Antigone canadensis canadensis, A. c. tabida
Status: Abundant regular spring and fall migrant central, common west, uncommon east. Rare regular breeder Panhandle and north-central, rare casual breeder Rainwater Basin. Rare casual summer visitor statewide. Rare casual winter visitor central Platte River Valley.
Documentation: Specimen: UNSM ZM7836, 19 Mar 1959 Overton, Dawson Co.
Taxonomy: This species was moved recently from genus Grus to genus Antigone (Krajewski et al 2010).
Recent authors (Clements et al 2016, Gill and Donsker 2017) recognize five subspecies, following Rhymer et al (2001) who found that rowani and tabida were genetically indistinguishable, and were part of a clade including sedentary United States subspecies pratensis of Georgia and Florida, and pulla of Mississippi; Cuban nesiotes was not included in the study. Long-distance migrant subspecies canadensis belonged to a clade genetically distinct from the other subspecies in the study.
The epithet tabida has precedence over rowani; thus, Nebraska birds are canadensis and tabida.
In a recent publication (Central Flyway Webless Migratory Game Bird Technical Committee 2018, “CFMC”) regarding the Mid-Continent Population (MCP) of Sandhill Cranes, satellite telemetry studies are cited that suggest four MCP “breeding affiliations” i.e. non-contiguous breeding sub-populations: Western Alaska-Siberia, northern Canada-Nunavut, West-central Canada-Alaska, and East-central Canada/Minnesota (Krapu et al 2011, 2014). Based on mitochondrial DNA studies (Krapu 2011, 2014), the first two affiliations are >92% subspecies canadensis, and the last two >85% tabida (CFMC Table A1). The ranges of these breeding affiliations are shown in MCP Figure 2 (page 8); all four affiliations stage on the Platte River in spring.
Lingle (1994) considered about 80% of the Sandhill Cranes which migrate through Nebraska to be canadensis (Lesser Sandhill Crane), and 20% rowani plus tabida (Greater sandhill Crane). Recent genetic sampling of the population in the central Platte River Valley suggests, however, that Greater Sandhill Cranes (tabida plus rowani) comprise about 42% of the total (Krapu et al 2014).
A large number of Sandhill Cranes killed in a severe hailstorm in Hall Co 24 Mar 1996 were expertly prepared by Thomas Labedz at UNSM; exposed culmen measurements of single females at the large and small extremes clearly assigned them to tabida (culmen 127, tarsus 220, ZM17404) and canadensis (culmen 89, tarsus 162, ZM17423) respectively, based on measurements in Pyle (2008). There were numerous intermediate birds; presumably these comprised the lower end of the mensural range of tabida (sensu Rhymer et al 2001, Pyle 2008).
Changes Since 2000: Sandhill Crane has bred sporadically in the Rainwater Basin since the mid-1990s and more consistently in the north and west since the early 2000s.
Estimates of the number of Sandhill Cranes stopping-over in the Central Platte River Valley are variable from year to year, but estimates have generally been around 500,000 birds (Dubovsky 2018). Numbers have increased since about 2007 with a notable spike of 1,005,612 birds estimated to be present in the Central Platte River Valley during spring 2018 (Dubovsky 2018), followed by a similar total of 946,000 in spring 2019 (Liddick 2019).
Sandhill Crane staging patterns in the central and upper Platte River regions have changed in response to changes in riverine roosting habitat and also changes in land use (Krapu et al. 2014, see Comments). In addition, increasing numbers have been observed in Lincoln, Keith and Garden Counties in recent years and others have noted concentrations pushing east of the traditional staging areas in the Big Bend reach of the Platte River.
Sandhill Crane migration is apparently also shifting temporally based on weekly aerial surveys conducted by the Crane Trust (cranetrust.org), as birds are arriving and numbers are peaking earlier in spring than has been traditionally observed, likely in response to changes in climate. Surveys conducted during the last week in Feb by the Crane Trust (cranetrust.org) during the early part of migration show large increase in numbers in the area between Chapman, Merrick Co and Overton, Dawson Co; for 2017 and 2016, 194,825 (+/- 7.3%) and 213,650 (+/-5.1%) were counted respectively, whereas the highest previous tally reported for these surveys was in 2009, when 62,900 were present.
Spring: Jan 23, 24, 24 <<<>>> May 24, 24, 25
The first arrivals often appear in late Jan, although these birds may retreat southward during periods of inclement winter weather. There are earlier reports 14-28 Jan 2011 near Scottsbluff, Scotts Bluff Co and 16 Jan 2000 and 18 Jan 1999 in the central Platte River Valley; 200 were in Lincoln Co 15 Jan 2009 and 90 in Kearney Co by 15 Jan 1995. There are later reports 29 May 2001 in Otoe Co, 29 May 2016 at Rowe Sanctuary, Buffalo Co, and 7 Jun 2019 Hall Co (Malzahn et al 2018). “Spring stragglers have been seen as late as early June” in the Keith Co area (Brown and Brown 2001). Most depart by the end of Apr.
