Important Bird Areas

Samish/Padilla Bays


The Samish/Padilla Bay areas are located near Anacortes. The nominated area contains extensive shallow bays (Similk, Fidalgo, Padilla and Samish) as well as associated mudflats and sloughs. The portion of the Swinomish Channel where the Samish River enters into the Samish Bay is also included, along with various tidal shoreline habitat and some small islands (Samish, Saddlebag and Hat Islands). The area excludes March Point. Some of the other associated areas include diked farmlands, and grassy open fields. Padilla Bay contains a National Estuarine Reserve and the township of Bay View contains a State Park. The West 90 State Refuge lands are included as well.

The sheltered bays and sloughs of the nominated site provide critical wintering area for seabirds, ducks and geese and provide shelter and food for the large concentrations of seabirds. Padilla Bay contains some of the most extensive eelgrass beds on the west coast. These beds make the bay an ideal wintering area for Brant. The entire global population of the Western High Artic Brant (subspecies) is thought to winter in Padilla Bay. The mudflats provide wintering and migratory habitat for 20,000 shorebirds and the flatlands contain a high and diverse number of wintering raptors, including Gyrfalcon.

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Ornithological Summary

The Samish provides important winter habitat for a variety of birds. Thousands of Mallard, Northern Pintail, and American Wigeon winter along the area's coast. Many can also be found feeding in fallow fields and associated freshwater ponds. At high tide, large flocks of Dunlin and Black-bellied Plover move inland to feed and rest, returning to the muddy shorelines as the tide recedes. All of these are preyed upon by wintering hawks and falcons. Red-tailed and Rough-legged Hawks are abundant. Both adult and sub-adult Bald Eagles are dependable finds. Five species of North American falcons can be found: Gyrfalcon, Peregrine Falcon, Prairie Falcon, Merlin, and American Kestrel. Northern Harriers are also plentiful, and at the West 90 (WDFW property) they are often joined by Short-eared Owls. In eruptive years, Snowy Owls have wintered along the dikes and in the fields. On occasion, both Coopers and Sharp-shinned Hawks perch and hunt in the trees that have been planted around many of the homes and other buildings.

Padilla bay is filled with sediment from the Skagit River, so the bottom is very shallow, flat, and muddy. It is so shallow that almost the whole bay is intertidal. This means that it is flooded at high tide. When the tide goes out the whole bay empties out, exposing miles and miles of mud flats. This condition allows unusually large eelgrass meadows to grow. There are nearly 8,000 acres of eelgrass in Padilla Bay. The eelgrass and tidal flats provide an abundant food source for birds.

Conservation Issues

1) Maintaining water quality is vital to the aquatic resources of the four bays. March Point, lying between Padilla and Fidalgo Bays, harbors two large oil refineries (Texaco and Shell) that refine crude oil into gasoline, stove oil, diesel and other products for use in the Northwest and elsewhere. Their waste waters are treated but oil spils are a potential threat. At the southern end of Padilla Bay are fertilizer, seed and feed processing facilities that service the large agricultural valley. Runoff from agriculture and from increasing residential development poses a potential threat of contamination by chemicals and fecal coliform bacteria.
2) There is an increasing trend toward converting from grain and/or dairy and livestock pastures, to vegetables, perennial crops, and nursery stock. The latter do not provide suitable foraging habitat for raptors and waterfowl. Furthermore, some of the new crops require more intensive applications of fertilizers and pesticides, which may contribute to water contamination.
3) Recreational overuse may result in disturbance to birds particularly during critical wintering and migration periods. Construction of a new manufacturing plant on March Point Road may create a great deal of disturbance to nesting herons in the March Point heronry.
4) The intertidal mud flats provide ideal site conditions for the spread of Spartina, which encroaches into salt marsh and mud flat habitats, crowding out native plants and animals.
5) In this case, water diversion means diverting water into Padilla Bay. The U.S. Army Corps of Engineers has proposed diverting flood waters out of the Skagit River through an artificial channel into Padilla Bay to reduce the threat of flooding to the city of Mount Vernon. The ultimate impacts of decreasing salinity and its effects on the eelgrass beds is not known, but is the subject of a study scheduled to begin in 2002.


Padilla Bay is designated as a National Estuarine Research Reserve (