Action: Use traps instead of fishing nets
Key messagesRead our guidance on Key messages before continuing
- One study examined the effects of using traps instead of fishing nets on subtidal benthic invertebrates. The study took place in the Mediterranean Sea (Spain).
COMMUNITY RESPONSE (0 STUDIES)
POPULATION RESPONSE (1 STUDY)
- Unwanted catch abundance (1 study): One replicated, controlled study in the Mediterranean Sea found that the combined amount of unwanted catch of invertebrates and fish appeared lower using plastic traps than trammel nets, but higher using collapsible traps.
OTHER (1 STUDY)
- Commercial catch abundance (1 study): One replicated, controlled study in the Mediterranean Sea found that the catch of commercially targeted lobsters was lower using traps than in trammel nets.
Fishing nets can have poor selectivity, leading to high amounts of unwanted catch, and also can negatively impact the seabed and benthic communities due to physical contact and disturbance (Amengual-Ramis et al. 2016). Although fishing nets and traps usually target different species and are used in different fisheries, in certain cases, they can target and catch the same species. Replacing fishing nets with traps and pots where feasible can help reduce the impacts on invertebrate populations, through a reduction in physical disturbances and a reduction in unwanted catch. For instance, trammel nets used in lobster fisheries could be replaced with traps (Amengual-Ramis et al. 2016).
Evidence for other interventions related to trap and pot fishery is summarised under “Threat: Biological resource use – Modify the position of traps”, “Modify the design of traps”, “Use a different bait species in traps”, “Fit one or more soft, semi-rigid, or rigid grids or frames on pots and traps” and “Fit one or more mesh escape panels/windows on pots and traps”.
Amengual-Ramis J.F., Vazquez-Archdale M., Canovas-Perez C. & Morales-Nin B. (2016) The artisanal fishery of the spiny lobster Palinurus elephas in Cabrera National Park, Spain: comparative study on traditional and modern traps with trammel nets. Fisheries Research, 179, 23–32.
Supporting evidence from individual studies
A replicated, controlled study in 2011–2012 of seabed composed of mud, kelp, and maërl, off the southeastern coast of Mallorca, Mediterranean Sea, Spain (Amengual-Ramis et al. 2016) found that experimental designs of lobster traps appeared to catch different combined amounts of non-commercial unwanted invertebrates and fish (discard) than commercially used trammel nets, but the amount varied with trap design. Data were not statistically tested. When comparing similar length-deployment for each fishing design, the amount of discard caught in plastic traps (3 individuals/450 m) tended to be lower than in trammel nets (5.7), but higher in collapsible traps (16). Catches of legal-size commercially targeted lobsters tended to be lower in traps (0–0.3 lobsters/450 m) than in trammel nets (1.3). In May–September 2011, traps (900/design) were deployed at 50–100 m depth for 24h (see paper for details of each design). Lobsters and unwanted species caught were counted and measured in each trap. Baited traps were deployed in two 450 m-long strings of 30 traps each (one line/design; >200 m apart). In May–August 2012, similar data for trammel nets were obtained onboard commercial vessels (119 nets, 50 m each, deployed overnight).