached to the reef

Sure, we all knew it was hot, but we leave it up to our precisely calibrated instruments to tell us the detailed story of Howland’s water temperature since we last visited two years ago. During our dives that day, we recovered four subsurface temperature recorders (STRs) that we had attached to the Howland’s reefs two years ago. The deepest was installed at a depth of 126 ft, the shallowest was positioned at 23 ft. We installed four new STRs in place of those that we recovered at Howland so we may continue to monitor the in situ water temperature at this small isolated Pacific island. Recording temperature every 30 minutes, the high resolution data from the STRs clearly show its waters have been warmer that usual for the last 4 months. These elevated temperatures are likely due to the effects of the El Niño-Southern Oscillation (ENSO), a climate pattern that occurs on average every 2-7 years throughout the tropical Pacific. During ENSO, commonly referred to as “El Niño,” warm water from the western Pacific spreads eastward in the equatorial current. The name El Niño comes from Spanish "the boy" and refers to Christ as the warming period off the coast of South America typically begins in December, around Christmas time.

Such warming episodes have occurred for at least the past 300 years but strong events can have serious implications for the health of coral reefs. Although we all enjoyed the comfort of diving in Howland’s exceptionally toasty water, Howland’s coral may have a different take on the elevated water temperature.

Coral bleaching at Howland Island

During our first dives at Howland, we observed high levels of coral bleaching. Coral bleaching refers to the reduction in the intensity or complete absence of coloration within living coral. This reduction in color is due to loss of pigmentation, and/or the expulsion of the endosymbiotic single celled algae (zooxanthellae) that normally live within the coral tissue. This loss results in the white skeleton showing through the remaining translucent tissue. Bleached corals can appear pale, pinkish, bluish, or white as new fallen snow. Patterns of bleaching can vary, with only the upper surface or lower surface of the colony being affected. Bleaching can also vary along gradients as well as among different species, with some being more susceptible than others. Extensive bleaching has been attributed to exposure to increased water temperatures. However, bleaching is a generalized stress response and therefore high levels of ultraviolet radiation, salinity, turbidity, and sedimentation may also induce bleaching. Prolonged anomalously high water temperatures not only can result in widespread coral bleaching but can eventually cause the death of the coral.

During our surveys around Howland, we have observed bleaching affecting many coral species, with massive species appearing to be more resistant than branching and table corals. We have collected environmental and biological data pertaining to this event which is being compiled and analyzed to generate a peer reviewed publication.

Reef Biodiversity, an introduction:

2010-02-04T22:44:00.001-10:00

by Russell Moffitt and Molly Timmers

Coral reefs have been dubbed the rainforests of the sea due to their extraordinary biodiversity. They are among the most diverse and biologically complex marine ecosystems in the world even though they represent only 0.2% of the area in the ocean. Yet, the magnitude of their biodiversity is uncertain. Estimates of the number of coral reef species range into the millions, though mankind has only identified and described a small handful. Moreover, many coral reefs are threatened by anthropogenic and environmental stressors including climate change, ocean acidification, resource exploitation, marine debris, sedimentation, invasive species, and other factors. Because even the broad dynamics of coral reef decline and recovery are poorly understood, it is difficult to predict the long-term impacts of human activities on them. Without robust knowledge of coral reef biodiversity, detecting changes in reef assemblages and investigating causes of such change will be impossible. Developing universal sampling methods and protocols is therefore imperative to establish this necessary baseline against which we can make spatial and temporal comparisons in the future.

Due to the presence of long-standing taxonomic expertise and the relative ease in sampling them, fish, corals and some macroinvertebrates have been well documented. However, this is not the case with the lesser known and cryptic marine invertebrates which compose the majority of the species that inhabit coral reefs. The difficulty in extracting these small organisms from the reef matrix has hampered broad-scale diversity investigations. Thus, methods that can successfully sample the lesser known coral reef fauna need to be developed.

