Chemical sends unwanted birds on a strange trip

Andrew Tellijohn

In an attempt to reduce the campus pigeon population, University Environmental Health Services was forced to use its last resort earlier this month: get the birds drunk.
Anyone who has recently noticed campus birds acting strangely might have stumbled upon a pigeon under the influence of Avitrol, a chemical added to corn or grains that affects the nervous system.
“(Avitrol) is a flock alarmant, whose purpose isn’t to kill, but to create a behavioral response that will be perceived by other birds in the flock to be frightening,” said Jay Bruesch, a technical director at Plunkett’s Pest Control Services, a company contracted by the University for pest control.
“Avitrol is designed to cause a flock of pigeons to fly away from an area so pigeons won’t use it for feeding or roosting,” he said.
Only after receiving numerous phone complaints about the number of pigeons — which happens an average of about twice a year, Rees said — the University’s Environmental Health and Safety Department mixes Avitrol with pigeon food.
“Some pigeons will die from it, but it’s designed more to disperse the flock,” said Kent Rees, a University Environmental Hygiene officer.
Generally, only old birds that are already sick or young birds will die after eating Avitrol, he said. Most birds just begin to act listless and erratic. Sometimes they emit altered voice pitches, scaring other pigeons away.
Betty Swindle, manager of Management Information Systems at the Avitrol Corporation, said Avitrol makes pigeons act much like a person in a drunken state, which frightens other birds. “The whole idea is you get a few of the birds to react and scare the rest of the flock away,” Swindle said.
The drug can affect other animals such as ducks, geese and squirrels, but they would have to consume much more Avitrol-laced seed than pigeons to suffer from ill effects, she said.
“In the proper dosage, the chemical in Avitrol is poisonous to all vertebrates,” Swindle said.
She said an animal’s weight, size and health determine the pesticide’s effects.
Bruesch said in the 14 years he has been in the pest control business, he has not heard of any pets or children harmed by Avitrol.
“I have never heard of a child or domestic animal getting their hands on Avitrol,” he said.
The Environmental Protection Agency and the Minnesota Department of Agriculture have both approved the pesticide’s use, Rees said.
To avoid harming other animals, pest control officials pre-bait an area. In pre-baiting, regular seed is scattered in a specific location in order to attract the target animals, such as pigeons. Gradually, the animals will routinely return to the area to eat.
“You try to teach the flock to feed from a certain area,” Bruesch said.
After the birds establish a feeding pattern, Avitrol-laced seed is scattered along with the regular seed.
Bruesch said pigeon-control is important in heavily populated areas such as the University because the birds can carry diseases.