White Stork FID

Human activities often negatively affect the time birds spend on parental care, foraging and resting. However, some species can adapt to human disturbances by increasing their fitness in that they exploit human‐induced resources, but this involves forms of antipredator behaviour such as vigilance. We studied the flight initiation distance (FID) of White Storks Ciconia ciconia foraging on hay meadows during their breeding season. The GLM model showed that farm work taking place, the type of meadows and starting distance (the distance from the bird at the start of the walk) all had an influence on FID. Conversely, the numbers of storks in a particular foraging flock had no effect on an individual bird’s FID. The reduction in FID could be due to the presence of machinery operating in the meadows, because the storks then have opportunities to catch energy-rich prey that has been scared off by the machines. Unlike meadows cleared of hay, mown meadows with cut grass are more attractive to storks, and the FID is shorter. The observer starting distance negatively affected stork escape responses. These findings suggest that the FID of White Storks, treated as a measure of the risk of predation, depends largely on the degree of attractiveness of the feeding ground.