Octopus stock assessment of reef flats around Andavadoaka, Madagascar

Student background
Students should have a good knowledge of marine fisheries assessment methods, and an undergraduate or masters level degree in marine sciences, resource management or a related discipline.

Aim of the Project
Recent commercialisation of octopus fisheries in the Andavadoaka region has lead to increased fishing pressures on octopus and anecdotal reports suggest that both numbers and sizes are declining.

Weighing octopus catches

Since September 2004, details of octopus catches have been recorded by a network of ‘sous collectors’, who purchase the octopus directly from the fishers. These sous collectors are employed by Blue Ventures in eight villages to collect data needed for developing our understanding of the sustainability of the region’s octopus fishery. Individual weights, dates and fishing grounds for each octopus have been recorded since September 2004 (with some collection data going back to March 2004), and since November the names, ages and methods for each fisher have also been recorded. Through an understanding of the octopus life cycles and fishing pressures, it may be possible to model growth rates and estimate sustainable levels of fishing.

Proposed methods
The candidate should decide on whether CpUE (Catch per Unit Effort), surplus yield modelling or dynamic pool modelling is an appropriate focus for this research. In the field the candidate can collect data from the collectors and interview them (providing French skills are adequate). He or she could spend time with octopus fishers studying methods, duration spent fishing and sites used.

Background research
Background research on species and assessment methods will be essential before entering the field.