Did you know that your seemingly gentle house cat Fluffy is a stone cold killer? It's true!
America's cats, including house cats that venture outdoors and feral cats, kill between 1.4 billion and 3.7 billion birds in a year, says Peter Marra of the Smithsonian Conservation Biology Institute in Washington, D.C., a member of the team that performed the analysis. That's a whole lot of birds!
To figure out how much wildlife cats catch, Marra and his colleagues combed the scientific literature for the best assessments of how many cats live in the United States and of what cats there and in similar climates hunt. Roughly 114 million cats live in the contiguous United States, 84 million of which share people's houses. Forty to 70 percent of those household cats do at least some roaming outside. Between half and 80 percent of those outdoor cats hunt.
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