Characterization of fisheries resources in water reservoirs of the solar saltworks in Ungawa Bay, Kenya

Abstract

The reservoirs of the salt works in Magarini Constituency within Ungwana Bay, Kenya support livelihoods of local fishers and fish traders in the area. However, despite this importance, information about their fisheries resources remains undocumented. This study aimed at bridging this data gap by characterizing aspects of these fisheries including fishing gear and methods, production (total catch, catch composition and catch rates) and the socio-economic importance. The study was conducted between January and June 2015 at Gongoni, Marereni and Kurawa landing sites in the Ungwana bay. Prawn seines and fishing traps were the main fishing gear used in the reservoirs. A total catch of 2,285.3 kg was recorded during the study period, with crustaceans dominating the catch in both seasons and at all landing sites. In total, 57 species belonging to 37 families were sampled comprising of 9 crustacean and 48 finfish species. The crustacean Metapeneaus monoceros was the most abundant in Gongoni and Marereni during NEM season while Oreochromis mossambicus was the most abundant finfish in Kurawa. Analysis of Similarity (ANOSIM) test showed a significant difference in catch composition between gear types with landing sites combination (R = 0.854; P = 0.010) but not between seasons (R = -0.125; P = 0.800). High species diversity was recorded for prawn seine fishing gear in Marereni during SEM season while the lowest diversity in the same season· was recorded for traps in Kurawa. There was significant difference in catch-per-unit-effort (CPUE) between fishing gears (df= 1; f= 16.979; p=0.0001) but not between seasons (df = 1; f,= 0.110; p = 0.741). Majority of the fishers and traders had no other income generating activities indicating a high dependency on the reservoir resources. This was associated with low education levels and hence inadequate formal skills to engage in other income generating activities. Results on post-harvest aspects showed that, a combination of boiling in salted water and sun drying was the most used method of preservation. The traders regarded this method as affordable with products having a maximum shelf-life of three months. The study revealed that fisheries production in the reservoirs is not affected by seasonality but rather influenced by factors such as the location of the reservoirs, characteristics of the gear used besides the daily operations of the salt works. This study has provided baseline data on the fishery in the salt works reservoirs, however longer term studies are required to generate more information necessary for formulation of sustainable management recommendations for these resources.