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The myctophid species Benthosema glaciale and Ceratoscopelus maderensis were predominant in the catches of 10 mesopelagic fish surveys conducted in the Slope Sea, south and southeast of Nova Scotia. The area surveyed included both cold northeastern (Labrador Slope Water - LSW) and warm southwestern (Warm Slope Water - WSW) components of this water mass. The sub-polar-temperate species, B. glaciale, was found to be only about 15% as abundant in WSW as in LSW. Nonetheless, it occurred throughout WSW and reproduced there, maturing at a younger age than in LSW. The temperate species, C. maderensis, the predominant myctophid caught in WSW, had a life cycle of one yr. in most cases, but a small proportion lived for a second year and these occurred primarily in LSW. These larger animals matured sexually and contributed to spawning in the LSW/WSW boundary area, but their reproductive contribution elsewhere in LSW and in continental slope waters remains to be established. Both species had diverse diets, the taxonomic compositions of which overlapped substantially. [ABSTRACT FROM AUTHOR]

Fishing trials with bottom fixed gears (primarily gillnets but also shrimp and crab traps and longlines) were conducted on the continental slope off Nova Scotia in August 1991. Fishing was conducted at several depths between 500 and 2800 m in two areas, one on the open slope south of Emerald Bank and the other at the mouth of The Gully, a large canyon. Catches by gillnets accounted for about 90% of the total and were predominated by deepwater chimaera (Hydrolagus affinis), black dogfish (Centroscyllium fabricii) and Portuguese shark (Centroscymnus coelolepis). The most frequently caught species in traps were snubnose eel (Simenchelys parasitica) and abyssal grenadier (Coryphaenoides armatus). Variations in catches by depth and area are described, and comparisons are made with catches from otter trawl surveys at similar depths with regard to the most prominent species caught and their size compositions. [ABSTRACT FROM AUTHOR]