Waterbirds of the Chesapeake Bay: Status, Ecological Requirements, and Threats
The Chesapeake Bay is one of the most productive aquatic ecosystems in the world and plays an important role in the life cycle of many bird species. Each year, the rich resources of the Bay attract millions of birds from throughout the western hemisphere. Dependency on the Bay varies from species that stopover for a few days during migration to species that live out their entire life cycle within a single tributary. Many species that depend on the Bay are of high international, national or regional conservation concern. For these species, the Bay is strategically important and may serve a vital role in the recovery of imperiled populations. Because many waterbirds are top consumers and collectively require a broad array of resources, they represent sensitive indicators of overall ecosystem health. Within the mid-Atlantic region, waterbirds also form the basis of a burgeoning ecotourism industry. Effective conservation of waterbirds within the Chesapeake Bay requires that we have a clear understanding of species requirements and the role that the Bay plays in their annual cycle. This document presents a brief overview of the Chesapeake Bay setting and the habitats that are believed to be significant to birds that depend on the Bay’s resources. The document then develops a conceptual model and ecological matrix that within a series of tables presents what is known about species-specific status and trends, phenology of occurrence, resource use and energetics, vital demographic rates, threats, and the importance of the Bay for waterbird species that use the Bay on an annual basis. This information is intended to provide a foundation of what is known and unknown for these species and the basis of a jumping off point for the development of a strategy to prioritize and collect critical information in the future. The Chesapeake Bay provides habitat and resources to 124 species of waterbirds throughout the year. Relationships between these species and the Bay are species-specific and complex. Although it is possible to identify some populations for which the Bay is of critical importance, information is lacking for most species such that definitive assessments cannot be made. Ongoing monitoring programs designed to evaluate population status and trends currently include a relatively small percentage of the overall community. Prominent groups lacking such programs include migratory and wintering seabirds, marshbirds, and migratory shorebirds. Marshbirds in particular stand out as a broad species group with eminent threats but for which we have little baseline data and no effective monitoring program. Information highlights the need for further assessment of monitoring programs and approaches that will result in the development of more comprehensive and coordinated efforts.