The Breco Bird Scarer aquatic scaring device proves ineffective as a waterbird deterrent during trials in the San Francisco Bay estuary, California, USA

  • Published source details Whisson D.A. & Takekawa J.Y. (2000) Testing the effectiveness of an aquatic hazing device on waterbirds in the San Francisco Bay estuary of California. Waterbirds, 23, 56-63


This study is summarised as evidence for the following.

Action Category

Use visual and acoustic ‘scarers’ to deter birds from landing on pools polluted by mining or sewage

Action Link
Bird Conservation
  1. Use visual and acoustic ‘scarers’ to deter birds from landing on pools polluted by mining or sewage

    A replicated, controlled trial at two sites in San Francisco Bay, California (USA) found that the Breco Bird Scarer (an orange buoy designed to drift with an oil slick) did not alter waterbird behaviour when it was broadcasting sounds as opposed to non-broadcasting (Whisson & Takekawa 2000). The buoy broadcasts up to 30 different sounds at up to 130 dB at 1 m, at varying intervals (30 sec to 5 min, dependent on how programmed). Alternating 2-day treatment (device ‘on’) and control (‘off’) periods were conducted. No significant deterrent effect was noted on numbers of three common wintering duck species (greater and lesser scaup Aythya affinis and A. marila, surf scoter Melanitta perspicillata) and all other waterbirds.


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