|With August drawing to a close, Vashon's wintering duck species will soon be starting to arrive. American Wigeon are already a little overdue by about a week. Wigeon are dabbling ducks that feed on vegetation such as eelgrass and wild celery. They will also graze on lawns in parks and gardens. A little smaller than mallards, wigeon have medium brown bodies and gray-brown heads. The male possesses a wide green strip on the side of its head going from the eyes down the back of the neck. A light-colored patch ranges from the base of the bill to over the top of the forehead. That coloring on its forehead and crown earned it the old name of "Baldpate."
American Wigeon are common both on saltwater shorelines and small ponds throughout the island from fall through winter. There is almost always a large flock in early winter at Ellisport and smaller flocks at Lisabeula and Tahlequah. The flock at Ellisport reaches 500-600 birds in some years. The flock gathering at Christensen Cove often totals 100-200 while the group at Tahlequah is smaller at around 20-30. By mid to late winter, the large flocks disperse into smaller groups across the island's ponds and shore. Fishers Pond, the ponds along Westside Highway and Cedarhurst Road, the ponds along the road down to Lisabeula and other ponds around the island generally have wigeon in season. Bowles, the turn-of-the-twentieth century Tacoma ornithologist, writes of seeing flocks of 500,000 wigeon at the Nisqually tide flats in the late 1890's, but saw barely a fraction of that in the early 1900's. Natural fluctuations and heavy hunting caused their numbers to vacillate over the last century.
Later in the fall, any large flock of 50-100 American Wigeon may hold one or more Eurasian Wigeon. Eurasian Wigeon are Asian strays from the arctic that migrate south through Alaska rather than Siberia. They look very similar to the closely related American Wigeon and sometimes interbreed. The male Eurasian is the easiest to separate out in a wigeon flock because its head has a rufous plumage with the patch forming the baldpate on the American species appearing a buffy yellow rather than white. The Eurasian male also has pale gray sides. The females of the two species are very similar and very difficult to tell apart. Eurasians rarely show up on their own, generally they hang-out with flocks of American Wigeon. The wigeon flock in Christensen Cove just south of Lisabeula had three male Eurasian birds last year.
Eurasian Wigeon have long been recognized as regular but rare vagrants across the United States. However, West Coast sightings, reported to regional editors of American Birds, increased from fewer than 10 each year in the 1950's to over 100 per year by the mid 1980's. Even after the data has been screened for the increase of observers and like factors over that time period, a major population increase has developed. That trend has continued yet there are no theories as to the cause. Currently, two to five are seen each winter on Vashon without any known records for the past. If you have lived on Vashon for several decades and have any records of Eurasian wigeon before the 1980's, I would be interested in knowing about your sighting. Please call me at 463-7976 or email at firstname.lastname@example.org.