An ARMS unit attached to the reef
awaiting occupants

Autonomous Reef Monitoring Structures (ARMS) were developed by CRED in conjunction with the Census of Coral Reefs Project (CReefs) of the Census of Marine Life (CoML) to serve as a method to detect the cryptic fauna on reef systems. By mimicking the structural complexity of benthic habitats, they are designed to be colonized by an array of mobile and sessile invertebrates as well as crustose and turf algae. The ARMS contain 9 layers: a green mesh layer providing “habitat” for organisms such as polychaetes, sipunculids, and acorn worms (hemichordata); four open layers for sessile organisms such as sponges, bryozoans, bivalves, and tunicates; and four semi-closed layers that attract cryptic motile fauna such as galatheid and xanthid crabs, alpheid shrimp, and nudibranchs. Additionally, as sessile organisms colonize the structure, they create additional complexity and potential habitat for other organisms.

Divers intall an ARMS unit

Two divers install the ARMS on the seafloor by pounding stakes into the reef and then securing the ARMS unit to the stakes. Two 7 lb weights are also attached to each ARMS to help keep the unit in position during heavy currents or wave surge. Once installed, each ARMS unit remains on the sea floor for two years. ARMS were deployed at Howland and Baker Islands during ASRAMP 2006 and will be removed from the reef during this cruise. The species that have colonized the ARMS over the past couple years will be systematically assessed using both taxonomic and molecular genetic analyses in order to compare indices of cryptic biodiversity across diverse biogeographic and habitat gradients thereby facilitating the monitoring of changes in these assemblages over time.

To date, ARMS have been deployed widely in tropical seas across the globe. Current sites include Moorea, Australia, Reunion, Brazil, Hawaii, American Samoa, the Marianas Islands, Panama, Belize, Papua New Guinea, and the U.S. Central Pacific Islands. They will soon be deployed in the Cayman Islands, Puerto Rico, Indonesia, and the Seychelles. Data from the ARMS will be used to determine the degree to which the communities recruiting to these artificial structures are representative of the reef communities in which they are deployed. While NOAA conducts a broad suite of reef monitoring and observing techniques, the ARMS will provide insights into the components of the coral reef community that SCUBA divers cannot directly quantify.

A Little About Howland

2010-02-01T21:38:00.003-10:00

by Russell Reardon
photographs courtesy of the National Archives and US Fish & Wildlife Service

Three days of transit down ... one day to go. Our next stop is Howland Island, a low, flat, sandy bit of an island with a narrow fringing reef, positioned some 50 miles north of the equator and 1,600 miles southwest of Honolulu. Uninhabited and vegetated only by grasses, vines, and shrubs, the island provides important nesting and roosting habitat for hundreds of thousands of seabirds and shorebirds.

Howland sound familiar? Did you see the movie “Earhart” with Hilary Swank? (We just watched it here on the ship the other night.) Howland Island is most recognized as being the scheduled refueling stop-over that Amelia Earhart never reached on her ill-fated bid to fly around the world in 1937. But, there is more to it than that. Evidence suggests that Polynesians visited the island long before its discovery by Europeans. Although there is no freshwater source, these ancient mariners may have used the island as a resting or gathering place during their voyages across the Pacific. At least three whaling vessels visited or sighted the uninhabited island in the early 19th century before it was officially named Howland Island in 1842.

The American Guano Company claimed Howland in 1857 and guano mining began in 1861. Guano was mined by companies from both the US and Great Britain, and both countries claimed it as sovereign territory. All told, an estimated 85,000 to 100,000 tons of guano were removed between 1861 and 1890! Evidence of the mining remains today as large excavated basins and mounds of low-grade guano. When the guano deposits were exhausted, Howland was abandoned.

In 1935 in an effort to reinforce the US claim to the island, a rotating group of four alumni and students from the Kamehameha School for Boys in Honolulu was sent to colonize the island, establishing a permanent settlement known at Itascatown (named after the USCG Cutter Itasca which dropped them off and regularly worked the area).

In 1937, an airfield was built in anticipation that the island might eventually be used as a stop-over for a commercial trans-Pacific air route. Most notably, Howland Island was the scheduled refueling stop for Amelia Earhart and her navigator Fred Noonan on their flight between New Guinea and Hawaii. Though Earhart’s radio transmissions could be heard from Howland, Earhart and Noonan were lost en route. What exactly happened to them remains a mystery to this day.

