Deep in the rivers of the Himalayas many fish species of ecological and commercial importance exist, including several migratory species that move between the high mountains and the lowlands for spawning and feeding. However, knowledge of the biology of fish species from the Himalayan region is sparse and scattered across the six countries: Afghanistan, Bhutan, China, India, Nepal, Pakistan, due to geographic, political and economic challenges.
Fish experts from India, Nepal and Pakistan recently met in Kathmandu, with support from IFC and the Australian and Japanese government, to share information and experiences, and discuss options for sustainable management of fish species in rivers with hydropower. The Himalayan fish experts were joined by representatives from Nepali government agencies, NGOs, molecular biologists from Center for Molecular Dynamics Nepal (CMDN), researchers, USAID United States Agency for International Development (USAID) and its Paani project – a Nepal-based freshwater biodiversity protection project, to gain a better understanding of Himalayan fish biology.
“Managing the impacts of hydropower projects on fish requires a good understanding of each target fish species’ biology, including their reproductive cycle, migratory patterns, habitat requirements and dietary needs,” said Leeanne Alonso, IFC Biodiversity Specialist based in DC.
IFC and hydropower developers in Nepal and Pakistan are working together to better manage environmental and social impacts related to hydropower projects. Of particular interest are fish, many species of which are ecologically, commercially and culturally significant. One of the key unavoidable impacts of a hydropower project is disruption of migration pathways for migratory fish and alteration of aquatic ecosystems. The extent of impacts is different for each hydropower project and depends on the sensitivity and biological requirements of the aquatic organisms at the site.
Due to interest in sport fishing and a popular fish for eating, a considerable amount of research has been conducted on the Golden Mahaseer (Tor putitora). However, less information is available for other key species in the region, including other mahaseer species, several species of snow trout (Schizothorax richardsonii, S. plagiostoma, S. progastus, and others), Pakistani Labeo (Labeo dyocheilus), Suckerhead (Garra gotyla), and Indus Garua (Clupisoma garua). Even less is known about rare and endemic species with limited distributions, such as the Kashmir catfish (Glyptothorax kashmirensis) and Nalbant’s loach (Schistura nalbanti).
Similarly, participants demonstrated a concentrated interest on the Golden Mahaseer, particularly for hatcheries, but a lack of information on other fish species in the region. Researchers expressed concern for the decline in aquatic ecosystems and habitat for fish across the region due to a multitude of human impacts including pollution, water diversion, overfishing, sand mining and hydropower. Presentations on captive breeding of Mahaseer, particularly by Tata Power company in India, provided details on the biology and life cycle of this fish species and sparked a good discussion among participants. Hatcheries seem to be active and successful in all three countries, but sharing techniques would benefit all across the region.
Knowledge was exchanged on fish ladders in the region between Nepali scientists, offering their views on the need to improve fish ladders in Nepal. Few fish ladders are known to be working in Pakistan, likely due to the very high dams in most hydropower projects.
“Fish ladders are needed and feasible but more research is needed on fish biology and successful designs used in other parts of the world to build good fish ladders in the Himalayan region,” said Alonso.
Participants also discussed other knowledge gaps in small groups and captive breeding, stock assessment, fish biology and aquatic ecosystems.
“The region would benefit from more coordinated research, focusing on the conservation of Himalayan fish,” Alonso added. “This would help our understanding of the biology of fish species and their commercial importance, which is critical to sustainable management of their populations in the region.”
To learn more about IFC’s work to help advance sustainability in Nepal’s hydropower sector, visit: www.ifc.org/hydroadvisory