Minho river tidal freshwater wetlands: Threats to faunal biodiversity

Abstract

Tidal freshwater wetlands (TFWs) support a characteristic type of community and per-form fundamental environmental and ecological functions, however, studies conducted in this type of habitat are scarce and very fragmented. In the present paper, an overview of the TFW diversity and conservation state in the Minho River is provided, including temporal comparisons documenting indigenous fish and macrozoobenthos (principally mollusc) declines and information about the intro-duction of non-indigenous invasive species. We also discuss how this study can be exemplary of the actual ecological and conservational conditions of TFWs and the alarming present rates of indigenous biodiversity losses. Other TFW areas with comparable characteristics are probably under similar pressure and should therefore also be considered for conservation purposes. Better management of the flow regime, prohibition of construction near the margins, definition of more restricted areas for fishing, prohibition of some fisheries activities in defined periods of the year, enforcement of in-spection, an increase in education and information for fishermen and local populations, and restora-tion of degraded habitats are some practical measures that should be implemented to mitigate this situation. © Inter-Research 2008.