Searching for relations between manatee Trichechus manatus manatus calf strandings and environmental degradation in two Northeastern Brazil estuaries

Abstract

Northeast Brazilian populations of the Antillean manatee are threatened by different causes, where the frequent stranding of calves is possibly an indirect result of anthropic environmental degradation. In this study we surveyed the spatial-temporal stranding patterns of newborn manatee calves at the coast of the state of Rio Grande do Norte and identified potential abiotic and anthropic determinants. To do so, we investigated changes in the mangrove cover and extension of salt evaporation ponds and shrimp farms along two estuaries, Apodi-Mossoró and Piranhas-Açu, during 1998 - 2018. The incidence of strandings increased throughout the study period, especially in Apodi-Mossoró, suggesting that the growing salt and shrimp farming industries are significant contributors to the observed mangrove deforestation. Thus, our findings suggest a correlation between manatee calf stranding patterns and environmental degradation from salt and shrimp production in two Northeast Brazilian estuaries.