The feathers or other bird parts submitted are compared against a library of 620,000 bird samples, some gathered by Darwin and Audubon. Another contributor was Theodore Roosevelt, who collected birds around the family home in Oyster Bay, on Long Island, before he switched to hunting big game. And if the feathers do not make the case, the snarge goes to the DNA section, which has a huge database. Between the two, the success rate of identifying the type of bird involved is 99 percent.

And for high-profile crashes, identification both by feather structure and by DNA will be performed. A bird strike over the Bronx reported by the pilot minutes after Flight 1549 took off from La Guardia Airport may have caused both engines to fail, forcing the emergency splash into the Hudson, which all 155 people on board survived. The feather was discovered attached to one of the plane’s wings.

Researchers at the Smithsonian would not discuss their role in the US Airways investigation, but did talk about their work in other cases.

On a lab table under color-balanced lights, Dr. Dove opened a zip-top bag with some brown and white feathers from a recent bird strike involving an American military plane in Rota, Spain. In the field, investigators had identified the feathers as being from a long-eared owl, but putting one on the table, Dr. Dove saw that was not right. She reached for an eagle owl, a bigger bird of similar coloring. “See how nicely this matches,” she said.

For forensic ornithologists, it just doesn’t get any better than this.

Crash investigation is a relatively recent endeavor for the museum. “This collection started before there were even airplanes,” said Marcy Heacker, one of the museum’s investigators, referring to the vast repository of birds. But ever since an October 1960 crash at Logan Airport in Boston, in which an Eastern Airlines Electra hit a flock of starlings, safety investigators have called on the Smithsonian for help.