Skip to main content

Research Repository

Advanced Search

An examination of the techniques used to capture mangrove crabs, Ucides cordatus, in the Mamanguape River estuary, northeastern Brazil, with implications for management

Nascimento, Douglas Macêdo; Alves, Ângelo Giuseppe Chaves; Alves, Rômulo Romeu Nóbrega; Barboza, Raynner Rilke Duarte; Diele, Karen; Mourão, José Silva

Authors

Douglas Macêdo Nascimento

Ângelo Giuseppe Chaves Alves

Rômulo Romeu Nóbrega Alves

Raynner Rilke Duarte Barboza

José Silva Mourão



Abstract

The present research, undertaken in a mangrove swamp in northeastern Brazil (Mamanguape River Estuary), examined the factors that led to the overwhelming acceptance of the tangle-netting technique by crab harvesters in detriment to the now illegal tamping technique. Both techniques are the only ones currently used at our study site and in many other areas in Brazil, despite being prohibited by law. Data were collected through direct observations to determine capture efficiency, productivity, daily production, selectivity, and harvesting effort, and through interviews with crab harvesters, focusing on their perceptions of the capture techniques, the conditions of crab stocks and the sales price of a dozen crabs. Our results indicated that the two capture techniques did not significantly differ in terms of their efficiency or productivity, but daily production rates differed significantly, being greater using tangle-netting. The tangle-netting permits a greater harvesting effort (6 hours and 34 min) compared to tamping (4 hours and 19 min). Tangle-netting is also less selective than tamping indicated by the larger number of captured smaller specimens, including females. This results in a lower average sales price for a dozen crabs caught by tangle-netting (US$ 0.95) compared to tamping (US$ 1.02). The greater daily production of crab harvesters using the tangle-netting technique nevertheless increased their net gain, explaining their preference for this method, Given that tangle-netting results in greater harvesting pressure but lower selectivity compared to tamping, it may potentially be less sustainable. All of the crab harvesters interviewed having more than 20 years of experience (n = 34) stated they perceived that stocks of U. cordatus had become reduced over the last 20 years, together with average crab sizes. It is now important to examine the structure of the local U. cordatus population and to assess its fishery to allow evaluating whether the illegal, but prominent tangle-netting and tamping mangrove crab capture techniques are sustainable or not. We further suggest improving the dialogue between decision makers and fishermen, which barely exists to date, to initiate a discussion about possible ways of resolving the current situation of illegality of the fishermen. This will be key to achieving effective sustainable co-management of this important natural mangrove forest resource.

Citation

Nascimento, D. M., Alves, Â. G. C., Alves, R. R. N., Barboza, R. R. D., Diele, K., & Mourão, J. S. (2016). An examination of the techniques used to capture mangrove crabs, Ucides cordatus, in the Mamanguape River estuary, northeastern Brazil, with implications for management. Ocean and Coastal Management, 130, 50-57. https://doi.org/10.1016/j.ocecoaman.2016.05.010

Journal Article Type Article
Acceptance Date May 27, 2016
Online Publication Date Jun 5, 2016
Publication Date 2016-10
Deposit Date May 30, 2016
Publicly Available Date Jun 5, 2016
Journal Ocean and Coastal Management
Print ISSN 0964-5691
Electronic ISSN 1873-524X
Publisher Elsevier
Peer Reviewed Peer Reviewed
Volume 130
Pages 50-57
DOI https://doi.org/10.1016/j.ocecoaman.2016.05.010
Keywords Artisanal fishing; crab harvesters; crustaceans; sustainability;
Public URL http://researchrepository.napier.ac.uk/id/eprint/10298
Contract Date May 30, 2016

Files

An examination of the techniques used to capture mangrove crabs, Ucides cordatus, in the Mamanguape River estuary, northeastern Brazil, with implications for management (252 Kb)
PDF


An examination of the techniques used to capture mangrove crabs... (1.6 Mb)
Document


DieleTitle Page with all author info.docx (13 Kb)
Document






You might also like



Downloadable Citations