About Student Connection Previous Cruises FAQs Current Cruise Plan(PDF) Next Cruise Plan(PDF) Cruise Schedule Ship Information NOAA Fisheries Honolulu Laboratory For More Information Privacy Policy
Highlights from TC 02-06 Hawaiian Monk Seal Forage Research
Aloha from the Townsend Cromwell!
The NOAA Ship TOWNSEND CROMWELL is currently working near Tern Island on French Frigate Shoal and other banks in the Northwestern Hawaiian Islands. We are conducting dive operations, trapping, trawling, camera tows, and fish counts and collections to support Benthic Habitat research. Hawaiian Monk seals feed on bottom dwelling fish and invertebrates. Understanding the benthic habitat of Monk seal forage grounds is an important step in monitoring the health of the population of this protected species.
This busy cruise includes mixed gas diving using
trimix (air, helium, and oxygen), as well as scuba diving using nitrox (oxygen fortified air), and air. Because some
dives will be as deep as 180 feet, we have a recompression chamber aboard so that we will be capable of treating
decompression illness in the unlikely event that a diver falls victim to "the bends". NOAA diving is conducted according
to strict guidelines with layers of safeguards designed to prevent decompression sickness. The recompression chamber, two
trained chamber operators, and a Dive Medic on board add a level of safety commensurate to deep technical
diving.
During the deep dives, the divers recover disc shaped artificial rocks that were deployed by
the ship last year. These fake rocks mimic talus slabs that lay on the bottom and provide hiding habitat for eels,
fish and other forage species. In the way that bears turn over rocks and logs to look for food, Hawaiian Monk seals flip
talus slabs over hoping to find food. The artificial rocks are instrumented so that each
time the rock is flipped,
the movement is recorded along with the time and date. The electronic rocks are deployed in groups at accurately recorded
positions so that they can be easily found next year. One electronic rock in the group will also have a temperature
recorder and a sound emitting pinger to further increase the chances of locating the group when its time to retrieve
them.
We will continue to dive, trap, and trawl until the 24th when we will stop by Tern Island to pick up field biologists and transport them back to Honolulu.