Red-tailed hawks are on the rise at Seattle-Tacoma International Airport, which has one of the nation's most-aggressive bird-strike programs.
Falcon expert Bud Anderson tenderly cradled a red-tailed hawk in his arms, a leather hood covering its face to keep it calm.
Later that day, Anderson released the hawk in Skagit County, far from Seattle-Tacoma International Airport, where it had been caught in a trap meant to keep birds from being sucked into jet engines during takeoffs and landings.
It likely won't return.
Sea-Tac was one of the first airports in the country to hire a full-time biologist to address problems posed by birds. It's also the only airport in the country to use a particular Swedish-made trapping system that's considered more humane than other traps.
This year — for reasons Anderson and Sea-Tac wildlife biologist Steve Osmek can't fully explain — they have been seeing an inordinate number of certain birds, particularly red-tailed hawks.
Over the past 10 years the Port of Seattle, which operates the airport, captured 381 raptors, mostly red-tailed hawks, or an average of about 30 hawks each year. But already this year, through the first of November, the airport has captured 101 hawks.
Osmek doesn't know why there's such an increase but said it could be linked to our unusually cool spring and summer. He also said there are a lot more voles — tiny mouselike creatures that are attractive prey for the hawks — on the airfield than ever before.
"In 11 years, I've never seen as many voles," said Osmek.
At the same time, there's been a drop in starlings at Sea-Tac. Normally the airport traps about 1,200 starlings a year, Osmek said, but this year he'll be surprised if they trap 500, and he doesn't know why the numbers have fallen off.
While stories of bird strikes are common, Osmek said 99 percent of the time the strikes cause no damage.
One of the most disastrous exceptions came in 1995 at Elmendorf Air Force Base in Alaska. An AWACS surveillance jet crashed and all 24 crew members perished after Canada geese were sucked into the engines after takeoff.
Birds sucked into engines can break the fan blades or get caught in the compressor and starve it of oxygen.
One destructive bird strike happened in February 2004, when a plane taking off from Portland's airport hit five ducks, damaging one of the engines beyond repair. Cost to replace it: $2.5 million
Most often, though, birds sucked into an engine get chopped up and pass through without damaging the plane.
Airport officials typically learn of a bird strike when they find a dead bird on the runway or a pilot reports it.
At Sea-Tac this year, some 73 strikes within 10,000 feet of the airport have been confirmed, resulting in negligible damage to four aircraft.
Eighteen involved swallows, sparrows and warblers, the highest category by far. Six were red-tailed hawks.
Installed near the runways at Sea-Tac are three Swedish Goshawk Traps, which use live pigeons as bait. When a bird lands on one, the sides snap upward, enveloping the bird. Instantly, an email and text message goes out to Osmek and Anderson, telling them of the capture.
Osmek said the traps are much more humane than the systems most airports use, called a BC trap. That trap, which Sea-Tac also uses, traps birds by the feet, so crews need to collect them quickly so they don't hurt themselves in the trap.
What's unusual about the hawk captures, said Osmek, is that almost all are young birds that hatched last spring. The older birds are too savvy, he said.
The trapped hawks are then taken to Skagit County, where Anderson, a raptor biologist who founded the Falcon Research Group in 1985, releases them into nearby woods.
Anderson visits the airport on Wednesdays and if a hawk is captured he'll take it home with him, affixing the leather hood over its head to calm it.
The airport also traps starlings, which, when they fly in a large flock, can also be dangerous to airplanes.
Sea-Tac also has several pairs of so-called resident birds that live at the airport year-around but normally don't interfere with planes. They have yellow wing tags and radio transmitters so scientists can follow their movements. One resident bird was released in Skagit County and within a week was back at the airport.
The hawks that are released are marked with a blue tag; few of these ever return to the airport, Anderson said.
Airport officials ask anyone who sees one of the tagged birds to contact the airport by emailing wingtaggedhawks@portseattle.org.
Facts about bird strikes:
Most bird strikes occur during landings and below an altitude of 3,000 ft.
Since 1990, 23 people have died in accidents attributed to bird strikes involving U.S. airlines.
The most devastating bird-strike accident was at Boston's Logan Airport in 1960, when an Eastern Air Lines flight was struck by a flock of starlings during takeoff. The aircraft crashed into Boston Harbor, killing 62.
Sea-Tac bird experts say 56 different species of birds have been sighted at Sea-Tac. While crows are the most common, they cause the fewest problems because they're considered smart and avoid aircraft.
Gulls are the most-common type of birds that strike aircraft; Sea-Tac this year has reported two airplane strikes by gulls.
Source: Federal Aviation Administration
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