Peak numbers occur 20 Mar-5 Apr, when large numbers occur between Grand Island and Kearney (Lingle 1994). A notable peak count was the 598,000 between Overton, Dawson Co and Chapman, Merrick Co in the central Platte River Valley 24 Mar 2018 (Caven 2018). There are at least two possibly discrete groups apart from those in the central Platte River Valley: about 25,000 occupy an area east of Hershey in Lincoln Co where counts have been in the 10,000-25,000 range since at least 2005 (Silcock 2005, 2013) and 40,000-50,000 used meadows in the Clear Creek WMA, Garden Co in 2005 (Silcock 2005). Numbers are increasing in Scotts Bluff Co, where up to 7500 were present 7 Apr 2018.
Since the 1990s, when modern breeding began, sightings into May in suitable habitat are likely non-breeding sub-adults. A photo of eight birds in Lincoln Co 8-9 May 2015 showed four birds resembling adults and four young birds; yearlings of tabida may remain in pre-breeding flocks during their second summer (Gerber et al 2014), thus the older birds in the flock were likely non-breeding sub-adults (see Summer).
In spring, this species has become regular in the east; flocks generally consist of fewer than 100 birds, although “hundreds” flew over Creighton, Knox Co 23 Mar 2015 and 1500 were at Deep Well WMA, Hamilton Co 14 Mar 2018
Birds trapped and outfitted with satellite transmitters (n=153) along the Platte River 1998-2003 during spring subsequently migrated to points that collectively covered a large geographic area encompassing eastern Hudson Bay west across Canada extending to portions of eastern Siberia (Krapu et al 2011).
Summer: Sandhill Cranes nested in most of Nebraska until about the beginning of the 20th century (Bruner et al (1904). Unregulated hunting, coupled with habitat loss, contributed to the species’ extirpation as a breeder.
Iowa’s first breeding record in about 100 years was in 1992 (Kent and Dinsmore 1996), and, beginning in the mid-1990s, sightings of juveniles with adults in Nebraska began to accumulate in the Rainwater Basin (Jorgensen 2002, 2012). Breeding was first confirmed when a pair with two downy colts was found at Harvard WPA, Clay Co 29 May 1999, and a pair with a single juvenile was found in early Jun the same year at Kissinger Basin WMA, Clay Co (Hoffman 1999). Evidence suggests breeding had probably occurred previously; in 1994, two adults and two juveniles were seen in Clay Co (Jorgensen 2002), in 1995, a family group was in Fillmore Co 3 Sep, and in 1998, two adults with two juveniles were seen 16-22 Aug 1998 at a small private basin in eastern Clay Co where an adult had been observed Aug 1994 (Jorgensen 2002). During the same period, 1992-1999, there were seven summer reports of adults, including pairs, in the Rainwater Basin (Jorgensen 2002) and one report in Platte Co in 1995.
Jorgensen (2002, 2003, 2012) summarized the breeding season observations in the eastern Rainwater Basin; there were six breeding records at three locations. Since then, there was no confirmed breeding 2011-2015 in the Rainwater Basin even though adults and pairs were observed somewhat regularly during summer. In 2019, family groups consisting of two adults and two juveniles were observed at County Line WPA, York and Fillmore Cos on 12 July and
Harvard WPA, Clay Co on 17 August indicating local breeding (Jorgensen nd Brenner 2019). Although these are the eighth and ninth breeding records for the Rainwater Basin (Jorgensen and Brenner 2019), variable water levels at Rainwater Basin wetlands may preclude regular nesting by this species in this region.
Since 2000, breeding has occurred at widespread additional locations.
A pair summered in the vicinity of Hat Creek Basin Ranch, Sioux Co, in 2002, but no young were seen. The adults returned in 2003 and raised two young, the family group foraging in meadow and hayed meadow stubble. The adults returned in 2004 but remained only until Jun because of the very dry conditions and lack of water (Larry Wickersham, personal communication). In the same area, along Bodarc Road, a pair with a colt was seen 14 Jun 2013.
A pair at Chet and Jane Fleisback WMA at Facus Springs, Morrill Co, began breeding in 2005, raising a colt that year, then 1-2 each year through 2011, but no colt was seen in 2012 and there were no reports 2013-2015, until a pair with a colt was seen 2 Jun 2016.
A pair was seen at Kiowa WMA, Sioux Co in 2009-2010, but no colts were seen until there were brief glimpses of probably two colts 21 Jun 2011; a colt was present 26 May 2012, but none were seen 2013-2014. In 2015 the pair had a half-grown young bird 16 Jul and two young were with the adults 10 Oct. Only one adult was seen there 11 Jun 2017, but an adult and colt were photographed there 25 May 2018 and adults were there 31 Jul and 1 Aug 2018.
