Use traps instead of fishing nets

Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
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How is the evidence assessed?

Effectiveness

40%
Certainty

32%
Harms

20%

Calculating overall effectiveness category

Background information and definitions

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.}

Study locations

Key messages

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.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

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).
Study and other actions tested
Referenced paper
Amengual-Ramis J.F., Vázquez-Archdale M., Cánovas-Pérez 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.

Please cite as:

Lemasson, A.J., Pettit, L.R., Smith, R.K. & Sutherland, W.J. (2020) Subtidal Benthic Invertebrate Conservation. Pages 635-732 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

This Action forms part of the Action Synopsis:

Subtidal Benthic Invertebrate Conservation

Related Actions

Actions	Effectiveness	Studies	Category
Fit one or more soft, semi-rigid, or rigid grids or frames and increase the mesh size of pots and traps Action Link	Unknown effectiveness (limited evidence)	1	Synopsis Link
Use traps instead of fishing nets Action Link	Unknown effectiveness (limited evidence)	1	Synopsis Link
Use a larger mesh size on trammel nets Action Link	Unknown effectiveness (limited evidence)	1	Synopsis Link