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|Quartermaster Harbor National Audubon Society
Important Bird Area
What is an Important Bird Area?
Recognizing the need to proactively conserve remaining bird habitat in the United States, the National Audubon Society launched the Important Bird Area (IBA) program in 1995. An IBA is a specific site that is essential to one or more bird species for breeding, wintering, or migration. This program is already firmly established in Europe, where 3,600 IBA sites in 51 countries have been identified.
National Audubon in partnership with Washington Department of Fish and Wildlife began our states IBA program in 1997. In Washington, IBAs must meet at least one of the following five biological criteria:
Sites that support significant concentrations of threatened and endangered species
Sites that hold significant breeding or wintering populations of Watchlist species, which are species that show significant, long-term population declines
Sites that have an assemblage of species associated with rare or threatened habitat types
Sites that are important for long-term avian research or monitoring
Sites where birds congregate in significant numbers
Potential IBAs are nominated by Audubon chapters, natural resource agencies, and other interested parties who have gathered detailed information on bird species and their habitats. A team of ornithologists and wildlife experts then reviews the information to determine if the site qualifies for the designation. Several hundred IBAs have been identified in the United States alone, with 42 sites so far in Washington State.
Why was Quartermaster Harbor Selected as an IBA?
Tucked between the southern tip of Vashon Island and neighboring Maury Island, Quartermaster Harbors shallow protected waters, mudflats, and beaches are a haven for bird life. Every fall scores of grebes, loons, diving ducks, and sea ducks descend upon the sheltered harbor for the winter. They come because of the diverse array of food sources the harbor provides, including eelgrass, mollusks, algae, surf smelt and Pacific herring.
The harbors showcase is its intact eelgrass ecosystem, at one time a common habitat in Puget Sound. In winter the eelgrass beds become spawning grounds for Pacific herring and rearing areas for salmon and trout. The herring stock is currently the largest spawning population in southern Puget Sound and the third largest in the entire Puget Sound region. Surf smelt and sandlance also use the beaches in the harbor for spawning.
These fish and their eggs are food sources for approximately 35 bird species that frequent the harbor in the winter. Several bird species are threatened and their populations are diminishing, including the marbled murrelet, a federally threatened species, and the common loon and Brandts cormorant, both candidates on Washingtons threatened species list. In the spring its not uncommon to see thousands of Bonapartes gulls feeding on juvenile fish in the outer harbor. They are joined by Caspian terns who wander over from their breeding areas in Tacomas Commencement Bay.
The most common wintering species is the Western Grebe, whose numbers account for 8 percent of the states wintering population. This species, which has seen a precipitous decline in the last decade from habitat loss and fragmentation, was the focus of the IBA designation Approximately 1,500 grebes are counted each year in Quartermaster Harbor. The good news is that numbers here have remained stable despite declines elsewhere in Puget Sound.
Our Wintering Western Grebes (Aechmophorus occidentalis)
A common sight in the winter are the large rafts of sleeping Western Grebes in the outer harbor. With their heads turned backwards and their bills tucked under their shoulder feathers, they sleep for long stretches during the day. They feed on herring at night, propelled downward by their lobed feet where they spear and quickly swallow the fish before surfacing.
Western Grebes are unmistakable with their long, slender, swanlike neck, yellow bill, and scarlet red eyes. Before leaving Quartermaster Harbor in the early spring, one may be lucky to observe grebe courtship displays. On their breeding grounds at inland lakes and reservoirs, these displays are quite spectacular. A pair will run across the water side-by-side so rapidly that their erect bodies are completely out of the water. Nests are built in shallow, marshy areas of the lake on floating heaps of plant material. The young grebes climb onto their parents backs within minutes of hatching.
How will the IBA Designation Help Birds in Quartermaster Harbor?
By focusing attention on the most essential and vulnerable areas, the IBA program helps to promote proactive habitat conservation. Information gathered during the identification process can be used to inform land use planning and resource management agencies so that habitat needs are considered in land use decision-making. A directory of IBAs in Washington is forthcoming, which will be widely distributed to state, county, municipal planning commissions, land trusts, and other habitat conservation groups.
On the local level, IBAs can become a focal point for volunteer, citizen-science monitoring projects. In Quartermaster Harbor, monitoring can provide critical information about our western grebes and their unique habitat needs, as well as establish a baseline for other bird species at risk. The Quartermaster IBA will unite our community around common goals of stewardship and advocacy. The grebes, loons, ducks, herring, smelt and eelgrass are counting on us.
The designation of the Quartermaster Harbor IBA would not have been possible without the determined efforts of a single person: Dan Willsie. An island native and an expert birder, Dan is conversant in the tidal rhythms of the harbor and the ebb and flow of bird life. His documentation of bird sightings through the years was instrumental in developing a convincing argument for recognizing Quartermaster Harbor. Thank you, Dan.