(Madagascar) The potential ecological and fisheries impacts of beach seine net fishing in SW Madagascar

Fieldwork in Madagascar required.

The use of fine mesh fishing nets to fish in shallow lagoonal environments is recognised as a highly unsustainable and destructive fishery in many east African and Indian Ocean coastal states. In Madagascar, fisheries legislation prohibits the use of fishing nets below a mesh size of 25mm (Article 10, Decree 5 1922). However due to a lack of surveillance capacity national fisheries services have weak capacity to enforce legislation and the practice of beach seine fishing is widespread throughout the country (Rakotoson and Tanner 2006).

In southwest Madagascar the method is often employed by itinerant migrant fishers, or by those to whom other fishing techniques are unknown or unavailable. The practice is widely disapproved of by communities of traditional Vezo fishers, due to its non-selectivity and capture of juvenile fish (Dalzell 1996, Andriamalala 2008).

In this region beach seine net fishing (Tarikaky) often uses large lengths (>500m) of illegal mesh size nets in an effort to capture the small fish that are missed by other larger meshed gill nets. Nets include mosquito nets, which are often in abundance following distribution programmes by health agencies and NGO. The method typically employs between 4 and 21 fishermen/women, and has been documented to land catches of up to 50kg in a single day although in areas where beach seining is more frequently used fishers have reported regular catches of less than 5kg.

Beach seine nets are deployed in a shallow lagoonal habitat. Fishers haul the net by ropes towards the beach. Other assisting fishers dive around the nets, both in order to lift the weight line over rocks or corals that could potentially damage the net, as well as to catch any escaping fish using spears (Gough et al 2009).

The use of such unselective fishing techniques has been widely documented to have serious implications for fisheries sustainability and ecosystem function (Dalzell 1996, McClanahan and Mangi 2004), and at a recent meeting of government officials, marine conservation organisations and community leaders in southwest Madagascar, beach seine net fishing was identified as the top threat to the sustainability of small-scale traditional fisheries in the region. Yet despite widespread national concerns a growing movement towards the promotion of sustainable fisheries, little is known of the consequences of these fishing gears and techniques on species diversity, size, trophic level, selectivity and catch composition

This project proposes to profile the beach seine fishery of southwest Madagascar through the analysis of landings and habitat assessments, to include;

CPUE and catch composition comparisons between beach seine fisheries and non seine net fisheries, to include species and trophic guild

Assessment of the destructive action of beach seine methods through quantitative habitat assessments in beach seine and non beach seine areas

The results of this study are hoped to aid management decisions and the development of effective behavior change strategies to be implemented by; local communities, local and regional authorities and other fisheries management bodies in the management of beach seine fishing in south west Madagascar.

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