Play predator calls to deter mammals from fishing gear

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

Study locations

Key messages

  • One study evaluated the effects of playing predator calls to deter mammals from fishing gear. The study was in the South Atlantic Ocean (Africa).





  • Human-wildlife conflict (1 study): One study in the South Atlantic Ocean found that playing killer whale vocalisations did not deter Cape fur seals from feeding on fish catches in a purse-seine net or trawl net.

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 study in 1974 of pelagic sites in the South Atlantic Ocean, off the coast of southern Africa (Shaughnessy et al. 1981) reported that playing killer whale Orcinus orca vocalizations underwater did not deter Cape fur seals Arctocephalus pusillus from fishing nets. Results are not based on assessments of statistical significance. During two trials with a purse-seine net, all of 15–25 seals feeding in the net responded to killer whale vocalizations by diving. Some seals (48–100%) initially moved out of the net but all returned within 30 seconds. The authors report that floating two life-sized models of killer whale dorsal fins amongst the seals during one of the trials did not affect seal behaviour (no data provided). Results were similar during a trial at a trawl net (data not reported). Recordings of killer whale vocalizations (clicks, whistles, squeaks) were played back through an underwater loudspeaker. Two trials (each with 2–14 minutes of playback) were carried out by a purse-seine fishing vessel with the net pursed to a 10-m diameter. One trial was carried out by a side-trawler vessel with the ‘cod-end’ (containing fish) in the water. Observers on board the fishing vessels recorded seal behaviour during each of the three trials in 1974.

    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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