For the first time since 1975, no young whooping cranes took their first long-legged strides at Idaho's Grays Lake National Wildlife Refuge this spring.
Four years of drought convinced wildlife biologists that bringing more eggs to the remote refuge in eastern Idaho would be a waste of potential for one of North America's rarest birds.The project to bring whooping crane eggs from Canada's Wood Buffalo National Park south to Grays Lake, where they were incubated by sandhill cranes, attracted international attention.
The whooping crane story was the subject of a National Geographic Society television documentary and articles in the society's magazine. The egg transfer ended this year, but research focused on one of the world's two wild flocks of whoopers continued.
In a dramatic counterpoint, the experiment to establish a second wild flock of whooping cranes, long a symbol of wildlife conservation efforts, crossed a major hurdle.
The whoopers became an international conservation symbol because of their brush with extinction. Whooping cranes once nested from Iowa and Illinois north into Canada. The last U.S. nest was seen in 1889.
By 1941, the world's whooping cranes had dwindled to 21. Six were part of a non-migratory flock in Lousiana and 15 were part of a flock migrating 2,600 miles between Canada and Texas.
Stringent protection and a captive-breeding program at Maryland's Patuxent Wildlife Research Center helped rebuild the crane's numbers. In August, the total number of whoopers was estimated at 200 birds.
This spring, biologists watching the stately cranes observed the first mating ever at the Idaho refuge. The program, which officials hoped would establish a second, self-perpetuating wild flock, had failed to yield nesting pairs.
This year's success involved releasing a captive-reared female whooper at the Idaho refuge during the traditional nesting season. But while the once-captive female and a wild male mated, they did not nest.
Now the biologists hope to repeat that success with a plan to capture two female whooping cranes in the next few weeks.