A PhD student from Delhi University has discovered four new species of burrowing frogs in the Western Ghats, further cementing the region's place as a global biodiversity hotspot with an unprecedented rate of new frog discoveries in the last decade.
The findings are the result of five years of extensive research by Delhi University student Sonali Garg, and her supervisor Professor SD Biju, who is also known as the 'Frog Man Of India'. The species belong to the Indian frog genus Fejerarya, but are unique because of their ability to burrow using their hind legs.
Discovered in Kerala and Maharashtra, the frogs were confirmed as new species by using an integrated taxonomic approach that included DNA studies, detailed morphological comparisons and bio-acoustics. They include the Maohrahan's Burrowing Frog discovered in the Agasthyamala Hills in south Kerala, the Kadar Burrowing Frog, discovered in the Vazhachal forest in Kerala, the CEPF Burrowing Frog found in Amboli in Maharashtra, and the Neil's Cox Burrowing Frog found in the Parambikulam tiger reserve in Kerala.
"Burrowing frogs are very rare, cryptic and difficult to find. Only 7-8 out of the 230 frog species in the Western Ghats are burrowing frogs," Biju told HuffPost India. "While most frogs in the Western Ghats can be easily spotted during the monsoon, these frogs can be seen for only two to three weeks in June and July. Otherwise, they stay hidden underground or under wooden logs." This also makes these frogs the most susceptible to weather patterns. Since they only breed for a very short period of time, any changes in weather patterns can affect their numbers.
"Our study highlights a fairly common group of frogs that is usually found closer to human habitations but is still not documented properly. More extensive studies are required to scientifically identify and describe the Western Ghats frogs which are already facing extinction threats from various human activities," Garg, who conducted this study as part of her PhD research at Delhi University, said.
In February, Garg and Biju had announced the discovery of four news species of the world's smallest frogs in the Western Ghats. The frogs were so tiny that they could even sit on a finger nail.
There has been an exponential increase in the number of new amphibian species discovered in the Western Ghats in the last decade. Out of the 1581 new species of amphibians discovered between 2006 and 2015, the second-highest number were from the Western Ghats-Sri Lanka biodiversity hotspot, numbering approximately 159. Out of these, 103 were from the Western Ghats alone.
In fact, the number of amphibian species discovered in the Western Ghats habitat has nearly doubled within a short span of ten years. Biju attributes the region's biodiversity to factors such as the Western Ghats being isolated from the mainland, as well as the wide array of habitats found within it.
"If you look at the pattern of discoveries, you can see that only about 30-40% of the flora and fauna, especially lower forms of species, in the Western Ghats has been discovered or documented," Biju said. "I believe that we will have to wait for at least another 10 years to fully understand the diversity of life forms in this region."
However, about one-third of the frogs in the Western Ghats are already threatened by extinction. "Many of these frogs are extremely rare and found only in specific areas," Biju said. "Any small change in the habitat is more than enough to decrease their population."