In an Autumn when bad news abounds for bird lovers, let us rejoice in the comeback of the sandhill crane, a good-news story if there ever was one.
In the mid-1800s, when settlers began moving into Minnesota in large numbers, the large, gangly birds were reasonably common. Early observers recorded them breeding in significant numbers in the marshes of central and western Minnesota. Huge flocks flew overhead in spring and fall migration.
But by the 1890s, market hunters wielding automatic guns shot the birds without restraint. The leggy avians were sent to the East Coast market to grace many a dinner table. The cranes’ penchant for foraging in harvested cornfields in large flocks further exposed them to exploitation. Hunters used hollowed-out corn shocks as blinds. They were easy to kill
Once numbers were low, the population did not readily rebound when placed under protection. Cranes do not mature until age two, and when they mate, produce on average only one chick per year. By 1932, when T. S. Roberts wrote The Birds of Minnesota, he believed immense flocks of migrating cranes were “probably things of the past.” Sandhill Cranes were so scarce that he sent his diorama artists Walter Breckenridge and Lee Jaques to Nebraska to collect birds for display—cranes were too rare in Minnesota.
In 1930, when Breckenridge wanted to shoot movies of crane courtship dance and nesting behavior, he located with difficulty a pair nesting in a Wisconsin farm field less than one hundred miles from Minneapolis. The farmer who owned the field reported that cranes had used the same nest site for 26 years.
But the Breeding Bird Survey found that with protection like the Migratory Bird Treaty Act of 1918, and habitat, cranes have proved resilient. Their population increased 4.5% per year in the time period 1966-2014. In Chisago and Isanti Counties, the birds are common enough that any local birder today knows more about crane behavior than the most diligent birders of the 1930s.
Cranes seek out marshes, wet meadows, and the edges of wetlands in which to make their large nest. They lay one to three eggs; typically they hatch two chicks, of which one survives. Vertebrates, like frogs, and invertebrates, like snails.
Cranes are known for their staging displays in which huge numbers gather before spring migration (in North Platte, Nebraska, for example) and fall flight (locally, at Crex Meadows, north of Grantsburg, Wisconsin. Twenty thousand sandhill cranes are at present gathered on the reclaimed pine barrens of Crex. The spectacle is noisy with crane music, and exuberant with flight.
The families that we observe during the summer as the chicks hatch, grow big and follow their parents will migrate together in the fall. They remain together during the winter months, and part only in the spring. If you have cranes nesting near you, you may well be greeting the same birds next April. Cranes can live 20-30 years in the wild, and up to 80 years in captivity!
(All photos by Gary Noren.)
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