Geothlypis tolmiei monticola
Status: Uncommon regular spring migrant west and west-central, rare casual east-central and east. Rare casual summer visitor northwest. Uncommon regular fall migrant west and west-central, rare casual east-central.
Documentation: Specimen: UNSM ZM9517, 29 May 1932 Cherry Co.
Taxonomy: Two subspecies are recognized (Pitocchelli 2020, Gill et al 2022): tolmiei, breeding on the Pacific slope from Alaska and Yukon south to southern California, and monticola, breeding from eastern British Columbia east to southwest Saskatchewan and south through southern Oregon and the Rocky Mountains to Coahuila and Nuevo León.
Some earlier authors separated eastern birds within monticola, including those breeding in South Dakota, as austinsmithi (Pyle 1997).
Faulkner (2010) stated that breeding birds in the Laramie Mountains and Black Hills of Wyoming are monticola, as are migrants through the state. The species is an “uncommon summer resident” in the Black Hills of South Dakota (Tallman et al 2002).
Nebraska birds are presumed monticola.
A hybrid with Mourning Warbler was reported in Kit Carson Co, Colorado; eBird cites only four overall records of this hybrid (eBird.org, accessed Jul 2023).
Spring: May 12, 12, 14 (Brown et al 2012) <<<>>> May 29, 30, 31
An earlier date is 8 May 2022 Buffalo Co.
A later date is 4 Jun 2019 Kimball Co.
Migration is from mid- to late May.
This species is a regular migrant in small numbers in the northwest (Rosche 1982). Its distribution in Nebraska may be thought of as a mirror image of that of Mourning Warbler. In the Lake Ogallala area, Keith Co, MacGillivray’s Warblers banded 14 May-4 Jun all had “obviously incomplete, rather thick white eyerings” (Brown et al 2012).
There are six documented records from the east and east central: 8 May 2022 Buffalo Co, 10 May 1994 a specimen UNSM ZM17033 “documented itself” in Lancaster Co by flying into a window (Grzybowski 1994, Brogie 1997), 12-13 May 2021 Buffalo Co, 14 May 2003 Lincoln, Lancaster Co, 15 May 1999 well-seen by two observers at Clay Center Cemetery, Clay Co, 20 May 1986 trapped, measured, and banded in Cedar Co (Brogie and Stage 1987), and an adult male captured and photographed in Cuming Co 29 May 2004 (Brogie 2005).
Additional probably correct reports are of one at Geneva Cemetery, Fillmore Co 16 May 2009, described as having “bright eye arcs”, and a Mourning-like bird with a “broken eye-ring” in Platte Co 28 May 2014.
- High counts: 4 at Oliver Reservoir, Kimball Co 17 May 1998 and 4 at Bushnell Cemetery, Kimball Co 28 May 2011.
Summer: MacGillivray’s Warbler is an uncommon breeder in the Black Hills of South Dakota (Tallman et al 2002), where it occupies riparian deciduous habitats with shrubs (Peterson 1990). Breeding also occurs in mountains of Wyoming (Faulkner 2010). In the 19th century it might have bred in northern Sioux Co where it was found in riparian thickets along streams draining northward into the Hat Creek drainage (Cary 1902). Rosche, however (1982), stated that Cary’s assumption “must be discounted” since “the nearest known breeding habitat is in the higher reaches of the Black Hills.”
The only reports suggestive of breeding since are of two birds at Gilbert-Baker Campground, Monroe Canyon, Sioux Co 25 Jul 1999, one of which may have been a young bird (Silcock 1999), and a singing bird there 14 Jun 2003 (Silcock 2003). Another was at East Ash Creek, Dawes Co 29 Jun 2022. Since habitat appears suitable in the western Pine Ridge, breeding would not be unexpected.
Fall: Aug 24, 25, 25 <<<>>> Oct 1, 2, 2
Later dates are 10 Oct 2018 Douglas Co, and 11 Oct 2015 Dundy Co.
Migration is from late Aug through early Oct.