In 1941, Howland entered World War II with a Japanese air attack on December 8, 1941, that killed two of the colonists and damaged the airfield. Two days later a Japanese submarine shelled what was left of Itascatown’s few buildings and a single bomber returned twice during the following weeks to drop more bombs on the rubble. The only two survivors of the attacks were finally evacuated at the end of January 1942. In 1943, Howland was reoccupied by the US Marines and became known as Howland Naval Air Station until May 1944. All attempts at habitation were abandoned after 1944, which was probably just fine with the multitude of sea birds that come to Howland. Howland Island was established as a National Wildlife Refuge in 1974. Visitation to the refuge is by special use permit only. As with Johnston Atoll (our previous stop) and Baker Island (our next stop), Howland Island and it’s environs are part of the Pacific Remote Islands Marine National Marine Monument, established in 2009 by President George W. Bush.

Like at Johnston, our US Fish and Wildlife Service partners will be camping on Howland Island during our 3 days there, surveying the land while we survey the surrounding waters.

Fish Tales

2010-01-30T22:56:00.000-10:00

by Kara Osada-D'Avella

For this first leg of the expedition, our fish team is made up entirely of women – but no fish about it, we are out to take on the seas and collect data no matter the conditions; sunny or rainy; rough or calm. Our team lead, Paula Ayotte, is on her third trip to these waters along with me (Kara Osada-D’Avella), Jonatha Giddens and Emily Donham. As reports of over-fishing worldwide have topped headlines, concern for the possibility of over-fishing occurring on coastal reefs has also been increasing. According to recent scientific reports, over-fishing on coral reefs may be as high as 36%, with many high-valued species facing the possibility of localized extinction.

Throughout our three-month cruise, researchers will have a unique opportunity to survey diverse locales ranging from the extreme remoteness of Howland and Baker Islands to heavily populated areas of American Samoa. Our data will also be combined with surveys from the Northwestern and Main Hawaiian Islands, Guam, and the Commonwealth of the Northern Mariana Islands to provide an overview of the status and trends of coral reef fish populations in US Pacific waters. Our fish survey method uses a stratified random design where our survey sites are chosen within three depth zones: shallow (1-20 feet), mid (21-60 feet) and deep (61-100 ft) and within each of three general habitat types; fore reef, back reef and lagoon. By using this type of method, we are able to get a holistic view of the fish assemblage at each island we visit.

This is my second trip to Johnston Atoll. During the previous expedition in 2008, high winds and rough seas kept us out of the water for all but two days of the six we had planned. This year the weather cooperated and we were able to survey each of the 5 1/2 days we were at Johnston, allowing us to see much more of the reef environment. I found fish populations at Johnston to be similar to my experiences in the Northwestern Hawaiian Islands. Unlike the Main Hawaiian Islands, we saw sharks on many dives with a maximum of 10 sharks on a single dive. We also saw many large black jacks and other apex predators which is a good sign. On my last dive with Jonatha we were privileged to jump in on a reef with hundreds of spawning blue-lined surgeons. For me it was a unique experience to be in such a large school of fish; something you just don’t get to witness very often in less remote areas.

Coral Disease

2010-01-28T22:54:00.002-10:00

by Bernardo Vargas-Angel

A notable increase in coral disease is one of the most recent concerns pertaining to the resilience of coral reefs worldwide, particularly in light of mounting natural and anthropogenic impacts. Acute diseases have resulted in dramatic coral loss and significant changes in community structure, diversity, and ecosystem function. For example, Acropora white band disease has been recognized as one of the major factors leading to live coral cover reductions of up to 98% in areas of the Florida Keys and the Caribbean. This loss of coral cover and associated phase-shifts in coral community structure has led to an increase in macroalgae cover and reduced rates of coral reef accretion.

For many years, the threat of coral diseases in the Pacific had been regarded as relatively unimportant based on limited impact sources, inaccessibility, and the spatial vastness of the region. However, increasing evidence indicates an escalating abundance and prevalence of disease throughout Pacific locations, including the Great Barrier Reef, the Marshall Islands, Palau, and the Philippines, as well as the Red Sea and east Africa. The 2002/2003 outbreak of white syndrome in the northern and southern sectors of the Great Barrier Reef, when disease levels increased 20- to 150-fold on outer-shelf reefs, was cause for great concern.

