Acadian Flycatcher (Empidonax Virescens) Lathe Claflin

Acadian Flycatcher (Empidonax virescens) Lathe Claflin

Magee Marsh Wildlife Area, OH. 5/14/2008 © Darlene Friedman (Click to view a comparison of Atlas I to II) This widespread, summer resident of southern much more to the western and southern counties of the SLP. Here, some evidence of breeding Michigan is easily found in its deep woodland was recorded in the majority of the townships. habitat by its loud, explosive PEET-sha call. Its Elsewhere in the northern and eastern counties nest is unique: a fragile, haphazard cup which breeding evidence for the Acadian Flycatcher invariably has long tendrils of dried grasses or was much less common, being reported in zero fibrous material hanging below. It is fairly to eight townships per county. Only seven common in more mature bottomland deciduous townships in four counties in the southernmost forests or in mesic deciduous forests near portion of the NLP reported Acadian streams or shallow ponds (Whitehead and Flycatchers. Taylor 2002). In parts of its range it nests in hardwood-hemlock or white pine forests. The Twenty years later the distribution of this Acadian Flycatcher is widespread in the eastern species in Michigan has changed little. Total U.S. to the Great Plains states with its northern numbers of townships in the SLP reporting limit defined by a line running east-west breeding evidence increased marginally from through mid-Michigan and its southern limit by 35.2% to 39.6%, but it is unclear if this is the north edge of the Gulf Coast. In winter it significant. The species is still concentrated in resides on the Caribbean slopes of Nicaragua the south and west, and is almost absent in the and Costa Rica, in Panama, and in the northwest east and north to Saginaw Bay. There has been edge of South America. a modest increase (from 22 to 37 townships) in

the Washtenaw, Livingston, Oakland, and Distribution Lapeer County corridor where some large The Acadian Flycatcher was probably abundant forested landscapes exist in the Waterloo and throughout the SLP prior to deforestation in the Pinckney Recreation Areas in the western two latter half of the 19th century. Even shortly counties, and smaller woodlots with large trees after, it was a rather common inhabitant over in portions of developed areas of the eastern much of southern Michigan in wetter deciduous two. Another area of apparent expansion is the forest of five to six ha or more and not hard to NLP where the number of reporting townships find if one penetrated the deeper woods has increased from seven in four counties to 24 (Barrows 1912, Wood 1951). By the time of in 11 counties. Half of these came from Michigan’s first Atlas the species was restricted

© 2011 Kalamazoo Nature Center Acadian Flycatcher (Empidonax virescens) Lathe Claflin counties bordering the SLP and the rest were Ontario counts have been aided greatly by widely scattered. It is unknown if these reports directed efforts of The Acadian from the NLP are the result of more intensive Flycatcher/Hooded Warbler Recovery Team, so surveys, a response to climatic warming trends, their numbers are probably the most reliable. or some other factor. Conservation Needs Breeding Biology The Acadian Flycatcher is an area sensitive Acadian Flycatchers begin their nesting season forest interior species that does best in forested shortly after their arrival in mid to late May. The tracts >10,000 ha. with minimal disturbance to nest site, usually selected by the female, is the interior (Thompson et al. 1996, Fauth and typically in the fork of a small tree or shrub Cabe 2005). They are vulnerable to forest about 6-20 feet above the ground. The nest is a management practices that remove understory loose affair, often with long grassy tendrils trees (i.e. nesting sites) (Rodewald and Smith hanging below. The species is usually single 1998) and create open canopies to which brooded, but occasionally double brooding Brown-headed Cowbirds and nest predators are occurs. A breeding pair will show aggression attracted (Moorman and Guynn 2001, Heltzel against cowbirds visiting the nest site, which and Leberg 2006, Wallendorf et al. 2007). They probably accounts for the lower rate of can accept logging practices that remove single parasitism than that of other associated bird trees (Annand and Thompson 1997). They can species. Breeding site fidelity is high in both be found in smaller woodlots of 24-35 ha males and females (Whitehead and Taylor (Robbins et al. 1989) and in urban areas with 2002). forested tracts such as Oakland and Lapeer County. However it has been shown that in such Abundance and Population Trends areas nest survival, renesting after predation, (Click to view trends from the BBS) and site fidelity in subsequent years are all BBS trend data suggest that while the Acadian lower (Bakermans and Rodewald 2006, Flycatcher is doing well in the southern half of Rodewald and Shustach 2008). Hence, the U.S., it is declining at the northern limit of reproductive productivity in these fragmented its range (Sauer et al. 2008). BBS data for habitats is so low that the birds are reproducing Michigan, however, show no significant trends below replacement rates, i.e., they are ‘sink’ because the sample size is too small. This is populations. Thus, the best management perhaps not surprising because Acadian practice for this species is to identify and then Flycatchers are a forest-interior species, and maintain large forested tracts with as little BBS routes tend not to extend into forested disturbance as possible. landscapes. Data from the two Michigan atlases suggest that the abundance of Acadian Literature Citations Flycatchers appears to have increased in the last 20 years. This number has increased from 60 to Annand, E.M., and F.R. Thompson, III. 1997. 74, or 23%. Most of this increase occurred in Forest bird response to regeneration the southeast quadrant of the SLP and in the practices in central hardwood forests. Washtenaw, Livingston, Oakland, Lapeer Journal of Wildlife Management 61: 159- County corridor mentioned above. New York 171. and Ontario, which are also at the northern limit Bakermans, M. H., and A. D. Rodewald. 2006. of this flycatcher’s range and have also recently Scale-dependent habitat use of Acadian completed their second BBA, have also shown Flycatcher (Empidonax virescens) in central modest increases in the last 20 years (McGowan Ohio. Auk 123: 368-382. and Corwin 2008, Cadman et al. 2007). The

