Abundance of calanoid copepods found Guaymas Basin deep-sea vent field from R/V Atlantis II AII-112-28 in the Guaymas Basin from July 1985 (Vent Benthos project)

<p>Zooplankton from the Guaymas Basin deep-sea vent field were collected with a 1 m^2 MOCNESS to examine the distribution of total standing stock, taxonomic composition, size-frequency distribution of zooplankton, and the species composition of calanoid copepods. Low altitude ( similar to 100 m above the bottom) horizontal tows along and across the axis of the basin's southern trough, and oblique tows from the bottom of the basin ( similar to 2000 m) to the surface were made. Total biomass in near-bottom samples (range: 13-46 cc/1000 m^3) was only about a factor of 10 lower than in the upper 100 m. Of the 67 species of copepods identified in two samples taken on low altitude tows, only 15 occurred in both samples. Many of the species in this relatively diverse community remain to be described. Larval and post-larval forms of benthic clams, gastropods, polychaetes, and crustaceans associated with the vents were collected 100-200 m above the southern trough, indicating the post-larvae may play an active role in dispersal of hydrothermal vent species.</p>