For most coral diseases, the lack of ecological and pathological data hinders a clear understanding of disease causation, virulence, and transmissibility. Moreover, the association between disease and environmental stress still remains largely unknown. Current research supports a connection between environmental deterioration and diminished coral immune capacity, and thus, environmental stress could influence coral disease by altering host/pathogen interactions. Because coral diseases may act synergistically with other stressors, there is reason to believe that management practices may be able to, at least in part, influence the impact of disease.

During this expedition, coral biologists are surveying for coral disease along twenty five meter transects and comparing the results to data from previous years and other areas of the pacific. Data collected by the scientific crew are pivotal to long-term biological and oceanographic monitoring of U.S Pacific coral reef ecosystems, including the assessment and evaluation for coral diseases.

Concerning Corals

2010-01-28T07:57:00.002-10:00

by Jean Kenyon and Erin Looney
photos by Benjamin Richards and Jason Helyer

Stony corals (Class Anthozoa, Order Scleractinia) are marine invertebrates that secrete a calcium carbonate skeleton. Stony corals can be hermatypic (significant contributors to the reef-building process) or ahermatypic, and may or may not contain endosymbiotic algae called “zooxanthellae”. The largest colonial members of the Scleractinia help produce the carbonate structures known as coral reefs in shallow tropical and subtropical seas around the world. The rapid calcification rates of these organisms have been linked to the mutualistic association with the zooxanthellae, found in the coral tissues. Massive and branching stony corals are the major framework builders of shallow tropical reefs. Some stony corals occur in deep water and are azooxanthellate (they do not contain zooxanthellae), but these deep water corals typically do not form extensive reefs. Corals are arguably one of the most important components of the coral reef system, providing substrate for colonization by benthic organisms, constructing complex protective habitats for myriad other species, including commercially important invertebrates and fishes, and serving as food resources for a variety of animals.

While at Johnson Atoll we are collecting data on corals that will tell us more about species abundance and distribution, size class distribution, and disease. Each site we visit differs in terms of species dominance, the relative abundance of coral, and the health of the corals present. Many factors contribute to this, including the location of the reef (whether it is a backreef, forereef, or in a lagoon), wave intensity, and its closeness to human population and associated pollution. One would expect that reefs as far removed as Johnston would be pristine, healthy, flourishing environments, but even these are subject to disturbances such as hurricanes, marine debris, and pollutants introduced to the environment throughout history. Especially in the Pacific, many island which are not currently inhabited, have had sizable human populations in the past. Johnston is one of these and, we find a relatively high prevalence of coral disease at Johnson Atoll compared to other islands.

Although these reefs may not be as pristine as we might hope, they are by far some of the most beautiful and deserve our best efforts in understanding the dynamics that keep them thriving. Every day we are amazed by something new, something we've never seen before (possibly that no one has seen before), and are reminded of why we are out here, trying to learn more about this complicated and amazing environment.

All About Algae

2010-01-26T21:53:00.001-10:00

text and photos by Peter Vroom

Despite the nonflattering images of “pond scum” many people often associate with algae, marine algae (or macrophytes) have proven themselves to be among the most diverse, most ecologically important, most prevalent, and most beautiful organisms present in tropical reef systems. Their importance to the ecosystem is staggering: algae form the base of the food chain, occupy much of the available substrate, and help to oxygenate the water, allowing animal life to thrive. Additionally, without microscopic symbiotic algae living in healthy coral tissue, most corals would be unable to survive – a scenario that is becoming all too real as coral bleaching events (processes where stressed corals expel their algal symbionts) become more common.

Although large, fleshy algal forms are often the most recognizable floral components on reefs, tiny turf algae and crustose coralline red algae are also extremely prevalent and play significant roles in the ecosystem. Turf algae are the first to colonize vacant substrate and cover essentially every nonliving hard surface on the reef. Turf algae are also among the most important food source for herbivorous fish and invertebrates. Relatively fast growing crustose coralline red algae act as a glue that cements together loose components of the reef system, and serve as a settling surface for larval invertebrates and other algae. Without crustose algae holding everything together, much of the reef would be washed into deep water or onto shore during heavy winter storms.

