Isabella Bay, Baffin Island: An Important Historical and Present-day Concentration Area for the Endangered Bowhead Whale (<i>Balaena Mysticetus</i>) of the Eastern Canadian Arctic

Abstract

A late summer concentration of bowheads (Balaena mysticetus) at Isabella Bay, Baffin Island, was studied during 1983-88. The general results of the field study are presented and integrated with historical research and artifactual evidence of British whaling. Bowheads were observed from shore on virtually every day of adequate visibility in late summer, early fall of 1984-88, but in 1983 only two whales appeared. Peak numbers occurred in September, when as many as 68 whales were counted on one day. The whales congregated in specific areas corresponding to significant underwater topographic features. Most feeding took place in one of two deep (>200 m) troughs and most social activity occurred on a shallow bank (<30 m). Earliest arrivals were large subadults that engaged in social-sexual activities on the bank; adults arrived later and fed in deep troughs. Migrants from the north arrived in October. The mean length of 83 whales, measured photogrammetrically, was 14.4 m; 89% were >13 m long, which is about the minimum size of sexual maturity. ... Interactions of killer whales with bowheads were observed twice. About one-third of the bowheads bear killer whale scars. Whaling literature indicates that bowheads on the east coast of Baffin Island, called rocknosers, were segregated in late summer from those in the High Arctic archipelago. This population was exploited mostly after 1859 with the advent of steam power, in an operation called rocknosing. Isabella Bay was a significant port of operation during this last phase of the industry; the whalers were strategically positioned to hunt large whales in offshore troughs late in the season. Other locations with similar characteristics on the east coast of Baffin are identified from Inuit lore and historical literature.