Cats vs. Birds...

The birds are losing, more dramatically than anyone knew.  It's mostly feral cats causing the problem:

America’s cats, including housecats that adventure 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., who led the team that performed the analysis. Previous estimates of bird kills have varied, he says, but “500 million is a number that has been thrown around a lot.”

For wild mammals, the annual toll lies between 6.9 billion and 20.7 billion, Marra and his colleagues report along with the bird numbers January 29 in Nature Communications. The majority of these doomed mammals and birds fall into the jaws of cats that live outdoors full-time with or without food supplements from people.

“The results are remarkable, not only for the big number, but also for the proportion of deaths from feral cats,” says Gary M. Langham, chief scientist for the National Audubon Society. The study assigns 952 million to 3.1 billion bird deaths a year to these wild cats. “These numbers really elevate this threat to a new level.” 

Felines are land sharks...