Beyond BACI: Offsetting carcass numbers with flight intensity to improve risk assessments of bird collisions with power lines

Ecology and Evolution

Klaus Jödicke¹  Moritz Mercker² 

[1] Biologen im Arbeitsverbund (B.i.A.) Bordesholm Germany;Bionum GmbH –Consultants in Biological Statistics Hamburg Germany;

关键词: BACI;    bird collision;    bird flight;    bird strike;    collision rate;    experimental design;   

DOI  :  10.1002/ece3.8291

来源: DOAJ

【 摘 要 】

Abstract The continuing global expansion of electricity networks increases the risk of bird collisions with power lines. Several field studies have demonstrated that this risk can be reduced by marking lines with flight diverters. A before‐after control‐impact (BACI) design is currently the suggested approach for evaluating the effectiveness of these diverters and is generally assumed to give unbiased results. Using systematic flight survey data, we demonstrate that the assumptions underlying the BACI approach are frequently violated, leading to biased effectiveness estimates. We present an alternative field and statistical design in which the number of bird strike victims is directly related to bird flight intensity (“fusion design”), instead of estimating it indirectly using a control site. The presented design is validated based on simulations. We demonstrate that the presented method is unbiased and shows an approximately 3‐fold higher statistical power compared with BACI, even under ideal/unbiased data conditions, with similar field‐experimental effort. Moreover, this approach can provide a direct analysis of bird reactions/collisions, estimation of collision rates, and the possibility of conducting the required fieldwork within a single season. Our presented method can be used to standardize and improve future studies on diverter effectiveness, for example, by supporting the acquisition of a more detailed picture of species‐, diverter type‐, and habitat‐specific estimates.

【 授权许可】

Unknown