WHAT KILLS BIRDS? Human activities: Bird Deaths
a year
Glass Windows
Dr. Daniel Klem of Muhlenberg College has done studies over a period of 20 years, looking at bird collisions with windows.
His conclusion: glass kills more birds than any other human related factor.

Bird Friendly Building Design - pdf

100 to 900+ million
House Cats
The National Audubuon Society says 100 million birds a year fall prey to cats. Dr. Stan Temple of the University of Wisconsin estimates
that in Wisconsin alone, about 7 million birds a year are killed by cats
 
100 million
Automobiles / Trucks
Scientists estimate the number of birds killed by cars and trucks on the nation's highways to be 50 to 100 million a year.
Those statistics were cited in reports published by the National Institute for Urban Wildlife and U.S. Fish and Wildlife Service.
 
50 to 100 million
Electric Transmission Line Collisions
Estimates made by the U.S. Fish and Wildife Service demonstrate millions of birds die each year as a result of colliding with transmission lines.
 
up to 174 million
Agriculture
Pesticides likely poison an estimated 67 million birds per year according to the Smithsonian Institution. Cutting hay may kill up to a million more birds a year.
 
67 million
Land Development
Suburban sprawl is a silent but deadly killer. The National Audubon Society says loss of bird habitat is the greatest threat to bird populations.
 
unknown
Communication Towers
U.S. Fish and Wildlife Service estimates that bird collisions with tall, lighted communications towers, and their guy wires result in 4 to 10 million bird deaths a year.
 
4 to 10 million
Stock Tank Drowning
U.S. Fish and Wildlife Service biologists and other conservationists believe that large numbers of birds inadvertently drown in livestock water tanks.
 
unknown
Oil and Gas Extraction
The U.S. Fish and Wildlife Service reports that up to 2 million birds died landing in oil pits to bathe and drink in 1997. Fish and Wildlife says netting has
improved that situation somewhat. There are no overall estimates for the number of birds affected by oil and gas spills, and oil and gas extractions (and transport.)
 
1 to 2 million
Logging and Strip Mining
Logging and strip mining destroy bird habitat. According to the National Audubon Society, habitat destruction is the leading cause of bird population declines.
 
unknown
Commercial Fishing
The U.S. Fish and Wildlife Service and the Ornithological Council report that 40 thousand seabirds per year are killed in the Gulf of Alaska
by longline fishing operations. These same sources say long lining and gill netting kill large numbers of birds in other parts of the country as well.
 
unknown
Electrocution (Raptors)
Experts estimate that more than one thousand hawks, eagles, falcons and owls are electrocuted on transmission lines and poles each year.
 
more than 1,000
Hunting
According to the U.S. Fish and Wildife Service, more than 100 million ducks, geese, swans, doves, shorebirds, rails, cranes, among others are harvested legally each year.
 
100 + million

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