Pelagic Amphipoda of the Belle Isle Strait Region

The distribution of certain pelagic Amphipoda taken in the Belle Isle strait region during the summer of 1923 is correlated with ocean currents, light intensity and size of individuals. Hyperoche medusarum, Themisto libellula and Pseudalibrotus glacialis are index species of the cold Labrador curren...

Full description

Bibliographic Details
Published in:Journal of the Fisheries Research Board of Canada
Main Author: Bousfield, E. L.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1951
Subjects:
Online Access:http://dx.doi.org/10.1139/f50-009
http://www.nrcresearchpress.com/doi/pdf/10.1139/f50-009
Description
Summary:The distribution of certain pelagic Amphipoda taken in the Belle Isle strait region during the summer of 1923 is correlated with ocean currents, light intensity and size of individuals. Hyperoche medusarum, Themisto libellula and Pseudalibrotus glacialis are index species of the cold Labrador current in the area. Hyperia galba and H. medusarum are presumably also cold water indicators. Themisto abyssorum in sizeable numbers, and Calliopius laeviusculus are related to waters of the gulf of St. Lawrence. Themisto libellula, T. compressa form compressa and T. compressa form bispinosa are more numerous, while T. abyssorum is less numerous at the surface during daylight than during darkness. Part of the breeding season of T. compressa and T. abyssorum occurs in the area during August and September, when the young of both species are much more numerous than the adults, particularly at the surface. A new southern limit of distribution for P. glacialis is established. The known distribution of the tropical genus Phronima is extended into the gulf of St. Lawrence.