From 21 wild birds to over 800: the whooping crane's narrow escape
By 1941 hunting and habitat loss had left just 21 wild whooping cranes, plus two in captivity. North America's tallest bird was a whisker from vanishing. Decades of protection and captive breeding have since pushed the total past 830, though most still belong to a single flock that shuttles between Texas and northern Canada.
The species once ranged across the American Midwest and south into Mexico. By the mid-twentieth century its only remaining nesting ground was the boggy northern forest of Wood Buffalo National Park, straddling Alberta and the Northwest Territories. That flock, about 560 birds, still winters on the Texas Gulf coast around the Aransas National Wildlife Refuge, and a refuge in Oklahoma serves as a major rest stop for most of the population each year.
Conservationists have tried to spread the risk. A reintroduction project in Wisconsin produced the first natural nesting there in a century, and roughly 140 birds now breed in Wisconsin and Louisiana, with another 130 in captivity. A Florida effort was abandoned after too many adults died and too few young survived.
Part of the difficulty is slow breeding. A pair nests on a raised patch of marsh and lays only one or two olive, blotchy eggs, each weighing about 190 grams. Incubation takes about a month, and usually no more than one chick survives a season. The parents feed it for up to eight months and stay together with it for about a year.
Adults are unmistakable: white, with a red crown, black wing tips and a long dark bill, standing up to 1.6 metres tall with a wingspan over two metres. Young birds are cinnamon brown. The loud calls that give the species its name can carry for kilometres, and mated pairs perform rhythmic duets at dawn and when guarding territory. The first such duet recorded in the wild was captured at Aransas in December 1999. Linnaeus gave the bird its formal description in 1758.
Source: Whooping crane
