It was a hot winter day in the forests of Kudremukh National Park and as I write this, I reminisce that day, exactly five years ago on the 30th of December, 2010. We were hiking up the trail of Gangamoola with 30 enthusiastic kids and their stern faced teachers from the nearby town of Ujire, accompanied by Dr. Aravind and Abhisheka who were instructors for the nature awareness program. The hike up to Gangamoola was to show the importance of forests and how streams sustain all of life. It was to blow their minds by showing how the small trickle was actually the source of the mighty river Bhadra, which sustains millions of lives before reaching the Tunga.
Progress was excruciatingly slow. We stopped at every little spider or a mystic orchid with intent to make the kids think and question what they saw. Being from the town of Ujire, the forests were not new for them. Training those youngsters in perceiving the forest with intent of questioning the status quo was our task. As we reached the trickle that was Gangamoola, Dr. Aravind and Abhisheka had kept the students engaged with hill stream fishes. I got a little adventurous and began hopping over boulders and soon, found a crevice. Back in those days, I could fit into narrow nooks and crannies and slipped myself in easily. Down below, there was almost a labyrinth of networks where, in the monsoon, water would be gushing right through. Being the lean period, I could walk around and shining my torch, I made my way. A small black frog caught my attention. Inching closer, I realized that it was a rare and endangered toad, Ghatophryne ornata or the Malabar Torrent Toad.
The Malabar Torrent Toad Ghatophryne ornate
I took some quick pictures and called out to Dr. Aravind. The crevice that I had slipped myself in would not have been comfortable for all of them and I decided to take the frog out and show it to everyone. The frog was rather an enigma back then. Described by Günther in 1876, this toad was rather weird. It lived in torrential streams and was known to be found only from the Brahmagiri hills near Coorg. The Malabar Torrent Toad was placed in a group of frogs in the genus Ansonia. This genus was related to other toads like the Common Toad, Duttaphrynus melanostictus. These nomenclatural assignments were based on morphological similarity and only recently, scientists have been resorting to other forms like computer tomography or DNA based assignments. Now, we have always learnt that frogs and toads are different because the former is slimy and soft and the latter is rough and does not depend on water. But strictly speaking, toads are frogs. They both came from common ancestors and are only different from each other as are two families of frogs. The question that begs an answer is—what for did the toad adapt to living in fast flowing streams?
Torrential streams of the Western Ghats where toads are found.
And that was exactly what the kids asked too.
To be honest, a short answer would mean “I don’t know”. But a long one would mean that during the course of evolution, selection pressures pushed different groups of frogs to evolve differently and figure out a way to survive. Only a year ago, two papers had been published based on DNA: one of them by Dr. Bocxlaer and her team showed for the first time that a whole bunch of frogs evolved within the Western Ghats. This was facilitated by the long periods of isolation and suitable climate during the course of earth’s geological history. In a subsequent paper, Dr. Biju and his team picked up from where Dr.Bocxlaer had left off and erected a new genus called Ghatophryne and placed two species Ansonia ornata and A. rubigina under Ghatophryne. The word Ghatophryne takes its origins from the words ‘Ghats’ which means ‘steps’ in Sanskrit, referring to the Western Ghats and ‘phryne’ meaning toad in Greek. The two species are endemic to the Western Ghats as well. The Malabar torrent toad was indeed beautiful. Its forelimbs were rather dainty and long, the skin was rough and dry. The hind feet have moderate amount of webbing. All this indicted that the frog was not adapted for an aquatic life. What was striking was the coloration. It was a big surprise for us to find the wonderful colors on its underside. It had a wash of yellow with bright red spots all over its dorsum.
Frontal view of G. ornata showing bright underbelly
The child-like curiosity and the pleasure of finding things out was ignited in all of us. Like the kids, we too were now asking questions. Why on earth were there such bright colors on the dorsum of an otherwise dark and disgusting animal? We did not know! We instructors were more elated than the kids on our new find and before we harmed the frog too much, we left the place. We finished our work and wound up in Bangalore by the 31st of December. The year 2011 began and bid adieu. I did not cross paths with the torrent toad up until the November of 2012. And yet again, it all happened serendipitously.
