. The Canadian field-naturalist. Natural history. 386 The Canadian Field-Naturalist Vol. Ill. Figure 4. Satellite image of ice conditions during reconnaisance surveys in northern Foxe Basin, including Fury and Hecla Strait in June, 1994. where they were consistently found throughout the summer, associated with loose pack ice. Both fluke- up diving and skim feeding (see Wursig et al. 1989) were observed in this area. Other behaviours such as tail-slapping, rolling and, apparently, sleeping were also observed. Two calves were seen from the boat and two were also seen from the aircraft. It is not
. The Canadian field-naturalist. Natural history. 386 The Canadian Field-Naturalist Vol. Ill. Figure 4. Satellite image of ice conditions during reconnaisance surveys in northern Foxe Basin, including Fury and Hecla Strait in June, 1994. where they were consistently found throughout the summer, associated with loose pack ice. Both fluke- up diving and skim feeding (see Wursig et al. 1989) were observed in this area. Other behaviours such as tail-slapping, rolling and, apparently, sleeping were also observed. Two calves were seen from the boat and two were also seen from the aircraft. It is not known whether these were the same or different calves. Based on observations from reconnaissance sur- veys, the area between 82°15' and 80°35'W was selected for systematic surveys. From these surveys, we estimated 256 ± Bowheads in the survey block on 11 August and 284 ± Bowheads on 15 August (Figure 5), based on sightings of 47 and 53 individuals respectively (Table 1). The distribution of whales was somewhat more clumped on 15 August, thus the Standard Error is wider than the one calculated for the survey on 11 August. Underestimation of strip width would result in an overestimation of Bowhead numbers. Harwood and Borstad (1985), flying at an altitude of 305 m, used a 2 km wide strip for Bowhead whale surveys in the southeast Beaufort Sea. Their distribution of sighting distances indicated that Bowheads were visible up to a distance of 1100 m. If a strip width of 2 km were to be assumed in the present study, estimates of surface Bowheads would reduce to 154 ± (11 August) and 170 ± (15 August). The surveys conducted in 1994 were intended to provide a minimum estimate of visible Bowhead present in Foxe Basin. Future surveys would bene- fit from using line transect methods where sighta- bility as a function of distance from the aircraft, group size and behaviour can be quantified and appropriate correction factors applied to the final estimate (Cooke 19
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