Snakes: India
This is a collection of articles archived for the excellence of their content. |
Malabar vit piper
Prakash Kamat, August 5, 2017: The Hindu
The Malabar pit viper is encountered less frequently in the Western Ghats, worrying conservationists
The Malabar pit viper, one of India’s many snakes found only in the Western Ghats may be responding to erratic monsoons and spells of water scarcity with a reduction in size. It is also less frequently encountered in the forests.
The many facets of the snake were on show at an exhibition titled ‘The Malabar Pit Viper – a wonder of the Western Ghats’ organised by conservationists, herpetologists and artists in Goa.
“It is for the first time that 35 conservation photographers, researchers and herpetologists have come together to showcase the uniqueness of this species,” said herpetologist, conservationist and member of the Goa State Biodiversity Board, Nirmal Kulkarni.
A flagship species of the ghats, he said, the viper was chosen because there is a lot of colour around it drawing visitors, to whom “we can talk about this and other snakes.”
The viper’s life-cycle is linked to water. But in the entire Western Ghats landscape, monsoon patterns are becoming erratic, affecting habitats and in turn the species. “Because altered monsoons affect water availability, the immediate impact on Malabar pit vipers seems to be reduction in size.”
“To prove a hypothesis like this we will need a bigger sample size and research done over, say, 15 years. But by raising concerns over size and diminishing numbers, we are raising a red flag,” said Mr. Kulkarni.
Population size in reptiles cannot be estimated easily. But frequency of sighting of species like the Malabar pit viper have definitely reduced. The likely reasons are irreversible habitat change, loss of freshwater ecosystems due to erratic rainfall and rise in monsoon temperatures, Mr. Kulkarni said.
Moreover, these snakes are live-bearers. Therefore, with large scale deforestation and death of females the impact on their reproduction would be big.
The Malabar pit viper is a single species with varied colour morphs (appearance). Research observations say this could be due to habitat adaptation. Wet evergreen forests have darker shades and dry deciduous, light ones. Proximity to water, age and prey base also have a role to play.
As of now no sub-species have been classified but future DNA systematics could split up the species by various ghat ranges.
Villagers know it as a venomous species and though deaths have not been reported, people call it “Chabde” (the one that bites). Those who suffer a bite take herbal medicine and sleep for long.
“This is our eighth year and we have been able to collect about 300 individuals. Once you have a large sample size, the study can have scientific strength,” Mr. Kulkarni said.
The pit viper initiative has four research stations and each has about 3 or 4 scientists. Wider access to photography has brought in citizens and volunteers too, who provide pictures and data.
Volunteers pay to help
“Half of surveyors are researchers and the other half people who pay to participate. We do the expeditions with that money,” he said. Except for technical support from the Viper Specialist Group of the International Union for Conservation of Nature (IUCN), of which he is a member, the initiative gets no external help. IUCN’s Red List puts the snake under ‘least concern’ as of 2013. The Goa-Karnataka tussle over Mahadayi water diversion may affect reptiles and amphibians, he said.
Characteristics
Mimicry to fool predators
Aswathi Pacha, January 22, 2018: The Hindu
From: Aswathi Pacha, January 22, 2018: The Hindu
From: Aswathi Pacha, January 22, 2018: The Hindu
It’s not easy being a snake in the wild. With dozens of predators, death lurks in every nook. So they must resort to some weird tricks in order to survive. Now, a report in Herpetology Notes describes how an Indian coral snake resorts to mimicry to fool its predators. The tropical snake Calliophis bibroni is a venomous species endemic to the Western Ghats.
In its infant stage, the snake develops a bright red colouration with black stripes, similar to another venomous snake, Sinomicrurus macclellandi.
Other snakes, too, exhibit this type of mimicry, with two or more species sharing the same danger signals.
Once the predator has learnt that red and black snakes are venomous, it will never touch any other species with the same colour pattern.
But the bright red colour that served as a protective shield of sorts in infancy would be a liability once the snake grows into an adult, as it would scare away its prey as well. To address this, the snake turns fully black in colour as it grows up, merging well with the surroundings. This is the first time such dual mimicry has been reported from India.
Another common type of mimicry is Batesian Mimicry, wherein non-venomous snakes copy the patterns of venomous snakes to fool the predator.
“The wolf snake, a non-venomous snake, has white stripes on its body resembling the venomous krait,” explains Dileep Kumar of the Centre for Venom Informatics, University of Kerala, and the first author of the paper on the coral snake.
Snakes are capable of using other tactics to distract the predator. “Oligodon snakes or kukri snakes are non-venomous snakes of South Asia. They are capable of twisting their tail and displaying their bright ventral side to distract the predator and save their head. Display of bright colours, or aposematism, is seen in many other species, including frogs and lizards. Some lizards have bright, coloured tails to signal that they are poisonous,” says Dr. Abhijit Das, from the Wildlife Institute of India.
Hissing and opening the jaw to display the colour of the mouth are among the other tactics. “Snakes can also puff up their throat when agitated. Some snakes are known to display a different, bright colour skin under their scales when disturbed,” points out Ajay Kartik, assistant curator at the Madras Crocodile Bank.