The easternmost documented records are of an Oporornis warbler in Fillmore Co 2 Sep 2000 identified as this species (Jorgensen 2012), one at NNF Bessey, Thomas Co 7 Sep 2002, a specimen, WSC 794, collected at Albion, Boone Co 13 Sep 1982, one in northeastern Cherry Co 22 Sep 2005, and one in Douglas Co 10 Oct 2018.
There are these additional non-accepted eastern reports: a report of one at Fontenelle Forest, Sarpy Co 14 Oct 1990 was not accepted by the NOURC (Grenon 1991), and a specimen, UNSM ZM10776, taken at Roca, Lancaster Co and labeled as this species, is not now identifiable. One photographed in Dodge Co 8 Sep 2007 was not considered separable from Mourning Warbler based on the photo (Brogie 2008).
- High counts: 8 at Oliver Reservoir, Kimball Co 2 Sep 2000, 7 in Kimball and Banner Cos 31 Aug 2002, 5 at Oliver Reservoir 29 Aug 1998, and 5 there 24 Aug 2021.
Images
Abbreviations
NNF: Nebraska National Forest
NOURC: Nebraska Ornithologists’ Union Records Committee
UNSM: University of Nebraska State Museum
WSC: Wayne State College
Literature Cited
Brogie, M.A. 1997. 1996 (Eighth) Report of the NOU Records Committee. NBR 65: 115-126.
Brogie, M.A. 2005. 2004 (16th) Report of the NOU Records Committee. NBR 73: 78-84.
Brogie, M.A. 2008. 2007 (19th) Report of the NOU Records Committee. NBR 76: 111-119.
Brogie, M.A., and D.A. Stage. 1987. MacGillivray’s Warbler in Cedar County, Nebraska. NBR 55: 41-42.
Brown, M.B., S.J. Dinsmore, and C.R. Brown. 2012. Birds of Southwestern Nebraska. Conservation and Survey Division, Institute of Agriculture and Natural Resources, University of Nebraska—Lincoln, Lincoln, Nebraska, USA.
Cary, M. 1902. Some general remarks on the distribution of life in northwest Nebraska. Proceedings of Nebraska Ornithologists’ Union 3: 63-75.
Faulkner, D.W. 2010. Birds of Wyoming. Roberts and Company, Greenwood Village, Colorado, USA.
Gill, F., D. Donsker, and P. Rasmussen (Eds). 2022. IOC World Bird List (v 12.2). Doi 10.14344/IOC.ML.12.2. http://www.worldbirdnames.org/.
Grenon, A.G. 1991. 1991 (Fourth) Report of the NOU Records Committee. NBR 59: 150-155.
Grzybowski, J.A. 1994. Southern Great Plains Region. American Birds 48: 313-315.
Jorgensen, J.G. 2012. Birds of the Rainwater Basin, Nebraska. Nebraska Game and Parks Commission, Lincoln, Nebraska, USA.
Peterson, R.A. 1990. A birdwatcher’s guide to the Black Hills. PC Publishing, Vermillion, South Dakota, USA.
Pitocchelli, J. 2020. MacGillivray’s Warbler (Geothlypis tolmiei), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.macwar.01.
Pyle, P. 1997. Identification Guide to North American Birds. Part I, Columbidae to Ploceidae. Slate Creek Press, Bolinas, California, USA.
Rosche, R.C. 1982. Birds of northwestern Nebraska and southwestern South Dakota, an annotated checklist. Cottonwood Press, Crawford, Nebraska, USA.
Silcock, W.R. 1999. Summer field report, June to July 1999. NBR 67: 86-103.
Silcock, W.R. 2003. Summer field report, June – July 2003. NBR 71: 106-127.
Tallman, D.A., Swanson, D.L., and J.S. Palmer. 2002. Birds of South Dakota. Midstates/Quality Quick Print, Aberdeen, South Dakota, USA.
Recommended Citation: Silcock, W.R., and J.G. Jorgensen. 2024. MacGillivray’s Warbler (Geothlypis tolmiei). In Birds of Nebraska — Online. www.BirdsofNebraska.org
Birds of Nebraska – Online
Updated 13 Jan 2024