RIVER CONNECTIVITY AND EEL MIGRATIONS
Keywords:
Connectivity, migration, Anguillid eels.Abstract
Human land-use activities often affect the quality, quantity and habitat of freshwater ecosystem, which need to be carefully managed to ensure their integrity and provision of services is sustainable. In South Africa, legislation has established resource-directed measures to attain a sustainable balance between the use and protection of water resources. These procedures have been implemented in most of South
Africa’s nine water-management areas, resulting in new legislation to protect these resources. Unfortunately, very little protection has been afforded to river connectivity maintenance and fish migrations. Water storage and flow regulation for agriculture and other resource use activities, 610 formal dams and ,1430 gauging weirs have been constructed that act a partial or complete barriers to fish migration on river ecosystems. The Western Indian Ocean (WIO) Anguillid eels (Anguilla spp.) are long distance catadromous migratory fishes that use both marine and inland ecosystems to complete their life cycles. As they occupy both environments, these eels are particularly vulnerable to marine and freshwater derived threats, and act as ecological indicators of the ecological integrity of riverine, estuarine and oceanic environments. Globally, Anguillid eels have a high socio-economic value and are targeted for commercial and subsistence fisheries. They are proposed to have the highest economic value per weight of any fish. Anguillid eels satisfy a providing function in term of food but also in terms of recreational, cultural and spiritual values. Unfortunately, little is known to the contribution of eels to subsistence fisheries along the coast of the WIO region, and thereby the contribution of these migratory fishes to the livelihoods of vulnerable African human communities is left hanging. The aim of the study is to assist the migratory pathway of Anguillid eels throughout the WIO regions and discuss migration and connectivity stressors of these eels.
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