'Lights Out' policies save thousands of migratory birds from fatal attraction
The link above has a really well rounded discussion of how turning down/off lights can help birds during migration - and how the ones who don't make it can still make a difference to science. The Chicago window monitoring methods are enviable, mostly due to the great participation they have. Other cities have a really hard time getting projects started and sustained.
The video, of course, starts with a drawer of really flashy not-North-American birds, but otherwise does well to be informative.
In case it gets bumped in the future, here's the text (apparently there's no way to embed the video):
'Lights Out' policies save thousands of migratory birds from fatal attraction
by Leslie Trew Magraw
March 17, 2011
Leslie Trew Magraw/MEDILL
The Chicago skyline has become less deadly since many of its most prominent members have adopted "lights out" policies during peak migration times.
As the Loop prepares to dim its lights to save thousands of avian lives, volunteers with the Chicago Bird Collision Monitors ready themselves to pound the city streets in the early morning hours to pick up migratory birds that have collided with buildings.
Mid-March marks the beginning of the spring migration season in the area, and most prominent members of Chicago’s skyline are instituting a “lights out” policy to prevent migratory birds from being drawn to the city’s glow.
“We know that the Lights Out program is inevitably saving thousands of lives,” said Annette Prince, director of the Chicago Bird Collision Monitors. “When cities are lit up at night, they attract birds to buildings that they would have avoided otherwise. They’ll circle [the buildings] and get confused. It’s a fatal attraction for them.”
Participating buildings turn down their lights from 11 p.m. to sunrise during the peak months of bird migration -- from mid-March to early June in the spring and from late August to mid-November in the fall.
Most song birds migrate at night using stars to navigate, the twinkling lights of the Chicago skyline disorient and distract, leading birds away from the open sky and into harm’s way.
The American Bird Conservancy estimates that up to a billion birds collide with buildings each year, making it a leading cause of death for thousands of species.
Joan Bruchman, a volunteer who canvassed the Loop looking for injured and dead birds with CBCM before buildings started dimming their lights, said: “When we first started, there were birds all the time. Now I find very few birds during the dark part of the [monitoring trip].”
A building doesn’t have to be tall to be dangerous to birds; it just has to have glass. Any building that has a window -- whether reflective or transparent -- can be a lure, according to David Willard, an ornithologist at the Field Museum.
Willard, who also acts as a bird monitor, said that the more glass a building has, the bigger risk it poses to birds.
“McCormick Place [which has one of the highest bird mortality rates in the city] is a kind of squat building – it’s only a couple of stories high – but it has an extensive expanse of glass,” he said.
For the past 34 years, Willard has circled the building each morning looking for the previous night’s casualties. “The total number being killed at McCormick Place because of lights being out is now a quarter of what it used to be,” he said.
Even though there has been a dramatic decrease in bird deaths since buildings have adopted lights out policies, other factors continue to pose problems for birds.
The collision monitors have been noticing that many birds are hitting buildings after first light.
Chicago offers green space along the lakefront and river that provide prime resting and feeding grounds for wing-weary migrants. Unfortunately, that puts them in “proximity to buildings with huge amounts of glass and dangerous reflections,” according to Prince.
Buildings that have landscaping either outside or inside can also act as lures for birds. “It’s the combination of having windows – and an attractive area for the birds to be drawn to in the mornings,” she said.
Willard said it’s often what is inside the buildings – and not the lights or the glass outside and what it reflects -- that draws birds into harm’s way.
“If you’ve got a bank with a big, essentially tropical, garden in the lobby and a bird that’s stressed after a night’s flight, those birds will see what looks like a great place to forage inside the lobby and have no way to know that there’s a pane of glass between them and it,” Willard said.
In addition to dimming lights at night, Prince said many buildings are dimming their lobby lights in the early morning hours, moving plants away from windows and putting temporary netting or paint on the windows during peak migration months.
“It will kill the best of a species and the worst of a species.”
Prince said many people rationalize the problem by arguing that bird collisions are somehow the result of natural selection – that it’s nature’s way of weeding out the stupidest or the weakest birds. She said that line of thinking is simply wrong.
“Glass is something that [birds] have not been evolved to understand,” she said. “Birds have been here thousands and thousands of years, and we’ve had glass skyscrapers for what’s just a drop in the time span of these birds’ evolutionary history.”
Many scientists believe that studying bird vision could lead to insights about how to improve glass so that it will pose less of a problem for birds.
Since birds see in ultraviolet, some manufacturers are making glass that reflects light in that part of the spectrum. Willard said, “There’s some thought that you could put patterns in the glass that would have no aesthetic effect on how you or I would see the building – and the bird would see something that looks like a window screen or bars or something [that would tell it to avoid the glass].”
Guardian angels for birds
Chicago Bird Collision Monitors volunteers help salvage some of the birds that had been injured after colliding with downtown buildings. The group operates as a non-profit sister organization under the banner of the Chicago Audubon Society.
Each migratory season, the monitors rescue thousands of stunned birds and take them to Willowbrook Wildlife Rehabilitation Center in Glen Ellyn for treatment and release. Prince, who has headed up the all-volunteer organization for the last five years, said approximately 80 percent of the birds taken in for treatment survive to fly another day.
Volunteers typically start their rounds before dawn and then circle back to check for dead and injured birds once the sun has risen. Having to wake up early can wear on the volunteers.
Glenn Gabanski, a retired math teacher who has volunteered with CBCM for more than five years said: “Some mornings I say this is the last year I’m doing it. But here I am starting up again. It’s because of the value to the birds and also to the value to science, that I keep going.”
The group operates an emergency hotline (773-988-1867) and encourages people to report injured birds.
“I think the reason that we’ve been able to respond and pick up as many birds as we have been is people know about it. People are happy to call the number,” Prince said.
She said that many of the calls come from building managers, security guards, doormen and people who work or live downtown. “They’ve had a long history of seeing these birds at their buildings – and they will call us to come help,” she said.
Prince said the first step in saving an injured bird’s life is containing the bird and moving it to safety until a volunteer arrives to take it to a rehabilitation center. “Half the battle is getting the bird picked up,” she said. “If they’re laying in the street, they can be run over by cars. If they’re on the sidewalks, they can get stepped on. They’re so small and unnoticeable that it’s easy to miss them.”
There are non-human dangers for injured birds, too. “Predators come in the mornings looking for these injured birds,” Prince said. “The crows and the gulls go up and down the same areas that our monitors go.”
The collision monitors are interested in recovering both the injured birds and the birds that have already died. The fallen birds are taken to the Field Museum where they become part of the museum’s specimen collection, are stripped down to a skeleton and added to a sample set used to study changes over time, or prepared and shipped out to be incorporated into other scientific research projects.
Willard oversees the birds once they arrive at the museum. "[They] give us a much more complete understanding of the biology of birds," he said. "Because as much as is known, it's still surprising how much isn't."
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