INTRODUCTION

Summary of Findings

Map of Northwest Hawaiian Islands. Click on the image to open a larger version.

The Hawai‘i Institute of Marine Biology has completed three sampling cruises to the Northwestern Hawaiian Islands since the research partnership was initiated in April, 2005. The most recent cruise aboard NOAA Ship Hi‘ialakai occurred during May – June, 2006. Preliminary results of the fourth quarter of research are presented here.

Population structure across the Hawaiian Archipelago does not fit a simple isolation by distance model, and broad-scale generalizations based on oceanographic currents are poorly supported.
Closely-related species with similar ecology and reproductive biology, such as opihi and hermit crabs appear to have significantly different patterns of gene flow.
At French Frigate Shoals, tagging the large predatory fish ulua and monitoring their movements has revealed that these animals generally remain within a small daytime home range. Yet, every full moon during the summer months, Ulua at FFS travel up to 30 kilometers to congregate at Rapture Reef, a preferred spawning site on the south side of the atoll.
The use of satellite transmitters has provided new information on the movements of tiger and galapagos sharks. Both species were found to range from the ocean’s surface to depths of 680 meters; that’s over 2,200 feet below the surface, the length of about seven football fields.
The squirrelfish Myripristis berndti shows high genetic connectivity across the Hawaiian archipelago, indication that this species forms a single widespread population.
Acropora white syndrome, a coral disease afflicting giant table coral, was found to be highly virulent. Researchers marked 41 infected coral colonies in 2005 and returned a year later to find 97.6% of the infected colonies suffering partial to complete mortality from the disease.
Johnston Atoll exhibited a higher occurrence of Acropora white syndrome than French Frigate Shoals and may prove to be the pathway from which the disease arrived at FFS. One reef (Donovan’s Reef) at Johnston Atoll showed a dramatic decline in live coral cover in 2006 (~5%) as compared to visual surveys in 2001 and 2003 (~80%).
Healthy Porites compressa (finger coral) and Porites lobata (lobe coral) harbor specific bacterial communities with little overlap between the two coral species.
A particular genetic type of coral-associated microbe is absent from all Northwestern Hawaiian Island samples of finger coral and lobe coral studied to date, but is present in all Kane‘ohe Bay finger coral and lobe coral samples examined thus far. Continuing research seeks to reveal this microbe’s possible ecological function.
There appears to be a correlation between disease susceptibility and colonies of giant table coral that harbor a specific type of dinoflagellate symbiont. Preliminary findings reveal that colonies harboring clade A Symbiodinium are more susceptible to disease. Continuing research will confirm whether this association may be relied upon as an indicator for disease susceptibility.
There appear to be multiple species of the invasive coral Carijoa in Hawai‘i, contrary to previous reports that it was introduced from one source.
The few alien species known from the NWHI are restricted to the anthropogenic habitats at Midway Atoll and French Frigate Shoals. Only one, the hydroid Pennaria disticha has spread extensively in the NWHI but neither this or other species has exhibited invasive characteristics at this time. Populations of alien marine species that have already colonized areas of the MHI represent the most likely source of invasive species in the NWHI based on the proximity and pattern of ship movements associated with the MHI.
Mapping data from various sources was integrated into a single framework which can be utilized to produce meaningful ecological insights for the assessment and monitoring of the Monument.
An Index of Biological Integrity (IBI) for reefs throughout the Hawaiian Archipelago was developed using a relatively small number of biological indicators. Subsequent evaluation of the IBI supported its viability as a management tool.
The greatest threats to the NWHI are global climate change effects and marine debris, while fishing and other locally-based activities result in comparatively less impact, indicating that the Monument should focus on mitigating these extra-boundary threats to preserve the ecological integrity of the NWHI.
NOAA IDEA Center awarded $75,000 to HIMB (and partner NWHIMNM) through the Pacific Region Integrated Data Enterprise (PRIDE) program for an integrated data visualization website for the HIMB-NWHI Coral Reef Research Partnership.
HIMB performed a preliminary assessment of vessel traffic patterns in the Northwestern Hawaiian Islands and identified a potential hot spot of activity between Pearl and Hermes Atoll and Lisianski Island.
An overview of the HIMB-NWHI Coral Reef Research Partnership has been incorporated into the HIMB Continuing Education Program which hosts tours for 6,000-plus community members annually.
The NWHI Outreach and Education Program successfully competed for a NOAA Office of Education MiniGrant totaling $100,000.
For the first time, mini-documentaries were created onboard the NOAA Ship Hi‘ialakai during the May-June 2006 research cruise as an outreach tool using “podcast” technology (links to the NWHI Multi-agency Educational Project Website).

The pages linked to in the navigation sidebar (left) provide detailed descriptions of the research progress. For a list of titles and authors, see the Table of Contents.

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