About This Project

Thank you to our backers for $5600! We actually need up to $24000 - please keep donating! In the fall, most birds must pause to refuel at stopover sites where they consume fruits that are rich in antioxidants and fat. The ability of a bird to refuel may affect its ability to continue or successfully complete a migration. Our project will examine how condition (e.g. antioxidant and fat stores) on stopover may affect the behavioral decisions birds make during migration.

Ask the Scientists

What is the context of this research?

Migratory stopover sites are crucial for birds to rebuild energy stores, and the time a bird spends on a stopover can influence the timing and success of its overall migration. Additionally, during flight, birds have an elevated metabolism leading to an increase in the production of a byproduct we call reactive species. Reactive species can cause damage to cells if not balanced by an antioxidant system. During the fall, birds that normally eat insects generally turn to seasonally abundant fruit as a cheap and easy resource for dietary antioxidants and fat. I want to know whether birds that have more fat and/or antioxidants in their diet can spend less time on a stopover site, and whether they are more likely to depart in a seasonally appropriate (southerly) direction.

What is the significance of this project?

Migration is a particularly vulnerable time of year for songbirds. Birds are facing novel habitats, exhausting exercise, and are encountering more predators and human modified environments (Sillett and Holmes, 2002). Understanding how condition (how much fat and/or antioxidants a bird is able to store) influences behavior can help us to better understand their needs during this susceptible time. Further, physiological and behavioral actions during spring and fall migration can have consequences that spill over into the winter or breeding seasons (Finch et al., 2014; Legangneux et al, 2011), and how the antioxidant system responds during migration may have overarching consequences for these birds, and for other organisms that undergo periods of intense endurance exercise.

What are the goals of the project?

We will set up an automated radio tower on Block Island, Rhode Island, a stopover site for birds during migration. We will manipulate the condition of three species of birds (Blackpoll Warblers, Hermit Thrushes, and Red-Eyed Vireos) with different migration patterns.

We will use mist nets to capture these species. We will then give the birds a diet rich in fat and/or antioxidants, or a diet without extra fat and/or antioxidants. After several days in captivity, we will attach Nanotags to the birds and track them using the MOTUS network to determine whether these diets affect how long they stay and in which direction they leave Block Island.

We hope to present this research to the public and at scientific conferences, and to publish in peer-reviewed journals - we will keep you updated!