Abstrakt: |
This article considers the dynamics in the spatial structure of breeding haulouts of spotted seals (Phoca largha Pallas, 1811) whose population inhabiting Peter the Great Bay, Sea of Japan, is currently increasing in size. Differences in age structure exist between the reproductive aggregations within the islands or groups (clusters) of islands in the Rimsky-Korsakov Archipelago. On the islands of the western and central clusters, females whelp earlier than on the eastern cluster islands, to which the breeding-population range has recently expanded. The colonization of new islands in the bay, where additional breeding sites have formed, occurs through the immigration of young females that have reached the fertile age. The stimulus to the seals' dispersal over Peter the Great Bay has been the threshold density achieved by the reproductive group at most of the traditional breeding sites, where its further increase was, thereby, restricted. [ABSTRACT FROM AUTHOR] |