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Providing evidence to improve practice

Individual study: 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: The International Journal of Waterbird Biology, 23, 56-63


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

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

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.