Sandhill cranes are regularly found during the winter in the Sulphur Springs Valley of southeastern Arizona. Cranes that spend the winter in the Sulphur Springs Valley represent two populations, the Rocky Mountains and Mid-Continent.
During a period of rapid growth the young birds feed primarily on animals they can catch in the shallow water or adjacent uplands. In years when the marshes dry up before the young birds are able to fly, predators, especially coyotes, take a heavy toll. During years of average water conditions, young-or-the-year birds comprise about 10 percent of the fall population.
The Rocky Mountain population is made up of the greater sub-species, Grus canadenis fabida. The nesting range for these birds centers around Grays Lake National Wildlife Refuge in Idaho with other nesting sites in Wyoming, Montana, Utah, and Alberta. An estimate for this entire population based on a 1992 survey is approximately 20,000 birds. Winter range for these birds includes southwestern New Mexico, mainly the area surrounding Bosque del Apache National Wildlife Refuge, the Sulphur Springs Valley and northern Mexico.
The Mid-Continent population includes three subspecies of Sandhill; the lesser, G.c. Canadensis; the Canadian, G.c. Rowani; and the greater, G.c. Tabida. The nesting range of this population includes central and northern Canada, Alaska, and northeastern Siberia. This population estimated to contain approximately 500,000 birds, winters in Oklahoma, Texas, New Mexico, southeastern Arizona and northern Mexico. The Sulphur Springs Valley usually holds between 8,000 and 12,000 birds each winter based on an annual survey conducted by the Arizona Game and Fish Department. The 1996 Sandhill count, completed on January 3, recorded the highest total ever at more than 24,000 birds. Department biologists believe the unusually high number is a result of the availability of wet Arizona roosting areas that have attracted more birds than normal from New Mexico and Mexico.
Depending on habitat conditions, Sandhills begin to congregate in late August at local agricultural fields called pre-migration staging areas. Migration to wintering areas begins in September. Cranes typically migrate in a few long, high altitude flights, stopping at traditional stopover sites. Major stopovers for the Mid-Continent population include the Platte River in Nebraska and the San Luis Valley in Colorado for the Rocky Mountain population. Sandhills begin arriving in Arizona in early October and remain until late February when their return migration to nesting areas begins.
Wintering areas selected by cranes feature shallow water roosting areas with low or no vegetation. The Willcox Playa offers an excellent roosting area. Cranes winter in close proximity to harvested grain fields. Corn is preferred. Sandhills leave roosting areas in early morning, usually about sunrise, to fly to feeding areas where they spend 3 to 4 hours. Following feeding the birds fly to loafing areas, which may be the night roost site, other wetland areas, fallow fields or simply desert grassland areas. Sometimes the cranes return to feeding areas in the afternoon for an hour or two, but the afternoon feeding flight is much more variable than the morning flight. From near sunset until virtually dark the cranes return to roosting sites.
Sandhills usually begin nesting at about four years of age. First and second time nesters are not as successful as older birds. Nests, consisting of mounds of vegetation, are usually located in shallow marshes or wet meadows. Cranes usually lay two eggs, but it is unusual for a pair to raise more than one young per year.
Sandhills are overall gray in color with black feet, legs and bill, and a dully red patch of skin on the forehead. In flight, blackish primary feathers can be seen. Some cranes may stain body and wing feathers a rusty brown with mud containing ferric oxide. Wingspan is an impressive six to seven feet. Adult greater Sandhill cranes normally weigh 11 to 13 pounds. The Canadian subspecies is slightly smaller than the greater and adult lesser Sandhills average six to seven pounds. Cranes are a very vocal bird. Their loud, rolling rattle; garroooo garrooooo can be heard a mile away.
The most convenient place to observe Sandhills in the Sulphur Springs Valley is around Willcox Playa. Flight patterns change from year to year based on suitable roosting habitat and the availability of feeding fields. However, seeing Sandhills is relatively easy. Select a viewing site along Highway 191 from Cochise south to Birch Road on the west side of the Playa or on the east side from the Willcox Playa wildlife area south to Baker Road along Kansas Settlement Road. Be in position about 30 minutes before sunrise.
Binoculars and spotting scopes will be useful. Depending on the chosen location, Sandhills may fly directly overhead or a few miles away. Use a vehicle to follow the flight to the bird's feeding areas. Dirt roads are generally passable in a passenger car, however, stay off dirt roads when they are wet. Some roads are privately owned and require permission of the owner prior to passage. Please respect private property rights.
The Pearce-Sunsites area is famous for the annual migration of Sand Hill Cranes to the Willcox Dry Lake to the north of us. For more information about the annual festival, and birding in general, visit this site. http://www.wingsoverwillcox.com/