Every year millions of dogs and cats end up in animal shelters because their owners have abandoned them. Thousands more become strays. In the United States alone the number of animals entering shelters is estimated at more than six million annually. In human terms that is the equivalent to the population of some of the largest cities in the world. About half of the animals that enter shelters are killed, because they cannot be found homes. Globally there are tens of millions of strays.

You get some idea of the scale and risk of the overpopulation problem if you work out how many animals can be born from just one female cat and her offspring. One cat can have five kittens three times a year – these kittens reach maturity, have kittens of their own and so on. In this way, half a million cats can be born in a little more than seven years! One dog, her puppies and their offspring can produce more than 60,000 puppies in six years!

People can help by making sure they spay and neuter their pets. It is also important to spread this message to family and friends. Animals that have been spayed or neutered may live longer healthier lives with fewer behaviour problems. They also tend to stay closer to home and are less likely to start fights with other animals.