Counts of Protobranch bivalves collected in a series of epibenthic sled samples taken on R/V Endeavor cruise EN447 in the Western North Atlantic (34-39N, 68-70W) in 2008 (ENAB project) (NCEI Accession 0277825)

Acquisition Description:
Using an epibenthic sled, sampling was conducted at 25 stations along a transect from south of Cape Cod to near Bermuda and ranging in depth from 1000 to 5200m. After samples were brought on board, the mud was sieved (1mm mesh) using cold (2-3 degrees C) seawater and the bivalves and gastropods were picked from the samples, identified to genus or species and the first 20-30 individuals frozen (-80) in individual 1.5 ml tubes with any additional individuals placed in ethanol in a common station tube and then stored at -80. All other taxa were placed unsorted in 95% ethanol and are now stored at 4 degrees C. Because the initial sorting was done at sea under less than ideal conditions, the investigators resorted the samples under a microscope in the lab. So far, over 2600 protobranchs distributed among 27 species have been collected.

Sampling success was good, although somewhat sporadic, especially early in the cruise. The investigators used 2 different sleds - a heavy version with closing door and a lighter version where the doors remained open on ascent. The heavier sled was used for the first 12 samples. Because the collections from the heavier sled were less than expected (based on previous epibenthic sled samples of this area). the lighter sled was used for the remainder of the cruise. The lighter sled usually returned with much better samples, although this could also reflect the investigators' increased experience in sampling later in the cruise.

Samples are currently stored at UMass, but will be moved to the MCZ at Harvard for more permanent storage and curation.