Modified Leslie–DeLury Population Models of the Long-Finned Pilot Whale ( Globicephala melaena ) and Annual Production of the Short-Finned Squid ( Illex illecebrosus ) Based upon their Interaction at Newfoundland

Distributions and seasonal movements of Globicephala melaena and Illex illecebrosus evince similar patterns and the cetacean feeds almost exclusively on the cephalopod while inshore at Newfoundland. Peaks in Newfoundland landings of both species are coincident and this is taken to indicate that avai...

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Bibliographic Details
Published in:Journal of the Fisheries Research Board of Canada
Main Author: Mercer, M. C.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1975
Subjects:
Online Access:http://dx.doi.org/10.1139/f75-135
http://www.nrcresearchpress.com/doi/pdf/10.1139/f75-135
Description
Summary:Distributions and seasonal movements of Globicephala melaena and Illex illecebrosus evince similar patterns and the cetacean feeds almost exclusively on the cephalopod while inshore at Newfoundland. Peaks in Newfoundland landings of both species are coincident and this is taken to indicate that availability of pilot whales inshore depends on that of short-finned squid. Progressively higher peaks in squid landings with progressively lower peaks in whale landings are interpreted to indicate depletion of the whale populations. Utilizing squid landings as a correction for availability of whales, closed system models are generated to estimate the initial population size of the exploited pilot whales at less than 60,000. Estimates of potential squid consumption by these stocks indicate that annual squid production may be in the order of several hundred thousand tons.