Biodiversity and fisheries management opportunities in the Mekong River Basin."

Abstract

Due, in part, to extreme ecosystem complexity, relatively un-regulated tropical rivers support a high biodiversity, rivalling that of marine systems. Such rivers, the Mekong Basin being perhaps one of the greatest, traditionally support very important and under-valued fisheries. High diversity of resources, in close proximity to large human rural communities, leads to a high degree of participation in resource exploitation. In essentially agro-fishery livelihoods setting such as this, large commercial fisheries do occur, but part-time fisheries using smaller gears are, generally, the norm. The linkages between biodiversity and exploitation are immediately obvious. Reduced biodiversity will lead to decreased participation, shifts in fishing effort and generally unfavourable socio-economic impacts. Caution needs to be exercised when applying conclusions drawn from marine fisheries to river fisheries. Marine and river fisheries function differently in several notable respects. Some threats to biodiversity, including over-exploitation and the use of destructive gears, arise from within the fisheries sector. One solution involves a shift to co-management approaches, which are already widespread, and, in places, locally effective. The use of resource allocation systems (fishing lots), highly developed in the Mekong basin, enables the control of open access and is, potentially, a very important tool in biodiversity conservation, but requires more research before being promoted more widely. Aquaculture, certainly not a universal remedy for the problems of capture fisheries, involves its own set of biodiversity impacts. Chief among these are habitat losses and the widespread introduction of exotic species and strains. An effective solution for the problem of introduced of species is the development and application of codes of practice for pre-introduction assessments. The greatest threat to biodiversity arises from other sectors, where activities can promote extensive loss of habitat, ecosystem simplification and reduced water quality and quantity. The current socio-economic benefits arising from the river fishery provide the major economic and social argument for improving integrated natural resources management to address the problem of general ecosystem decay. Recently, this consideration is demonstrably influencing development policies. Overly negative attitudes toward the impacts of fisheries on biodiversity in rivers will undermine biodiversity conservation, especially in the Mekong.