The long-term plan is to include other creatures. "We started with birds, but it certainly can be expanded to include mammals and other animals," said Earnhardt. The database will prove a valuable resource as conservationists reevaluate priorities and look for smarter, more cost-effective approaches and tools.
Planning Reintroductions
Had this avian database been in existence in the 1980s, wildlife managers may have taken a different approach with trumpeter swans, using successful reintroductions of Canadian geese as a model.
The database promotes information-sharing. "The way you gather eggs, hatch eggs, and raise young would be transferable between similar birds," said Joe Johnson, chief wildlife biologist at Kellogg Bird Sanctuary. "We had to use a 'shotgun' approach because we didn't know what would work."
Some biologists tried placing trumpeter eggs under surrogate mothers of another species—mute swans—with limited results. Some reared cygnets by leading them around marshlands with a puppet "mother," at a cost of U.S. $500 per swan. Other scientists learned that survival rates jumped from 50 percent to over 70 percent by releasing two-year-olds instead of yearlings.
In any reintroduction, "the first assumption is that you've done the homework to see if reintroduction is a viable strategy," said Steve Thompson, LPZ vice president of conservation and science. Available habitat and safety are important considerations—and whether the species breeds well in captivity.
Then biologists must decide where, when and how to release birds. Some birds are "hard" released: biologists simply open the cage and let them go—a less effective, and less expensive method than "soft" release, where young birds live in a field aviary for some weeks. After release, they are given supplemental food until they adjust to their new surroundings.
Not a Panacea
Peregrine falcons have rebounded dramatically after decades of successful reintroduction. By the 1970s, the birds were nearly wiped out by exposure to the now-banned pesticide DDT. But it took three years for Tom Cade, founding chairman of the Peregrine Fund, to breed the birds at Cornell University in Ithaca, New York. They found that only hand-raised birds, not wild birds, nested in captivity. Now at least 300 pairs nest on buildings, smokestacks and bridges across the region.
By contrast, just 56 wild Attwater's prairie chickens remain. Their Texas grassland habitat has shrunk to less than three percent of its original size. The birds are difficult to breed. Reintroduction has not yet brought them back.
Restoring birds to their homelands is not a panacea. Some birds won't breed in captivity, and for many, there is nowhere left to live. "Clearly, reintroduction is not going to save every endangered species," Johnson said. "We don't have the time, the money, or the knowledge to save every bird on Earth, one at a time. If we want diversity of birds, we better save large chunks of the ecosystems that support them."
There the database has its limits. "It doesn't deal with the human component, the social, economic, or cultural issues like why we shouldn't poach, eat or kill these birds," Earnhardt says.
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