Ichthyofauna of Seridó/Borborema: a semi-arid region of Brazil

Abstract

Abstract:The Seridó /Borborema region is located between the States Paraíba and Rio Grande do Norte and a priority area for conservation of the Caatinga. This region is under the hydrological influence of the middle portion of Piranhas-Açu River basin. Previous systematic inventories of the ichthyofauna of this Caatinga's area are not significant. The Caatinga fish fauna is threatened due the advancement of historic anthropogenic activities, mainly agricultural. Furthermore, another relevant aspect is the recent governmental decision of transferring water from Sã o Francisco River to other Northern river basins, which includes the Piranhas-Açu basin. This study performed a systematic survey of the Seridó / Borborema's ichthyofauna. The sites were sampled during the years 2006 and 2007 (four annual, diurnal samples), using three different types of gear: beach seine nets, cast net and gillnets. We captured 13,009 individuals of 5 orders, 14 families, 28 genera and 35 species of fish. The predominant orders were Characiformes (21 species), Siluriformes (6) and Perciformes (5). The greatest number of species (11) was catch from the family Characidae, followed by Cichlidae (5) and Loricariidae (4). This inventory produced a comprehensive sampling of the middle portion of Piranhas-Açu River basin and its result overcomes the diversity reported in previous studies (22 species) on the same region. Keywords: Inventory, Fish, Piranhas-Açu River, Caatinga, Northeastern Brazil.Resumo: A regiã o Seridó /Borborema, localizada entre os Estados da Paraíba e do Rio Grande do Norte, é uma á rea prioritá ria para conservaçã o da Caatinga e encontra-se sob domínio hidroló gico da porção média da bacia do rio Piranhas-Açu. Levantamentos sistemá ticos sobre a ictiofauna desta região da Caatinga realizados até esse momento sã o pouco expressivos. A ictiofauna da Caatinga sofre ameaças devido ao avanço histó rico de atividades antró picas, principalmente agropastoris. Além disso, outro aspecto que merece destaque é a recente implantaçã o da obra de integraçã o do rio Sã o Francisco com as bacias hidrográ ficas do Nordeste Setentrional. O presente estudo realizou um levantamento sistemá tico da ictiofauna da regiã o Seridó /Borborema. As amostragens foram realizadas entre os anos de 2006 e 2007 (quatro amostragens anuais diurnas), utilizando redes de arrasto, tarrafa e redes de emalhar. Foram capturados 13.009 indivíduos pertencentes a 5 ordens, 14 famílias, 28 gêneros e 35 espécies de peixes. As ordens predominantes foram Characiformes (21 espécies), Siluriformes (6) e Perciformes (5). Characidae foi a família com o maior nú mero de espécies (11), seguida por Cichlidae (5) e Loricariidae (4). Este inventá rio produziu uma abrangente amostragem da porção média do rio Piranhas-Açu e seu resultado supera a diversidade registrada em estudos prévios (22 espécies) da mesma região. Palavras-chave: Inventário, Peixe, Rio Piranhas-Açu, Caatinga, Nordeste Brasileiro.

Ichthyofauna of Mundaú river basin, Ceará State, Northeastern Brazil

“…The predominance of the orders Characiformes and Siluriformes in the freshwater ichthyofauna of Mundaú river basin follows the pattern found among freshwater fishes in Brazilian Northeast (Ramos et al 2005, Nascimento et al 2014, Silva et al 2014, in Brazil (Buckup et al 2007), and in Neotropical region (Reis et al 2003, Lévêque et al 2008. 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.…”

“…Together with Poecilia vivipara, Serrapinus heterodon, S. piaba, and Steindachnerina notonota, they represented the most common species and could exhibit small sized body, generalist ecophysiological habits, and partitioned or all year reproduction. These features, likewise others related to anthropic disturbances, such hypoxia and eutrophic habitats, are usually present in the most frequent and abundant species in freshwater community studies in MNCE (Sánchez-Botero et al 2014, Silva et al 2014). However, most of the species were restricted to a few habitats, reflecting narrow ecological conditions for their occurrence.…”

Composition of the ichthyofauna in Brazilian semiarid reservoirs

“…Gurgel-Lourenço et al (2013) Reis et al 2003), as well as in Brazil (Buckup et al 2007). 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.…”

“…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).…”

“…However, in recent decades the number of research articles related to the ichthyofauna diversity of Brazilian semi-arid region has increased (Ramos et al 2005, Novaes et al 2013, Gurgel-Lourenço et al 2013, Silva et al 2014, Silva et al 2015, Gurgel-Lourenço et al 2015.…”