The Northwest Atlantic population of the Roseate Tern was listed as Endangered in 1987 under state and federal endangered species acts, and despite intensive efforts to protect birds at nesting colonies, has failed to meet recovery goals. Demographic analyses show that low recruitment of breeding birds is contributing to the population’s failure to thrive. Therefore, terns are experiencing difficulty during the period between fledging and reaching sexual maturity at 3 years. The most vulnerable time in this period is during the time fledglings are preparing for their first migration to South America—the time they are staging with a care giving adult at locations in the region with abundant, suitable prey (typically sand lance). Very little is known about foraging of staging terns. In addition, there is no understanding of how a major shift in the marine community at critical staging sites on Cape Cod and Nantucket with the exponential growth of another sand lance specialist—Gray Seal—may be impacting tern foraging. We propose to investigate 1) the foraging ecology of staging Roseate Terns by documenting foraging locations, identifying prey species delivered to terns in roosting flocks, and quantifying prey size and delivery rate to staging terns; and 2) the impact of seals on staging terns through a meta-analysis of existing information including diet overlap, and spatial displacement. Our request to the Blake-Nuttall Fund is for support of personnel costs related to data collection and analysis.
Program Report: Tern Vulnerability at Staging Grounds Understanding Prey Availability