Clearly, without algae there would be no tropical reef ecosystem, yet marine algae are among the least studied and least understood organisms on the reef. More research is sorely needed to catalog and quantify the species that are present on reef systems around the Pacific, and ecological studies are necessary to examine the role of these critical plants in reef ecosystems.

To accomplish these objectives, CRED is studying tropical reef algae to address the following questions:

What is the best way to quantify algal functional groups (macroalgae, crustose coralline algae, turf algae) in tropical reef settings?
What species are present in each island ecosystem and in what quantity?
Do changes in algal populations serve as a good environmental indicator of reef heath?
How do algal diversity and abundance change over time?
Can biogeographical hypotheses be formulated about algal dispersal and evolution using qualitative and quantitative data from island groups around the Pacific?

A modified Rapid Ecological Assessment technique that incorporates the use of digital cameras and photoquadrats is our primary field method, which we will be employing on this cruise.

Our First Days at Johnston

2010-01-25T21:47:00.009-10:00

by Benjamin Richards
photos by Kevin Lino, Kara Osada-D'Avella, and Russell Moffitt

Our first two days at Johnston Atoll have been spectacular. In years past we have arrived at the atoll to find howling winds and pounding seas which have kept us from surveying large sections of the exposed forereef areas along the north. This year a gentle swell has been breaking along the northern reefs as gentle breezes come in from the south. We can only hope the weather continues to hold.

Our first half day at the atoll was a shakedown day, which each of the teams used to kick off the "rust" that had built up after several months out of the water. While all are experienced divers, several of the teams have not worked together before and it usually takes a dive or two before they meld into the well oiled machine we see by the end of the expedition.

The towed-diver team started off their surveys along the western forereef where we often see large numbers of grey reef sharks. Sure enough, there they were as soon as we splashed into the water. See sharks out here is a good sign and we are happy each time we see these apex predators which tend to indicate a fairly intact food chain and a healthy reef system.

Our Oceanography team has been able to recover and install a number of instruments which measure sea surface temperature as well as a number of other oceanographic variables during their two year deployment. They were also able to install several calcification plates which are a new deployment for us. These small plates are being installed at various locations around the pacific during this expedition. They will be recovered after two years at which time scientists will measure the amount of calcification which has taken place. By comparing measurements from various areas over time, we may be able to get a better understanding of ocean-acidification, one of the many threats facing these magnificent reefs.

We were also able to drop off our US Fish and Wildlife Service partners on the main island where they will spend the next few days surveying the local bird, turtle, and other populations. We look forward to their report when we pick them up before heading south to Howland Island.

Johnston Atoll – extreme isolation

2010-01-23T20:42:00.011-10:00

by Beth Flint and Lee Ann WoodwardBiologists, U.S. Fish and Wildlife Service

Tomorrow we will arrive at Johnston Atoll, a remarkable place due to its extreme isolation in the largest ocean in the world. This tiny spot in the Pacific is critically important to a community of organisms that need shallow water or land to live during at least part of their life cycle. Johnston is the only emergent land in approximately 450,000 square miles of deep ocean. Thus organisms, such as seabirds like the Sooty Tern or the Red-footed Booby, that can forage at sea but need to breed on land or organisms such as Green Turtles, that rely on benthic algae for food, converge at this lonely atoll. Our jobs during the terrestrail portion of this visit are to estimate population sizes of nesting seabirds, identify and map plant species, and survey and monitor some of the remnants of various human uses of Johnston through the years.

President Calvin Coolidge recognized the atoll’s importance as a wildlife site and designated Johnston Island a National Wildlife Refuge back in 1926. In 1934 President Roosevelt added a military mission to the area and for the next 70 years the government used the atoll in a variety of capacities; as a base during Viet Nam, for the testing of nuclear weapons, and for the storage and disposal of chemical weapons. During the 1950’s and 1960’s there were as many as two thousand people living at Johnston. The main island at Johnston was originally about 64 acres, however, it was enlarged in various dredge and fill operations to its present size of about 633 acres. In addition to enlarging the existing islands, the military also created two new islands, North (Akau) and East (Hikina). The dredging destroyed some of the extensive coral reefs but much remains. The military has ended their mission at Johnston and departed the atoll in 2004 after several years of clean-up activities. Now Johnston has been returned to the wildlife that had it in the beginning and where there once were buildings, seabirds are again.

