By Michelle Fitzsimmons, Memorial University
Posted November 19, 2018
Editor’s Note: In our Research Spotlight Series we shine a light on exciting research in our province. In this post we showcase Michelle Fitzsimmons who recently defended her PhD thesis in the Cognitive and Behavioural Ecology Graduate Program, Memorial University.
My research focused on investigating the behavioural and physiological responses of Atlantic puffins to changing food resources. I studied puffins in the Witless Bay Ecological Reserve in Newfoundland and Labrador, which is home to the largest breeding colony of Atlantic puffins in North America. Over a period of four breeding seasons, I conducted two separate food supplementation studies, in which natural prey abundance also fluctuated greatly. Infra-red video cameras and Passive Integrated Transponder tags were used to identify parents and observe provisioning behaviour and parent-chick interactions.
Sex differences in parental provisioning effort were identified, revealing that female parents provisioned chicks more frequently than male parents when food resources were low. When chicks were not food supplemented, female parents had higher lipid metabolite levels than male parents, as well as parents with food supplemented chicks. This suggests that the energetic demands of chick rearing may be greater for females than males.
Chicks produced screech calls to inform parents of their hunger levels, however parents did not necessarily respond by bringing food, as they were limited by food availability. As a result, food supplemented chicks had higher mass gain than control chicks, as well as higher rates of structural growth.
These studies demonstrate the ability of parents to adjust to changing food resources while balancing self-maintenance with reproductive success. Puffins in the Witless Bay Ecological Reserve have successfully endured deteriorating foraging conditions; however, long-term shortages and mismatches in prey availability during chick rearing could potentially impact future populations, as observed in European colonies where breeding success and adult survival has declined.