Some of the wild animals in the forests of Silent Valley, Parambikulam, Nelliampathy and Attappady in the district are, it seems, not showing their true colours.
Forest officials say the increased presence of melanism in the animals in these forests requires a scientific study.
This sporadically occurring colour change has aroused keen interest in scientists and wildlife enthusiasts alike.
B.S. Bhadrakumar, an official of the Thekady forest range of the Nemmara forest division, close to the Parambikulam Tiger Reserve, took photographs of a melanistic spotted deer on Saturday.
Last week, the photograph of a black panther was taken from the Attappady forests.
White sambar
Albinism is also found among wild animals in these areas. A white sambar was photographed in Nelliampathy by P.A. Easa, a senior scientist at the Kerala Forest Research Institute, recently.
L. Namasivayam, secretary, Kerala Natural History Society, says melanism and albinism are seen among the wild animals, birds and butterflies in regions close to the equator where evergreen forests are found.
He says albinism in peacock has been found in the Ramana Ashram at Thiruvannamalai in Tamil Nadu since 1945. Even now, albino birds can be seen in the ashram.
But no scientific study has been done to find out the cause of the colour change, he says.
Dr. Easa says melanism is caused by a recessive gene, and the ecosystem of the habitat may not have any influence on the colour change. Melanistic animals can be considered genetic freaks.
The presence of melanistic tigers has been reported from the Simlipal National Park of Odisha and the Sunderbans of Bengal.
Genetic studies should be conducted to find out how different these animals are from others.
Another theory is of mismatch due to climatic change or an attempt by the animals to protect themselves from predators, Dr. Easa says.
P.O. Nammer, Head of the Centre of Wildlife Studies, College of Forestry, Kerala Agriculture University, says melanism is due to the result of excess production of black pigmentation. Melanistic animals are found more in dense forests.
Melanism will work to help the animal escape from predators in thick forests.
Genetic study
But a detailed genetic study should be conducted to find out its cause in the evergreen dense forests of Silent Valley, Nelliampathy and Parambikulam.
