About the Expedition
On January 21, 2010, scientists from the Coral Reef Ecosystem Division of the NOAA Pacific Islands Fisheries Science Center (CRED/PIFSC), along with visiting scientists from the Hawaii Division of Aquatic Resources, Scripps Institution of Oceanography, San Diego State University, the US Fish and Wildlife Service, and local agencies in American Samoa, departed on a three month expedition to Johnston Atoll, Howland and Baker Islands, American Samoa, Jarvis Island, Palmyra Atoll, and Kingman Reef aboard the NOAA Ship Hi'ialakai. This is the fifth biennial Pacific Reef Assessment and Monitoring Program (Pacific RAMP) expedition to American Samoa and the seventh to the Pacific Remote Island Areas. The expedition is sponsored by NOAA's Coral Reef Conservation Program (CRCP) and is divided into three segment sequentially led by Chief Scientists Benjamin Richards, Rusty Brainard and Jamison Gove.READ MORE...
The strategic goal of this research is to improve scientific understanding of coral reef ecosystems throughout the Pacific, and serve as the basis for improved conservation and resource management. The recent designation of the Pacific Remote Islands Marine National Monument highlights the importance of this research.
With their extremely isolated location, many of the Pacific Remote Island Areas host a vibrate marine ecosystem. Previous Pacific RAMP cruises have documented relatively high coral cover and diversity; and high densities of large-bodied reef fish including large numbers of apex predators such as Grey Reef Sharks (Carcharhinus amblyrhynchos) and Scalloped Hammerhead sharks (Sphyraena lewini). Many of these apex predators are rare near human population centers. AS in previous years, this Pacific RAMP cruise will perform a suite of standardized multi-disciplinary methods which include Rapid Ecological Assessments (REA) for fish, corals, other large invertebrates, and algae; towed-diver surveys for large-bodied fish and habitat composition; and oceanographic studies, which include the measurement of conductivity, temperature, and density of the water column (CTD casts); water sampling; and deployment of sea-surface temperature (SST), subsurface temperature recorders (STR) and acoustic doppler current profilers (ADCP). Scientists will also be deploying Ecological Acoustic Recorders (EARs) to learn about changes in the presence and activity of marine mammals, fish, crustaceans and other sound-producing marine life when researchers aren't there to record it otherwise. Autonomous reef monitoring structures (ARMS) will also be deployed as part of the CReefs project. ARMS are simple, standardized collecting structures designed to roughly mimic the structural complexity of reef habitats. They allow for the identification of small, hard-to-sample, but ecologically important cryptic invertebrates. ARMS are being utilized throughout the Pacific and globally to systematically assess spatial patterns and temporal changes of biodiversity. Use of the EARS and ARMS are an exciting addition to RAMP data collection efforts.Follow along below to learn more about where we are going, what we are seeing, and what we have found ...
Saturday, January 30, 2010
Thursday, January 28, 2010
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.
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.
Tuesday, January 26, 2010
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?
Monday, January 25, 2010
photos by Kevin Lino, Kara Osada-D'Avella, and Russell Moffitt
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.
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.
Saturday, January 23, 2010
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.
Thursday, January 21, 2010
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.