Reproductive and Foraging Energetics of High Latitude Penguins, Albatrosses and Pinnipeds: Implications for Life History Patterns

Abstract

Pinnipeds and seabirds feed at sea, but are tied to shore to rear their young. Such a fundamental life history constraint should lead to convergent adaptations in foraging and reproductive ecology. However, intrinsic differences in mammalian and avian reproductive biology may limitthe potential for convergence. In this paper I examine both reproductive and foraging energetics of pinnipeds and seabirds. This is done in an attempt to identify traits that might be considered convergent adaptations to life in the marine environment and to show how divergent life history patterns are optimal for different reasons. From this analysis we find that seabirds invest a greater total amount of energy and protein into the offspring than pinnipeds, but this comes at the cost of making more trips to sea. Whereas pinnipeds forage in a manner more consistent with the predictions of central place foraging theory and exhibit a greater ability to compensate to the shortened breeding season typical of high latitude environments.