April 23 – In a messy but unsuccessful war against pigeons on city buildings, Denver has tried highfrequency sirens, electrified toe strips and an anti-perching product called Hot Foot. But now city officials think they finally have found a weapon that works: hallucinogenic chemicals.
For the past year, the city has been feeding pigeons corn laced with a substance called Avitrol, which sends birds into convulsions, sometimes fatal, that scare away the rest of the flock.
With so many pigeons on bad trips, city workers say it’s the first time in memory that people can walk without fear of plops from the ledges, windowsills and outcroppings of the ornate City and County Building and Greek Theater.
The acidity in pigeon droppings had become such a potent problem that the city is spending $100,000 this summer to power-wash bird scat from buildings around Civic Center.
“It got to the point where you felt like you needed ski goggles to look up at the City and County Building,” said John Hall, manager of public office buildings for Denver. “Pigeons are urban vermin.”
Though the same Avitrol chemical also is being used against pigeons at Coors Field, St. John’s Episcopal Cathedral and Rose Medical Center, not everyone is convinced it’s the No. 1 solution to the No. 2 problem.
Just a few blocks across Civic Center, state maintenance workers worry that Denver Mayor Wellington Webb merely is scattering pigeons from his building to do their business on the state Capitol.
And animal-rights activists are aghast.
“It takes 40 pigeons pooping all day in one place to equal what a dog leaves on my lawn in one drop,” said Catherine Hurlbutt, 87, who has rescued and nurtured hundreds of injured birds at her south Denver home. “You’re not supposed to say a bad word about dogs, but people think it’s OK to poison pigeons.”
When New York City residents started using Avitrol on pigeons, Grace Slick, the famed Jefferson Airplane singer of the ’60s drug anthem “White Rabbit,” protested to Mayor Rudy Giuliani in a letter.
“I have considerable experience on the subject of mind-altering drugs, and I can tell you that Avitrol is not your run-of-the-mill hallucinogen,” Slick wrote. “It causes violent shaking, trembling, thirst, nausea, convulsions, disorientation and a slow death. Wow, talk about a bad trip!”
Last year, the New York State Assembly passed a bill allowing cities to ban Avitrol, but Gov. George Pataki, heeding a request from Giuliani, vetoed the bill.
All the flap is over a 1-pound bird that was native to Europe but brought to North America in the 1600s.
Supporters call them rock doves, which mate for life and feed milk to their young, and note that their homing ancestors helped in World War II by transporting spy messages. Detractors liken them to rats and cockroaches that carry diseases and dive-bomb passers-by with fecal glop.
Denver has struggled for decades to keep Downtown pigeons under control. When workers put spikes on building ledges to keep pigeons from roosting, the birds simply built nests atop them and enjoyed air-cooled nests in the summer. When workers tried a chemical spread called Hot Foot, birds built new nests and enjoyed warmer roosts for the winter.
When world leaders visited Denver for the Summit of the Eight in 1997, city workers installed electrified wires atop ledges favored by pigeons at Civic Center’s outdoor Greek Theater. The wires suffered from frequent short-circuits.
High-frequency radio speakers were supposed to drive the pigeons batty, but the birds ended up perching atop them anyway.
City officials said their war against pigeons seemed lost – until Denver hired the Pigeon Man.
The latest owner of a 47-year-old family business called Bird Control, Doug Stewart said Avitrol is one of his most effective tools against pigeons. When he started working for Denver a year ago, the City and County Building was home to hundreds of pigeons.
But with a $250-a-month city contract, Stewart started sprinkling Avitrol-laced corn on the roof of city hall. Recently, Stewart scrambled across the roof of the four-story building with his monthly dosage of bait in his backpack.
While the rooftop view of the Rocky Mountains to the west and the state Capitol to the east was magnificent, Stewart was most proud of something he didn’t see.
There were few birds, or fresh droppings, anywhere.
So he laid down a few small piles of Avitrol-laced corn, which costs him $50 a pound, and talked about a job that has taken him across the rooftops of the city, from Lakeside Mall to the steeple at St. John’s Episcopal Cathedral – and some truly disgusting abandoned apartment buildings in-between.
“I get asked all the time: Am I killing pigeons?” Stewart said. “There’s no way in the world I want any dead pigeons. I want to keep them fat, happy and on the move. It’s good for my business.” According to the government-approved warning label, Avitrol is a “poison with flock-alarming properties, used for the control of feral pigeons in, on, or in the area of structures, feeding, nesting, loafing and roosting sites, in such a way that a part of the flock may react and frighten the rest away. Birds that react and alarm a flock usually die.”
Scientific studies show the chemical temporarily alters brain waves and throws the bird into spasms and convulsions. When an Ontario, Canada, environmental official banned the use of non-humane vertebrate pesticides in 1975, a team of University of Ottawa researchers concluded that Avitrol “appears to be humane based on scientific evidence.”
“Upon eating the active ingredient of Avitrol in a corncob base, the birds begin to flap wings, vocalize and convulse,” said the study led by pathologist Henry Roswell.
“Other birds seeing this activity in their colleagues become alarmed and fly away to another area.” Critics of the use of bird repellants such as Avitrol claim that their use merely shifts birds from one area to another.
Pigeon on a roof with solar panels with pigeon spikes to repel pigeons, Darmstadt, Germany
“Avitrol is not intended to kill birds. However, some do die, although the numbers are minimal in comparison to the hundreds that make up the flock,” Roswell said.
Death-rate estimates range from 1 percent to 20 percent of pigeons consuming Avitrol.
Meanwhile, workers at the Colorado Capitol wonder whether the city is dropping its pigeon problem on the state. In the past year, state workers have installed five special anti-pigeon Plexiglas barriers – at a cost of $300 each – on ledges above the Capitol’s west steps. When told Denver has been using a chemical that may be moving city birds to the state Capitol, state central services director Rick Malinowski said, “Thanks a lot! We may have to retaliate.”
City workers fear the consequences. At the city’s Greek Theater, maintenance worker Ray Martinez set down his coffee cup one morning on an outdoor step before walking inside an office.
When he returned to his coffee cup a few minutes later, he saw something that jolted him awake.
“I was ready to take a sip and I looked down and thought, “Hey, what’s going on here? I take my coffee black!’
” Martinez said. “I was so mad I threw my cup at that bird.”