The next 20 years saw him make several more trips to the river and snag a couple of hundred more such fish. “Every single one I caught back then had orange-coloured fins. That was the only sort of mahseer we could find in the Cauvery back then,” he says.

Not anymore, claims a recent study by Adrian C. Pinder (Bournemouth University, Dorset) and Rajeev Raghavan (St. Albert’s College, Kochi) of the Mahseer Trust, an international non-profit organization set up to protect the fish and the habitat it lives in.

“Prior to 1993, all fish recorded by anglers (from available photos) were orange-finned humpbacks. A book written by Henry Sullivan Thomas in the late 1800s also talks of a mahseer in the Cauvery with orange fins. However, when I visited the Cauvery in 2010, most of the fish I saw were the smaller blue-finned mahseer,” says Pinder in an email.

According to the study, which was conducted using data collected at Galibore, the number of orange-finned humpbacks in the wild is so low that the fish may be extinct in a generation.

Can this fish, considered to be a “superb fighter” and a “prize catch” among anglers, be saved?

The mahseer, a type of carp, is a hugely popular game fish, endemic to the rain-fed rivers of Asia. Around 45 species of the fish are believed to exist currently, 17 of which are in India.

Identified by Scottish physician Francis Buchanan Hamilton in 1822, references to the fish have been made in several books and records of the 19th century and it has been favourably compared to other notable game fish, including the salmon, the tarpon (this by none other than Rudyard Kipling) and the trout.

A fierce fighter

With its large head, distinct fold of flesh below the lower lip, bright scales and vari-coloured fins, the mahseer is an attractive fish. It is also a fierce fighter—anglers who have wrestled with it talk about broken rods and snapped lines. And like Santiago in Ernest Hemingway’s The Old Man and the Sea, they are willing to brave the most trying of circumstances to catch the big fish.

“I once jumped into 60ft deep rapids holding onto my rod with a mahseer at the other end,” says Mulley. “Else, he would have broken me.”

He isn’t the only one who has risked limb (and life) for the fish.

“I was fishing all alone at midnight, it was a good session, the mahseer were biting and I had caught around six so I didn’t want to leave,” says Derek D’Souza, another angler. “Then I heard a strange sound. I turned around and switched on the light. And found myself looking directly at a crocodile with its mouth wide open.”

He beat a hasty retreat after that. “Anyway, the fish don’t come if there is a crocodile around,” he adds.

Hunter-naturalist Jim Corbett, in his book Man-Eaters of Kumaon, refers to the mahseer as “the fish of my dreams”, and says that “angling for mahseer might well be described as a sport fit for a king”.

The British Raj felt that way too, says Sandeep Chakrabarti of the Wildlife Association of South India (WASI).

“Fishing was extremely popular pre-Independence in the Cauvery and along its tributaries. Before the Kabini dam was built, all these areas were very heavily forested and access highly restricted. Only the brave would venture into these areas to catch fish,” he says.

After Independence, however, fishing as a sport faded. “The locals in the vicinity would mostly catch fish for the table,” adds Chakrabarti. “Angling for the sheer joy of it is not really close to the Indian heart.”

N.R. Ramakrishna, joint director of fisheries in Karnataka, says the population of the fish has dwindled over the years since Independence. “Natural breeding and propagation took place back then. However, soon, due to water pollution, sand mining, dynamiting and construction, the breeding ground was destroyed,” he says.

Setting things right

When the Wildlife Protection Act was passed in 1972, a group of sporting fishermen set up WASI, says Chakrabarti. “They took a stretch of the Cauvery river from the forest department and started a conservation programme for the mahseer. Members of the association would go and fish, taking a valid licence and paying for it.”

Subsequently, this movement spread to the upper reaches of the Cauvery and the Coorg Wildlife Society was started.

“It was a good conservation measure,” says Ramakrishna. “Revenue collected from angling helped protect the stretch and there were campaigns against dynamiting and sand mining. Also, a lot of the locals in the area were educated and given employment, so poaching and illegal fishing decreased.”

The 1980s saw the rise of jungle lodges and resorts—eco-tourism that promoted angling tourism.

“Angling took place on a catch-and-release basis which is generally acceptable and this attracted tourists from all over the world. A lot of the former poachers, who are highly knowledgeable about the river, were employed as gillis, a sort of fishing guide,” says Chakrabarti, who sees a direct link between conservation and angling.

“Fishing employs local people and having people along the river offered the fish protection,” says A.J.T. Johnsingh, a vertebrate ecologist and keen angler himself.

It was also around that time that Tata Power decided to do its bit to support the rehabilitation of the species.

“We began breeding the fish artificially in the early 1970s at our centre in Lonavala,” Anil Sardana, managing director of Tata Power Co. Ltd, said in an email. “After carrying out thorough research and careful observation of the fish in its natural habitat, we transported healthy mahseer to our facility and reared it there for three years until they reached maturity and were ready to breed.”

The mahseer is a difficult fish to breed in captivity; the slow-breeding fish is very sensitive to its environment. After carrying out several experiments, experts at the hatchery decided that there were two species that could be bred in captivity—the blue-finned Deccan Mahseer (Tor khudree) and the Golden Mahseer (Tor putitora).

