The Isle of May guillemot project

Higher pathogen and parasite transmission is considered a universal cost of colonial breeding due to the physical proximity of colony members. However, this has rarely been tested in natural colonies, which are structured entities, whose members interact with a subset of individuals and differ in their infection histories.

To address this, from 2011-2015, I studied a population of common guillemots, Uria aalge, infected by a tick-borne virus, Great Island virus, to explore how age-related spatial structuring can influence the infection costs borne by different members of a breeding colony. I studied a long-term study population of common guillemots on the Isle of May, Scotland. This small island is home to a population of c. 15,000 pairs of guillemots, which have been studied since the 1980s.

I developed an epidemiological model of the guillemot-tick-virus system, and parameterised this model with field observations of the movements of 63 individually recognizable, pre-breeding guillemots (the main infection risk to the colony, due to their developing immune system).

My model predictions indicated that pre-breeding guillemots have the potential to play an important role in driving virus transmission. This highlights the sensitivity of breeding colonies to changes in the behavior of their members—a subject of particular importance in the context of global environmental change.