Seasonal movements of the winter flounder, Pseudopleuronectes Americanus (Walbaum), in two contrasting inshore locations in Newfoundland

Seasonal movements of the winter flounder, Pseudopleuronectes americanus (Walbaum) 1792, were examined in a protected inlet and an exposed cove in Conception Bay, Newfoundland, from February, 1973, to March, 1974. Movements in the two locations were compared with each other and with two hypotheses o...

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Bibliographic Details
Main Author: Van Guelpen, Louis Collier.
Format: Thesis
Language:English
Published: Memorial University of Newfoundland 1974
Subjects:
Online Access:https://research.library.mun.ca/7849/
https://research.library.mun.ca/7849/1/VanGuelpen_LouisCollier.pdf
https://research.library.mun.ca/7849/3/VanGuelpen_LouisCollier.pdf
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Summary:Seasonal movements of the winter flounder, Pseudopleuronectes americanus (Walbaum) 1792, were examined in a protected inlet and an exposed cove in Conception Bay, Newfoundland, from February, 1973, to March, 1974. Movements in the two locations were compared with each other and with two hypotheses of winter flounder movement in the literature. Seasonal movements of the winter flounder from Newfoundland to Maryland are reviewed. A general scheme of seasonal movements of the winter flounder throughout its range is suggested. -- In the present study movements were inferred from changes in flounder abundance. Abundance on a given date was determined by counting fish on a fixed area of bottom using SCUBA. Environmental and physiological factors were examined in an attempt to determine the causes of movement. -- Winter flounder movements in the protected inlet and exposed cove were somewhat similar in all seasons except winter. During the winter of 1973 flounders were present in shallow water in the protected inlet until drifting pack ice entered the region. The following winter, fish were scarce in the protected inlet. This scarcity coincided with the heavy turbulence of that winter. Flounders left the shallows of the exposed cove in both winters, probably because of turbulence and perhaps drifting ice. In June many winter flounders moved into the shallows of the protected inlet and a few entered the exposed cove, where they spawned. Flounders left both regions in July or August in what may have been feeding migrations. In August or September flounders returned to the shallows of both locations. This immigration coincided with peak water temperatures and the initiation of ripening of the gonads. In the fall they left the shore zone of both sites during severe storms and returned to the shallows as the turbulence subsided.