Keepers looking after the world’s smallest and most fearless species of cat are celebrating the birth of four tiny kittens the size of mice.

Rusty spotted cats are little bigger than rats when fully grown and the kittens were estimated to weigh 40 grams, a third of a domestic cat’s kitten, when they were born.

In the wild the rusty spotted cat, Prionailurus rubiginosus, is found in Sri Lanka and parts of India where it has evolved into two sub-species.

Little is known of its lifestyle or even how many there are in the wild, but keepers caring for the animals at Port Lympne Wild Animal Park in Kent describe them as fearless.

“A female with kittens will defend them without thinking of herself. They will quite happily attack us – they are so small we have to be careful not to tread on them, said Neville Buck, head of the zoo’s small cat section.

“In their own minds these cats are tigers – they think they are much bigger than they really are. They are quite fearless.”

The cats are kept at the zoo as part of an international breeding programme which aims to ensure the species has a fall-back population in the event those in the wild suffer a catastrophic crash or even extinction.

The cats, the smallest wild species in the world, live in forest regions and will attack and eat whatever they can catch, including rats and mice, birds, insects and frogs.

Because of their size, however, they have to be wary of being eaten themselves and it is thought they prefer hunting at night so as to avoid being snatched by birds of prey and bigger cats.

The first pair of kittens was born ten weeks ago to Palawla and the second followed three weeks ago. Lingam, the father of all the kittens, has now been introduced to a third female at the zoo. “We’re hoping he can score a hat-trick,” said Mr Buck.

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