Nutrition of the Baikal seal and its role in the trophic structure of the Baikal ecosystem

Abstract

The purpose of the work was to give as complete an overview as possible of the currently available publications related to the nutrition of the Baikal seal (Pusa sibirica).More than 50 sources devoted to the stated topic served as materials for writing the review.The results of the analysis of published sources showed that the Baikal seal feeds mainly on 4–6 species of small pelagic fish throughout the year, and the main food is two species of golomyankas of the Comephoridae family. The hypothesis according to which the well-being of the species is largely determined by the use of the pelagic crustacean Macrochectopus branickii for food does not stand up to criticism and is unlikely to reflect the real picture. The distribution of the Baikal omul is such that it does not exclude, but does not in any way contribute to the fact that the seal consumes it in significant quantities. However, the consumption of salmonids as food has become more frequent in recent years (the reasons for this cannot be established), but even now these fish constitute <3% of the biomass of fish consumed by the entire population of the Baikal seal per year. All adaptive morphophysiological, anatomical and behavioral features of the species clearly indicate that the seal has developed a food strategy aimed at the effective production and utilization of the above-mentioned fish species.Conclusion: the basis of the diet of the Baikal seal is made up of small non-commercial pelagic fish species, therefore, even with a large population, seals cannot be the reason for the reduction in commercial omul stocks.The practical significance of the work lies in the fact that its conclusions must be taken into account when developing rules and strategies for exploiting the Baikal seal population.