A pair with two juveniles in Rock Co 15 Aug 2006 suggested breeding there; adults with two colts were present 18 Jun 2008. Breeding occurred at Hutton Ranch Sanctuary, Rock Co in 2013, where two colts were fledged but one was found dead and the fate of the other was unknown. Breeding again occurred there in 2017 (Gordon Warrick, NPS, personal communication) and also just west of there on private property; an adult in brown plumage was in the area 31 May 2018 and a pair of adults was there 25 Jul, but no young were seen. One adult was reported at Hutton Ranch Sanctuary 13-14 Jun 2019. Two seen near Twin Lakes WMA in southwest Rock Co 2 Sep 2018 may have been these birds; two were at Twin Lakes WMA 13 Jun 2019.
Paired birds have been in Knox Co around the confluence of the Verdigre and Niobrara Rivers for several years and have bred there; a pair was seen there 29 Jul 2017, and a pair seen earlier on 20 Jun at Bazile Creek WMA, about 3-4 miles east, were likely the same birds.
A pair with two young was seen 10 Jun 2017 at Agate Fossil Beds NM, Sioux Co; cranes were heard but not seen in mid-Jun 2018 in the same location. An adult with a chick was seen 7-8 miles further west at Agate 2 Jul 2018, possibly a different breeding pair based on the relatively young chicks seen.
In Saunders Co, reports of adults from a wetland one mile north of Lake Wanahoo in 2017 were suggestive of breeding there; one was there 1 Jul and three on 25 Jul, followed by several reports of three through 12 Nov; these reports may be of non-breeding near-adults (see below). Two brown adults were in the same area 21 Jun 2018.
An interesting sighting was the copulation of a pair of Greater Sandhill Cranes (A. c. tabida) along the Platte River in Hall Co 9 Mar 2017 (Caven and Buckley 2017). This date is about a month earlier and further south than previous egg dates and known breeding locations (see above) in Nebraska; however, as discussed below (see Comments), the use of wet meadows in the Central Platte River Valley is important in stimulation of pair bonding (Tacha 1988). In 2018, Malzahn et al (2018) documented the presence in the Central Platte River Valley of 7-8 cranes in nine locations 15 May-7 Jun, including two pairs at different locations 15 May. However, Malzahn et al (2018) noted that all birds had departed by 7 Jun, suggesting that the delay was needed for the birds to improve their physical condition before resuming migration.
There are at least 30 reports 20 May-28 Jul of adults, often in suitable breeding habitat, but without evidence of breeding; these are from Garden, Cherry, Holt, Boyd, Rock, Antelope, Dixon, Dakota, Garfield, Loup, Valley, Custer, Lincoln, Dawson, Furnas, Buffalo, Phelps, Hall, Seward, Butler, Burt and Saunders Cos. Most of these reports may be of summering sub-adults, as discussed in Spring, but some may be local breeders or failed breeders on the move. Two brown birds foraging in a flooded soybean field 24 Jul-18 Aug 2018 in Dakota Co may have been the latter. One at Eppley Airfield, Douglas Co, hardly suitable breeding habitat, 28 Jul 2015 was probably a wandering non-breeder.
Fall: Aug 27, 31, Sep 2<<<>>> Dec 1, 3, 4
Fall migration is markedly different than spring migration. Sandhill Cranes migrate quickly through the state, stop over for relatively brief periods and do not concentrate along the Platte River in central Nebraska. Lingle (1994) noted peak numbers are lower than 10,000, usually occur in the second half of Oct, and usually in the western half of the state. Rosche (1992) considered it “abundant to very abundant” in fall in the northwest. High Counts (below) are in the first half of Oct and indeed reflect a westerly distribution. Some 90% of fall reports are in Oct, 60% of these in the period 5-20 Oct (Lingle 1994).
Of interest is the observation that highest numbers in the east occur somewhat later, in Nov (see High Counts). It has been suggested that most Canadian and United States breeders migrate to the east of westerly-migrating canadensis, albeit with some overlap (Tremaine 1970, Krapu et al 2014). Sandhill Cranes are, however, uncommon in the east, generally occurring in small flocks of fewer than 100 birds, although following very strong northwesterly winds, an amazing 1200 were in eastern Lancaster Co 11 Nov 1998 and 336 over Blair, Washington Co the same day.
Most depart by mid-Nov although on occasion large numbers have lingered well into Dec, notably 5000 on the Grand Island CBC 15 Dec 1990 and 200 on the Kearney CBC 21 Dec 1971. There are only about 15 reports in Dec in addition to those discussed above, distributed statewide 3-27 Dec.
