In Canada, researchers tried owl decoys and predator calls near wind turbines; a pilot study found neither significantly deterred birds from the site

Wind turbines can pose collision risks to birds, prompting researchers to investigate ways to reduce wildlife interactions with turbine infrastructure. Among the proposed approaches are visual deterrents that resemble predators and audio recordings intended to warn birds of danger. However, these methods need to be tested under real-world conditions to determine whether they change bird behaviour and provide measurable protection.A 2019 pilot study by Dorey, Dickey and Walker tested whether an artificial owl and recorded predator and alarm calls could deter birds from the area around turbines at a wind farm in Nova Scotia, Canada. Its fieldwork took place in August and September 2016, and the authors reported no statistically significant deterrent effect on birds at the site compared with control sites.Researchers tested visual and audio deterrents in Nova ScotiaKatherine Dorey, Scott Dickey and Tony R. Walker published Testing Efficacy of Bird Deterrents at Wind Turbine Facilities: A Pilot Study in Nova Scotia, Canada, in the Proceedings of the Nova Scotian Institute of Science in 2019. The researchers tested two kinds of deterrents. The visual deterrent was a Bird-X Prowler Owl, an owl model with moving wings, perched within 50 metres of a turbine. The audio deterrent was playback of a Red-tailed Hawk call mixed with alarm calls from Ovenbirds and White-throated Sparrows, used to find out whether warning signals affect bird activity. The bird activity in the presence of the deterrents was compared with that in the absence of the deterrents. This comparison was essential since birds could vary their usage of the habitat due to factors not associated with the deterrents at all. The pilot study took place from 22 August to 16 September 2016 at a 5-turbine wind farm about 20 km northwest of Halifax. The authors compared four trial types: an owl model, the owl model plus predator and alarm call playback, a rotating control turbine, and a stationary control turbine. Across 12 sampling events, the authors note, low bird abundance and limited statistical power constrained the pilot.The findings did not establish a significant effectThere was no statistically significant decrease in the activity of the birds due to the use of the deterrents when compared to the control. Thus, the research did not confirm that the owl models or recordings prevented the birds from approaching the areas where the turbines were located. Such a conclusion should be taken into account properly. The lack of statistical significance does not mean that the deterrent cannot work. However, the experiment did not show that the deterrents were effective.The result also cannot show whether differently designed decoys, other sound recordings, or other combinations of the two would perform differently. Moreover, it is worth mentioning that the experiment did not confirm that the methods reduce the number of collisions and thus mortality of birds. Such changes are two different outcomes, and evidence of one of them cannot confirm the other. For wind farm operators the difference matters, because a deterrent can change where birds fly or how they behave near a turbine without reducing collisions or deaths.Wildlife protection requires stronger evidenceThe Nova Scotia studies are part of the larger problem in wind energy development of finding solutions to minimize any impact on wildlife while not assuming that because there is a feasible mechanism there is necessarily a benefit. The Canadian Impact Assessment Agency’s review, Strategies for Mitigating Impacts to Aerofauna from Offshore Wind Energy Development: Available Evidence and Data Gaps, examines a range of mitigation strategies for offshore wind development and identifies gaps in the available evidence. Further studies could investigate the effect that different decoys, sounds, playback times, and methods have on the birds. The studies should consider the differences in species and locations, because what works for one species at one location may not work for another.The researchers should differentiate between changes in behavior that occur in the short term and outcomes that actually make a difference in terms of bird protection. Extended observation times and well-designed experiments could determine whether the changes are long-lasting and result in effective protection. The Nova Scotia pilot project does not show that all bird deterrents are ineffective. It shows only that the tested owl decoys and owl sounds did not produce a statistically significant change in bird activity.You use AI every day. Now get your AI Quotient. Take the AIQ test.