Satellite-monitored movements of radio-tagged bowhead whales in the Beaufort and Chukchi seas during the late-summer feeding season and fall migration

From 30 August to 6 September 1992, we tagged 12 juvenile bowhead whales (B alaena mysticetus) with Argos satellite-monitored radio tags in the Canadia n Beaufort Sea off the Mackenzie River Delta. Eight tags documented greater than or equal to 9820 km of movements between 392 locations during 111 wha le-tracking days. The whales did not move in unison. Individual movements a nd average speeds (1.1-5.8 km/h) varied widely. One whale stayed in Mackenz ie Bay for 23.5 d, while the rest stayed an average of only 2.4 d. The majo rity of locations for all whales were in shallow water: 65% at < 50 m depth and 87% at < 100 m depth. Seven whales went into water > 100 m deep and fo ur were in water > 500 m deep. The whale with the longest record traveled g reater than or equal to 3886 km to Siberia in 32.5 d, averaging 5.0 km/h. I ts westerly route through the Beaufort and Chukchi seas was between 70 degr ees and 72 degrees N and primarily in heavy ice (greater than or equal to 9 0% coverage), which was continuous west of 151 degrees W. This whale's spee d was faster, though not significantly, in heavy ice than in more open wate r. This is the first detailed documentation of the route and speed of a bow head whale during its fall migration from Canadian to Russian waters.