Ichthyofauna from natural flooded fields and adjacent estuary around the marine extractive reserve of Tracuateua, Amazonia: species richness and diversity.

In the present study, we investigated the diversity of fishes from naturally flooded fields along the Chapada community and the Quatipuru River estuary in the municipality of Tracuateua, Northeastern Pará, coastal Amazon. The samples were collected in two wetland collection sites and in one collection site of the estuarine region of the Quatipuru River from September 2019 to September 2020, one collection per month, thus comprising both dry and rainy seasons. A total of 1,293 individuals were collected, divided into 15 orders, 26 families and 49 species. The most abundant orders were Characiformes (31.4%), Siluriformes (29%) and Acanthuriformes (14.7%). The highest density of individuals was recorded during the rainy season (N=662), while the highest number of species was observed in the estuarine region (collection site 3) (S=32). The highest Shannon index diversity values were obtained during the dry season in collection site 3 (H'=2.3006). On the other hand, the richness was higher at this collection site during the rainy season (d=3.5794). This work provided the first detailed data about the local ichthyofauna, being useful to the further development of effective policies for the management and monitoring of regional natural resources.