TY  - JOUR
A1  - Schaub, Tonio
A1  - Klaassen, Raymond H. G.
A1  - Bouten, Willem
A1  - Schlaich, Almut E.
A1  - Koks, Ben J.
T1  - Collision risk of Montagu’s Harriers Circus pygargus with wind turbines derived from high-resolution GPS tracking
JF  - Ibis : the international journal of avian science ; the journal of the British Ornithologists' Union
N2  - Flight behaviour characteristics such as flight altitude and avoidance behaviour determine the species-specific collision risk of birds with wind turbines. However, traditional observational methods exhibit limited positional accuracy. High-resolution GPS telemetry represents a promising method to overcome this drawback. In this study, we used three-dimensional GPS tracking data including high-accuracy tracks recorded at 3-s intervals to investigate the collision risk of breeding male Montagu's Harriers Circus pygargus in the Dutch–German border region. Avoidance of wind turbines was quantified by a novel approach comparing observed flights to a null model of random flight behaviour. On average, Montagu's Harriers spent as much as 8.2 h per day in flight. Most flights were at low altitude, with only 7.1% within the average rotor height range (RHR; 45–125 m). Montagu's Harriers showed significant avoidance behaviour, approaching turbines less often than expected, particularly when flying within the RHR (avoidance rate of 93.5%). For the present state, with wind farms situated on the fringes of the regional nesting range, collision risk models based on our new insights on flight behaviour indicated 0.6–2.0 yearly collisions of adult males (as compared with a population size of c. 40 pairs). However, the erection of a new wind farm inside the core breeding area could markedly increase mortality (up to 9.7 yearly collisions). If repowering of the wind farms was carried out using low-reaching modern turbines (RHR 36–150 m), mortality would more than double, whereas it would stay approximately constant if higher turbines (RHR 86–200 m) were used. Our study demonstrates the great potential of high-resolution GPS tracking for collision risk assessments. The resulting information on collision-related flight behaviour allows for performing detailed scenario analyses on wind farm siting and turbine design, in contrast to current environmental assessment practices. With regard to Montagu's Harriers, we conclude that although the deployment of higher wind turbines represents an opportunity to reduce collision risk for this species, precluding wind energy developments in core breeding areas remains the most important mitigation measure.
KW  - avoidance rate
KW  - environmental impact
KW  - flight height
KW  - human-wildlife conflict
KW  - mitigation
KW  - raptors
KW  - renewable energy
KW  - wind energy
Y1  - 2019
U6  - https://doi.org/10.1111/ibi.12788
SN  - 0019-1019
SN  - 1474-919X
VL  - 162
IS  - 2
SP  - 520
EP  - 534
PB  - Wiley
CY  - Hoboken
ER  -