The newly built Ribb Reservoir fisheries, Tana Sub‐basin, Ethiopia: New fishery establishment, diversity, production, challenges and management

Abstract

AbstractIn the future, agriculture alone may not produce the food needed to feed the increasing world population. Hence, it can be augmented by developing irrigation and water resources, mainly fisheries resources. In Ethiopia, especially in the Tana Sub‐basin, the expanded irrigation practices by building dams and weirs along the tributaries of Lake Tana did not consider fisheries nor the development and management. The aim of this research was, therefore, to promote fisheries and integrate them into the irrigation systems of the Ribb Reservoir in Ethiopia. During the sampling time (from September 2020 to August 2021), primary and secondary data collection and discussions with experts and fishers were conducted. Although the dam prevented the upstream spawning migration of the Labeobarbus species, the reservoir created a new fisheries development. Water quality parameters, such as temperature (23.82 ± 1.38°C), pH (6.36 ± 0.64) and dissolved oxygen (8.84 ± 3.54 mgl‐1), were within the acceptable range for fish. Of the 11 identified fish species, L. nedgia and L. surkis were the most and the least common species, respectively. Riverine and cut spawner species were the sources of the population. However, Oreochromis niloticus (Nile tilapia) was restocked in 2017 to increase the livelihoods of fishers. The Fulton condition factor, K values of L. nedgia (1.63 ± 0.25), L. intermedius (1.70 ± 0.27), C. gariepinus (0.61 ± 0.13) and O. niloticus (1.65 ± 0.29), and their ‘b’ values were <3. The newly established fishery in the reservoir is the source of income for fishers, and its annual production has been shown to increase from 148.5 to 1034.1 tons/year, indicating fish are adapting to the reservoir. However, the fishery has faced many challenges, such as illegal fishing, fisher engagement, and fishing gears. Limiting the number of fishers, restrictions on fishing gears and seasonality of fishing are some of the mitigations.