Barrows, W.B. 1912. Michigan Bird Life. population-level responses of Nearctic- Agricultural College Special Bulletin. East Neotropical migratory birds to urbanization. Lansing, Michigan, USA. Journal of Animal Ecology 77: 83-91. Bent, A. C. 1942. Life Histories of North Sauer, J.R., J.E. Hines, and J. Fallon. 2008. American Flycatchers, Larks, Swallows, and The North American Breeding Bird Survey, their Allies. U.S. National Museum Bulletin Results and Analysis 1966-2007. Version 179. 5.15.2008. U.S. Government Survey, Cadman, M.D., D.A. Sutherland, G.G. Beck, D. Patuxent Wildlife Research Center, Laurel, Lepage, and A.R. Couturier, editors. 2007. Maryland, USA. Atlas of the Breeding Birds of Ontario, Thompson, F.R., III, S.K. Robinson, D.R. 2001-2005. Bird Studies Canada, Whitehead, and J.D. Brawn. 1996. Environment Canada, Ontario Field Management of central hardwood Ornithologists, Ontario Ministry of Natural landscapes for the conservation of migratory Resources, and Ontario Nature. Toronto, birds. in F.R. Thompson, III, editor. Ontario, Canada. Management of Midwestern landscapes for Fauth, P. T., and P. R. Cabe. 2005. the conservation of Neotropical migratory Reproductive success of Acadian birds. U.S. Department of Agriculture Flycatchers in the Blue Ridge Mountains of General Technical Report NC-187, Virginia. Journal of Field Ornithology 76: Washington, D.C., USA. 150-157. Whitehead, D.R., and T. Taylor. 2002. Heltzel, J. M., and P. L. Leberg. 2006. Effects Acadian Flycatcher (Empidonax virescens) of selective logging on breeding bird Account 614 in A. Poole, and F. Gill, communities in bottomland hardwood editors. The Birds of North America. The forests in Louisiana. Journal of Wildlife Birds of North America, Inc. Philadelphia, Management 70: 1416-1424. Pennsylvania, USA. McGowan, K.J., and K. Corwin, editors. 2008. Wallendorf, J.J., P.A. Porneluzi, W.K. Gram, The Second Atlas of Breeding Birds in New R.L. Clawson, and J. Faaborg. 2007. Bird York State. Comstock Publishing response to clear cutting in Missouri Ozark Associates, Ithaca, New York, USA. forests. Journal of Wildlife Management Moorman, D.E., and D.C. Guynn, Jr. 2001. 71: 1899-1905. Effects of group-selection opening size on Wood, N.A. 1951. The Birds of Michigan. breeding bird habitat use in bottomland University of Michigan Museum of Zoology forest. Ecological Applications 11: 1680- Miscellaneous Publication 75, Ann Arbor, 1691. Michigan, USA. Robbins, C.S., J.R. Sauer, R.S. Greenberg, and S. Droege. 1989. Population declines in Suggested Citation North American birds that migrate to the Neotropics. Proceedings of the National Claflin, L. 2011. Acadian Flycatcher Academy of Sciences 86: 6758-6762. (Empidonax virescens). In A.T. Chartier, J.J. Rodewald, P.G., and K.G. Smith. 1998. Short- Baldy, and J.M. Brenneman, editors. The term effects of understory and overstory Second Michigan Breeding Bird Atlas. management on breeding birds in Arkansas Kalamazoo Nature Center. Kalamazoo, oak-hickory forests. Journal of Wildlife Michigan, USA. Accessed online at: Management 62: 1411-1417. . Urban flight: understanding individual and