Ecology of the circulation of infectious agents in colonial vertebrate populations: surveillance, understanding and implications for biodiversity conservation in sub-Antarctic islands – ECOPATHS

Describing and understanding factors affecting the distribution and transmission of pathogenic agents in wild animal populations is important for basic and applied reasons, notably in the current context of global change and recurrent emergences of infectious diseases, which can be related to human activities. Various tools can be used to track, understand and respond to the emergence of infectious agents. Here, we propose to integrate biomedical and molecular epidemiology approaches with population ecology and anthropological approaches to address those issues. Building on our experience in these fields and on the unique situation of sub-Antarctic islands (Crozet, Kerguelen and Amsterdam), where dense but threatened populations of colonial marine vertebrates (albatrosses, penguins, seals) breed in highly structured but relatively simple communities that can be affected by infectious diseases, we propose to address critical hypotheses on the processes underlying eco-epidemiological dynamics and their impacts.

A first axis of the work will focus on documenting how infectious agents are shared at a hierarchy of spatial scales among vertebrates host populations in the native vertebrate and introduced species communities of southern ocean islands. We will notably explore the potential usefulness of scavanger and predatory species, such as skuas and giant petrels, as epidemiological senitnelles, and their potential roles as spreaders of pathogenic agents. A second axis will focus on the particular situation of Amsterdam Island, where recurrent epizooties of avian cholera are responsible for massive die-offs of nestlings of albatrosses and penguins, and where the test of the use of a vaccine approach is possibly humpered by the negative effects of introducted species like rats. That part of the project will uniquely benefit from the independantly funded plan of eradiction of introduced species from that island, to be implemented in 2022, and a collaboration with the stakeholder in charge of that eradication plan, the National Nature Reserve of the Terres Australes. A third axis will explore how modelling and social science approaches could be used to better apprehend the risks of emergence of infectious disease in such systems and ways to manage them.

The project benefits from involing a consoritium of partners and collaborators with a broad range of complementary skills. It will also draw upon the use of samples and access to field set ups provided by a multi-year field research program supported by the French Polar Institute. The results are expected to have broad basic and applied implications.