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Vancouver Lake is a large lake just west of Vancouver, Washington, United States, north of the Columbia River and Portland, Oregon, south of Ridgefield, Washington, and the Ridgefield National Wildlife Refuge. The lake is shallow, with a maximum depth of and a mean depth of less than . There is an island in the northern half of the lake. The island was formed from the tailings of an Army Corps of Engineers dredging project, which dredged around the perimeter of the lake in the early 1980s. Lake River flows from the north shore to the Columbia River near Ridgefield. Due to seasonal variation in relative river and lake levels, Lake River experiences intermittent flow reversal and flows ''into'' Vancouver Lake for considerable periods of time. The sources for Vancouver Lake's water include a flushing channel (equipped with tidal gates to control flows) from the Columbia River near the southwest shoreline and Burnt Bridge Creek on the eastern shoreline, which winds about ten miles through many of the city's residential areas. Until the 1980s this creek was neglected and a major source of pollution for the lake. Lower River Road leads west out of Vancouver to a park on the shore of Vancouver Lake which includes a large swimming area.〔http://www.vancwa.com/lake.htm〕 A trail leads to Frenchman's Bar Park on the nearby Columbia River. ==Natural history== Vancouver Lake is home to a variety of wildlife species, many of which it shares with the nearby Ridgefield National Wildlife Refuge. Descriptions from the late 19th century describe Vancouver Lake as clear, up to twenty feet deep and containing sturgeon. Current turbidity, more shallow depths and a lack of aquatic plant structures have diminished the variety of species and more recent surveys showed the most abundant fish by mass were brown bullhead, white crappie, black crappie, and common carp, with a few juvenile salmonids and a population of channel catfish, largemouth bass, bluegill, pumpkinseed, yellow perch, naturalized goldfish, northern pikeminnow, American shad, mosquito fish, largescale sucker, and freshwater sculpin. Rich fringe environments provide habitat for amphibians such as tree frogs, reptiles such as garter snakes and a wide variety of birds, including large species such as great blue herons, osprey and bald eagles. It is within the Pacific Flyway. Large mammals on its banks include raccoons, a few black-tailed deer and an occasional coyote. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Vancouver Lake」の詳細全文を読む スポンサード リンク
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