The authorities have banned this fishing gear although we watched two groups of fishermen deploying their unmistakable blue nets in the river on the outskirts of Guwahati. Another common fishing technique kills dolphins directly.
These are gill nets, which are made of filaments so fine that dolphins can't detect them. Ganges River Dolphins have only vestigial eyes and are effectively blind. They primarily sense the world with echolocation. They fail to notice the gill nets and become entangled. Adults are usually powerful enough to escape. The new generation, the calves, however remain trapped and they drown.
The gill net is the single greatest killer of dolphins in the river. Ganges river dolphins are also deliberately hunted, despite being a protected species under Indian law. The poachers extract oil from the dolphin's body as the flesh starts to rot, and use it in a special kind of fishing bait.
The pungent oil has the dual function of binding scraps of poultry and fish waste into a solid lump of bait and being particularly attractive to a large species of catfish. The fish commands a good price at the markets. The dolphin oil bait is localised to a handful of communities in the Lower Brahmaputra. Aaranyak is trying to persuade them to halt the practice. The group's researcher Chandan Ri has worked in the villages, studying the tradition and talking to its or so practitioners about its illegality and impact on the dolphin population.
Chandan sometimes receives an angry reaction. But Chandan Ri told me that the usual response to his questioning is more positive. They confessed that they had done this dolphin hunting in the past and say they don't want to carry on doing it in the future. Aaranyak regards community engagement and involvement as an essential component of its conservation approach.
As well as conducting the dolphin count this year, the survey boat and crew undertook a dolphin "yatra", travelling km of the river to stage "dolphin dramas" and other educational events in waterside villages. In recent years, the organisation has also encouraged the establishment of a network of many community-based dolphin conservation groups throughout the river system. Local villagers, who include fishermen, regularly survey local dolphin numbers and deaths for Aaranyak.
They also educate their neighbours about the dolphins, their part in the ecosystem and about practises which are good and bad for the dolphins' survival. Aaranyak also works with these communities to explore ways of making a living from the river other than fishing.
This includes river dolphin ecotourism. According to Lucy Bodman-Whetham of ZSL: "The one very nice and unique thing about this project is that with the dolphin conservation network, which is community-based, we are putting the responsibility in the hands of the local communities in many different areas of the Brahmaputra river.
I think that's what's make the difference here. Some dangers to the dolphin lie out of the hands of riverside communities. Large river construction projects such as hydroelectric dams are planned for sections of the Brahmaputra. Conservation Issues Once present in tens of thousands of numbers, the Ganges river dolphin has dwindled abysmally to less than during the last century owing to direct killing, habitat fragmentation by dams and barrages and indiscriminate fishing.
It is for these reasons that despite high level of protection, its numbers continue to decline. The absence of a coordinated conservation plan, lack of awareness and continuing anthropogenic pressure, are posing incessant threats to the existing dolphin population. Education and awareness programmes for fishermen and other riparian population are conducted for communities along the rivers. A strategy and Action Plan for the Ganges river dolphin conservation has been formulated for Uttar Pradesh with the help of the State Forest Department.
A network of partners for the Ganges River Dolphin Conservation in the country is also created. Habitat and Distribution Ganges river dolphins prefer deep waters, in and around the confluence of rivers. Building a future in which humans live in harmony with nature. Use of river water for irrigation of agricultural fields to support the rapidly increasing human population has resulted in fragmented groups of dolphins that are now living in five sections of the Indus river system.
Currently, there are approximately individuals remaining with some subpopulations estimated to have only approximately 20 animals left Braulik a. The Ganges river dolphin faces many threats including fishing, industrial pollution, shipping, poaching, climate change, habitat fragmentation by barrages, flow regulation and depletion from hydropower generation and diversions for irrigation.
This subspecies is likely declining in numbers as well, with only estimated individuals remaining Smith et al The extinction of the baiji dolphin in the Yangtze River which was threatened by so many of the same issues as the Indus and Ganges river dolphins, clearly demonstrates how important conservation actions are to save species. Addressing the conservation issues facing the Indus and Ganges dolphins requires a large coordinated effort across the species range.
We are focussing on our strengths and will be providing targeted technical veterinary support to grassroots groups in India and Pakistan that are working to rescue river dolphins that are trapped in canals.
Indus dolphins in Sindh Province, Pakistan accidentally leave the river and become trapped in irrigation canals where they die unless they are rescued. Similarly in Uttar Pradesh in India, the same phenomenon occurs, where Ganges dolphins are reported in canals requiring rescue. In both countries, there are local teams working to locate and rescue trapped dolphins and return them to their river habitat. Sometimes as many as ten dolphins each year are rescued. This presents a valuable opportunity for biologists to gather important data on the health and reproductive status of this endangered species which so far is almost completely lacking.
We will be providing training and long-term technical support in veterinary skills, health assessment, and sample analysis to Indian and Pakistani researchers with the ultimate goal to provide important information that will improve the conservation of these populations. Your contribution will directly support the collaborative enhancement of existing local rescue efforts, specifically through the integration of technical veterinary and health assessment support, that will inform conservation actions to increase survivability of this species.
Lockyer, C.
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