American Wigeon (Anas Americana) Skye Christopher G

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American Wigeon (Anas Americana) Skye Christopher G American Wigeon (Anas americana) Skye Christopher G. Haas Toronto, Ontario © Greg Schneider (Click to view a comparison of Atlas I to II) With an irreverent whistle for a voice, and Distribution a face pattern that looks as if painted by a The historical status of the American street fair artist, the American Wigeon Wigeon is difficult to ascertain. Barrows displays an air of whimsy as it languidly (1912) deemed it a rare migrant in shuffles about in shallow marshes or on Michigan, and discounted earlier agricultural fields. Primarily found in ornithological lists that included the species Michigan during migration, large numbers as a state breeder. With the benefit of an pass through the state in April and again in added century of observations during which September and October. It is only found in the wigeon has proven to be a sporadic, low the extreme southern reaches of the State in density breeder, it is possible that Barrows winter, and is one of our more uncommon simply failed to discover viable evidence. nesting dabbler species. Breeding More likely, however, is a scenario in which populations range from localized or casual the species expanded its range into Michigan populations through the Great Lakes as part of a broader eastern incursion noted eastwards into the Maritime Provinces. in the 1930s through 1950s (Peterjohn 1991, American Wigeon becomes more abundant Mowbray 1999, McGowan 2008). in the north-central U.S., and throughout much of Canada west of Ontario, as well as The first documented breeding of American encompassing much of Alaska (Mowbray Wigeon in the state came in 1938, when a 1999). More terrestrial than most ducks, nest was found in Seney National Wildlife evolutionary modifications to the bill allow Refuge, Schoolcraft County. Although a the species to graze easily on land, in a small colony persisted there for the next manner similar to geese. When foraging in decade, there have been no recent reports of water, wigeon will often associate with breeding since the inception of MBBA I. In Canvasbacks, scaup or American Coots, the 1950s through 1970s a handful of opportunistically feeding upon plant matter breeding confirmations came from brought to the surface by these and other southeastern Michigan. MBBA I herbivorous diving waterbirds (Mowbray documented evidence of nesting wigeons in 1999). a total of 34 townships, though only five confirmations were recorded. A handful of post-MBBA I breeding records originated ©2011 Kalamazoo Nature Center American Wigeon (Anas americana) Skye Christopher G. Haas from Houghton County, with nesting and the coastal marshes along the St. Mary’s documented in 1989-90, 1992-93 and 1999- River, appear to be suitable for wigeons, as 2000 (Binford 2006). they have remained present in this location for over 20 years. However, as with many The American Wigeon has experienced a other species of prairie pothole duck, it is small decline from an already low rural sewage ponds that tend to constitute population since MBBA I. Binford the preferred nesting habitat in Michigan. described three localized populations within The former breeding populace in the Michigan during MBBA I; one in the Keweenaw Peninsula seemed dependant on Keweenaw Peninsula (primarily restricted to this habitat, and most breeding the rural sewage pond system in Houghton confirmations in MBBA II were found in and Baraga Counties); eastern Chippewa sewage ponds in farm country. County in the farm country and waterways along the St. Mary’s River; and in the Lower Abundance and Population Trends Peninsula in the extensive wetlands of the Populations in North America have Saginaw Bay/Shiawassee Flats. However, oscillated in recent decades, with lows atlas workers in MBBA II did not find birds coinciding with periods of drought in the in the Keweenaw Peninsula and confirmed Prairie Provinces. Counts and estimates nesting in only three townships, all in the made in 1997 showed the overall population UP. American Wigeon sightings in MBBA to be at its highest point since 1984 II increased slightly in the NLP, and (Mowbray 1999). However, numbers began decreased in both the UP and SLP, with its to drop again in the late 1990s, and a halt to occurrence in the UP dropping from 3.44% the eastward range expansion of the mid- of all townships surveyed to 2.25%. The 20th Century has been noted (McGowan overall number of Michigan reports by 2008). Recent population estimates based on township decreased from 1.79% to 1.40%. surveys conducted by the USFWS found wigeon numbers to be at 2.4 million in 2010, Breeding Biology which was similar to both the 2009 and Nesting singly or in small, loose colonies, long-term averages of 2.6 million (USFWS American Wigeons can be found with their 2010). American