Using miniaturized light-sensing geolocators to build a migratory network for a songbird

Many migratory songbirds have declined over the last decade and understanding the causes of these declines requires information on how breeding and non-breeding populations are geographically connected. Unfortunately, for the vast majority of songbirds we have little idea of where breeding birds spend the non-breeding season. This has not only hindered our ability to effectively conserve populations but also prevented us from addressing fundamental ecological and evolutionary questions about migration. We are requesting funds for 500 miniaturized light-logging geolocators that will be used in a large-scale collaborative project aimed at determining the migration patterns of a long-distance migratory songbird, the Tree swallow (Tachycineta bicolor). The project involves 8 PIs and their research teams spread from the east to the west coast of Canada. All of the PIs currently maintain and monitor active Tree swallow breeding sites and train multiple graduate and undergraduate students at these sites each year. These 0.5g geolocators are designed to estimate daily latitude and longitude by recording the time and duration of daylight and then calibrated with an on-board clock. At each site, we will deploy 50 geolocators and then retrieve these devices the following year. In preliminary trials, we have already shown that geolocators can be successfully deployed and retrieved from Tree swallows. The application of these devices will allow us to train over 25 undergraduate and graduate students in state-of-the-art tracking technology. It will provide us with the ability to examine a number of aspects related to the ecology and conservation of migratory birds, including modeling how quickly diseases can spread between tropical and temperate areas and across the network of breeding sites, understanding how variation in climate on the non-breeding grounds influences reproductive success, and how habitat loss in parts of the network have knock-on effects in other populations.