In January of 2009 President George W. Bush expanded protection of the waters around Johnston Atoll out to 50 miles as part of the new Pacific Remote Islands Marine National Monument.

Fifteen kinds of seabirds are once again nesting in great profusion at Johnston, in shrubs, on the ground like these Sooty Terns, and underground in burrows and rock crevices. The thing they all have in common is that they feed hundreds of miles out to sea but come here to lay their eggs and feed their chicks.

Heading out to sea

2010-01-21T20:27:00.000-10:00

by Benjamin Richards

Our date of departure has finally arrived. We cast off lines at just after 1:00 this afternoon and are now steaming southwest towards Johnston Atoll. We have a stiff breeze and a following sea which makes the ship roll gently back and forth over the waves. The past few weeks have been exhausting and that, combined with the steady rocking of the ship has sent most of the science party to their bunks for some much needed rest. Tomorrow we start in early on our shipboard preparations with an overview and re-familiarization of our small boats at 0800 (8:00 am) followed by our standard suite of safety drills and pre-dive medical exams. Once those are complete, its time to get to work on the final phase of gear preparation before our arrival and Johnston.

Getting ready to go

2010-01-20T15:51:00.000-10:00

As our date of departure draws closer, each of the research teams is hurrying to finish their final preparations, organize their equipment and get it loaded aboard the Hi'ialakai. A steady stream of crates, pallets, Action packers, Pelican Cases, and 5-gallon buckets can be seem making their way from laboratories, to pickup trucks and then up the gangway and into the ship. Fuel trucks pass to and fro, cranes are lifting the heavy equipment from the pier to the ship, and the electronics technicians are running the last of the cables to connect the various computers and other pieces of equipment used to collect a variety of different measurements while we are underway. Piles of equipment appear in various locations and then disappear almost as quickly as they appeared. There is a constant flurry of activity and it looks like we might just get underway as scheduled.

Who are we and what do we do?

2010-01-15T17:10:00.003-10:00

by Benjamin Richards

This year we will be sailing with 22 scientists from NOAA Coral Reef Ecosystem Division and the US Fish and Wildlife Service. We are a multidisciplinary team of researchers who study the oceanography, fish, coral, algae, invertebrates and birds that live in and around the remote reefs and atolls of the U.S. Pacific Islands. Our main objective is to continue monitoring for natural or anthropogenic (human-induced) fluctuations in the reef communities and to document the range of species (or biodiversity) that exists in various reef habitats. As our data set grows we are also working to identify patterns of habitat use and species' interactions. During this research cruise, teams of divers will be surveying the reef communities, recording species abundance, diversity, and spatial distribution for all four of these key components of the ecosystem. Our US Fish and Wildlife Service colleagues will be going ashore on various islands to study and monitor the local bird and sea turtle communities.

During the cruise we will be conducting three main kinds of SCUBA surveys: towed-diver surveys, Rapid Ecological Assessments (REAs), and Stationary Point Counts (SPCs), each of which is designed to gather information on a different part of the reef community. Biological data from these surveys can be analyzed in the context of oceanographic conditions and benthic habitat maps to help us understand how coral reefs function as an interconnected ecosystem.

Over the past 10 years, our main research objectives have been to:

Document baseline conditions of the health of coral reef living resources (fish, coral, algae, and invertebrates) in the U.S. Pacific Islands.
Refine species inventory lists of these resources for the island areas.
Monitor these reef resources over time to quantify possible natural or anthropogenic impacts.
Document natural temporal and spatial variability in the reef resource community.
Improve our understanding of the ecosystem linkages between and among species, trophic levels, and surrounding environmental conditions.

We hope you will join us to learn more as we continue our explorations of this amazing world beneath the waves ...