Study

Echolocation behavior of harbor porpoises Phocoena phocoena around chemically enhanced gill nets

  • Published source details Cox T.M. & Read A.J. (2004) Echolocation behavior of harbor porpoises Phocoena phocoena around chemically enhanced gill nets. Marine Ecology Progress Series, 279, 275-282

Actions

This study is summarised as evidence for the following.

Action Category

Use acoustically reflective fishing gear materials

Action Link
Marine and Freshwater Mammal Conservation
  1. Use acoustically reflective fishing gear materials

    A controlled study in 2000 of a pelagic area in the Bay of Fundy, Canada (Cox & Read 2004) found that fishing nets made from acoustically reflective materials (barium sulfate) had similar harbour porpoise Phocoena phocoena echolocation activity around them compared to conventional nets. The average occurrence and rate of porpoise echolocation clicks were similar at barium sulfate nets (18–54 intervals with clicks/h; 32–52 clicks/h) and conventional nets (17–57 intervals with clicks/h; 18–54 clicks/h). Average catches of target groundfish species did not differ significantly between barium sulfate nets (0.41 fish/h) and conventional nets (0.38 fish/h). In July–August 2000, nine barium sulfate and 14 conventional gill net strings were deployed across a fishing area (same study site and nets as Trippel et al. 2009). All strings (comprising 3 x 100 m nets, 15 cm stretched monofilament mesh) were deployed on the ocean bottom at depths of 100–130 m for 24–72 h. Four acoustic detectors attached to each of the 23 net strings continuously recorded porpoise echolocation activity at 10 second intervals for a total of 225 h on barium sulfate nets and 366 h on conventional nets.

    (Summarised by: Anna Berthinussen)

Output references

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, terrestrial 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 18

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 Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust