Breeding evidence |
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Long-term BBS trends
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Characteristics and Range This dark-plumaged, large dabbler has long been a favourite with hunters across its core range, which spans much of eastern North America, east of the Prairies and the Mississippi River. As a consequence, its population is one of the best-studied and most intensively managed of all the wildfowl. At one time it was the most abundant duck in eastern North America (Longcore et al. 2000). It is rare and very local in western North America, restricted to isolated populations on the Prairies and in the far west.
Distribution, Abundance, and Habitat Very small numbers were introduced to south-western British Columbia and Washington during the 1960s and 1970s (Campbell et al. 1990 ). The only Atlas records came from the lower Nanaimo River valley on Vancouver Island, where several pairs that included pure American Black Ducks were observed in 2011. Continued breeding was confirmed by the presence of fledged young in the company of an adult female on July 31st. These birds represent the remnants of a long-established population released in this area in the late 1970s ( Campbell et al. 1990 ).
The population in British Columbia very likely numbers fewer than 50 birds. The number of seemingly pure American Black Duck appears to have dropped dramatically since 2006, as a result of genetic swamping through hybridisation with Mallards. The lack of Atlas period records from the rest of the province suggests that the other introduced populations, and previously known escapees from aviculturalists in the Fraser Valley, have almost or entirely died out.
During the breeding season in the Nanaimo River valley area, it frequents freshwater lakes and ponds, sloughs and marshes within an agricultural and wooded landscape.
Conservation and Recommendations Management of the species is largely confined to its population centre in eastern North America, where it is the focus of the only single species Joint Venture conservation program on the continent (the American Black Duck Joint Venture). There are no current conservation efforts for the species in British Columbia, and its alien status here means conservation of the few remaining introduced birds in British Columbia is not a priority.
Recommended citation: Davidson, P.J.A. 2015. American Black Duck in Davidson, P.J.A., R.J. Cannings, A.R. Couturier, D. Lepage, and C.M. Di Corrado (eds.). The Atlas of the Breeding Birds of British Columbia, 2008-2012. Bird Studies Canada. Delta, B.C. http://www.birdatlas.bc.ca/accounts/speciesaccount.jsp?sp=ABDU&lang=en [17 Sep 2024]
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