The Wildlife Institute of India (WII) has recently carried out a survey of the Ganga River, excluding its tributaries. The study revealed that 49% of the river boasts high biodiversity. This substantial level of biodiversity, including sightings of Gangetic Dolphins and Otters, points to reduced pollution levels and an overall healthier river condition.
The Study
Initiated by the WII on behalf of the National Mission for Clean Ganga, this comprehensive study is a flagship project of the Ministry of Jalshakti. It marks the first time that any survey has been conducted across the entire river, focusing on all elements of its biodiversity.
High Biodiversity Areas of Ganga
The study found that about 10% of the areas with high biodiversity lie along national parks and sanctuaries such as Rajaji National Park in Uttarakhand, the Hastinapur Wildlife Sanctuary in Uttar Pradesh, and the Vikramshila Gangetic Dolphin Sanctuary in Bihar.
Methodology Used
To assess and track biodiversity, the institute focused on key aquatic and semi-aquatic species such as the Gangetic Dolphins, gharials, otters, turtles, and various water bird species.
Findings
The survey revealed that many species previously absent from the main stem of the river are now returning. Notably, nesting colonies of the Indian Skimmer were discovered, Seibold’s water snake, considered extinct for 80 years, has been spotted again. Moreover, new distributions of puffer fish were identified. Numerous other species are migrating back from tributaries to the main stem of the river, signaling improved water quality and increased biodiversity.
Past Challenges: Loss of Aquatic Species
The Ganga had experienced significant reductions in the distribution and density of essential aquatic species due to loss of suitable habitat conditions, changes in the river’s morphology due to dam and barrage construction, bank alteration, agriculture, and sand mining. In the early 19th century, an estimated 10,000 Gangetic Dolphins were present, decreasing to 3,526 by early 2000. They disappeared entirely in Haridwar and most of the Yamuna and became extinct in smaller tributaries.
Threats to Freshwater Biodiversity
Although they only account for 0.01% of the Earth’s surface water, freshwater ecosystems support 10% of its species. According to the UNEP-WCMC, the loss of freshwater species diversity is higher than in marine and terrestrial environments, with 20% of all known freshwater fish under threat. The highest loss of freshwater biodiversity has been reported to be from the Indian subcontinent, particularly the Gangetic plains.
Government Initiatives on River Ganga
Several initiatives have been undertaken by the Indian government to restore the Ganga. These include the Ganga Action Plan, the National River Ganga Basin Authority, the Clean Ganga Fund, the Bhuvan-Ganga Web App, and the ban on waste disposal in the Ganga by the National Green Tribunal (NGT).
Way Forward
Efforts made by the Indian government to save the biodiversity of the Ganga align with sustainable development goal no. 15: protect, restore, and promote sustainable use of terrestrial ecosystems. As a result, water quality has improved and biodiversity has increased. However, it’s essential for future development approaches to recognize the importance of nature protection for our well-being.