BIRD KILLERS: GLASS AND ARTIFICIAL LIGHTING

About 3 billion birds gone since the 1970s, a 30% population drop in North American birds, according to Cornell University’s Laboratory of Ornithology.  This has also resulted in more bird species listed as federally and/or state endangered or federally and/or state threatened. 

Some reasons for this drastic drop in bird population are: loss of habitat with never-ending development destroying nesting habitat and foraging habitat such mature forests, wetlands, open fields. 

In addition to habitat destruction, building designs and development include glass and artificial lighting, both of which are responsible for mounting bird kills.

THE BEST PREDICTOR OF LETHAL BIRD COLLISIONS: ALL-GLASS BUILDINGS 

There is an increased use of glass in buildings.  Glass in buildings kill hundreds of millions of birds every year in the U.S., especially during bird migrations.

Dead Birds after Colliding with Glass in Buildings

Unfortunately, glass is an invisible threat to birds.  By the 1960s, large glass windows became widely available.  By the 1980s, glass technology led to today’s glass skyscrapers.  Jacob Javits Convention Center in New York, built in 1986, is one of the worst buildings for killing birds, especially during migration periods.

Why do birds collide into glass?  Because birds have eyes on the sides of their heads and little depth perception beyond their bills.  Trees and sky reflected in glass are not discernable to birds, so they fly right into the glass and are killed.

SOLUTIONS

·       Put patterns on glass using decals, bird tape, ceramic dots, or ceramic inks, or apply paint to glass in a 2” x 2” pattern (Wild Birds Unlimited sells bird tape)    

·       Opaque, etched, frosted or stained glass, glass block and photovoltaic glass

·       Netting or stainless steel mesh covering windows.

EXAMPLES OF BUILDINGS DESIGNED TO AVOID BIRD COLLISIONS

·       Green roofs, such as at the Ford Rouge plant, attract birds but Ford’s Viewing Center was designed with patterned glass to avoid bird collisions

·       Edsel and Eleanor Ford House’s Visitor Center has bird-friendly glass

EXAMPLE OF RETROFITTING BUILDINGS

·       Glass in the greenhouse at the Edsel and Eleanor Ford House was replaced with patterned glass

·       Jacob Javits Convention Center replaced original glass with fritted glass and reduced bird collisions by 90%

ARTIFICIAL LIGHTING – ANOTHER BIRD KILLER

Artificial lighting was recognized as a problem since the late 1800s.  Birds collided into lighthouses, the Washington Monument (1885), Statue of Liberty (1886), and the Empire State Building (1930).