Elsevier

Fisheries Research

Volume 82, Issues 1–3, December 2006, Pages 280-289
Fisheries Research

The traditional shark fisheries of southwest Madagascar: A study in the Toliara region

https://doi.org/10.1016/j.fishres.2006.06.016Get rights and content

Abstract

Traditional shark fisheries in Africa are largely poorly documented. Fisheries management plans for fisheries targeting chondrichthyan species are typically based on studies with limited spatial resolution or detail, compromising their efficacy and potentially reducing the effectiveness of national and regional plans. Southwest Madagascar is an area poorly documented with regard to many of its marine resources. This study presents a detailed investigation of the directed shark fisheries of two villages south of Toliara – Soalara and Maromena – presenting a description of the fishery in these villages and catch data for periods of 13 and 10 months, respectively. Results from a total of 1164 catch records, including members of at least 13 species, with an estimated total wet weight of over 123 mt are reported, with hammerhead sharks (Sphyrna spp.) representing 29% of sharks caught and 24% of the total wet weight. There is an active export market for the fins resulting from the fisheries, indicating a considerable social and economic importance in this impoverished region of Madagascar. The fisheries are showing signs of decline, possibly as a result of changing to less selective fishing gear, as a result of the intervention from outside agencies.

Introduction

The industrial, artisanal and traditional shark fisheries of Madagascar have been the subjects of studies dating back as far as 1930 (Petit, 1930). In the past decade the emphasis of this work has shifted from investigations of the species involved towards assessing the scale of these fisheries, the status of shark stocks involved and discussions of the management implications of these findings (Smale, 1998, Cooke, 1997, du Feu, 1998, Cooke et al., 2003). The majority of these studies have focussed on fisheries in the North of Madagascar, with limited information available for the region south of Toliara, especially concerning the traditional, canoe-based, fisheries. Information available for this region consists largely of fishery descriptions, details of species fished and reported marine production statistics that are known to be of variable completeness for reasons of periodic political instability within Madagascar (Cooke, 1997, FAO, 1998).

The aim of this study was to conduct an extended investigation into the traditional (here taken as “fishing conducted on foot or in non-motorised vehicles” as defined by the Malagasy fisheries law (93-022) and outlined in Cooke, 1997) shark fisheries of two villages south of Toliara – Soalara and Maromena – in southwest Madagascar (Fig. 1), through the collection of catch data directly from the villages themselves. The study produced surprising results regarding the scale of the shark fisheries and highlighted the changes that have occurred within these fisheries since they were last surveyed in 1995 (Salimo et al., 1995, referred to in Cooke, 1997), largely as a result of the intervention of external agencies. The scale of these fisheries and anecdotal reports of changes in catch composition and reductions in catch per unit effort suggest that the shark fishery in this region may be in decline. Such a decline could have significant consequences for the local communities due to the socio-economic importance of shark fishing to the villages surveyed.

Section snippets

Study area

The study was carried out from October 2001 to October 2002. Initially only one village was selected for this study, “Soalara-Bas” (hereafter referred to only as Soalara), situated approximately 30 km South of Toliara (23°35′S, 43°44′E), southwest Madagascar (Fig. 1). The migratory nature of the fishers studied, however, resulted in this study being extended in January 2002 to the villages of Maromena and Befasy (approximately 30 and 35 km South of Soalara, respectively) (Fig. 1). Both Maromena

Description of the fishery

The shark fisheries of Soalara, Beheloka, Maromena and Befasy employed 6–8 m long traditional sailing “pirogues” consisting of a hull and outrigger with a square sail, crewed on average by two fishers. Boats crews would go out to retrieve catch and re-bait there passive fishing gears on a daily basis, weather permitting, with fishers estimating approximately 300 fishing days per year.

The fishing gears employed were static, surface-set, long line sets (palangres) and gill nets (jarifas). Long

Discussion

The scale of these fisheries was largely unexpected, with over 123 mt of sharks estimated to have been fished within 13 months. This figure greatly exceeds the estimated mean annual catch of 500 kg of elasmobranches per km of coastline in Madagascar stated by Kroese and Sauer (1998) in their review of African elasmobranch fisheries, a worrying underestimate when you consider that there are at least 14 other similar villages that exploit sharks within 100 km of the study area (den Haring, pers.

Acknowledgements

We would like to acknowledge the help and support of the staff and research assistants of Frontier-Madagascar, a collaboration of L’Institut Halieutique et des Sciences Marine and the Society for Environmental Exploration. We would also like to thank the fishermen and residents of the villages surveyed for their co-operation and patience and Al Harris of Blue Ventures for the map in Fig. 1. This work was funded by the Society for Environmental Exploration.

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