Fishes collected with an artisanal fish trap in Barra de Camaratuba estuary, northeastern Brazil

: A list of the species of fishes collected in the Barra de Camaratuba estuary, Paraiba, Brazil, is presented. Specimens were collected on a monthly basis between January and December 2012, using a fishing technique known locally as “Tomada”, an artisanal fish trap like a barrier. Forty species were collected, belonging to 27 genera and 20 families of the Teleostei. The Gerreidae was the most representative family, with 6 species, followed by the Lutjanidae and Tetraodontidae, with four species each.


Introduction
Fishes, with about 28,000 valid species (Nelson 2006), have a wide variation in morphology and biology, inhabiting marine, estuarine and freshwater environments. They are important not only for the adequate functioning of the aquatic environments, but also as food supply and income generation, mainly for local communities.
Local estuarine fishermen in the Brazilian northeastern coast traditionally use the "Tomada", a type of net barrier, as a common fishing practice. This fishing method consists of setting trapping barriers made of fishing nets, so that the fish that enter the mangrove channels are kept trapped along the maximum length permitted by the physical geography of the site. The fishing nets are set during low spring tide. They are suspended with high tide, enabling the capture of fish that enter the estuary. In order to score and lift the nets, fishermen use roots and branches of local vegetation, Rhizophora mangle L. For temporary net barriers he outlets of the tidal flat or mangrove border are blocked by a net approximately 200 m long and 3 m high. The net is positioned during high tide and fastened on wooden poles, which are stuck in the mud after the fish have step into the inundated mangroves. Fish are collected from the small pools that form during the low tide, six hours after locking up the tidal flat. The "Tomada" differs from another fishing technique, the "Tapagem", which is widely used in the north-northeastern Brazil. "Tapagem" consists of a trap used by fishermen in the tidal creek, at the mouth of small rivers and streams that are influenced by the tide (Nery 1995;Barletta et al. 1998).
The "Tomada" is a fishing practice with low selectivity level in terms of the fish species caught, and captures both adults and juveniles. Therefore, this fishing practice might have an impact on the ecosystem. Despite this, there is very little information regarding Fishes collected with an artisanal fish trap in Barra de Camaratuba estuary, northeastern Brazil Abstract: A list of the species of fishes collected in the Barra de Camaratuba estuary, Paraiba, Brazil, is presented. Specimens were collected on a monthly basis between January and December 2012, using a fishing technique known locally as "Tomada", an artisanal fish trap like a barrier. Forty species were collected, belonging to 27 genera and 20 families of the Teleostei. The Gerreidae was the most representative family, with 6 species, followed by the Lutjanidae and Tetraodontidae, with four species each. DOI: 10.15560/10.6.1260 The relative abundance was calculated as RA = n sp × 100/T, were RA = relative abundance; n sp = number of individuals of each species; T = total of individuals. For each species, the constancy was calculated as C = (p/P) × 100, were p = number of samples in which the species was recorded and P = total number of samples and the species were grouped in Constant (present in over 50% of the samples); Accessory (present in 25 to 50% of the samples) and Accidental (present in under 25% of the samples) (Dajoz 1983).

Discussion
The local fishermen use regularly the "Tomada" to capture fish to be sold at the open fair in Mataraca Municipality. They usually sell Mugil curema, Centropomus parallelus, C. pectinatus, C. undecimalis and Eugerres brasilianus. These species are caught by this fishing technique all year around (100% Constancy), this shows that the goal with using this fish trap is reached by fishermen. But for the total of species, most of them were considered Accidental, as it is common in estuarine fishes (Viana et al. 2010).
The trap fisheries represents a small-scale fisheries and appear more balanced, exhibiting relatively few conflicts and in some cases, such as fish traps, present a number of traditional management measures that constitutes a form of management and control of fishery effort (Isaac et al. 2009). Nevertheless we note that the most part of the trapped specimens lack economic interest and are usually discarded by fishermen, which denotes the impact of this traditional fishing practice either in resident species or about those that use the estuary as growth and recruitment areas. Thus, like a first local assessment, this study demonstrates the ecological impact of a traditional fishing practice.    List of species of the Teleostei collected in Barra de Camaratuba estuary in 2012 (n = number of individuals; RA = relative abundance (%); C = constancy (C = Constant; As = Accessory; Ad = Accidental). Classification by Betancur-R. et al. (2014).