A recent meta-analysis of 21 different studies of feral and domestic cats shows that previous estimates of how many birds and small mammals cats kill were lower than they really are, by 2 to 4 times. Your cute cuddly kitty is an adorable efficient killer: in the United States alone cats kill approximately 2.4 billion birds and 12.3 billion small mammals (mice, rats, voles, squirrels, chipmunks,…