Union environment minister Prakash Javadekar and Union water resources minister Uma Bharti have been entrusted with the task of cleaning the Ganga. While contemporary writings on the Ganga have focused largely on pollution, its role as a riverine ecosystem that supports rich biodiversity — 40 species of zooplanktons, 50 species of insects, 12 species of turtles and two mammals have been recorded — has largely been ignored. And as the river faces a crisis of existence, these creatures also face similar challenges. Naturalist Francis Hamilton was among the first to list over 275 species of fish in the Ganga in 1822. Since then, no comprehensive survey has been conducted along the entire river.
In the Himalayas, the river supports over 50 species of fish that are today rare or endangered. A recent study in the Garhwal Himalayas reports a rapid decline in fish diversity due to landslides and soil erosion. In 2011, the environment ministry noted the dumping of silt in the river by hydropower companies. The freshwater aquatic biodiversity of the Ganga depends on a number of variables from nutrient content to amplitude of flows, to turbidity of the water in motion. High turbidity, for instance, leads to the choking of gills leading to increased mortality of fish. Yet none of these factors are considered in river conservation programmes.
On the Alaknanda over 24 dams are in various stages of development. A study by the Wildlife Institute of India has highlighted that 35 mammals, 350 birds and 1,000 plants along with species such as the snow leopard and the brown bear will be impacted once the forests are submerged for hydro-projects. At Devprayag, the confluence of the Bhagirathi and the Alaknanda, an already shrinking population of smooth coated otters will be impacted by an upcoming dam.
In the plains, the Ganga was once home to ghariyals and dolphins: Today, the former are predominantly in the Chambal River. The dolphins remain confined to small pockets of Uttar Pradesh and Bihar, unable to migrate as the fish ladders built on the barrages are too small for them or have never been opened. Assessing the condition of these ladders should be a part of the environment clearance process.
In Varanasi, few may have visited the turtle-breeding centre that was once set up to clean the river but not many studies have been undertaken to find out if the release of these flesh-eating turtles have helped clean the river. Species like the Indian soft shell turtles are sold for their meat — others like the three-striped roof turtle are endangered.
In our zest to clean the Ganga, one hopes that the two ministers turn their attention to these creatures that do not have a vote but can shape the Ganga as much as her devout followers.
Bahar Dutt is a conservation biologist and author of Green Wars — Dispatches from a Vanishing World
The views expressed by the author are personal