I was invited by Thomas Vattakaven of the India Biodiversity Portal to make a visit to a place called Madhuvana and do a bio-blitz: basically to go out there and document all forms of life over two days. It being Deepavali and with an urgent need to get away from the polluted city, I said yes. I asked Vinay, my cousin to accompany me. Madhuvana was just outside of Gudalur in Tamil Nadu. We passed right through Bandipur National Park to get there. The survey location was a small tea estate and was nestled within the mountainous region abutting Neliampathy in Kerala. It was dark when we got there and we went straight to bed. The next night, we walked down to a stream and looked for frogs. We found numerous pit vipers and all of a sudden, Vinay shouted that he saw something. He was new to frog watching but is a good spotter. I was diligently hopping on rocks to not get wet but decided to risk it and waded through the stream. Vinay pointed at what he was looking and there it was. Another Malabar Torrent Toad and just like the previous time, we all were elated. Soon we saw a few more individuals. This time around, we had time on our side and spent a good hour and half observing and photographing these frogs. The toads have bright red spots in what can be called the arm pits and the crotch. The base of the jaw has a bright yellow spot. They cling on to rocks with thin film of water and are often found on moss-laden boulders or in small crevices.
Side view of G. ornata
I had learnt that these frogs were not as enigmatic as they were thought to be. Like most other frogs, no one had gotten out there and looked for them and hence, no one found them. The Malabar Torrent Toads are however listed as endangered by the International Union for Conservation Nature (IUCN). Their population is said to decrease across their range and the remaining populations are threatened deforestation. Largely by expansion of coffee and tea estates, resulting sedimentation of streams and chemical run off. Apart from this, we had no other information on these endemic toads.
The play of colors on G. ornata.
It was not until two years after, in 2014, that I stumbled across this frog again. Entirely by chance.
I was leading a bunch of young researchers this time in Coorg. We were in search of a frog that breeds in bamboo and were staying at the Honey Valley estate. This place is a frog photographer’s paradise and almost every other frog photographer has been there. We were told to keep an eye out for the Malabar Torrent Toad but we never saw one, until one evening when we stumbled across them in a nearby stream. As soon as we saw one, we looked around and we saw as many as five individuals on wet rocks. They seemed to be vocalizing but since we did not know how their calls sounded, we did not realize it was them calling. We spent time photographing them. We felt that the underbelly patterns were unique for each individual. Sometime later, I saw another individual in a tree hole by the stream. We looked for any eggs or tadpoles of this species but did not find any. We packed shop and returned back to Bangalore, only to visit Honey Valley again a few months later. In July 2014, I was again by the stream with the researchers, my thesis advisor Dr. David Bickford and a group of nature enthusiasts. This time, I knew where to find these frogs. We reached the stream and sure enough, there were plenty of Malabar Torrent Toads. This time, we also knew to record calls and Dr. Gururaja managed to get some sound recordings of these rare toads.
Adult male of G. ornata vocalizing. A small vocal sac is visible.
Source: Mandookavani. Ver. 1.0. 2015.
It has been 139 years since the toad was originally described. Yet, what we know is only incrementally more than what Gϋnther knew. The path to discovery is momentary and progress is excruciatingly slow. We now know the difference of the northern most point and the southernmost locality of where the toads occur are 300 km apart. We also know now, how the toads call. We have some inkling towards why the otherwise drab animal has bright colors on its underside. Several amphibians have such patterns and it has evolved to scare away predators. The toad, when threatened will jump and flip on its back, exposing the bright underbelly. Almost all vertebrates have evolved to stay away from bright colors. In Nature, bright means danger and this behavior of flipping on its back is known as ‘unken’ reflex.
‘Unken’ reflex by G. ornata
But we do not know if these colors serve some other purpose. Is it attractive to a mate? Or is there some other use to this coloration? We also have no idea where the toads breed or when. What is their breeding behavior? As for the larger question of why did this group of toads evolve to live in and around torrential streams? We simply don’t know!
Honey Valley, Coorg, enroute to Tadiandamol peak.
Frogs and toads evolved rapidly and adapted to various conditions in the environment. Right through the evolutionary history of over 300 million years, amphibians have evolved to be less dependent on water and perhaps it is one such driving force that molded the evolutionary trajectory of these fascinating torrent toads. The window of opportunity to bridge the knowledge gaps are wide open for everyone. The next time you are out there, keep an eye out for the dark frog and heed ear to the tinkling sound- for the frog may have something to say.
I thank Drs. Aravind, Gururaja and David for the several insights, and Abhisheka, Vinay, Thomas, Addy and Willike for the good company while out there in the field.