Migratory Birds Dying In Droves In North America And Our Skyscrapers Aren't Helping

http://www.wunderground.com/news/whats-killing-migratory-birds-20140609

By: Robin Kemp
Published: June 9, 2014

Shiny skyscrapers define downtown cityscapes: reflective glass designed to mirror the passing clouds, giving the illusion of endless skies. For migratory birds, that illusion proves deadly: flying at full speed, they collide head-first – either dying on impact or falling to the ground where predators pick off an easy meal. And just as coastal lights disorient nesting sea turtles, so do urban lights lure night-migrating feathered travelers fatally off course.

According to Toronto-based FLAP Canada (Fatal Light Awareness Program), between 1.5 and 2 billion migratory birds die throughout North America each year, mostly from human-created problems. Although habitat loss is the leading killer, FLAP says, next in line is glass, especially in urban environments. Skyscrapers and multi-story office buildings are obvious culprits, but ground-floor lobbies, shop doors, plate-glass walls, car windshields and your windows at home also pose danger, according to ornithologists.

The problem is that birds recognize reflections as real space, not optical illusions. When a bird pecks and pecks at itself on the other side of your window, it’s attacking what it sees as another bird trespassing on its space.

When a bird can see through a window, that bird is in serious danger if it sees houseplants. When light doesn’t reflect off the glass, the ficus in your office lobby looks like a landing strip, and birds will try to hone in on it at high speed. They either hit the glass, break their necks, and die, or stun themselves, fall to the ground, and become prey for other animals.

The contemporary urban landscape in the United States and Canada acts as a giant obstacle course for birds traveling to and from South America. North America is home to four major bird migration paths, or flyways: the Pacific, Central, Mississippi and Atlantic. Those flyways aren’t completely precise, but birders have used them for generations to track migrating species.

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For night-migrating birds, many of which navigate by the stars, artificial light sources make the trip perilous. Light pollution, especially in urban areas, blots out most stars. The effect is like driving down an interstate where most of the exit signs have been removed. And if it’s cloudy, rainy, or both, FLAP’s researchers found, nighttime collision risk soars because the weather forces migrating birds to fly lower and much closer to buildings.

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Some companies make special bird-deterring mesh or window glass that gives birds a visual cue not to fly into windows.

Designers and architects have discovered ways to make buildings less hazardous by adding external grilles, ceramic rods, louvres, photo murals, fritting, frosted glass or netting. Some cities that have adopted bird-friendly building policies or guidelines are San Francisco, New York, Oakland and Sunnyvale, California. In Oregon, Lights Out Portland encourages offices and homes to turn off lights during nighttime spring and fall migrations.

The Audubon Society says climate change is forcing birds to migrate farther north. A 2009 report compared where birds spent their winters over a 36-year period with the average January temperature in the continental U.S. during that time. As winters got warmer, some birds consistently wintered farther north. While the Audubon Society points out this doesn’t mean climate change is the only factor, the fact that the correlation is so strong can’t be ignored.

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There are some simple things you can do around the house to help birds find their way. Some recommendations are as easy as closing your blinds so birds don't think they can fly through. You can also keep bird feeders at least 1.5 feet away from your home.

Office managers can install bird-proofing film and other deterrents on the building, or consider a lights-out policy on nights and weekends.

The Audubon Society offers more advice for making birds' paths a bit easier to navigate.