- High counts: 30,000 in Morrill Co 7 Oct 1994, 5416 in Scotts Bluff Co 16 Oct 1999, 5000 there 13 and 14 Oct 2005, and 5000 in Hayes Co 26 Oct 2005. In the east, 1200 in Lancaster Co 11 Nov 1998, 500 over Dodge Co 19 Nov 2015, and 160 over Seward and Lancaster Cos 16 Nov 2007.
Winter: Wintering has occurred in the Central Platte Valley (Lingle 1994); the winter of 2011-2012 saw an unprecedented 3000+ wintering in the Hall and Buffalo Cos area (Harner et al 2015). Again, in 2012-2013, between 200 and 1000 wintered in the Grand Island-Doniphan area; arrival of spring migrants was noted in the area 10 Feb, when numbers around Doniphan “increased dramatically”. Since the winter of 2012-13, the only report of apparent wintering was of a flock of 200 near Alda, Hall Co 9 Jan 2018.
In addition to the few Dec reports (see above), there are these additional reports of birds which may have wintered, notably these in Lincoln Co: 26 Nov- “winter” 1964, 7 Jan 1983, 8 Jan 1974, 12 on 8 Jan 2006, 14 Jan 1962, 17 Jan 1975, and 17 Jan 1979. Other reports are 18 Jan 2002 Scotts Bluff Co, 2-4 at Lake Wanahoo, Saunders Co 4-6 Jan 2019, 24 on 7 Jan 2006 Hall Co, and 6 Jan 2001 and 11 Jan 1994 Buffalo Co. Some of these Jan reports may be of early spring migrants (see Spring).
Comments: Sandhill Crane migration and stopover in Nebraska, and specifically along the Platte River, has changed over time in response to human activities. Prior to settlement by European Americans, Sandhill Cranes occurred in lower densities and were more widely distributed along the Platte River during spring and likely primarily foraged in wet meadows (Krapu et al. 2014). Unregulated and illegal hunting in the late 1800s and early 20th Century may have affected crane use on the river (Krapu et al. 2014). However, water development in the 20th Century was more impactful, reducing suitable roosting habitat (open wetted channel widths > 50 m) as woody vegetation rapidly colonized former river channels (Krapu et al. 2014, Williams 1978). By the 1950s, spring staging was apparently no longer occurring between Cozad and the confluence of the north and south platte rivers due to lack of suitable roosting habitat (Krapu et al. 2014). Water development and land conversion also reduced wet meadow habitats, but waste corn from farming became a dominant component of cranes’ diet. Presently, favorable roosting habitat is mostly maintained by mechanical clearing and consequently Sandhill Cranes have reliably concentrated in the same areas primarily between Grand Island and Lexington for many years.
Sandhill Crane use of the Platte River valley continues to change in response to changing land use and resource availability (Krapu et al. 2014, Buckley 2011). Waste corn availability has been reduced due to more efficient harvesting equipment, as well as competition from snow and ross’s geese (Pearse et al. 2010, Krapu et al 2004, Sherfy et al 2011). In response, Sandhill Cranes are, in some instances, traveling farther from river roosting sites or to areas not frequently used in the past (e.g., north of Interstate 80) to forage (Krapu et al. 2014). Future shifts in agricultural practices that influence availability of waste corn and changes in open river channel roosting habitat will likely continue to affect Sandhill Crane use in the Platte River valley.
Stopover duration in the Central Platte River Valley varies by “affiliation” (see Taxonomy) from 18-28 days, with longer distance migrants (mostly Lesser Sandhill Cranes) staying longer (Krapu et al 2014). Greater Sandhill Cranes arrive earlier, stay a shorter period, and leave earlier than Lesser Sandhill Cranes (Krapu et al 2014). During the stopover, the average crane gains about 0.5 pounds of fat (Lingle 1994).
Reddish or brown Sandhill Cranes are reported fairly often, often in winter and spring; at these times of the year, these birds may have skipped their pre-basic molt the previous fall, possibly due to some type of pathology, and are “stuck” in last summer’s rusty and now heavily worn plumage (Rick Wright, pers. comm.). A possible pathology is infestation with feather mites, causing a situation analogous to mange in coyotes (Gary Lingle, pers. comm.). Birds with serious mite infestations are weak and can be run down and captured on the run; the infestation is simply and usually successfully treated in bird rehabilitation (Dave Brandt, pers. comm.). Reddish birds seen in summer, such as pairs breeding in Nebraska, may have stained feathers resulting from rubbing their feathers with soil; the soil oxidizes and produces the red color (Joel Jorgensen, pers. comm.).
CBC: Christmas Bird Count
NM: National Monument
NPS: National Park Service
UNSM: University of Nebraska State Museum
WMA: Wildlife Management Area (State)
WPA: Waterfowl Production Area (Federal)
Andrew Caven provided numerous helpful comments that improved this species account.
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