<P> Cats hunt small prey, primarily birds and rodents, and are often used as a form of pest control . Domestic cats are a major predator of wildlife in the United States, killing an estimated 1.4--3.7 billion birds and 6.9--20.7 billion mammals annually . The bulk of predation in the United States is done by 80 million feral and stray cats . Effective measures to reduce this population are elusive, meeting opposition from cat enthusiasts . In the case of free - ranging pets, equipping cats with bells and not letting them out at night will reduce wildlife predation . </P> <P> Free - fed feral cats and house cats tend to consume many small meals in a single day, although the frequency and size of meals varies between individuals . Cats use two hunting strategies, either stalking prey actively, or waiting in ambush until an animal comes close enough to be captured . Although it is not certain, the strategy used may depend on the prey species in the area, with cats waiting in ambush outside burrows, but tending to actively stalk birds . </P> <P> Perhaps the best known element of cats' hunting behavior, which is commonly misunderstood and often appalls cat owners because it looks like torture, is that cats often appear to "play" with prey by releasing it after capture . This behavior is due to an instinctive imperative to ensure that the prey is weak enough to be killed without endangering the cat . This behavior is referred to in the idiom "cat - and - mouse game" or simply "cat and mouse". </P> <P> Another poorly understood element of cat hunting behavior is the presentation of prey to human guardians . Ethologist Paul Leyhausen proposed that cats adopt humans into their social group and share excess kill with others in the group according to the dominance hierarchy, in which humans are reacted to as if they are at, or near, the top . Anthropologist and zoologist Desmond Morris, in his 1986 book Catwatching, suggests, when cats bring home mice or birds, they are attempting to teach their human to hunt, or trying to help their human as if feeding "an elderly cat, or an inept kitten". Morris's hypothesis is inconsistent with the fact that male cats also bring home prey, despite males having negligible involvement with raising kittens . </P>

Where did the term cats game come from
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