Use an electric current to deter mammals from fishing gear

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

  • One study evaluated the effects of using an electric current to deter mammals from fishing gear. The study was in the Fraser River (Canada).





  • Human-wildlife conflict (1 study): One controlled study in the Fraser River found that using an electric current on a fishing net reduced Pacific harbour seal predation on salmon catches.

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

  1. A controlled study in 2007 at a site in the Fraser River, Canada (Forrest et al. 2009) found that using an electric current on a fishing net reduced Pacific harbour seal Phoca vitulina richardsi predation on catches of salmon Oncorhynchus spp. A section of fishing net treated with an electric current had higher catch rates of salmon (4 fish/km/minute) than an untreated section without an electric current (1 fish/km/minute). Seals were observed avoiding the electric section of the net (numbers not reported). An experimental nylon gill net (diagonal mesh size 133 mm, 60 meshes deep) was divided into two 91-m sections. One section was treated with a pulsed low-voltage electric current (produced by two horizontal wire electrodes spaced 2 m apart). The other section had no treatment. The net was deployed for 20 minutes three times/day on 22 days in August–September 2007. The electric treatment was alternated between the two sections of net. An observer on board the fishing vessel recorded salmon catches during a total of 67 net deployments.

    Study and other actions tested
Please cite as:

Berthinussen, A., Smith, R.K. and Sutherland, W.J. (2021) Marine and Freshwater Mammal Conservation: Global Evidence for the Effects of Interventions. Conservation Evidence Series Synopses. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

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Marine and Freshwater Mammal Conservation

This Action forms part of the Action Synopsis:

Marine and Freshwater Mammal Conservation
Marine and Freshwater Mammal Conservation

Marine and Freshwater Mammal Conservation - Published 2021

Marine and Freshwater Mammal Synopsis

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