Limited prospecting behaviour of juvenile Eagle Owls Bubo bubo during natal dispersal: implications for conservation

Capsule Features of the breeding population and temporary settlement area influence the behaviour of Eagle Owls Bubo bubo prospecting for breeding sites during natal dispersal.

Aims To understand how prospecting behaviour during natal dispersal is affected by (i) the main characteristics of the breeding and dispersing portions of the population and (ii) main prey availability.

Methods We explored the ten-year dynamics and characteristics of radio-tagged breeders and dispersers of an Eagle Owl population.

Results During the first years following natal dispersal there was little prospecting behaviour of nesting sites and birds remained mainly within non-breeding settlement areas, bordering the sector occupied by the breeding population. Settlement areas had an abundant food supply, and low intraspecific competition and mortality. We suggest that these features of the settlement areas may reduce the willingness of individuals to search for breeding sites and may have the potential to impact on the viability of breeding populations.

Conclusion From a conservation perspective, the lengthy use of the temporary settlement areas by juvenile Eagle Owls suggests that the sites should be considered as important as the breeding areas when planning conservation strategies. Reducing juvenile mortality in settlement areas may represent an overlooked conservation strategy for long-lived species and may have a crucial effect on the viability some animal populations.