Falco columbarius columbarius, F. c. richardsonii
Status: Uncommon regular spring and fall migrant statewide. Rare regular breeder northwest (richardsonii). Uncommon regular winter visitor statewide (richardsonii), rare Platte River Valleys and southeast (columbarius).
Documentation: Specimens: UNSM ZM12536, 20 Oct 1906 Omaha, Douglas Co (richardsonii), UNSM ZM7702, 1 Oct 1940 Stapleton, Logan Co (columbarius).
Taxonomy: Nine subspecies are recognized, six in Eurasia and three in North America: columbarius breeding Alaska and Canada, south to the northern USA but north of the range of richardsonii, suckleyi breeding Pacific Northwest, and richardsonii breeding central and south-central Canada to the north-central USA (Gill and Donsker 2017).
Columbarius and richardsonii occur regularly in Nebraska (Rapp et al 1958). Richardsonii is a northern Great Plains prairie breeder, including northwest Nebraska (Wheeler 2003); it also nests in the Black Hills of South Dakota and nearby eastern Wyoming (Faulkner 2010, Wheeler 2003). Richardsonii probably accounts for most wintering Merlins in Nebraska (Jorgensen 2012, Wheeler 2003).
Columbarius is a taiga breeder and thus a long-distance migrant passing through Nebraska mostly in central and eastern parts of the state; it is rare in Colorado (Andrews and Righter 1992) and “very rare” in Wyoming (Faulkner 2010). It winters in Nebraska, albeit “sparsely”, mostly in the Platte and North Platte River Valleys (Wheeler 2003) and in the east.
Some authors distinguish paler birds in the western part of the range of columbarius as the subspecies bendirei, noted by Rapp et al (1958) as occurring in Nebraska, but these birds are currently thought to be insufficiently different from columbarius to warrant sub-specific status (Pyle 2008).
A bird resembling the very dark, even blackish, Pacific Northwest subspecies suckleyi was reported in Banner Co 15 Jan 1998, and other very dark birds were in Saunders Co 10 Oct 2008 and near Gothenburg 1 Jan 2009. There have been several sight reports purported to be of this race in Colorado, but there are no specimens (Andrews and Righter 1992). Sibley (2000) notes “Occasional Taiga [columbarius] birds from the east apparently resemble [suckleyi]” Merlins.
Spring: winter <<<>>> May 25, 25, 25
Data from eastern Nebraska indicate a peak of occurrence in Apr, probably due to migrants of columbarius; there is no indication of such an Apr peak in the west, where columbarius is rare. Away from wintering areas in the south and east, data on spring arrival of columbarius is lacking.
Late dates above do not include reports from the Pine Ridge, where richardsonii breeds. Later reports for the species are of one in Franklin Co 2 Jun 2013, one at NNF Bessey, Thomas Co 5 Jun 2000, and one near Imperial, Chase Co 6 Jun 2003. There is a later date for columbarius of one photographed in Lancaster Co 20 May 2017; other later dates for columbarius are 2 May 2007 in the eastern Rainwater Basin and 3 May 1994 Douglas Co.
Summer: This species had been suspected of breeding on the Pine Ridge since 1938, notably Squaw Creek Canyon (Hudson 1939), but no direct evidence was obtained until 1975, when a nest with two eggs was found 13 Jun in a ponderosa pine in a sheer-walled canyon in Fort Robinson SP, Dawes Co (Lock and Craig 1975). Lock (1979) reported seeing adults in Jun 1977 northwest of Crawford, Dawes Co, and in Jun 1978 southeast of Crawford. On 9 Jun 1978 another nest was found, also at Fort Robinson SP; this nest was only 1.5 miles from the first and contained one egg and four young chicks (Lock 1979). Success of either nest was undetermined. Other nests, one with five 3-5 days-old eyases and the other with five 5-7 days-old eyases that were “too young to band”, were found 17 June 1980 in Coffee Canyon and 13 June 1980 in Cedar Canyon, respectively, in northern Sioux County (NGPC, unpublished data). Territorial birds were observed at the Coffee Canyon site in 1982, 1983 and at both sites in 1991 (NPGC, unpublished data). Nest cards were submitted for Sioux Co 1983 (Bennett 1984) and 1984 (Bennett 1985) without details. An adult female was observed on a nest, apparently incubating eggs, northwest of Crawford on 7 Jun 1984 (NGPC, unpublished data). Additional breeding season reports for Sioux Co are 15 Jun 1986, 28 Jun 1999, 12 Jul 2001, 16 Jul 1992, 17 Jul 1994, and 5 Aug 1995 and for Dawes Co 2 Jun 2008 and 3 Jun 2007.
In 1991 NGPC surveys of sites where nesting or territorial birds had been previously observed documented a total of 10 active nests, all in the Pine Ridge of Sioux and Dawes Cos. Five young were observed at one of these nests 14 Jul; another contained four young 13 Jul. There are no confirmed breeding records since 1991, however.
As with Peregrine Falcon, several northern Great Plains cities have established urban-breeding Merlins since the 1980s (Warkentin et al 2005), but so far none have been established in Nebraska.
