Beginning in the 1990s mammalian predators were identified as being a major contributor to the decline of breeding shorebirds and colonial waterbirds on the barrier islands of TNC’s Virginia Coast Reserve (VCR). The two primary mammalian predators that threaten this suite of nesting birds at VCR are raccoons and red foxes.
Red foxes are not native to the VCR and raccoon populations are thought to be artificially supported and increased human populations and associated changes in land use. These species threaten the long term survival of numerous shorebirds and waterbirds, especially beach-nesting species including the federally threatened Atlantic coast Piping Plover. Because of the link between declining shorebird and waterbird populations and increasing mammalian predator populations at VCR, an avian habitat enhancement program through the use of approved mammal removal
techniques was initiated in the late 1990s. The program is now a multi-agency partnership, including federal, state, academic and NGO groups, that aims to adaptively and selectively manage mammalian predators along the Virginia barrier islands. Monitoring efforts since the program began have documented increases in the populations of certain shorebird indicator species both in terms of productivity and population size. Continual monitoring of these indicator species is critical to this project's success as it gauges where management has had the greatest impact and how the management needs to be altered year to year to account for changes in mammal populations, shorebird productivity, and nesting areas. Without monitoring, this adaptive management cycle would not be possible. The ultimate objective of this work and monitoring is to establish and maintain sufficiently high reproductive rates for local nesting shorebird and colonial waterbird species to maintain stable or increasing populations. This monitoring program has become a classic adaptive management case study: using monitoring data on bird productivity, populations, and mammal populations to develop management strategies and priorities for the upcoming year.