Top Scavengers in a Wilder Europe

Abstract

The concept of rewilding should not only be applied to recovering habitat and vertebrate populations but also to the restoration of complex ecological processes. Large avian scavengers are the target of restoration programs including conservation measures linked to the manipulation of food resources but we lack of a general approach to understanding how scavengers and the ecosystem services they provide will fit into a rewilded Europe. Carcasses play an important role in ecosystem functioning and in the energy flux within food webs. Large ungulates carcases availability, in particular, has, through the course of evolution, given way to the appearance of "true" scavenger strategies, displayed by large body-sized avian organisms (vultures) whose guilds are structured by complex interspecific relationships. Yet, livestock raised in traditional agro-grazing systems have historically replaced wild ungulates as the main food source for vultures. More recently, modern farm intensification, stricter European Union legislation that banned the abandonment of carcasses, and increasing human-vulture conflicts contributed to plunging vulture populations, leading to an unprecedented crisis. Consequently, supplementary feeding became a management tool used worldwide to aid in the recovery of their decimated populations. These so-called vulture restaurants,

How to fit the distribution of apex scavengers into land‐abandonment scenarios? The Cinereous vulture in the Mediterranean biome

“…In fact, the Cinereous vulture depends heavily on lagomorphs (3%–60% of diet, Hiraldo, ; Corbacho et al., ), a pattern also found in the rest of their distribution area where the diet is based on small‐sized and medium‐sized prey (rodents) typical of open landscapes such as natural and semi‐natural steppes (Dobado & Arenas, and reviews therein). In this scenario, and as was stated above, farmland abandonment and the subsequent ecological succession would negatively affect European wild rabbit abundances (Cortés‐Avizanda et al., ).…”

“…At the end, however, the viability of populations of large body‐sized mammals (ungulates and carnivores) will be strongly dependent of the interactions with humans and of how potential conflicts are solved (Bisi, Kurki, Svensberg, & Liukkonen, ). In fact, these conflicts, notably predation of carnivores on livestock, may lead to indirect persecution of vultures by poisoning which has virtually extirpate entire populations on large parts of the Mediterranean Europe during the last centuries (Bijleveld, ; Donázar et al., 2009, Cortés‐Avizanda et al., ).…”

“…Foraging habitat is, on its part, mostly limited by the availability of wild prey (ungulates and wild rabbits). Presumably, land abandonment and the ecological succession resulting there from (i.e., pasture to scrubland or scrubland to forest) would reduce the abundance of the European wild rabbit due to the disappearance of mosaics of pastures, crops and scrubs which provide high‐quality resources and refuge against predators (Cortés‐Avizanda et al., and references therein). On this basis, we focused on the evaluation of how the land‐abandonment processes can change the habitats of the Cinereous vultures.…”

“…We examine here how the spatial distribution of an apex scavenger may be affected by different socioeconomic scenarios including macroeconomic projections at global scale and land use models that translate these changes into spatial patterns of land abandonment at the European scale (Stürck et al., ). Vultures have a millenary link with human agro‐grazing systems (Donázar, Naveso, Tella, & Campión, ; Moreno‐Opo, Arredondo, & Guil, ) with well‐recognized roles as providers of regulatory and cultural ecosystem services (Cortés‐Avizanda, Donázar, & Pereira, ; DeVault et al., ; Haines‐Young & Potschin, ; Maes, Teller, Erhard, Liquete, & Braat, ). We took the Cinereous vulture ( Aegypius monachus ) as our study model because this species is known to be closely linked to the traditional agro‐grazing systems in Mediterranean landscapes.…”

Rewilding processes shape the use of Mediterranean landscapes by an avian top scavenger

“…The generalised land abandonment and concomitant rewilding process predicted for the next few decades present a new scenario for vulture conservation 17 . If the regeneration of natural vegetation is accompanied by the recovery of wild ungulates, vultures could benefit from this resource, compensating for the shortage of domestic livestock.…”