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Providing evidence to improve practice

Individual study: An inexpensive radar-activated scaring system reduces avian landings on a 18.2 ha desulfurization pond, USA

Published source details

Johansson C.A., Hardi P.J. & White C.M. (1994) An inexpensive fully automated hazing system reduces avian landings on a 45 acre defended pond by 97% Unpublished report to Region 6. Washington, DC: US Fish and Wildlife Service, USA.


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

Two controlled experiments at a 18.2 ha desulfurisation pond in north-central USA (Johansson et al. 1994) found that significantly fewer birds landed on ponds where a scaring system was in place (autumn and spring 1993-1994: 17 birds used a pond when the system was active for 48 hour periods vs. 125 when it was inactive for 48 hour periods; autumn 1994: 16 of 43,964 bird landings, 2% of the expected number, occurred on the pond with the system).  The radar-activated system (a BirdAvert© system) used various deterrents (broadcasts of recordings of e.g. dogs barking, guns firing and falcons screaming; strobe light; plastic falcons with flapping wings, and automated scarecrows).