Climate change and variability effects on inland fisheries: Lake Kariba, Zimbabwe.

Abstract

African inland freshwater fisheries support the livelihoods of more than 12,3 million people, and fish is the main or only source of animal protein for approximately 200 million people or 20% of the African population. Several studies indicate that fish productivity and catch in freshwater ecosystems in Africa are declining because of stressors such as overfishing, pollution, illegal fishing, bad management, and climate change. Several researchers concur that climate change is one of the most significant stressor threatening fisheries as it interacts with and amplifies existing stressors. Fish resources are climate-sensitive, therefore, changes in climatic conditions, particularly temperature and rainfall, alter the fish's chemical and physiological processes, consequently affecting the livelihoods and food security of fishery-dependent communities. Several empirical studies have been conducted to demonstrate the impacts of climate change and variability on fish production in African inland freshwater fisheries, including Lake Kariba, Zimbabwe. However, there is a paucity of information on the impacts of climate change and variability on fishery-dependent communities on the shoreline of Lake Kariba in Zimbabwe. To address the knowledge gap, this study investigated the effects of climate change on inland freshwater fisheries in two major fishing districts found along the shoreline of Lake Kariba namely Binga and Kariba/Nyaminyami Rural Districts in Zimbabwe. The study assessed the vulnerability of small-scale fishers and fishery resources to the effects of climate change and the fisher’s perceptions of climate change. In addition, the fisher’s adaptation strategies and the barriers and limits to adaptation were identified. Lastly, the study recommended strategies that can be adopted to build the resilience of freshwater fisheries to the probable effects of climate change. The study employed a mixed-method research approach to collect data. Primary data were collected from small-scale fishers and key informants using a semi-structured questionnaire and focus group discussions, and secondary data of climate variables were obtained from the Meteorological Services Department of Zimbabwe. The data were subjected to different statistical analyses using IBM SPSS Statistics 27 and Microsoft Excel.Study findings indicate that small-scale fishers of Lake Kariba are aware of the climate change phenomenon. Most fishers indicated that the temperatures have increased (83.8%), rainfall decreased (73.6%) and the occurrence of extreme weather events such as droughts (56.9%) and floods (63.1%), has also

increased in their respective areas. Fishers believe that the changing climatic conditions have adversely affected fish productivity and their fish catches, resulting in fishers employing several strategies to adapt to the changing environment and declining fish catches. These strategies include, but are not limited to, changing fishing gear, targeting new species, increasing fishing effort and days, adopting alternative livelihood strategies and migrating to a different fishing camp or village. A multinomial logistic regression model indicated that the fisher’s experience positively and significantly influenced the adoption of all adaptation strategies except livelihood diversification. The Livelihood Vulnerability Index (LVI) shows that fishing communities in the Kariba district are more vulnerable to the impacts of climate change than those in the Binga district, due to their lower adaptive capacity and marginalisation of fishing communities in the Kariba district. High dependency on climate-sensitive resources as the main livelihoods increased the sensitivity of the fishing communities to the impacts of climate change. Findings indicated that the fisher’s ability to adapt to a changing environment and declining fisher resources was hindered by several factors such as fishing regulations, a lack of access to basic services, and institutions, lack of technologies, ecological limits and natural limits. Therefore, to build or strengthen the resilience of the fisheries sector in Lake Kariba, fisheries managers, the government, agents of development, non-governmental organisations and the resource users should ensure effective lake co-management, increase fishers' access to early warning systems, ensure stakeholder participation in decision-making processes, education and raise awareness, provide aid and basic services, conduct fish stocks assessments and formulate pro-sustainable fisheries policies. This study contributed empirical evidence to current debates in the literature on the impacts of climate change on fishing communities, by enhancing an understanding of the characteristics and determinants of fishing communities’ vulnerability, adaptation strategy and limits and barriers to the adaptation of fishing communities to climate variability and change. The findings form the basis for further detailed research into the vulnerability and adaptation of small-scale fishing communities to climate variability and change. Collaborations between researchers, extension officers, development agencies, and fishers to formulate climate adaptation strategies to promote resilience in the fishery sector for sustainable fisheries for the future generation is encouraged.

Keywords: vulnerability, adaptation, resilience, small-scale fisheries, Lake Kariba.