Wildlife biologist Brad Allen spends plenty of time in the field studying many of the state’s birds. But as Allen can tell you, all bird habitat is not equal … and sometimes, birds end up hunkering down in places humans would rather they avoid.

That’s been the case this winter, as Allen has joined Bangor International Airport maintenance staffers in an effort to create a no-fly zone of their own.

The problem: Ducks.

BIA has become a pretty popular spot for our web-footed friends lately, and the colder the weather, the more ducks arrive.

“[BIA] drains water off the runway into these lagoons, which never freeze,” explained Allen, the Maine Department of Inland Fisheries & Wildlife’s bird group leader. “[Actually] it’s not really a lagoon, because that implies a pond. It’s a series of stream, culvert, stream, culvert, all the way to Union Street, and probably ultimately to the Kenduskeag [Stream].”

When the Penobscot River freezes solid, and when Fields Pond’s outlet stream is clogged with ice, ducks that spend the winter in the Bangor area end up looking for open water, which they’ve learned they can find at the airport.

“Because this water is coming from under the runway and all, it’s a little warmer than ambient temperature and it’s become a very popular roost for Bangor’s urban ducks when it’s very cold everywhere else,” Allen said.

And as you might expect, BIA’s maintenance crew isn’t too excited about hosting a monstrous flock of ducks so close to the runway.

“One time we went over there and there were probably 500 ducks over there, and we’ve moved a lot of those ducks to alleviate the air traffic danger, at the request of the maintenance crew over there,” Allen said.

On Wednesday, a trapping expedition yielded 27 ducks, a figure Allen said was low because mild weather has reopened the river and Fields Pond’s outlet. Over the course of the winter, he said the crew has trapped, banded and moved about 450 ducks. He said 96 percent of those birds are mallards, while 4 percent are black ducks.

Allen said Wildlife Services, a federal agency that deals with nuisance wildlife, especially at airports, has set up a trap in one of the culverts, and the trapping crews lure the ducks in for a free meal.

“When the ducks come in there in the evening to spend the night, a few of them will wander downstream and find a little trail of corn, and will follow it all the way into the trap,” he said. “Once they start eating, the rest of their buddies can’t help themselves and they go in the trap to get a little of the corn themselves.”

The result is a feeding frenzy among the ducks, who are later removed from the trap, banded, and moved to locations far from the airport.

How far is far enough? That question is still being answered.

“We’re trying to learn something. We’re trying to move some ducks to help the airport, and we’re also trying to learn how far you have to move them,” Allen said.

Trenton, it seems, isn’t far enough.

Allen said birds that were banded and moved to the area of the causeway to Mount Desert Island have already returned to the airport and been re-trapped.

Ducks that were moved to Harpswell, about 100 miles away, have yet to return.

While having a large flock of ducks near the airport isn’t desirable, Allen said the safety hazard doesn’t seem as severe as one might think.

“[The ducks] know the traffic pattern, fortunately,” he said. “They fly in and out of there without going across the runway. They’re fairly close to the National Guard helicopter operations, and that’s an issue, but they’re only coming in at dusk, so it’s predictable.”

Allen said the problem has existed for several years, but more ducks are using the airport culverts as roosting areas this winter.

A long-term solution would be to cover the ditches so that ducks couldn’t utilize the flowing water, he added.

In the meantime, trapping efforts will continue, especially if colder weather arrives and freezes up other popular roosting areas.

“And we’re hoping that when spring comes, the issue will go away,” Allen said.

East Outlet rules clarified

During the spring and summer, the East Outlet of the Kennebec River is a popular place for fly fishermen.

The season on that stretch of the river – which stretches from Moosehead Lake to Indian Pond – was recently extended, and some of the water is now open for year-round fishing.

The key point: Some of the water is open. Not all of it.

Unfortunately, the Department of Inland Fisheries & Wildlife’s Web site initially listed the entire three-mile East Outlet as open, and this week fisheries biologist Jeff Bagley clarified the situation in the DIF&W’s weekly fishing report.

Bagley pointed out that during the winter months, fishing is legal from the dam at Moosehead Lake to the yellow posts at the tail of the beach pool.

If the thought of wading in 34-degree water doesn’t bother you, now you know exactly where you can go to get in some midwinter fly fishing.

Coming up …

Ducks weren’t the only order of business Wednesday, when I met up with bird expert Brad Allen.

We also spent a few minutes talking about crows.

Specifically, several people had asked me about the sizeable flocks of crows that often soar over parts of Bangor at dusk.

Allen explained the behavior to me, and taught me quite a bit about the wily critters.

I’ll share some of that information with you Saturday … and pass along a few other items of interest.

jholyoke@bangordailynews.net

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