The biology of Gammarus (Crustacea, Amphipoda) in the northwestern Atlantic. IV. Gammarus lawrencianus Bousfield

Gammarus lawrencianus is an endemic estuarine species of the northwestern Atlantic, found from Labrador south to the Gulf of Maine. Fifty percent maturity for the females occurs at 5.25 mm at Holyrood, Newfoundland, and at 4.4 mm at St. Andrews, N.B. In Newfoundland, females produce a series of broo...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Steele, D. H., Steele, V. J.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1970
Subjects:
Online Access:http://dx.doi.org/10.1139/z70-215
http://www.nrcresearchpress.com/doi/pdf/10.1139/z70-215
Description
Summary:Gammarus lawrencianus is an endemic estuarine species of the northwestern Atlantic, found from Labrador south to the Gulf of Maine. Fifty percent maturity for the females occurs at 5.25 mm at Holyrood, Newfoundland, and at 4.4 mm at St. Andrews, N.B. In Newfoundland, females produce a series of broods between March and October, at which time they enter the resting stage. The oogonia begin to enlarge in January but are not released into the brood pouch until March. The young hatched in the spring mature during the summer and may produce several broods before October. The older generation disappears in the summer. The population rises quickly to a peak in August or September in the river water but declines rapidly in early winter. Only in the bottom of pools and in the barrachois pond do specimens apparently survive until spring.