While the Golden Mahseer is found in the colder waters of the Himalayan foothills, the blue-finned Deccan Mahseer was introduced into the Cauvery.

“With this initiative, the company has embarked on a strong journey to safeguard and conserve our biodiversity, and work towards protecting our environment at large,” said Sardana.

“We used the fingerlings from Lonavala to create our own brood stock and have set up a hatchery in Harangi (Coorg),” says Ramakrishna, “The khudree is no longer an endangered species.”

A puzzling find

Pinder will never forget the sight of his first mahseer. He was all of eight when his eyes landed on a photograph of a European standing in chest-deep water holding a huge fish. Twenty-five years later, he managed to find his way to the banks of the Cauvery, where the photograph was believed to have been taken.

However, to his disappointment, the legendary fish he had crossed over 10,000km for appeared to be in short supply, “When I started visiting the Cauvery in 2010, one humpback was being caught a week. Most of the fish that we caught was the blue-finned Tor khudree,” he says.

The Cauvery is now teeming with Tor khudree, the Deccan Mahseer, a smaller fish with distinct blue fins.

“We always thought that Karnataka has only Tor khudree. None of us has seen a humpback here. However, these scientists are saying that the original fish of the Cauvery was the humpback and that it is now on the verge of extinction. We need to do a systematic full-fledged research to determine which one was the original inhabitant of the river,” says Ramakrishna.

Steve Lockett, also of the Mahseer Trust, says, “One of the big problems faced by us and every scientist that has worked on the mahseer is that of incomplete knowledge. Nobody so far has done any kind of intensive, long-term study and then cross-referenced against other studies. Sadly, the time for doing such work may soon be over and the largest mahseer in the world could slip away before we know exactly what it is.”

The elusive nature of the fish and insufficient documentation about it is compounded by another problem—right now, the fish has no scientific name.

“It used to be referred to by Tor mussullah and the use of the name has been perpetuated by anglers and scientists copying from early natural history and angling books written during British occupation. However, the fish that was described as Barbus or Hypselobarbus mussullah was originally described to be an inhabitant of the Krishna river, where our humpback mahseer has never been recorded,” says Pinder.

As a result, the term mussullah has been allocated to another species and the humpback mahseer now has no name. This has some alarming consequences, according to Rajeev Raghavan, coordinator, IUCN SSC Freshwater Fish Red List Authority.

“For a fish species to be assessed for its conservation status by IUCN, it has to have a clear taxonomic identity (scientific name). For the humpback mahseer, we still do not have one. So, unless we clear the identity and species status, and give the fish a scientific name, there is very little we can do to develop conservation plans,” he says.

The only way to establish identity at this stage is to conduct genetic testing and permissions are still being sought for it. “Science is available and genetic sampling is a very easy way of establishing the species. Once we do, we can see if it really is a threatened species and if so we can put it in the IUCN Red List,” says Chakrabarti.

A conservation plan certainly is the need of the hour—the study undertaken by Raghavan and Pinder found that there has been a steady decrease in the number of the orange-finned fish and an increase in the blue-finned one, “In 1998, the ratio of humpback to blue finned mahseer was 1:4. By 2012, this had dropped to 1:218,” says Pinder.

A relatively recent ban on angling in the protected areas of the forest, imposed due to a reinterpretation of the Wildlife Protection Act, hasn’t helped the situation, as there is now no way of tracking the performance of the remaining population. And that is a real pity as, according to Raghavan, “once the taxonomic identity is cleared, and the fish gets a scientific name, it will qualify to be listed as a ‘critically endangered’ species on the IUCN Red List, making it the rarest and most threatened mahseer species in the world”.

Poachers, pollution and loss of habitat are common enough reasons for species degradation. So is the introduction of an invasive species. For instance, the American grey squirrel is believed to be responsible for the dwindling of the British Red, the cane toad became a bigger pest than the ones it was supposed to destroy, the European rabbit wreaked absolute havoc when it was brought to Australia.

The blue-finned mahseer could have affected the indigenous humpback in a similar way.

“We could have caused an imbalance in the ecosystem when we introduced the artificially reared blue-finned mahseer to it,” believes Chakrabarti.

Pinder agrees. “Tor khudree was never native to the Cauvery and since being stocked has become invasive, wiping out the giant humpback,” he says.

Adds Johnsingh: “No one can be blamed for it, we just didn’t know. The hatchery in Lonavala was started with extremely good intentions, the company gave the fish when asked and it was introduced in the river. Twenty years ago, no one thought about its consequences.”

Today, however, since people are thinking about it, something needs to be done, says Pinder. “The current status of mahseer populations, their taxonomy, species distributions, ecological requirements and environmental stresses need to be investigated thoroughly,” he says.

After all, as Chakrabarti says, “This is a legendary fish that can go up to 100 pounds (about 45kg)—if the fish gets extinct without even a name, it would be a pity. How can we watch a species disappear before our own eyes?”

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