(Q) My 11-year-old cat loves to stay outside overnight, which is fine with me as we live in quite a safe area. But how low does the outside temperature have to be to become detrimental for a cat? Obviously when the weather is really bad she is kept in, but I do worry about her in winter.
(A) Behaviourist Celia Haddon says: Being exposed to very cold temperatures for long periods is as dangerous to cats as it is to humans. Cats suffer from hypothermia, becoming unconscious just like humans do, and they can freeze to death.
An early experiment showed that cats can die if their body temperature falls below 16°C (60°F) - it should normally be about 38°C (100°F). Shorthaired cats that are elderly or in poor health will obviously be more severely affected by cold than healthy longhaired felines. And don't forget, the wind chill factor can make temperatures fall lower.
As a rough rule of thumb, if it's too cold for you to be outside for long periods, then it is too cold for your cat.
Cats trying to shelter from the cold often crawl into car engines where there is some warmth left over from when the car was last driven, so check underneath before you drive off when it's very cold.
Anybody feeding an outside feral cat colony this winter should make sure the cats have a well insulated place to sleep, more food to help them cope with the cold, and water that is not frozen.