A study conducted by researchers from Wildlife Institute of India, Dehradun, on amphibians in the central Indian Panna Tiger Reserve has come up with a list of five species hitherto undocumented in this region. The researchers, apart from compiling an entire amphibian inventory of this region, have recorded a call library of eleven species and also have obtained molecular confirmation (through DNA) of the cryptic species – a term used to refer to species that appear the same but show up a difference when their DNA is examined.
“We need multiple techniques to correctly identify [cryptic species]… So there may be two very similar looking frogs. In the field we may mistakenly think they are one, but they may have completely different ‘calls’ or they be very different genetically,” explains Abhijit Das from Wildlife Institute of India who led the research and is an author of the paper published in Zootaxa.
Of the five species that the group has added to the faunal list of Madhya Pradesh are the dwarf toad found in peninsular India; Odisha paddy frog, an inhabitant of eastern India; wrinkled cricket frog, earlier observed in Karnataka; Pierre’s cricket frog, seen in Nepal, Bhutan and Assam; and western burrowing frog, earlier seen in western India.
Vishal Kumar Prasad, another author of the paper, conducted the field surveys with a team. Since Central India is dry, amphibians are spotted only during the monsoons (late June to early August).
In this window, the team spent 86 days over two years to study the area.
“We used to locate breeding aggregation of frogs following their ‘chorus’. Then we sit quietly at least 1 metre away from the frog with our call recording devices and make effort to record their complete call,” says Dr Das. Sometimes they had to repeat the measurements as the frogs were very tricky to identify.
First acoustic data
Among the achievements of the group is recording the advertisement calls of the western burrowing frog for the first time. This frog was identified for the first time in 2017 from populations in Gujarat, Maharashtra and Karnataka. “We have recorded 30 calls from three males which becomes the first acoustic data for this species,” says Dr. Das.
Among the total of 15 species studied by the group, 12 are frogs and three are toads. As Dr Das explains, amphibians are facing global extinction crisis due to climate change events, fungal disease and pollution related mortality. “But the point is that even if populations go extinct, we will hardly know about them.” A mere check-list is not sufficient and detailed field information is needed. Only then can we we get an idea of the behaviour and ecology of amphibian species from our forested areas.