Wigeons have declined in broods in open water more frequently than New York, occurring in half of the blocks other species of dabbling ducks (Mowbray they were found in during the state’s first 1999). A study conducted at Seney NWR Breeding Bird Atlas (McGowan 2008). showed that nesting wigeons utilized an 8.1 Ontario has also noted a slight decline in its ha open water marsh with only a sparse breeding wigeon abundance, with a shift of fringe of emergent vegetation around the the population center within the province to shoreline, with a wide variety of loafing and the north. One of the localized sleeping sites such as exposed mudflats, concentrations of American Wigeons in semi-submerged logs and sedge tussocks Ontario is on the Algoma side of the St. (Beard 1964). The habitat selected by Mary’s River waterways, with confirmed females for nest sites tends to be grassy breeding in Sault Ste. Marie, Manitoulin uplands or hayfields, often with low shrub Island and Sudbury (Gendron 2007); it is cover, near shallow marshes, ponds or likely that this meta-population contributes sloughs (Mowbray 1999). In Michigan, the to the longevity of the Chippewa County pastoral farmlands of eastern Chippewa breeding colonies. County, dotted with ponds and wet areas, ©2011 Kalamazoo Nature Center American Wigeon (Anas americana) Skye Christopher G. Haas Breeding wigeon in Michigan seem to have only serve to help the long-term prospects of temporal local populations. Local colonies the American Wigeon within Michigan. spring up, only to disappear after a period of time. Populations in the Keweenaw Literature Citations Peninsula and at Seney National Wildlife Barrows, W.B. 1912. Michigan Bird Life. Refuge have demonstrated this. The Special Bulletin. Michigan Agricultural breeding confirmation at the Chatham College. Lansing, MI. Sewage Ponds in Alger County was of a Beard, E.B. 1964. Duck brood behavior at female that nested and fledged young in the Seney National Wildlife Refuge. both 2004 and 2005. Journal of Wildlife Management 28: 492-521. Conservation Needs Binford, L.C. 1991. American Wigeon. In In Michigan, sewage ponds, particularly in Brewer, R., G.A. McPeek, and R.J. northern rural areas, seem to be the preferred Adams Jr. (eds.). 1991. The Atlas of location for nesting American Wigeons, Breeding Birds of Michigan. Michigan adding the species to the long list of birds State University Press. East Lansing, that benefit from this type of manmade MI. habitat. It would certainly be advantageous Binford, L.C. 2006. Birds of the Keweenaw for wigeons if conservation groups and state Peninsula, Michigan. MP 195. and federal wildlife agencies coordinated University of Michigan Museum of more closely with the local governments that Zoology. Ann Arbor, MI. operate the majority of these ponds, Gendron, M. 2007. American Wigeon. In managing them for wildlife conservation as Cadman, M.D., D.A. Sutherland, G.G. well as their intended purpose. Such Beck, D. Lepage, and A.R. Couturier initiatives have been undertaken in states (eds.). 2007. Atlas of the Breeding Birds such as Florida, Texas and Arizona, with of Ontario, 2001-2005. Bird Studies positive results for birds and for local Canada, Environment Canada, Ontario communities benefitting from the growth of Field Ornithologists, Ontario Ministry of ecotourism. Binford (2006) stated that Natural Resources, and Ontario Nature. without proper management of sewage Toronto, Ontario. ponds and their surrounding grasslands, McGowan, K.J. 2008. American Wigeon. In wigeons would not expand or even survive McGowan, K.J., and K. Corwin (eds.). within the Keweenaw Peninsula... a 2008. The Second Atlas of Breeding prophetic declaration given the species’ Birds in New York State. Cornell absence in the region during MBBA II. Of University Press, Ithaca, NY. additional benefit to the wigeon population McPeek, G.A., and R.J. Adams (eds.). 1994. in Michigan would be the adoption of low- The Birds of Michigan. Indiana impact, semi-industrialized farming University Press. Bloomington, IN. practices in eastern Chippewa County that Mowbray, T. 1999. American Wigeon (Anas promote healthy grasslands near wetland americana). In The Birds of North habitat, as opposed to the large-scale America, No. 401 (A. Poole and F. Gill, industrial monoculture farming that occurs eds.). The Birds of North America, Inc., across much of the Midwest. Finally, Philadelphia, PA. protection and restoration of the coastal Peterjohn, B.G., and D.L. Rice. 1991. The wetlands of Lake Huron and Lake Erie can Ohio Breeding Bird Atlas. Ohio ©2011 Kalamazoo Nature Center American Wigeon (Anas americana) Skye Christopher G. Haas Department of Natural Resources. Columbus, OH. U.S. Fish and Wildlife Service (USFWS). 2010. Waterfowl Population Status 2010. U.S. Department of the Interior, Washington, D.C. ©2011 Kalamazoo Nature Center .
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