Comparação da eficiência relativa de dois apetrechos de coleta de peixes em praias no baixo rio Purus, Amazonas, Brasil

Abstract

Comparação da eficiência relativa de dois apetrechos de coleta de peixes em praias no baixo rio Purus, Amazonas, Brasil Cleber DUARTE¹, Cláudia Pereira de DEUS 2 , Lúcia RAPP PY-DANIEL 3 RESUMOApesar das praias serem consideradas um dos sete mais importantes habitats aquáticos da Amazônia, poucos trabalhos foram realizados quanto ao levantamento de sua ictiofauna, principalmente quando utilizados diferentes apetrechos de coleta. Este trabalho teve como objetivo comparar a eficiência relativa de dois apetrechos, rede de cerco e malhadeira, ambos utilizados de forma ativa (arrasto), em três praias localizadas no baixo rio Purus. A rede de cerco apresentou maior número de espécies e indivíduos capturados, no entanto, a malhadeira apresentou maiores valores de biomassa total, representada principalmente por Siluriformes. A baixa similaridade da fauna de peixes capturada (38%) foi devido à exclusividade de espécies coletadas com cada apetrecho, 41 com rede de cerco e 32 com malhadeira. O presente trabalho mostra a importância de se utilizar diferentes apetrechos de coleta como forma de diminuir a seletividade inerente de cada um desses aparelhos, melhorando a efetividade de amostragens em ambientes pouco estudados. PALAVRAS-CHAVE: Ictiofauna, riqueza de espécies, malhadeira, rede de cerco. Comparison of the relative efficiency of two fishing gears in sandy beaches in lower Purus river, Amazonas, Brazil ABSTRACTDespite representing one of the seven most important aquatic habitats in the Amazon, little has been done concerning fish inventories on sandy beaches, especially related to the fishing gear used in these environments. This study aims to compare the relative efficiency of two fishing gears, seine and gill-net, used actively (trawling), on three sandy beaches on the lower reaches of Rio Purus. Seining resulted in a larger number of species and specimens, whereas for total biomass, gill-nets showed larger values, mainly represented by Siluriformes. Low similarity between samples (38%) was due to different catches of each gear: 41 species collected only with seine and 32 only with gill-net. The present study strengthens the importance of using different fishing gears in experimental fisheries as a way to overcome the inherent selectivity of each gear, and thus improving the efficacy of sampling in poorly-known environments.

Fish Fauna in Oxbow Lakes of the Middle Purus River in the Neotropical Region of the Amazon Rainforest

“…Thus, information on fish assemblages that occur in oxbow lakes of the Middle Purus River is an important resource for gathering data on the richness of fish species, thereby contributing to the knowledge and conservation of the ichthyofauna of the Amazon Rainforest. Considering that the existing studies on fish species in the Purus river basin are concentrated in the upper Purus River and lower Purus River (RAPP-PY-DANIEL; DEUS, 2003;DUARTE et al, 2013), the oxbow lake system is of central importance for studies related to the ichthyofauna. In this context, the present study describes fish fauna inhabiting twelve oxbow lakes of the Middle Purus River, and evaluate the influence of hydrological connectivity in the number of species of fish between the hydrological periods.…”

Redescription of Moenkhausia megalops (Eigenmann, 1907), a widespread tetra from the Amazon basin (Characiformes, Characidae)

“…Although we were not able to confirm these informations, there are also records of occurrence of M. megalops for other rivers in the Amazon basin that were not included in our Geographic distribution section, such as rio Purus (Duarte et al 2013), and from Colombia (Maldonado-Ocampo 2001, Arbeláez et al 2004, Maldonado-Ocampo et al 2008Miller-Hurtado et al 2009), and Venezuela (Lasso et al 2004, Gonzáles et al 2012). However, we analyzed photographs of specimens from Rio Orinoco, Venezuela (ANSP 190778;ANSP 191245) that presents the diagnostic humeral and caudal marks of M. megalops and could be tentatively identified as this species.…”

Ichthyofauna associated with sandy beaches of the rio Machado, tributary of the rio Madeira, northern Brazil

“…Research on the freshwater ichthyofauna of benthic habitats has focused mainly on sandy beaches along the margins of rivers (Ibarra and Stewart 1989;Stewart et al 2002), and the literature on Amazon fishes in sandy beaches is extremely scarce (Goulding et al 1988;Ibarra and Stewart 1989;Jepsen et al 1997;Stewart et al 2002;Arrington and Winemiller 2003;Duarte et al 2010Duarte et al , 2013Carvalho et al 2014;Silva et al 2019). The scarcity of information on this subject is mainly due to the seasonality of the habitat: the vast majority of sandy beaches are exposed only three months of the year (Santos and Ferreira 1999;Duarte et al 2010).…”