The Bull Frog
Author: Rahul Alvares
Photo: Rahul Alvares.
The calls of bull frogs when they breed mark the arrival of the monsoon in India. During the breeding season, male bull frogs change their colour from dull olive-green to bright yellow and sport bright blue twin vocal sacs.
Every year in June, when the heaviest rains hit Goa, an army of bull frogs begins to call right behind my house. Their call, a loud and continuous ong owang, is nostalgic for me. I remember hearing it since my childhood days. Back then there were many more frogs and the combined volume of their cacophony was sometimes louder than the sound of the heavy rain pounding on the roof!
But over the years the number of calls have dropped. Frog hunting became a popular activity and it began to take a toll on their numbers. Bull frog legs are a prized delicacy in Goa and during these heavy rains villagers would often go out with large jute sacks to collect them. The hunting would take place at night and the amphibians would be located with torch lights. Caught in the strong beam of light, the frogs would be blinded, immobilised and become easy targets. Tens of hundreds of adults would be collected by a single villager in one night. Collecting the frogs at this time of the year had the added effect of destroying future generations since all the frogs captured were breeding adults that hadn’t yet reproduced.
The good news is that in the last few years, thanks to the initiative taken by conservationists and the Forest Department, the ban on frog hunting has been much better enforced in Goa. Now when the heavy rains first hit Goa, my colleagues go out hunting for frog poachers to arrest. As expected the number of frog poachers in Goa is reducing with every passing year.
The Indian bull frog is the largest amphibian in the country. Large females can often exceed 15 cm. from snout to vent. During its non-breeding period, this frog is relatively silent and often resides in wells. The bull frog’s non-breeding colouration is an olive green or brown with some spotting and barring. During the breeding season, males change their colour to bright yellow and sport bright blue twin vocal sacs.
In areas where there is a long and pronounced dry season, the bull frog aestivates, which is a kind of a summer hibernation. In sandy areas, it apparently burrows following the water table and can sometimes be found at depths of eight to nine metres!
Bull frogs will eat just about anything that moves and can be swallowed. J. C. Daniel mentions in his book The Book of Indian Reptiles and Amphibians that in addition to their normal diet of insects, this frog has been known to eat mice, shrews, birds up to the size of a pitta, snakes up to a metre in length, spiny-tailed lizards, toads, other frogs including smaller-sized frogs of its own kind and land crabs!
In fact, one adverse effect of over harvesting of bull frogs has been the subsequent increase in land crab numbers and a resultant increase in damage to wetland crops. Now who would have seen that coming?
Rahul Alvares, 34, is a wildlife consultant and snake rescuer based in Goa. He is also the editor of an online newsletter called The Creepy Times. Visit www.rahulalvares.com
First appeared in: Sanctuary Cub, May, 2014.