On the midwater fish faunas of Gulf Stream rings with respect to habitat differences between slope water and northern Sargasso Sea
Jahn, Andrew E.
MetadataShow full item record
Northern Sargasso Sea
KeywordFishes; Atlantis II (Ship : 1963-) Cruise AII71; Atlantis II (Ship : 1963-) Cruise AII85; Chain (Ship : 1958-) Cruise CH110; Chain (Ship : 1958-) Cruise CH111; Knorr (Ship : 1970-) Cruise KN35; Knorr (Ship : 1970-) Cruise KN38
Forty-three 1000-in oblique Isaacs-Kidd midwater trawl collections were made on six cruises. In most cases, these were accompanied by 1500-m hydrocasts and plankton tows to 800 m. The fish collections comprise 19,400 specimens in 129 species, from Slope Water, Gulf Stream, Northern Sargasso Sea, and four cold-core rings. Temperature, salininty, oxygen, phosphate, and zooplankton biomass information accompany the collections. A model predicts that expatriate populations of Caribbean species can be maintained in the Slope Water and Northern Sargasso Sea in excess of 15 per cent of their Caribbean population density. With Caribbean contamination accounted for, the relative abundances of species in Slope Water and Northern Sargasso Sea are used to assign habitat preferences. Species clusters derived from an ordination using correspondence ana1ysis agree well with the habitat preference groups. The assemblage of species in the rings occupies the middle of a gradient in faunal composition from winter conditions in Slope Water to fall conditions in the Northern Sargasso Sea. The midwater habitat is modeled as two layers, and the ring environment as a hybrid habitat consisting of a surface layer of Northern Sargasso Sea habitat and a deep layer of Slope Water habitat. This model is consistent with patterns of species abundance. It is argued that the dramatic change in the depth of the main thermocline on crossing the Gulf Stream is the major physical factor affecting fish distributions with respect to this boundary.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Woods Hole Oceanographic Institution Apri, 1976.Appendix C, Biographical notes, not included.
Suggested CitationThesis: Jahn, Andrew E., "On the midwater fish faunas of Gulf Stream rings with respect to habitat differences between slope water and northern Sargasso Sea", 1976-04, DOI:10.1575/1912/1292, https://hdl.handle.net/1912/1292
Showing items related by title, author, creator and subject.
Zooplankton biomass and related MOCNESS data for tows taken on the 1981-82 warm-core rings cruises Barber, Valerie A.; Wiebe, Peter H. (Woods Hole Oceanographic Institution, 1985-01)Compiled in this report are tables of zooplankton biomass data (displacement volume), carbon equivalents, and associated net tow data (volume filtered, depth, temperature, and salinity) collected with a Multlple ...
Craddock, James E.; Backus, Richard H.; Daher, Mary Ann (Woods Hole Oceanographic Institution, 1987-10)This data report is for midwater fishes collected during the multidisciplinary Warm-Core Rings Program in 1981 and 1982. Stations were made in and near three warm-core rings on five cruises within a period of 14 months. ...
Limits of Nematoscelis megalops in the northwestern Atlantic in relation to Gulf Stream cold core rings. I, Horizontal and vertical distributions Wiebe, Peter H.; Boyd, Steven H. (Woods Hole Oceanographic Institution, 1979-01)The hydrographic limit of the distribution of Nematoscelis megalops in the Northwestern Atlantic Ocean is usually marked by the abrupt changes in water properties across the Gulf Stream. There are, however, isolated but ...