Deep-sea Cruises 2010 - Cruise 1
Cruise Log: 9/23/2010
Martha Nizinski and Jennie McClain-Counts
|Scientists rig the multicore in preparation for deployment. - click to enlarge|
Four days into the cruise we continue to have good success with our sampling. Most of the gear has been deployed successfully and has collected specimens that will be utilized for multiple objectives on this cruise. Many field sampling techniques are being utilized to provide us the data necessary to characterize the area as a whole. For example, a conductivity-temperature-depth profiler (CTD) collects data on the salinity, temperature, and dissolved oxygen content of the water column. The CTD is also equipped with Niskin bottles which collect water samples. These water samples will be analyzed to determine levels of aragonite saturation. A multi-corer was deployed to collect sediment samples and the associated infauna. This piece of gear, however, has not been successful so far on this cruise. But we will keep trying! Larger organisms, such as fishes (scorpionfish, hakes, rattails) and invertebrates (shrimps, galatheid crabs, seastars, squids) were collected on the bottom in areas adjacent to and away from the deep coral habitat using an otter trawl.
|Today's catch: sea cucumber and a pencil urchin. - click to enlarge|
As the otter trawl moves along the seafloor, it collects anything in its path. Besides the animals we are targeting, we have also collected some interesting objects. The most unusual find was a whale tail; the most disappointing one was trash. The ROV is our primary sampling gear used to examine and sample the deep coral habitat. The ROV collects video, digital still photographs and is able to collect specimens using a suction sampler and a manipulator arm. All data collected by the ROV helps us characterize the coral habitat and make comparisons between coral habitats and those habitats away from the corals. We will address several questions including differences and similarities in the assemblages of animals that occur in these very different coral versus non-coral habitats, as well as the trophic dynamics of these different assemblages, and the connectivity between these habitats. Today we are moving to a different site, about five miles away from where we have been working. Stay tuned to what we find next.
|Sometimes when we trawl, we pick up some surprising items from the sea floor. This trawl collection included a whale tail with bone and soft tissue still intact. - click to enlarge|