A very rare sighting: a melanistic (black) Serval cat hunting. We had three sightings of very rare melanistic (or black) Serval cats in Amboseli/Kitirua, Kenya. Two of them were very fleeting. On this occasion, this remarkable cat was visible for quite sometime as it hunted in the swamp. It was very distant and hence difficult to film. It was a rewarding sighting since we had spent many hours looking for it. We had seen the black Leopard last year so seeing the black Serval was an unexpected treat.
The Serval is a medium-sized cat with slender, long legs with a short tail and large rounded ears. Normally the colour ranges from golden brown, through yellowish-fawn to off white with pale underparts. There are numerous black spots and bars over the body. The tail has black bands. This melanistic or black Serval was mostly black but in the right light underlying dark spots were evident.
Serval cats stand 54-62cm at the shoulder and weigh 9-18kg. It is a solitary carnivore and its prey is varied and includes rats, frogs and insects. It sometimes catches small birds by leaping more than 2m into the air.
Melanism is caused by a recessive gene that when inherited from both parents results in over-production of the dark pigment, melanin. It is a rare feature widely reported for cats but its advantage (if any) to the cat is uncertain. Some have postulated that it results in a selective advantage for ambush. Others postulate that it may be an adaptation to higher altitude living (melanism appears more frequently at high altitudes) since black fur absorbs more light for warmth. An alternative hypothesis is that it provides resistance to some viral infections. It may well be a combination of all of these but no one knows for sure.