The role of multi-colony studies in understanding seabird demography

• Main Authors: 3rd World Seabird Conference 2021, Sauser, Christophe
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Underline Science Inc. 2021
• Subjects: Climate Change; Ecosystem; Ecology; FOS Biological sciences; Animal Science; Genomics; Brown Skua; Snow Petrel; Snow Petrels
• Online Access: https://dx.doi.org/10.48448/w48z-pk31; https://underline.io/lecture/34892-the-role-of-multi-colony-studies-in-understanding-seabird-demography

Abstract: Breeding at the right place is essential for seabirds to ensure a compromise between access to the resources, being safe from predation and deal with local weather. A challenge in ecology is to predict the demographic responses of populations in a context of climate change. Understanding demographic differences between multiple populations or colonies is central to determining some of the underlying mechanisms that drive these responses. Variability in population responses occur at large spatial scales, and studies have already shown different demographic strategies between several sites, but this understanding remains fragmentary and insufficient. However, on small spatial scales, analyzes between several nearby colonies have rarely been conducted, neglecting direct weather effects of other local effects. Here, we estimated the demographic parameters between several seabird colonies at different spatial scales and then assessed the differences in the demographic responses of these populations to environmental variations. We used individual monitoring data from three nearby colonies of snow petrel to investigate small-scale differences. To investigate the large-scale differences, we used two distant populations of closely related marine predators with similar ecological requirements, the south polar skua and the brown skua. Using capture-mark-recapture models, we estimated the survival and reproductive performance of each species at different sites. Our results show that breeding performance can vary both on large and small spatial scales. In addition, for snow petrels, local weather conditions may affect colonies differently resulting in different demographic responses. Very few studies have taken into account spatial heterogeneity when studying seabird population responses and generally make inferences from a single study site. To draw general conclusions about these responses, it is necessary to study in more detail, on several sites, a greater number of species in marine ecosystems. Authors: Christophe Sauser¹, Nathan Pacoureau², Karine Delord¹, Christophe Barbraud¹ ¹CNRS - Centre d'étude biologique de Chizé, ²Simon Fraser University