Fall: Aug 9, 10, 11 <<<>>> winter, Sep 12,13,19 <<<>>> winter (columbarius)
Early dates above are away from the Pine Ridge and unidentified to subspecies. Earlier reports are 23 Jul 1994 Phelps Co, 3 Aug 1997 Deuel Co, two on 5 Aug 2001 Dixon Co, and one at Lake Ogallala, Keith Co “early Aug” 1993 (Brown and Brown 2001). There are earlier dates for columbarius; a molting female was found injured in Cass Co 18 Aug 2000 and was transferred to the Carolina Raptor Center where it died 3 Sep 2003 and is now a specimen (#20229) in the North Carolina State Museum (vertnet.org, accessed Sep 2017), and one was in Buffalo Co 24 Aug 2014. Most Merlin reports in the east are in Sep, probably as numbers of arriving richardsonii coincide with peak migration of columbarius. Dec dates may be of birds attempting to overwinter (see Winter).
- High counts: 4 in the eastern Rainwater Basin 26 Sep 1999, 4 in the northern Panhandle 22 Oct 2000, and 4 in Knox Co 12 Nov 2000.
A survey in eastern Nebraska (Loren and Babs Padelford, personal communication) yielded a maximum for any one year of 10 sightings.
Winter: As a species, wintering Merlins occur statewide, although numbers are lower in the east. Rosche (1982) listed it as an “uncommon winter visitant” in northwest Nebraska and single birds are commonly reported on CBCs statewide. The winter range underwent a northward expansion on the Great Plains 1960-1990 (Warkentin et al 2005); Nebraska reports suggest this increase is largely due to increasing numbers of wintering columbarius.
Most wintering birds are richardsonii (Wheeler 2003), which are more common westward, and common in eastern Colorado (Wheeler 2003).
Regarding wintering of columbarius, Wheeler (2003) stated “Very sparse wintering in the interior states”; Wheeler’s maps showed wintering along the Platte and South Platte River Valleys in Nebraska, but not in eastern Nebraska. However, recent reports of columbarius indicate wintering in eastern Nebraska as well: 1 Jan 2015 Knox Co, 4 Jan 2016 Douglas Co, 8 Jan 2010 male Dawson Co, 22 Jan 2017 Douglas Co, 31 Jan 2016 Lincoln Co, 6 Feb 2015 Douglas Co, 7 Feb 2016 Kearney Co, 9 Feb 2015 Douglas Co, 16 Feb 2002 Douglas Co, 18 Feb 1994 Washington Co, and 18 Feb 2014 Douglas Co
- High counts: 4 in the Panhandle 24 Jan 1999 and 4 on the Norfolk CBC 17 Dec 2005.
CBC: Christmas Bird Count
NGPC: Nebraska Game and Parks Commission
NNF: Nebraska National Forest
SP: State Park
UNSM: University of Nebraska State Museum
Andrews, R., and R. Righter. 1992. Colorado birds. Denver Museum of Natural History, Denver, Colorado, USA.
Bennett, E.V. 1984. 1983 Nebraska nesting survey. NBR 52: 47-50.
Bennett, E.V. 1985. 1984 Nebraska nesting survey. NBR 53: 46-49.
Brown, C.R., and M.B. Brown. 2001. Birds of the Cedar Point Biological Station. Occasional Papers of the Cedar Point Biological Station, No. 1. Nebraska, USA.
Faulkner, D.W. 2010. Birds of Wyoming. Roberts and Company, Greenwood Village, Colorado, USA.
Gill, F., and D. Donsker (Eds). 2017. IOC World Bird List (v 7.3), accessed 30 January 2018.
Hudson, G.E. 1939. Some ornithological results of a six-week’s collecting trip along the boundaries of Nebraska. NBR 7: 4-7.
Jorgensen, J.G. 2012. Birds of the Rainwater Basin, Nebraska. Nebraska Game and Parks Commission, Lincoln, Nebraska, USA.
Lock, R.A. 1979. A second nesting record for Merlins in Nebraska. NBR 47: 39.
Lock, R.A., and R. Craig. 1975. Merlin nest in Nebraska. NBR 43: 78-79.
Pyle, P. 2008. Identification Guide to North American Birds. Part II, Anatidae to Alcidae. Slate Creek Press, Bolinas, California, USA.
Rapp, W.F. Jr., J.L.C. Rapp, H.E. Baumgarten, and R.A. Moser. 1958. Revised checklist of Nebraska birds. Occasional Papers 5, Nebraska Ornithologists’ Union, Crete, Nebraska, USA.
Rosche, R.C. 1982. Birds of northwestern Nebraska and southwestern South Dakota, an annotated checklist. Cottonwood Press, Crawford, Nebraska, USA.
Sibley, D. A. 2000. The Sibley guide to birds. Alfred A. Knopf, New York, New York, USA.
Warkentin, I.G., N.S. Sodhi, R.H.M. Espie, A.F. Poole, L.W. Oliphant, and P.C. James. 2005. Merlin (Falco columbarius), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, New York, USA. https://doi.org/10.2173/bna.44.
Wheeler, B.K. 2003. Raptors of Western North America. Princeton University Press, New Jersey, USA.
Silcock, W.R., and J.G. Jorgensen. 2017. Merlin (Falco columbarius), Version 1.0. In Birds of Nebraska — Online. www.BirdsofNebraska.org