A ‘talk’ near Karnataka’s Kali River led experts to a frog no one knew about. india news

Last updated:March 27, 2026, 16:46 IST

What made the black night frog difficult to identify was its similarity to existing species. This discovery was not limited to academic work only but was done by those working on the ground.

On a rain-filled evening near Castle Rock in Karnataka’s Uttara Kannada district, a slow, repetitive sound echoes in the forest. It blends into the background, indistinguishable from the countless other calls that define the Western Ghats.

No one paid attention to this for years. It was so familiar, yet unmistakable. Turns out it was actually pretty unique.

A new species of frog has now been named. Nyctibatrachus kali or black night frog has been formally described from the Central Western Ghats. The discovery adds to a region already recognized as one of the world’s most important biodiversity hotspots, and reminds that even well-studied ecosystems retain secrets.

A search in time of fall

Globally, more than 9,000 species of amphibians are known today. India has 474 of them, representing about 5.3% of the world’s amphibian diversity. Yet, nearly two out of every five amphibian species are at risk of extinction due to habitat loss, climate change, and disease.

In this background, discoveries like the black night frog have deep significance. Over the past 25 years, India has documented 256 new amphibian species, an average rate of about 10 per year. Each new species contributes to the understanding of the country’s ecological history and biodiversity.

A sound in the rain that gave birth to a new species in Karnataka

One day, during heavy rains in the forests of Uttara Kannada, CR Naik, Deputy Range Forest Officer (DRFO), Ankola Range, heard something that made him stop.

He recalls, “While riding my bike in heavy rain, I heard a familiar ‘talk’ sound. Out of curiosity, I turned back and waited. After some time, another sound was repeated.” “I happily went out in the pouring rain, waited, recorded its sound on my mobile and sent it to Professor Gururaja.”

At first the sound did not seem unusual. “After hearing the sound, he said, ‘It sounds like a croaking frog,'” says Naik. But what happened next would change this perception. “In the following days, when the team discovered through molecular analysis and acoustics that it was a new frog, I was surprised, delighted, and proud.”

when the familiar becomes new

To the research team, the frog initially appeared to be something already known.

“Initially when CR Naik sent me the recording of the frog based on my previous observations of Kathleen’s Night Frog, I thought it was the Kumbhara Night Frog,” says Professor Gururaja KV, Professor at Srishti Manipal Institute of Art, Design and Technology, MAHE. “However, acoustic and molecular analysis revealed that it is a new species of frog.”

That moment of improvement from hypothesis to evidence defined the discovery.

Professor Gururaja points out the unusual mix of field staff and researchers behind the discovery, saying, “It is interesting to note that citizen scientists are part of this discovery, and we have a long way to go in this direction because conservation requires collaboration of people, practice and policy.”

A species hidden in plain sight

Identifying the black night frog was difficult because of how similar it was to existing species.

“The new species Nyctibatrachus kali is morphologically cryptic but differs from all the existing 34 species in advertisement calls and genetics,” explains Arvind CK, a PhD scholar at Manipal Institute of Technology, Bengaluru.

He added, “This sound is similar to the sound of wood being chopped and is similar in sound to the sounds of other species in the N. sanctipalustris group.”

The difference is in the details. “Similar to other species in the group, N. kali also has two distinct advertisement calls, where one is a low-frequency call and the other is a high-frequency call. Both types of calls are different from other species,” he says.

A discovery built on field observation

This discovery was not limited to academic work only. It was shaped by those who worked the land.

Ramesh Budiger, Beat Forester, Yellapur Range, recalls early observations: “Learning about the sounds of frogs, their reproduction and their habitat, Professor Gururaja’s study team came to Castle Rock in 2021. On that occasion, when they were taken to a new place, they heard a frog croaking. They asked us to observe it, saying it could be the Kumbhara Night Frog.”

Over time, something bigger grew from that observation. “Later, we saw them at four places, and learned about their reproduction, we were extremely happy and proud. I was surprised when I learned that it was a ‘new frog’,” he says.

a species that is endemic to its habitat

The black night frog has so far been documented only in the Castle Rock area and is closely associated with the stream ecosystem.

“This species is currently documented only from Castle Rock, and is a stream-dwelling species,” says Arvind CK. “The conservation of N. kali and its habitat is very important and fragile. Stream networks and other stream-associated species are key here.”

more than a discovery

The finding also highlights the role of cooperation in conservation.

“I am extremely happy to note that the frontline staff of our forest department have played a very important role in the identification of this new species,” says Kumar Pushkar, IFS, Principal Chief Conservator of Forests (Wildlife).

listen carefully

At its core, the discovery of Nyctibatrachus kali Started with a moment of meditation. As Naik says, “We hope and want that we develop interest and inclination to listen to the forest as well as to see it.”

In a place as rich as the Western Ghats, sometimes that’s all it takes – to stop, listen and realize that what seems familiar may actually be completely new.