Simulating the Success of Trail Closure Strategies on Reducing Human Disturbance to Nesting Golden Eagles
As nature-based recreation grows in popularity, there is concern for reduced fitness of animals exposed to chronic disturbance by these activities. Golden Eagles (Aquila chrysaetos) and other raptors are sensitive to human recreation near their nests, and managers of these species need strategies to mitigate negative effects. We used simulation models to separate the effects of trail density and configuration, land cover configuration, and volume of human recreation on the effectiveness of 2 trail closure strategies to manage disturbance. We simulated a breeding pair of Golden Eagles at 3 territories with varying degrees of trail density under current and increased levels of human activity. We simulated a baseline scenario, a scenario with a 600 m restrictive buffer around the nest, and a scenario where we closed all but the most popular trails to human recreation. We also conducted a trail-swapping simulation with trail configurations of each territory placed into the land cover of the other territories under current and increased levels of human recreation. This allowed us to isolate the effects of trail density and configuration from land cover configuration on flushing frequency of eagles. We found that for current levels of human recreation, the restrictive buffer was best at reducing flushing of incubating eagles, while closing all but the popular trails was best for foraging eagles. However, management did not mitigate disturbance for trail-swapping simulations, indicating that trail density was the main factor influencing eagle flushing frequency when human recreation was increased. Our results suggest that managers should consider both trail density and the level of human recreation before deciding on mitigation strategies, as approaches that work at lower human activity levels may be ineffective when activity levels increase.
D'Acunto, Laura E.; Spaul, Robert J.; Heath, Julie A.; and Zollner, Patrick A.. (2018). "Simulating the Success of Trail Closure Strategies on Reducing Human Disturbance to Nesting Golden Eagles". The Condor: Ornithological Applications, 120(3), 703-718. http://dx.doi.org/10.1650/CONDOR-17-223.1