Dipl. Biol. Jana Jeglinski

Jana Jeglinski

Dipl. Biol. Jana Jeglinski
Lehrstuhl Verhaltensforschung
Morgenbreede 45
33615 Bielefeld Germany
Tel ++49-521-106-2192



Sea Lion Project

Ecological adaptation in Galapagos sea lions and fur seals:

foraging ontogeny and competition


I am a PhD student of the Galapagos sea lion project of the University of Bielefeld supervised by Prof. Fritz Trillmich and Prof. Dan Costa from the University of California, Santa Cruz, USA. I am interested in foraging ecology, spatial movements and trophic ecology of vertebrates, specifically pinnipeds and seabirds.


My research focuses on the foraging ecology of Galapagos sea lion (Zalophus wollebaeki) and Galapagos fur seals (Arctocephalus galapagoensis). I am investigating the ecological niches of these animals and factors that shape their foraging strategies and habitat utilization such as environmental variation and ecological interactions. I am also interested in mechanisms that shape habitat preferences and utilisation.

One of the questions that I am addressing is the ontogeny of foraging in juvenile Galapagos sea lions and the factors that influence this development as this can have major implications for juvenile survival, reproduction and population dynamics. One of these factors is the extreme variability in marine productivity that is characteristic for the Galapagos Islands; another one is the effect of a competitor (the Galapagos fur seal).

Another set of questions deals with natal habitat preferences: Galapagos sea lions surprisingly segregate in two spatially close, but genetically and morphologically distinct clusters. I am investigating if juvenile foraging habitat and their foraging ontogeny differ between these two groups, which could explain the reproductive isolation via early learning of a specific habitat and foraging strategy.


I am working in two different Galapagos sea lion colonies, one in the western and one in the central part of the archipelago. I am using stable isotope analysis and scat analysis to investigate trophic and dietary niche dimensions. I combine this information with GPS TDR (time depth recorder) data to link trophic information with diving strategies, activity patterns and habitat utilisation.

GSL juvenile with TDR fur seal with TDR


I obtained my Diploma from the University of Hamburg, where I studied the distribution of male territories in relation to habitat features in the South African fur seal (Arctocephalus pussillus pussillus) in southwestern Namibia. I then moved on to study the foraging ecology of the Giant-striped mongoose (Galidictis grandidieri) in southwestern Madagascar for a year, before starting my PhD.

go to Galápagos sea lion project main page