Data on Bird Mortality in "Sakar" IBA (BG021), Caused by Hazardous Power Lines

Bird mortality caused by 20 kV power lines was studied in “Sakar” Important Bird Area (IBA). In the period between February 2008 - April 2009, six power lines with a total length of 44,6 km and 450 electric poles of different design were monitored once a month. Forty-four victims belonging to 21 taxa, including representatives of 8 orders, were recorded. Suspected collisions represented 34,09% (n=15) of all dead birds found under the lines. Most of the victims were small songbirds (26%). Suspected victims of electrocution represented 65,91% (n=29) of the recorded carcasses. Electric poles of type 1 (p=0,189) ? metal tower with jumper wires, proved to be the most dangerous design, followed by type 2 (p=0,067) - concrete poles with pin-type insulators. The monitored power lines ran across four main habitat types: arable lands, vineyards and orchards, forests (Quercus sp., Pinus sp.), and open grasslands (pastures and uncultivated lands). Most of the suspected collisions were found in arable lands (60%) and open grasslands. Electrocution was suspected mainly for birds in open grass habitats (0,078 victim/pole), vineyards (0,062 victim/pole), and arable lands (0,054 victim/pole). No victims of electrocution were found in the forests.