Colour camouflage in Kerala’s Parambikulam forests

Melanism found in some animals at the Parambikulam forests in Palakkad district of Kerala has caught the imagination of wildlife enthusiasts.

Recently, managers of the Parambikulam Tiger Reserve obtained photographic evidence of a pseudo-melanistic leopard. Earlier, a melanistic spotted deer was photographed. Though no photographic evidence has been obtained, black panthers too are said to have been spotted.

While the leopard was caught on cameras installed for monitoring the tiger, the deer was photographed by a forest official.

The black spots on the leopard were found closely packed to give it a designer coat. In the case of the deer, the white spots on its reddish fawn coat were overshadowed by the black pigmentation, giving the animal a blackish appearance.

Sanjayankumar, former Wildlife Warden of the sanctuary who photographed the deer, says the primary DNA analysis of excreta (pellet) proved that it was a male spotted deer

. Detailed genetic analysis could not be held as fresh pellet samples were unavailable and the animal was lost in the wild, he says.

The tiger reserve is in the southern part of the Western Ghats, down the Palakkad Gap.

It is located between the Anamalai hills and the Nelliampathy hills and the natural vegetation of the area includes tropical evergreen, semi-evergreen, moist mixed deciduous and dry mixed deciduous forests and moist bamboo brakes and reed brakes.

A.J.T. Johnsingh, former Dean of the Wildlife Institute of India, Dehradun, says melanism can be seen more in the evergreen habitat of the Western Ghats where the interiors of the forests are dark.

In such habitats, melanism should be considered an adaptation technique of the animals as they can stay unnoticed in the dark interior forests. Melanism is caused by a recessive gene and the ecology of the habitat does not have any influence on it. They should be considered genetic freaks.

Melanistic leopards are fairly common in many parts of the Western Ghats, but chital of that type is rare, Dr. Johnsingh says.

Ajith Kumar, course director of the postgraduate programme in wildlife biology and conservation at the National Centre for Biological Sciences, Bangalore, says there exists an increased possibility of melanism in dense and closed forest systems. Animals use it to merge themselves into the dark forest environments. Melanism has been reported from evergreen, moist and deciduous forests, he adds.

P.A. Easa, wildlife expert, sees these as genetic freaks unless proved otherwise. Presence of melanistic tigers has been reported from the Simlipal National Park, Odisha.

Genetic studies should be conducted to ascertain how these animals are different from the normal ones, Dr. Easa says.

P.O. Nameer, Head of the Centre for Wildlife Studies, College of Forestry, Kerala Agricultural University, observes that melanism will work to the advantage of preys and predators alike in a closed forest system. While it will help deer camouflage itself from predators, leopards can stay unnoticed from its possible prey. Genetic and ecological studies should be held in the Parambikulam landscape to know more about the animals, Dr. Nameer suggests.

The Parambikulam Tiger Reserve authorities are planning to install more camera traps in the sanctuary following the sighting of the melanistic leopard from deciduous forests.

Vijayanandan, Wildlife Warden of the reserve, says the survey will cover the evergreen forest areas shortly.

More such interesting information is expected to emerge from the survey, he adds.