A survey of the breeding habitat of ringed seals and a study of their behavior during the spring haul-out period in southeastern Baffin Island / by T.G. Smith and M.O. Hammill. : Fs97-4/1561E-PDF

"A survey of the breeding habitat of ringed seals Phoca hispida in the fast ice was carried out between Loks Land and northern Brevoort Island on the southeastern Baffin Island coast. Maximum densities of birth lairs were found in the hummocky ice of Cyrus Field Bay and in one small bay on the south coast of Brevoort Island. Polar bear predation at birth lairs was found to be a significant mortality factor for ringed seals. Most of the seals killed were pups born between mid March and mid April. Rain and a thaw in early April melted the subnivean birth lairs, causing the pups to be exposed, and resulted in some mortality both by exposure and increased predation. Wind and low temperatures, expressed as wind chill, were significantly negatively correlated with numbers of seals hauled out on the ice in May. Peak diel densities were seen from 09:00 to 18:00. The sex ratio in the study area showed a predominance of female ringed seals. Seals orient with their heads pointed in the direction of the prevailing wind, which could be an adaptation for examining the area for polar bears. Aggressive behavior occurred between a mother and a weaned pup, and between a presumed mother seal and an adult seal lying near her pup. Seals use olfaction, sight and hearing to examine their surroundings for potential threats. They appear to become habituated to their surroundings and to various disturbances, including the sight of observers moving on the land. A hole-to-seal ratio of 6:1 (48:8) was calculated for part of the study area. However a utilized hole-to-seal ratio was calculated as 2.5:1. An independent calculation involving identified seals showed that they utilized 2.09 haul-out positions on the average. One ringed seal identified in 1978 was resighted in 1979, the first known record of site fidelity in this species"--Abstract, page iii.

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