Blame it on the birds

CHICAGO — When animals are the prime suspects in a mystery, who gets on the case? In capers where feathers or fur are the smoking guns, the role of the crime scene investigator is often played by top natural history museums.

They can even tell when the perpetrator was from out of town.

The cockpit crew of US Airways Flight 1549 knew their plane had struck birds after taking off from New York’s LaGuardia Airport.

Both engines shut down and Capt. Chesley “Sully” Sullenberger had to ditch in the Hudson River — saving all 155 people aboard.

It was clear soon enough after the Jan. 15 accident that the guilty fowl were Canada geese. What was not known was whether they were migratory or homebody geese — a critical distinction as airports devise strategies to shoo them out of aircraft flight paths.

That’s where the museums came in.

The Feather Identification Lab at the Smithsonian National Museum of Natural History in Washington served as lead detective, with assistance from Chicago’s Field Museum.

“We try to tell people we’re here for a reason — and this case helps demonstrate that,” said ornithologist John Bates, who works with the Field Museum’s 480,000-bird collection. It includes inch-long hummingbirds, five-foot ostriches and everything in between.

Rows of cabinets on the 116-year-old museum’s sprawling second floor hold specimens of 90 percent of the world’s 10,000 known bird species. But it was the Field’s collection of 2,700 samples of Canada geese — including some that migrated from the eastern Canada region of Labrador — that was the key to cracking the case.

Field ornithologists sent Labrador goose feathers and tissue to the Smithsonian, where tests showed the birds to blame for the US Airways accident were the Labrador type — not New York varieties that largely stay put year-round on the city’s waterways.

The clincher was a test in which Smithsonian scientists tested stable hydrogen isotope values in feathers — telltale markers that indicate where vegetation eaten by the birds grew. Migrating Labrador geese have eaten grass from different areas than the stay-at-home New Yorkers, and that showed up in the tests.

The findings, published in the June 8 editions of the journal Frontiers in Ecology and the Environment, mean New York airports may have to develop one method to keep migratory geese away from planes and another for the birds that nest in the city.

“A lot of people say, ‘Who cares about knowing the bird type,’” said Carla Dove, the aptly named program director at the Feather Identification Laboratory. “But that’s critical. The strategies differ according to species. If you have starlings or turkey vultures, you deal with it differently.”

Authorities may manage resident birds by harassing and culling them or modifying their habitat. Dealing with transient birds may require more elaborate methods, including recording their flight patterns or employing sensitive radar that detects their movement over runways.

New York City officials said this past week the city will trap and gas as many as 2,000 Canada geese over the next few weeks. The Field Museum scientists have been called into a variety of investigations over the years.

Authorities have sought their assistance in identifying animals smuggled into the US and the feathers on headdresses brought in by tourists who may not have known they were fashioned from endangered birds, explained museum ornithologist Dave Willard. — AP