Modelling risk of Blue Crane (Anthropoides paradiseus) collision with power lines in the Overberg region

[摘要] ENGLISH ABSTRACT: This study addresses the problem of Blue Crane (Anthropoides paradiseus) collisions withpower lines in the Overberg region, home to approximately 50% of South Africa's nationalbird's global population. The low visibility of power lines against the landscape is consideredto be the major cause of collisions. These claim at least 20 birds annually, which is aconsiderable loss to a vulnerable species.For this study, expert knowledge of the Blue Cranes' biology, general behaviour and use ofits habitat were compiled. These were then translated into rules that were integrated into aGeographic Information System (GIS) to establish a predictive model, which attempts toidentify and quantify risk power lines that Blue Cranes are most likely to collide with. Thecriteria that were considered included landscape proximity of power lines to water bodies aridcongregation sites, land cover, power lines orientation in relation to predominant winddirections (North Westerly and South Easterly) and visibility of the power lines against thelandscape.The power lines were ranked as highest, high, medium, low and no risk. It is recommendedthat this classification be used to prioritize the proactive marking of power lines with birdflappers in order to reduce collisions. The results show that 27% of the power lines in thestudy area pose the highest risk and should therefore be marked immediately. The powerlines classified as high (1%), medium (28%) and low risk (21 %) should be marked overshort, medium and long term, respectively ..The study demonstrated the potential of GIS in the conservation of Blue Crane. The GISmodel developed in this study can be applied in areas of similar habitat such as the Swartland or with some modifications in a slightly different habitat such as the Karoo. It is envisagedthat the results of this study will be of great value to the ESKOM (South African ElectricityCommission) and Endangered Wildlife Trust (EWT) Partnership and conservation authoritiesin the effort to save the Blue Crane.

[发布机构] Stellenbosch University