Monday, August 16, 2010

RARE INSTANCE OF GREEN VINE SNAKE EATING A SHIELDTAIL SNAKE.




A rare instance of a Green vine snake (Ahaetulla nasuta) preying upon a Large scaled shieldtail (Uropeltis macrolepis macrolepis) was recorded by herpetologist Nirmal Kulkarni and his team in the Chorla Ghats forests of the Mhadei Bio region on the 15th of August 2010.

Interestingly, the Green Vine snake is a partially arboreal species of snake while the large scaled shieldtail is an inoffensive burrowing forest species that is endemic to the Western Ghats of India.

This is the second report of a Green Vine snake feeding on a shieldtail snake in the Northern Western Ghats of India, the first report being from Maharashtra by herpetologist and Curator of the Bombay Natural History Society Mr. Varad Giri a few years ago.

The Green Vine snake is uncommonly seen on ground and feeds mainly on lizards, frogs and small birds. It is a mildly venomous snake and the venom is capable of paralyzing small prey.

Shieldtail snakes are strictly forest species of burrowing snakes that are usually encountered under humus or leaf litter in dense forest habitats of the Western Ghats forests and are known to be highly elusive in most of their range. Encountered in thickly forested areas or on the fringes of forest habitats and open patches, Shieldtail snakes can be observed and studied only in the 4 months of monsoon period in the field, after which they burrow under the forest floor, sometimes even 2-3 feet in the soil. The specie documented in the Mhadei Bioregion includes the large scaled shieldtail, the pied belly shieldtail and the Elliot’s shieldtail.

There is a lacuna of knowledge about these species whose ecology and habitat preference is lest known merely from a few observations and hence the current observations of predator prey relationships with a partially arboreal species are considered important by researchers.

The team observed the large scaled shieldtail being caught at mid body by the Green Vine snake and pulled up from the leaf litter to 1 foot above the ground to be swallowed head first followed by the complete snake. The entire time span of the incident was approx 40 minutes after which the Vine snake proceeded to a higher branch at 5 feet above the ground and remained there for 20 minutes before moving again.

The approx length of the Green vine snake was 3 feet while the large scaled shieldtail was approx 12 inches. Non-intrusive observations and photo documentation were carried out to document the behavior of the two species and the observations are being reported to the Center for Herpetology as well as the Indian Herpetological society for information.

The incident was recorded at 630 meters above sea level in secondary forest vegetation and the skies were partially cloudy. The humidity at the time was 78 percent and the temperature was 28 degrees Celsius. Other data including GPS locations and the dominant vegetation in the area was Makad limbu (Atlantia monophylla) and False guava (Catunaregam spinarum). The nearest water source to the area was approx 4 meters away from the incident.

The team consisted of Mr. Nirmal Kulkarni and Mr. Krishna Gawas affiliated to the Mhadei Research Center and Mr. Sunil Patil a volunteer.

Nirmal Kulkarni

Email- ophidian_nirmal@yahoo.co.in.