Group size and activity patterns of belugas ( Delphinapterus leucas ) and narwhals ( Monodon monoceros ) during spring migration in Lancaster Sound

• Published in: Canadian Journal of Zoology
• Main Authors: Cosens, Susan E., Dueck, Larry P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1991
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Lancaster Sound; Admiralty Inlet; Beluga*; Delphinapterus leucas; Monodon monoceros; narwhal*
• Online Access: http://dx.doi.org/10.1139/z91-227; http://www.nrcresearchpress.com/doi/pdf/10.1139/z91-227

Aerial surveys of belugas (Delphinapterus leucas) and narwhals (Monodon monoceros) were conducted in Lancaster Sound and northern Admiralty Inlet, N.W.T., during spring migration in 1987. Interspecific differences in grouping patterns and associated behaviour were observed. Group size and behaviour varied with ice type and state of breakup but patterns of variation differed between species. Behaviour of narwhals but not of belugas varied significantly with group size. Variation in group size and activity suggests that aggregation patterns are not related to predator avoidance strategies. Additional data are needed to test hypotheses about grouping patterns and behaviour in relation to prey distribution.