Acoustic pingers eliminate beaked whale bycatch in a gill net fishery

  • Published source details Carretta J.V., Barlow J. & Enriquez L. (2008) Acoustic pingers eliminate beaked whale bycatch in a gill net fishery. Marine Mammal Science, 24, 956-961.


This study is summarised as evidence for the following.

Action Category

Use acoustic devices on fishing gear

Action Link
Marine and Freshwater Mammal Conservation
  1. Use acoustic devices on fishing gear

    A before-and-after study in 1990–2006 of multiple pelagic sites in the North Pacific Ocean, off the coasts of California and Oregon, USA (Carretta et al. 2008; same fishery as Barlow & Cameron 2003 and Carretta & Barlow 2011) found that using acoustic devices on fishing nets reduced the number of beaked whale (Ziphiidae) entanglements. No beaked whales were found entangled in fishing nets during the 11 years in which acoustic devices were used, whereas 33 whales of at least six species were entangled during the six years before the devices were used (see original paper for details). In 1990–1995, a total of 3,303 nets were deployed without acoustic devices. In 1996–2006, a total of 4,381 nets were deployed with acoustic devices attached at 91 m intervals (average 40 devices/net). The devices emitted 300 ms pulses at 10–12 kHz. Each of the 7,684 ‘drift’ gill nets (1,800 m long x 65 m deep) was deployed from dusk until dawn at depths of 11–90 m to catch swordfish and sharks. Observations of entangled whales were made by biologists on board fishing vessels in 1990–2006.

    (Summarised by: Anna Berthinussen)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust