Why Do Cats Eat (and Catch) Mice?

1 Why Cats Eat Mice

Mice are rich in taurine, which cats cannot synthesize on their own and must get from food. Adequate taurine supports the liver and eyes and sharpens night vision; a lack brings retinal degeneration and blindness, heart-muscle failure, poor bile secretion and digestion, reproductive failure in queens, stunted kittens, and a weak immune system. Fish, mice, birds, frogs, and livestock all contain taurine, but cats favor easy, fast-breeding, nocturnal mice as prey. In lean times mice were a staple; today’s pampered pets are well fed and have no nutritional need for them.

Cats are carnivores that actually prefer the taste of fat and prize high-quality protein, so salmon and beef beat mice easily — and those foods also carry taurine. Oldfield mice ate farmers’ grain and were even eaten as game, so they were safe then; modern rats lurk in sewers and dark corners on rotting, contaminated waste and teem with parasites and pathogens, so a fastidious cat avoids them given the choice.

2 Why They Still Hunt

Catching mice satisfies the predatory drive: cats are apex predators wired to hunt whether or not they are hungry, and some pets still keep that instinct. Hunting also burns excess energy — a restless cat may ‘zoom’ indoors, and since cats are active at night like mice, a darting mouse becomes a perfect playmate in a chase game.