Capture techniques' use of Caranguejo-uçá crabs (Ucides cordatus) in Paraíba state (northeastern Brazil) and its socio-environmental implications

Abstract

The present study was undertaken in two traditional communities that are located on the margins of the estuary and mangrove complex of the Mamanguape River, Paraíba state (PB), Brazil. This work describes the crabs capture techniques tapamento and redinha, and identifies the negative socio-environmental impacts of redinha, using qualitative methods (open and semi-structured interviews, guided tours, direct observation and the administration of questionnaires). Results indicate that currently only two principle techniques are used to capture Ucides cordatus: redinha and tapamento. Tapamento has a low impact in relation to redinha. Redinha was pointed out by interviewees as a system that has social impact (social conflicts, breaking of traditions, substitution and extinction of techniques) and environmental impact (less selective captures and high productivity, mangrove pollution, death of crabs caught in traps, cutting of the roots of Rhizophora mangle, micro-habitat loss resulting from galleries destroyed and polluted). Knowledge of crab harvesting carried out using these two techniques and the possible social and environmental impacts caused by redinha, can lead to more effective planning and actions towards the conservation of the species.

Trophic connectivity and basal food sources sustaining tropical aquatic consumers along a mangrove to ocean gradient

“…This estuary harbors a great variety of habitats including sandy coastal beaches bordered by field dunes, coastal reefs with dense mats of macroalgae, seagrass beds (Halodule wrightii), restinga forests, tableland forests and a wellpreserved mangrove area with approximately 6,000 hectares (Silvestre 2011, Xavier et al 2012. An important feature in this costal system is an 8.5 m long barrier reef perpendicular to the shoreline, which creates a protected region at the mouth of the estuary (Nascimento, 2012). The regional climate is characterized by dry and wet periods that occur from October to April and May to September, respectively (Barletta et al 2009).…”

“…This method consists of setting up multifilament fishing nets at the edge of the mangrove wetland at the peak of the high tide and removing the nets during the following low tide (Bezerra et al 2012). Infaunal organisms were collected using PVC tube (10 cm in diameter, area of 0.0078 m 2 ).…”

Ethnozoology in Brazil: analysis of the methodological risks in published studies

“…Overall, it can be said that a great part of ethnozoological research addresses invertebrate groups, particularly crustaceans and insects (see Alves and Dias, 2010;Ulysséa et al, 2010;Alencar et al, 2012;Nascimento et al, 2012). Regarding vertebrates, most of the studies are performed on fish (see Mourão and Nordi, 2006;Clauzet et al, 2007;Silvano and Valbo-Jørgensen, 2008;Lopes, et al, 2009;Begossi et al, 2012).…”

Habits and customs of crab catchers in southern Bahia, Brazil

“…According to Nascimento et al [60], due to its high productivity and ease of use, the tangle-netting technique has spread rapidly throughout most crab catcher communities and threatens traditional capture techniques, the mangrove ecosystem and the U. cordatus population.…”