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Providing evidence to improve practice

Individual study: Fishing methods for sustainable shrimp fisheries in the Canary Islands (North-West Africa)

Published source details

Arrasate-López M., Tuset V., Santana J., García-Mederos A., Ayza O. & González J. (2012) Fishing methods for sustainable shrimp fisheries in the Canary Islands (North-West Africa). African Journal of Marine Science, 34, 331-339

This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Modify the position of traps Subtidal Benthic Invertebrate Conservation

A replicated, controlled study in 2003–2004 at four different water depths in areas of rocky seabed around the Canary Islands, North Atlantic Ocean, Spain (Arrasate-López et al. 2012) found that using semi-floating shrimp traps instead of traditional bottom traps appeared to reduce the catch and biomass of unwanted non-commercial species (discards) and unwanted commercial species (here referred to as bycatch), consistently across water depths. Results were not tested for statistical significance. Across water depths, semi-floating traps tended to catch fewer discard species of lower biomass (1–3 species; 0.006–0.6 g/trap/day) compared to bottom traps (2–4 species; 1–23 g/trap/day), and fewer bycatch species of lower biomass (semi-floating: 0–4 species, 0–18 g/trap/day; bottom: 1–6 species, 59–363 g/trap/day). The overall number and biomass of commercially targeted prawn species caught tended to be similar using semi-floating traps (2–6 species; 20.5–135 g/trap/day) and bottom traps (3–5 species; 16.6–107.3 g/trap/day), but the trap types caught different species. Four surveys were undertaken between October 2003 and October 2004. During each survey, an unspecified number of baited bottom traps and semi-floating traps (2 m above the seabed) were deployed at 100 m depth intervals between 120 and 1,300 m depths for 15–25 h. The number and biomass of bycatch, discard, and commercially targeted species were recorded. Data for a total of 487 bottom traps and 1,971 semi-floating traps were collected.

(Summarised by Anaëlle Lemasson)