Fishers' resource mapping and goliath grouper Epinephelus itajara (Serranidae) conservation in Brazil

Leopoldo Cavaleri Gerhardinger,Mauricio Hostim-Silva,Matheus Oliveira Freitas,Rodrigo Pereira Medeiros,José Matarezi,Áthila Andrade Bertoncini,Beatrice Padovani Ferreira

doi:10.1590/s1679-62252009000100012

Abstract

Goliath grouper (Epinephelus itajara) aggregations and relative abundances were described and mapped through the use of fishermen's local ecological knowledge in Babitonga Bay in southern Brazil. Six well-experienced informants were asked to individually provide information about goliath grouper abundance and distribution, drawn over a satellite image of the study area, which was later overlaid and gathered into a final map. According to our informants, the goliath grouper occurs along a broad salinity and depth range, from shallow estuarine areas (less than 5 m deep) with high freshwater input (smaller individuals, up to 150 kg) to coastal marine-dominated environments (at least 35 m deep); (larger individuals more common, frequently reaching more than 300 kg). Fishermen referred to goliath groupers inhabiting hard substrates such as rocky reefs around islands and continental shores, submerged rocky outcrops and shipwrecks (juveniles and adults). At least two aggregation sites mapped (ranging from 2 to 60 individuals) could be concluded as spawning aggregation sites through evidence of high abundance and spawning activity. Priority research and conservation targets were identified and discussed for Babitonga Bay (e.g., design of a tagging experimental program and establishment of a marine protected area). Fishers' resource mapping provided a means of exchanging information among various disciplines while maintaining methodological rigor in a clear and straightforward way of presenting fishers' knowledge. The use of fishers' sketch maps is a promising tool for marine conservation in Brazil, with special regard to adaptive co-management regimes, where frequent environmental re-evaluations are needed.

Highlights

Data required for decisions in marine resource management are frequently regarded as insufficient or inexistent, especially when considering small geographic scales (Johannes, 1998; Anuchiracheeva et al, 2003; Drew, 2005)
Fishermen’s local ecological knowledge (LEK) and traditional practices can play a central role in local marine resource management (Haggan et al, 2007)
Goliath grouper distribution and habitat use According to our informants, E. itajara is present in areas of estuarine- (Fig. 2a) to marine-dominated environments (Fig. 2b)

Summary

Introduction

Data required for decisions in marine resource management are frequently regarded as insufficient or inexistent, especially when considering small geographic scales (Johannes, 1998; Anuchiracheeva et al, 2003; Drew, 2005). In the last two decades, interest in fishermen’s LEK has increased significantly (Ruddle, 1994; Huntington, 2000; Diegues & Arruda, 2001; Davis & Wagner, 2003). Examples of such studies in Brazil include folk taxonomy (Paz & Begossi, 1996), research examining fishers’ knowledge of feeding (Costa-Neto et al, 2002), reproductive cycles (Silvano et al, 2006), general aspects of the ecology of marine fishes (Gerhardinger et al, 2006) or ecosystems, and behavior and social-ecological changes (Seixas & Berkes, 2003)

Objectives

Methods

Results

Discussion

Conclusion