Predator‐prey feedback in a gyrfalcon‐ptarmigan system?

Specialist predators with oscillating dynamics are often strongly affected by the population dynamics of their prey, yet they are not always the cause of prey cycling. Only those that exert strong (delayed) regulation of their prey can be. Inferring predator–prey coupling from time series therefore requires contrasting models with top‐down versus bottom‐up predator–prey dynamics. We study here the joint dynamics of population densities of the...