Analysis of Optimal Harvest and Management of Capture Fishery of Lake Ziway, Central Ethiopia

Abstract Even if there is fluctuation in fish species diversity and relative abundance of the species, Lake Ziway provides numerous environmental and/or ecosystem services. Despite to its importance, the Lake faces numerous threats because of its public good characteristics. Following the exponentially increased demand for fishes and the resource being public good, magnificent number of individuals are participated in capture fisheries in order to secure their livelihood. Free access to the fisheries, illegal fishing gears and environmental degradation are among the main reasons of decline in fish species and degradation of the Lake. From the current stock assessment survey, the study showed decline in biomass of fish over time. These negative trends in the Lake Ziway fisheries and poor water quality led to loss of livelihoods of many households who are directly or indirectly dependent on the Lake. Therefore, management of Lake Ziway fishery becomes very essential to manage the resource efficiently in a way that maximize fishers present and future benefits otherwise, the fish resource will disappear in the near future. Concerning management practices, most of the fishery regulations in this Lake put emphasis on the restriction of fishing gear, but the application of this instrument with its restrictions is almost zero. Moreover, Individual Transferable Quotas (ITQs) foster greater transparency and accountability for the management and enhancement of fishery resources by quota owners. In this regard, since it generates a sense of ownership and its versatility in providing a stable and productive market, ITQs are more effective than gear restrictions and in fact, it has major social benefits by controlling overharvesting. Due to this, to ensure the nutritional and food security of the country currently and in the near future, there is a need to enforce fishing gear restriction and set ITQs. Furthermore, there must be strong effort on studying the current stock of fish, and numbers of legal and illegal fishers to set Individual Transferable Quotas (ITQs) and Total Allowable Catch (TAC) for sustainable fishery management of Lake Ziway.