Limited prospecting behaviour of juvenile Eagle OwlsBubo buboduring natal dispersal: implications for conservation

Abstract

Summary 24Capsule Breeding population and temporary settlement area features may reduce eagle owl 25Bubo bubo prospection for breeding sites during natal dispersal. 26 Aims Understand how low prospection rates may emerge during the dispersal process due to (i) 27 the main features of the breeding and dispersing portions of the population and (ii) main prey 28 availability. 29Methods We explored the 10-year dynamics and characteristics of radiotagged breeders and 30 dispersers of an Eagle Owl Bubo bubo population. 31 Results Lack of prospection during the first years after dispersal departures occurs in settlement 32areas where dispersers stop during dispersal (settlement areas are non-breeding zones located on 33 the border of the sector where live and reproduce the breeding population). Such areas could be 34 difficult to leave because not only is food abundant, but intraspecific competition and mortality 35 are low. We suggest that the lack of prospection during dispersal may reduce the willingness of 36 individuals to search for breeding sites and, thus, these dispersal settlement areas have the 37 potential to impact on the viability of breeding populations. 38Conclusion To prevent potential negative consequences at the population level due to this long 39 settlement of dispersers in their temporary settlement areas, this latter should be considered, 40 from a conservation point of view, as important as breeding areas. Reducing juvenile mortality 41 in settlement areas may represent an overlooked conservation strategy for long-lived species and 42 may have crucial effect on the viability of the reproductive sectors of an animal population. 43 3

Effects of rearing conditions on natal dispersal processes in a long‐lived predator bird

“…In fact, reducing juvenile mortality in dispersal areas is a crucial conservation strategy for long‐lived species and may have an important effect on the viability of the reproductive fraction of a population (Fasciolo et al., 2016; Hernández‐Matías et al., 2015). However, as these areas are often poorly known, difficult to detect and located in areas managed by more than one regional administration (each with their own particular jurisdictions), far less effort is generally devoted to their conservation than to breeding territories (Cadahía et al., 2010; Penteriani et al., 2015).…”

“…The study and assessment of dispersal areas in management and conservation are vital as such areas may be heavily affected by human disturbance and so may be excluded from typical management plans (Cadahía et al, 2010;Carrascal & Seoane, 2009;Penteriani & Delgado, 2009;Rollan, Hernández-Matías, & Real, 2016). In fact, reducing juvenile mortality in dispersal areas is a crucial conservation strategy for long-lived species and may have an important effect on the viability of the reproductive fraction of a population (Fasciolo et al, 2016;Hernández-Matías et al, 2015).…”

“…In this regard, recruitment age can be explained by two different hypotheses: the late‐breeding and the early‐breeding hypotheses. The former posits that individuals delay breeding until they acquire the competitive abilities and the familiarity with resources they require to obtain a breeding site in the natal environment (Fasciolo, del Mar Delgado, Cortés, Soutullo, & Penteriani, 2016; Penteriani & Delgado, 2009; Serrano, Tella, Donázar, & Pomarol, 2003); thus, birds in better condition are expected to recruit later because their prospects of future survival are higher in this learning period. On the contrary, the latter hypothesis (redefined according to Serrano et al., 2003) suggests that competitiveness may be innate and not driven by experience; thus, more competitive individuals recruit earlier into the breeding population than less competitive ones.…”

Roles of Raptors in a Changing World: From Flagships to Providers of Key Ecosystem Services

“…Nest site availability is one of the main limiting factors in urban areas and those that already exist are usually of poor quality (Altwegg et al, 2014). One of the consequences may be the establishment of long-term non-breeding territories, which would act as ecological traps (see Battin, 2004;Isaac et al, 2014;Fasciolo et al, 2016), ultimately reducing fitness components (Schlaepfer et al, 2002;Remes, 2003).…”