Fish fauna of Pratagi River coastal microbasin, extreme north Atlantic Forest, Rio Grande do Norte State, northeastern Brazil

Abstract

may represent areas of reproduction, protection and feeding for some marine species, including commercially important. The east coast of Rio Grande do Norte is composed by small and medium-sized basins partially or fully inserted in the Atlantic Forest, representing the northern extreme of this biome, with only 4.1% of the native vegetation (Fundação SOS Mata Atlântica and INPE 2012), composed by small isolated fragments. Therefore, the aim of this study was to inventory the ichthyofauna of the coastal Pratagi River basin, located on the east coast of the state, region with intense tourist activities, and report the main anthropogenic impacts on the basin, to increase the knowledge and support to conservation strategies for the Atlantic Forest fish fauna. Material and Methods Study site The study was conducted in Pratagi River basin, located in Ceará-Mirim Municipality, Rio Grande do Norte State. The main course of the Pratagi River has about 10 km long and is a tourist natural attraction of Rio Grande do Norte coast due to its high landscape value, with two popular sites mainly visited by tourists who make buggy rides in dune areas at the east coast, the Lavacu and Cachoeirinha Pitangui waterfall. The Pratagi River mouth is distant about 30 km from Natal, state capital city, and the main river course presents excerpts with clear waters fringed by dunes in Restinga and Atlantic Forest remnants until emptying into the Atlantic Ocean (Figure 1). Data collection Eleven samples were taken from five sites along Pratagi River basin, from the headwaters to the estuarine portion.

Ichthyofauna of Mundaú river basin, Ceará State, Northeastern Brazil

“…However, when estuarine and marine species are also considered, the order Perciformes is the most abundant, corroborating with other MNCE species listings (Soares-Filho et al 2010, Paiva et al 2014.…”

“…Gurgel-Lourenço et al 2013, Sánchez-Botero et al 2014). Few coastal basins in this hydrographical region were fully cataloged, for example Gramame river basin, in Paraíba State, in which (Gomes-Filho & Rosa 2001) there were recorded 23 species; Curimataú river basin in Paraíba and Rio Grande do Norte States, 22 species (Ramos et al 2005), and Pratagi river microbasin, also in Rio Grande do Norte State, 22 species (Paiva et al 2014).…”

“…MNCE is largely inserted in the Brazilian semiarid, an area of Caatinga's phytophysionomy where rivers are mostly intermittent resulting in a simple hydrographical network (Rosa et al 2003), except for headwaters and coastal areas in Alagoas, Pernambuco, Paraíba, and Rio Grande do Norte States, which are greatly nested within the Atlantic Forest (Rosa & Groth 2004, Paiva et al 2014. Therefore, these semiarid river systems are constantly being modified through their damming as an attempt to assure the inland population a hydric demand during long drought periods.…”

Composition of the ichthyofauna in Brazilian semiarid reservoirs

“…The proportional richness of the order Characiformes has been a natural tendency of ichthyofauna basins under influence of the Caatinga biome (Ramos et al 2005, Silva et al 2014, Silva et al 2015. The Characidae family, one of the richest families in this study, generally has the greatest richness in fish diversity in Northeast Brazil (Ramos et al 2005, Paiva et al 2014, Silva et al 2014, Silva et al 2015. Rosa et al (2003) observed that Characidae was the most diversified family (50 species) when studied the diversity of Caatinga ichthyofauna.…”

“…bimaculatus is a native species, is the third most abundant representative in the two reservoirs, along with other small Characidae species, popularly known as "piabas" in Northeastern Brazil, that is generally the most abundant group in the region (Ramos 2012, Paiva et al 2014, Silva et al 2014. These species are not valuable for fisheries purposes due to their relatively small size (Ramos 2012).…”