Wildlife & Biodiversity

Carnivorous alligator gar, the latest threat for Srinagar’s idyllic Dal Lake?

Scientists fear the presence of the non-native fish will harm the fragile flora and fauna of Dal Lake

By Irfan Amin Malik
Published: Friday 16 June 2023
One single alligator gar, however, can not do any significant damage to Dal Lake, says expert. Photo: Irfan Amin Malik

On May 11, 2023, a non-native alligator gar fish, known for its crocodile-like head and razor-sharp teeth, was found in one of Kashmir’s idyllic lakes, raising apprehensions about its impact on the native fish species.

The rare, carnivorous fish was caught by the Jammu and Kashmir Lake Conservation and Management Authority (LCMA) during the routine deweeding process near Sher-e-Kashmir International Convention Centre (SKICC), the main venue for the Group of Twenty (G20) tourism meeting in Srinagar, the summer capital of Jammu and Kashmir.

The alligator gar is a close relative of the bowfin species. It is a ray-finned euryhaline fish and is one of the biggest freshwater fish in North America and the largest species in the ‘gar’ family.

The finding sent alarm bells ringing among the scientists; they fear that the presence of non-native fish species will spell doom for the eco-fragile flora and fauna of the waterbody.

The presence of the carnivorous fish in the lake has surprised not just residents but also the scientists and authorities, who are now trying to ascertain its effects on the ecology of Dal Lake, the second-largest and the most famous lake of J&K.

Archana Sinha, principal scientist at Central Inland Fisheries Research Institute Barrackpore, Kolkata said alligator gar fish is not an Indian species and normally found in northern and central America and also in Mexico. “But in recent years it was also found in some parts of India like Bhopal, Kerala and from the waterbodies of Maharashtra and Kolkata.”

“Being a predator fish and a carnivore, it can eat all types of fishes and therefore poses a threat to native species and to the overall ecosystem. For example, gar fish grows rapidly and has a life span of 20-30 years. It would kill all fingerlings of fish species already present in the waterbody and has a tendency to destroy natural aquatic life of Dal Lake,” said Sinha. 

It is too early to determine the actual reasons of how alligator gar fish was found in Dal, Masood Ahmad Khan, an official from Research and Monitoring Section J&K Lake Conservation & Management Authority (LCMA), told this reporter. “But we have taken up the matter with the concerned fisheries department and the fisheries division of Sher-e-Kashmir University of Agricultural Sciences and Technology (SKUAST) to conduct an investigation and comprehensive studies to ascertain how and why the exotic fish reached the waterbody.”

Khan, who works as an executive engineer at LCMA, added that a total 12 native fish species are found in Dal and any exotic species can be dangerous to the indigenous fish species.

Dal, along with the adjoining Nigeen lake, is a major source of fresh fish consumed by the people of Kashmir and outside.

The “crocodile type fish” have caused a lot of panic among the fishing community whose livelihoods have depended on the waterbody for decades, said 24-year-old boatman Imran Ahmad Mir. “No one is even touching the water fearing an attack from the gar fish.”

Dal has already suffered extensively over the past four decades due to increasing encroachment, human interference and pollution.

The lake, which is linked to the livelihood of thousands, has witnessed extreme loss in water quality, mainly because of anthropogenic pressures such as discharge of untreated sewage. Dal Lake has already shown the impacts of warming temperatures, variation in hydrological regime, excessive nutrient load and invasion of non-native species, a 2022 study by the scientists of SKUAST Kashmir showed.

Read more: ‘Alligator Gar discovery a signal to revise list of fish introduced to India’

Alligator gars feed on other fish and are thrown in Indian waterbodies knowingly or unknowingly, said Sinha. “Gar fishes are euryhaline and can grow up to eight feet. They can be dangerous for indigenous fish species. During winter, they can even sustain in the cold waters of Dal because the temperature they mostly live in is 11-23 degrees Celsius.”

Such types of fishes are imported into the country to be reared in aquariums, she added. But when the fish starts growing in size and kills other fish, aquarium hobbyists often release them in the local water bodies, putting the local biodiversity at stake, the scientist noted.

“You may see gar fishes in Indian states where aquarium trade is thriving. For example, in Kolkata's Galiff Street pet market, more than 100 exotic species including gar fish are openly sold on Sundays. The Government of India has only allowed 92 species which can be imported and the gar fish is not included in that list, ” she adds.

The Indian Biological Diversity Act 2002 prohibits the presence of any kind of invasive fish species that can be hazardous to natural fish fauna, Khan said. “We are checking the CCTV footage and also investigating how the gar fish was found in Dal. Any violator found throwing the non-native fish in Dal will face action under Indian Biological Diversity Act 2002.”

One single alligator gar, however, can not do any significant damage to Dal, Irfan Khan, head of the Department Fish Genetics and Biotechnology, SKUAST Kashmir, told this reporter.

“Alligator gars are undoubtedly a serious threat to local biodiversity but only if they become adaptive in a particular environment,” he said. 

Two weeks after gar fish was found in Dal, a sudden death of a large number of fish in Dal Lake following heavy spells of rain last month triggered panic among locals even as experts.

However, LCMA's Khan rules out the gar fish as a reason for the death of native fish species. “The death of some fish species was likely caused by thermal stratification. There has been a fluctuation in temperature due to which many fishes have died in the past also.” 

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