Skip to main content
Dryad logo

Metapopulation dynamics and foraging plasticity in a highly vagile seabird, the southern rockhopper penguin

Citation

Lois, Nicolas et al. (2020), Metapopulation dynamics and foraging plasticity in a highly vagile seabird, the southern rockhopper penguin, Dryad, Dataset, https://doi.org/10.5061/dryad.vmcvdncpx

Abstract

Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connectivity and foraging niche overlap among southern rockhopper penguin colonies of the coast of southern South America using genomic and stable isotope analyses. We found two distinct genetic clusters and detected low admixture between northern and southern colonies. Stable isotope analysis indicated niche variability between colonies, with Malvinas/Falklands colonies encompassing the species entire isotopic foraging niche, while the remaining colonies had smaller, nonoverlapping niches. A recently founded colony in continental Patagonia differed in isotopic niche width and position with Malvinas/Falklands colonies, its genetically identified founder population, suggesting the exploitation of novel foraging areas and/or prey items. Additionally, dispersing individuals found dead across the Patagonian shore in an unusual mortality event were also assigned to the northern cluster, suggesting northern individuals reach southern localities, but do not breed in these colonies. Facilitated by variability in foraging strategies, and especially during unfavorable conditions, the number of dispersing individuals may increase and enhance the probability of founding new colonies. Metapopulation demographic dynamics in seabirds should account for interannual variability in dispersal behavior and pay special attention to extreme climatic events, classically related to negative effects on population trends.

Funding

Agencia Nacional de Promoción Científica y Tecnológica, Award: PICT 2014‐1870,PICT 2015‐0569

Wildlife Conservation Society

Comisión Nacional de Investigación Científica y Tecnológica, Award: ACT172065 GAB

Secretaría de Ciencia y Técnica, Universidad de Buenos Aires, Award: UBACyT 2012‐2015:20020110100107

Fondo Nacional de Desarrollo Científico, Tecnológico y de Innovación Tecnológica, Award: 1150517