Nearly 35,000 sandhill cranes have swooped into the Sulphur Springs Valley near Willcox in an annual migration from mountain states and parts of Canada, the Arizona Game and Fish Department reports.

The largest concentration of the big birds — with wingspans of up to 6 feet and a history dating to the Pleistocene nearly 2 million years ago — is an estimated 25,184 at the Whitewater Draw Wildlife Area near McNeal.

An annual crane count, conducted by Game and Fish earlier this month, also found thousands of cranes in the Willcox Playa area, the San Simon Valley, and at a site called Crane Lake. Hundreds of the birds were counted at other locations.

The cranes usually begin arriving in Arizona in mid-September to early October, said department spokesman Mark Hart. They typically begin leaving the area in a return migration in mid-February, but some may remain until the middle of March.

Usually flying out of their roosts at dawn, the cranes feed on grain from farmers’ fields and return from feeding between 11 a.m. and 4 p.m.

The birds have a distinctive call, often described as a loud, trumpeting sound.

SEE THE CRANES

One popular site for observing cranes is the Whitewater Draw Wildlife Area, which is managed by Game and Fish and open to the public with no admission fee.

To reach the Whitewater Draw area, travel southeast from Tucson to Tombstone and then drive south about 5 miles on Arizona 80 to Davis Road. Turn east onto Davis Road, drive about 21 miles and watch for a sign for the Whitewater Draw Wildlife Area. Turn south and go about 2 miles to the wildlife viewing area.

Contact reporter Doug Kreutz at dkreutz@tucson.com or at 573-4192. On Twitter: @DouglasKreutz.