H-186

Expedition EURYDICE, Leg 7, Philippine Trench

10.6083° N
126.61° E

9604.0 m

-

free-vehicle baited trap

R/V T. Washington

R.R. Hessler

Robert Hessler

formalin sw

dry

-

Verbatim date: Feb 1975. All data from Hessler et al. 1978: https://www.sciencedirect.com/science/article/pii/0146629178905854?via%3Dihub. "In February 1975, leg 7 of Expedition EURYDICE on board the R.V. Thomas Washington was devoted to the study of benthic communities in the axis of the Philippine Trench at depths greater than 9500 m." "Station H-186, 10 '36.5'N, 126 36.6'E, 9604 m. The designation "T' or 'B" in the subtrap column indicates whether the subtrap was in the top or bottom layer, respectively." "The present study concentrated on two ponds. The northern pond (centered at 10'36.5'N, 126~37.5'E) was about 8 km long, 6 km wide, and about 9605m deep. The southern pond (centered at 9°02.0'N, 127°03.5'E) was smaller and deeper, approximately 6.4 km long by 4.2 km wide, and about 9806 m deep. In both ponds the surface sediment was a loose brown clay." "The baited trap consisted of 16 Nalgene wide-mouthed, 2.1-liter bottles fastened to a framework in two layers of eight. In each layer the bottles were radially arranged, with the mouths facing inward. A plastic funnel with the neck removed was inserted into the mouth of each bottle. The mouth of the funnel was covered with galvanized screen of 12.7-, 6.4- or 3.2-mm mesh. The funnel openings varied from 8 to 33 mm and were paired randomly with the various screen sizes. Each bottle contained one to four small pieces offish for bait. Small holes (< 1 mm) were punched in the bottom of each bottle and funnel to ensure the circulation of water so the bait odor would spread. The trap hung approximately 1 m above the bottom. As soon as the traps were retrieved, the captured organisms were fixed in 4% buffered formaldehyde and later preserved in 80% ethanol." http://www.rvdata.us/catalog/ERDC07WT, "1975-02-21 Cebu, Philippines to 1975-03-19 Apra, Guam"