Grant: Research Tools and Instruments - Category 1 (<$150,000)

The upper Bay of Fundy is a critical staging area for migrating Semipalmated Sandpipers, with more than one million birds visiting the area each summer between late July and late August. When in the region, sandpipers feed extensively on invertebrates, especially the amphipod Corophium volutator, found on mudflats. In recent years, habitat use by sandpipers has changed somewhat, possibly in response to changes in the food base. This fact, coupled with an observed population decline, makes it important that we understand food habits and foraging behaviour of this species during their time in the Bay of Fundy. We have recently identified a new feeding behaviour, in which bird appear to "sip" the substrate as opposed to the more common pecking. This occurs mainly in areas where their main prey item is found at low densities, suggesting that this new method allows them to take other food. Western Sandpipers have been observed engaging in similar behaviour. We are currently conducting a study linking observed behaviour with food habits (being measured using stable isotope analysis of blood plasma). However, our behavioural observations are currently limited to daytime. This is problematic, because sandpipers are known to feed at night, and related species have been shown to use different foraging methods, habitat, and select different prey when feeding in the dark. Therefore, I propose to purchase a night vision system that will allow us to extend behavioural observations and estimates of bird density and habitat use to nighttime. This will consist of two mini-monoculars that can be attached together to form binoculars with 7x magnification for bird counts at a distance. When separate, the monoculars will be attachable to camcorders, allowing us to record behaviour for later analysis. Purchasing this system will facilitate a more complete study of sandpiper foraging ecology, which in turn will help us to fine tune habitat conservation efforts for this species. Further, results will be incorporated into ongoing studies of mudflat community ecology, and will ultimately aid in our ability to understand community structure and function.