Laura Erickson's For the Birds

In 1941, one of the rarest known birds on the planet was the Whooping Crane. Whooping Cranes are extraordinarily beautiful, and their haunting calls make listening as rich an experience as seeing them. Yet the species was brought to the very edge of extinction thanks to habitat loss and hunting. Only 15 individuals remained in existence at the beginning of the 40s, including wild and captive birds.

If the Whooping Crane had been a nondescript songbird, like the extinct Bachman’s Warbler, perhaps little time an. d money would have been spent saving it. But Whooping Cranes were simply too beautiful and too important for any but the most anti­ environmentalist to ignore. Since 1937, when Aransas National Wildlife Refuge near Corpus Christi, Texas, was established to protect Whooping Cranes on their wintering grounds, long before the Endangered Species Act was passed, the U.S. government was firmly committed to protecting this magnificent creature.

When the first settlers arrived in the US, Whooping Cranes bred in what is now the United States, but they quickly disappeared at the hands of the settlers: the final nesting in the US occurred in 1894 in Eagle Lake, Iowa. People knew about one nesting area in western Saskatchewan, but those, too, disappeared in 1922.

But a handful of cranes returned every year to Aransas. Where they bred was one of the great mysteries of ornithology until June 30, 1954, when a forest fire broke out in a remote comer of Wood Buffalo National Park, which lies in northern Alberta into the Northwest Territories in Canada. As one forester named G.M. Wilson was returning in a helicopter after battling the fire, he spotted two adults and one young Whooping Crane. A ground party set out the following spring to study the birds. A fascinating account of the first studies on these birds in the remote wilderness was written by Robert Porter Allen for the November, 1959 issue of National Geographic.

With protection on both the wilderness breeding grounds and on their wintering grounds, the group of cranes slowly increased. But Whooping Cranes are not highly prolific­ although females virtually always lay two eggs, very seldom does a pair fledge both young, and unless they lose their eggs very early on, they virtually never renest. By the 1980s, the population had grown to 29 or 30 pairs, but all of them were still breeding in Wood Buffalo and all were wintering in Aransas. A single oil spill or hurricane could destroy every individual in the world.

In the 1970s, the US Fish and Wildlife Service worked out a plan to add a new population of cranes in a new area, the American West. Researchers located nests in Wood Buffalo National Park and removed a single egg, replacing it with a dummy egg. This probably had only a very minimal effect on overall production of wild birds, since cranes seldom successfully rear two chicks. They brought many of these eggs to Grays Lake National Wildlife Refuge in southeastern Idaho, where they swapped them with Sandhill Crane eggs. The Sandhill Cranes raised the babies, and suddenly baby Whooping Cranes were growing up wild in the United States once again. These young birds followed their foster parents to New Mexico’s Rio Grande Valley. Everything looked just peachy, except for one critical problem. Cranes imprint on their parents. That means that the birds raising these young Whooping Cranes provided the image the Whoopers would look for when they chose a mate. As they matured and became ready to select mates 5 years later, they all wanted to breed with Sandhill Cranes. This would have had disastrous consequences if the two species had hybridized, altering the genome, but the Sandhill Cranes, too, were imprinted, and would only select a Sandhill Crane for their own mates. So the poor Whooping Cranes lived out their entire lives like Ismael, alone and lost, never finding requited love. For a bird that remains with its mate for life, and seems to show genuine devotion, this seemed a uniquely cruel and tragic fate.

Now the last of this sad population has died out. Now the US Fish and Wildlife Service, along with the International Crane Foundation and several other organizations is working on two new plans to save the Whooping Crane. Next time I’ll tell you how these are working.