Distribution of ringed seals in the southeastern Beaufort Sea during late summer

The distribution and relative abundance of ringed seals (Phoca hispida) in the southeastern Beaufort Sea were examined through systematic aerial surveys in August–September of 1982 and 1984–1986. All data analyzed were collected by the same observer when sea state was ≤ 2 on the Beaufort Scale and when there was no forward glare. In late summer and early fall of 1982, 1984, and 1986, ringed seals occurred singly and in groups, to an observed maximum of 21 seals. Groups of seals were clumped into large areas of aggregation which appeared to persist for several weeks. Densities in aggregation areas ranged from 121 to 326 seals/100 km 2 , approximately 6–13 times greater than regional mean densities. The geographic extent of aggregation areas (350–2800 km 2 ) and the numbers (1 in 1984, 2 in 1982, 3 in 1986) and locations of aggregations varied among years. Ringed seals tended to aggregate most frequently and in greatest numbers in waters north of the Tuktoyaktuk Peninsula, in the general area where the Cape Bathurst polynya occurs in winter. The relative abundance of ringed seals varied among the years of the study, reaching a maximum in 1982 (42.20 seals/100 km 2 ), declining through 1984 (14.73/100 km 2 ) and 1985 (7.92/100 km 2 ), and increasing again in 1986 (19.35/100 km 2 ).