High and Dry: The Cauvery’s Otters Need Their River Back

The Cauvery (or Kaveri) is more than a river. It’s a river whose history runs deep. For centuries the Cauvery was a source of folklore and tradition. For many of us who live in Bengaluru, it is our source of piped water. This river that quenches our thirst is also home to two, and possibly three species of otters — the small-clawed, smooth-coated, and Eurasian otter.

All three species of otters are protected under the Indian Wildlife Protection Act (1972). Given that most rivers in the country are heavily extracted and modified, otters face a number of threats. By far the most serious threats to otters are poaching for their pelt and habitat loss. The more sociable among the three, the smooth-coated otter, is locally extinct in many river basins owing to targeted poaching and hunting, with poachers employing trained dogs and jaw traps to kill them, and their pelts travelling as far as China and Vietnam to be fashioned into coats.

With its source in the Western Ghats around Coorg, and tumbling eastwards on an 800 km journey, the Cauvery of today barely makes it to the Bay of Bengal. I have journeyed the stretch of Cauvery flowing through the state of Karnataka, and have come away shell-shocked over how much abuse a river can take and still continue to sustain life. Barring the stretch of river flowing through the Cauvery Wildlife Sanctuary, the river is a deathly pale version of what it was before the riverside vegetation (riparian) was completely stripped to make way for agriculture, settlements, and other modifications. The beautiful, life-sustaining native vegetation that grows along the river not only provides a habitat to birds, otters, and other biodiversity, but also acts as a wall between agriculture and the river, filtering pollutants before they enter the water. All along the Cauvery, this has now been replaced by intensive agriculture, coffee plantations, sewage belching settlements and towns that add to the contamination.

This is the unfortunate story of the pollution of the Cauvery and most rivers in the country. Nothing changes the very nature of our rivers like intensive sand mining where sand is gouged out from banks and the riverbed. Sand mining is all-pervasive along the Cauvery, starting from near the source, all the way into the plains. When the sand from river banks is exhausted, the illegal mining moves on to the riverbed. The general public knows little about the role this ‘minor’ mineral plays in our lives and the life of a river.

When most of the sand is extracted, there is little percolation, and the river runs dry earlier in the season without the sponge-like sand holding water and releasing it slowly. Erosion of banks also increases with the sand gone. These are some effects on the river. The untold effects on otters and fishermen is another story.

Sand mining destroys otter habitat. It also destroys the habitat of numerous species of fish, crustaceans, and other invertebrates that both otters and people depend on. In the headwaters in Coorg, the small-clawed otter which is also the world’s smallest species of otter jostles for space with illegal sand miners who are active day and night. These otters are elusive in nature and mostly den in riverside vegetation and use sand banks as signalling posts, playgrounds, and to dry off after a swim. When the sand and riverside vegetation is cleared, and hunting is rampant these otters have no refuge they can escape to.

In the plains, the smooth-coated otter faces more serious threats. Industrial-scale sand mining with its own temporary townships and illegal economy, intensive and unsustainable gill-netting by fishermen, dynamite fishing, diversion of water to far away urban centres, dams, pollution from agriculture, and settlements all encroach, fragment, and chip away otter habitats. This scale of sand mining is a complex issue along the river because not only does it directly affect and impede the functioning of the river, but it also changes the nature of interaction between otters and fishermen further imperilling both.

Smooth-coated otters are primarily fish-eaters. They live in groups numbering up to 15. They are apex predators of the freshwater ecosystem they inhabit and hunt medium to large sized fish, the very resource also prized by fishermen casting out nets. The otters also depend on banks, bankside vegetation, and sandy islands to dig their dens. As fishing intensifies, otters end up at fishing nets trying to make an easy meal of the catch and in the process damaging nets. As the density of fishing nets along the river increases so does the risk of entanglement for otter pups, mugger crocodiles, turtles, and birds. Fishermen retaliate by destroying den sites, and in some cases, by killing them directly or aiding otter poachers.

Enter the sand mining overlord and life changes drastically for the original inhabitants of the river: otters, fishes, birds, and animals. With sand mining taking over traditional fishing stretches, conflict between fishermen and otters increases because fishermen are displaced into closer waters. Dynamite illegally sourced from quarries is used to kill fish in the most destructive form of fishing called blast fishing. Otters, crocs, and other freshwater fauna have to navigate a veritable minefield to survive in the river.

While the demand for otter pelt in southeast Asia and China drives otter poaching along Indian rivers, the demand for sand from Bengaluru and other towns and cities drives sand mining in the Cauvery. Imagine an entire city rising up, being built with sand from the Cauvery and water pumped miles way to be carelessly squandered away to wash cars and yards. Both these demands seriously threaten otters. Fishermen too are disproportionately affected by sand mining which excludes them from fishing and contributes to an already declining fish catch.

There is some respite from all of this though, and that is in the form of a 110-km protected stretch of the river in Cauvery Wildlife Sanctuary where all forms of human extraction are banned. There are no ugly settlements along the river here, no sand being mined, fish being blasted, crops being cultivated, or even fish being caught.

This river-scape truly belongs to the original inhabitants of the river — otters, crocs, turtles, birds, etc. The waters here are rich with mahseer that have disappeared elsewhere, and endangered soft-shell turtles and fish eagles. It is interesting to note that fish eagles are absent when there are no large riverside trees available for nesting and perching. The otters here hunt for fish without the fear of entanglement in nets, and muggers thrive. Water-dispersed and broad-canopied Arjuna trees define the course of the Cauvery, staying green throughout the year, while the surrounding hills turn parched brown in the summer months. It is astonishing what protection can actually do. Here, one can observe otters squaring off with mugger crocodiles like they have for eons. Life thrives in the sanctuary.

The sanctuary though only protects about one-eighth the course of the river. Otters are not restricted to this section alone, but studies have shown them to be incredibly resilient. They are found in large stretches of river that are not protected, river stretches that are completely exposed to the vagaries of human use. They are here because this is the only habitat available to them, and not because humans have learned to coexist peacefully with them. For an animal that was once common across most Indian rivers, this is one of their last strongholds.

While I’m ashamed to call the Cauvery a river in many sections that I know well, observing otters in the most unlikely of places gives me that glimmer of hope that the river might not be all lost after all. The animals must be credited for keeping the element of the river alive where even fishermen might have lost hope, where trees are all but history, and where dam walls have replaced rapids. It is this resilience that should lead to a call for action to restore the Cauvery to the river of yesteryears, something that we were all immensely proud of.