Highlights

Cruising for Deep-Sea Coral in Alaska

NOAA’s Deep Sea Coral Research and Technology Program wrapped-up the first cruise of the three year Alaskan field research initiative this week. The cruise from Seattle to Kodiak, Alaska allowed scientists to map and study four sites in the Gulf of Alaska where it’s believed there are Primnoa coral thickets. (see photo)

We were able to identify these sites based on high rates of coral bycatch reported in the annual NOAA Fisheries sablefish stock assessment, which usually signal the presence of dense thickets or groves of coral.

This mapping cruise sets the stage for cruises in 2013 that will use deep-diving, remotely operated vehicles to verify the location of red tree coral (Primnoa pacifica), black coral groves, and bamboo coral groves. We also hope to estimate Primnoa population size and collect samples for genetic analysis.

Deep-sea coral and sponges are widespread throughout most of Alaska’s marine waters. In some places, such as the western Aleutian Islands, these may be the most diverse and abundant deep-sea coral and sponge communities in the world.

As habitat for many different and important species of fish in Alaska, deep-sea coral and sponge ecosystems are vulnerable to the effects of commercial fishing activities. Because of their biology, they may also suffer impacts from climate change and ocean acidification.

The vast majority of Alaska’s continental shelf and slope has not yet been surveyed for deep-sea coral and sponge abundance. Mapping and locating these communities may help to predict the locations and types of human activities and climate impacts that may affect these important ecosystems.

The mapping cruise is being conducted in partnership with NOAA’s Coast Survey and the West Coast and Polar Regions Undersea Research Center of the University of Alaska, Fairbanks.

Posted June 18, 2012