Can we Determine When Marine Endotherms Feed? A Case Study With Seabirds

ABSTRACT The foraging ecology of marine endotherms was, until recently, obscure because most species spend the greater part of their life at sea where they are difficult to observe. However, advances in solid state technology have made it possible to develop units that can be attached to animals to give information on movements (e.g. Jouventin and Weimerskirch, 1990; Wilson et al. 1991) or activity (e.g. Ponganis et al. 1991; Thompson et al. 1991) while animals are at sea. Information on the prey consumed may be obtained by stomach lavage techniques (e.g. Wilson, 1984). Assessment of stomach contents allows researchers to determine prey types but not when prey were ingested. To build up a more comprehensive picture of foraging activity of marine endotherms a unit is needed to record information on prey ingestion.