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