Thursday, March 19


World Frog Day on March 20 celebrates the role of frogs, the world’s most numerous amphibians. They live at the interface between freshwater and terrestrial ecosystems, eat insects and in turn get eaten by other vertebrates, and are thus crucial in converting insect biomass into vertebrate biomass.

Losing them can mean a boom in insects that prey on plants as well as a depleted food base for many terrestrial vertebrates, which in turn can irreparably damage both freshwater and terrestrial ecosystems. Unfortunately for the earth, since the 1980s, frog and other amphibian populations have been on the decline worldwide. In 2023, the International Union for Conservation of Nature (IUCN)’s Global Amphibian Assessment Report said 37 species have become extinct and continue to decline, making them the most threatened vertebrate group.

The most prominent historical driver of amphibian decline has been chytridiomycosis, a fungal disease caused by Batrachochytrium dendrobatidis and Bactrachochytrium salamandrivorans in frogs and salamanders, respectively. This disease affects their skin — an organ that protects them as well as allows respiration and exchange of ions to maintain electrolyte balance. In the last two decades, more than 60% of amphibians globally have been affected by it — although intensive monitoring and conservation efforts have reduced the extinction risk of 63 species, halving the impact.

Today, however, the most important drivers of extinction are climate change for 39% of species and habitat loss for 37%.

The Indian scene

India is home to more than 450 amphibian species, and roughly a quarter of them are categorised as ‘threatened’ and one-fifth as ‘data deficient’. The burden of B. dendrobatidis and B. salamandrivorans fungi in India is substantial but it has not caused mass mortality the way it has for frogs in the Americas and Australia. 

B.dendrobatidis and B. salamandrivorans both had their roots in Asia and spread worldwide through the trade on frog legs and salamanders as pets. In 1987, after Humayun Abdul Ali from Bombay Natural History Society published a scientific report highlighting their role in controlling agricultural pests, this trade was banned. However, by then, frog and salamander populations had been significantly affected as B. dendrobatidis had spread from Asia to Europe, the Americas, and Australia.

The situation in India itself is rather unique. Until 2015, scientists were unsure of the status of B. dendrobatidis; a diagnostic test emerged only in 2023. That said, while scientists in the country have not documented mass die-offs, they also haven’t found the status of amphibians to have improved in the last two decades. Since they lack long-term monitoring data for any species, it is difficult to pinpoint the causes.

In fact, India hosts a significant share of the world’s ‘data deficient’ amphibian species. And of the 157 threatened species in India, only six are protected under the Wildlife Protection Act 1972.

Climate change in India also presents a serious challenge. One well-known consequence is the mismatch between seasons and the natural rhythms of plants and animals. So a false cue of an early monsoon followed by a prolonged dry period can result in catastrophic breeding outcomes. At the same time, thanks to the lack of long-term datasets on surface water availability and amphibian populations in the region, scientists are also unable to predict the effects of climate change on them.

A time to care

The monsoons arrive at India’s shores predictably every year and are synonymous with the frogs’ chorus, when the adult males call out for mates. The females mate with several males and deposit their eggs in the water. The intensity of breeding frenzy wanes rapidly thereafter, when some laggards and first-time breeders might take a shot at breeding. While not all adult amphibians successfully breed every year, the intensity enhances the population’s chances of survival.

The breeding activity is focused on producing many tadpoles, which then engorge themselves on the luxuriant growth of algae in water bodies and grow quickly. They metamorphose into small froglets and hop on the land. In this phase, many lose out as they become prey to animals. Because of their short lifespan, the timing of their complex breeding behaviours with rain, and the availability of surface water in streams and puddles, is critical.

Other important conservation efforts include the creation of the salamander sanctuary in Jorepokhri in West Bengal in 1985 (although it does not support a breeding population at present), the University Grants Commission banning the dissection of frogs for educational purposes in 2011; and the ongoing conservation breeding programme for Himalayan salamanders at the Padmaja Naidu Zoo in Darjeeling.

Avenues to participate

There have also been more success stories of late. These include the Mapping Malabar Tree Toad Project, a citizen science project, coordinated by K.V. Gururaja in the Western Ghats; the Amphibian Recovery Project by S. Harikrishnan of the Wildlife Trust of India in Munnar, Kerala, with the Kanan Devan Hills Plantations Company Pvt. Ltd.; and the Himalayan Salamander Conservation Project led by Barkha Subba, in which she has involved the locals in protecting habitats. The CSIR-Centre for Cellular and Molecular Biology (where the authors are employed) has also been running a long-term programme to monitor stream frogs, in collaboration with the Maharashtra State Forest Department in Tillari Conservation Reserve.

The Padmaja Naidu Himalayan Zoo and the Nehru Zoological Park in Hyderabad also prominently display amphibians in their collection of animals and spread awareness to visitors. There is also a growing number of young professionals implementing conservation programmes.

For a nation that embodies its conservation values in its Constitution, citizens have many avenues to participate: for instance, one can take a few minutes of their time to record their calls or take photographs of both healthy and sick frogs following ethical guidelines and share them on citizen science portals like iNaturalist. Such efforts will help us move beyond a few charismatic species such as tigers and pandas.

The monsoon will arrive in a few months and we should play our role in amphibian conservation.

Karthikeyan Vasudevan is a Chief Scientist at the CSIR-Centre for Cellular and Molecular Biology, Hyderabad. He is a herpetologist who works on amphibian disease ecology.

Published – March 19, 2026 08:00 am IST



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