IS IT possible for a "big cat" to survive in Scotland's climate? Yes. But I'm sceptical that any are. Let me explain.
These big cat sightings started when the Zoo Licensing Act was introduced in 1984, and it has been argued that people who had pet big cats then released them into the wild. The lifespan of a wild leopard or puma is a maximum of 15 years, they mature
at around three years and usually leopards have one to two cubs and pumas up to six, so if they have been living in the wild for all these years there would now be quite a number of generations at large, which poses the question: why have none ever been hit by cars or been found dead?
A lot of people who say they have spotted a big black cat say it was a puma. In fact, if it's black – truly black – it's not a puma. The puma, which is the biggest member of the small cat family – is usually brown. There has never been a recorded case of a melanistic (black) puma in captivity in Britain.
But let's suppose they were out there, what would they be breeding with? They could only breed with another leopard or puma. And what would they be eating? Well, there was a case in Africa where leopards used to be seen on the outskirts of towns but then disappeared. A field biologist was hired to have a look and discovered that they were living the same life as urban foxes – living under people's garden sheds and feeding on domestic pets.
There was a TV programme about the big cat sightings in Britain. They brought a reputable, reliable puma hunter over from America to examine all the evidence, and in his opinion all the evidence was of dogs or dog attacks.
If they are out there, they are managing to breed, eat, are never hit by cars or found dead, and are rarely heard. That's remarkable because a leopard's mating call is pretty loud.
• Graham Law is an expert on big cats, based at the Department of Zoology at Glasgow University.
