The report from the University of Nebraska concluded that bird loss due to homeless cats totals $17 billion damage based expenditures from hunters and bird watchers.
The study concluded that there are an estimated 60 million feral cats in the United States that are opportunistic hunters. The creatures don't lose their instincts for the hunt even if they are fed regularly by good Samaritans, and they tend to be a greater threat to wild native species of birds and rodents than they are to pests such as pigeons and house mice.
"Feral cats do kill some of these animals, but they are not effective in controlling populations because pigeons, house mice and Norway rats have adapted to living in close association with human and human-related disturbances," the report said.
The American Bird Conservancy said the report illustrated concerns the group has had for a long time about feral cats. The ABC said in a written statement that the practice of trapping and neutering wild cats was not enough to stave off serious damage to native bird and animal populations.
"A humane decision-making process on this issue must also recognize that feral cats live short, miserable lives because of disease, other predators, severe weather and traffic hazards," said ABC Vice President Daren Schroeder. "Thus their life expectancy is about one third as long as owned cats."
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