. The Canadian field-naturalist. Natural history. 2002 Lucas and McAlpine: Ringed Seals on Sable Island 609. Figure L Juvenile female Ringed Seal, shark-killed, Sable Island, Nova Scotia. 5 January 1998 ( photo). northwest Foxe Basin during March to September. The shark-killed Ringed Seal was in better condition than the seals that died on the beach. Lucas and Daoust (2002) found that the dorsal and sternal regions of the blubber in intact carcasses of Harp and Hooded seals found on the beach were significantly thinner than in shark-killed animals. This indicates that while Harp and Hoo
. The Canadian field-naturalist. Natural history. 2002 Lucas and McAlpine: Ringed Seals on Sable Island 609. Figure L Juvenile female Ringed Seal, shark-killed, Sable Island, Nova Scotia. 5 January 1998 ( photo). northwest Foxe Basin during March to September. The shark-killed Ringed Seal was in better condition than the seals that died on the beach. Lucas and Daoust (2002) found that the dorsal and sternal regions of the blubber in intact carcasses of Harp and Hooded seals found on the beach were significantly thinner than in shark-killed animals. This indicates that while Harp and Hooded seals which come ashore are likely to be those animals in poor condi- tion (McAlpine and Walker 1990), those that are killed by sharks may represent seals which are healthier and feeding at sea, and less likely to haul out. Thus, the greater blubber thickness and the pres- ence of fish otoliths in the gut of the shark-killed Ringed Seal suggests that healthy individuals of this species may be found in waters of the Scotian Shelf. While the dramatic increase in numbers of Harp and Hooded seals on Sable Island is well-document- ed (Lucas and Daoust 2002), the apparent increase in sightings of Ringed Seals may, in part, be the result of beach surveys for Harp and Hooded Seals carried out from 1995 to 1998. Eight of 14 Ringed Seals were found during these surveys, which were discon- tinued after spring 1998. Prior to these systematic surveys for Harp and Hooded seals. Ringed Seals may have been overlooked among the large numbers of juvenile Grey {Halichoerus gi-yjms) and Harbour (Phoca vitulina) seals hauled out on Sable Island (Boulva and McLaren 1979; Mansfield and Beck 1977; Stobo and Zwanenburg 1990). Although Fisheries and Oceans Canada have car- ried out research on seals on Sable Island during January-February and May-June of most years since 1965, the focus of these studies has been Grey and Harbour seals. If Ringed Seals were observed, these sightings were not recorded
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