Individual consistency in flight initiation distances in burrowing owls: a new hypothesis on disturbance-induced habitat selection.

Individuals often consistently differ in personalities and behaviours that allow them to cope with environmental variation. Flight initiation distance (FID) has been measured in a variety of taxa as an estimate of the risk that an individual is willing to take when facing a predator. FID has been used to test life-history trade-offs related to anti-predatory behaviour and for conservation purposes such as to establish buffer zones to minimize human disturbance, given its species-specific consistency. Individual consistency in FID, however, has been largely overlooked. Here we show that, even after controlling for several confounding effects, this behaviour has a strong individual component (repeatability = 0.84-0.92) in a bird species, leaving a small margin for behavioural flexibility. We hypothesize that individuals may distribute themselves among breeding sites depending on their individual susceptibility to human disturbance. This habitat selection hypothesis merits further research, given its implications on both evolutionary and applied ecology research. For example, selection of human-tolerant phenotypes may be promoted through the humanization of habitats occurring worldwide, and when population means instead of individual variability in FID are considered for designing buffer zones to reduce human impacts on wildlife.