Larger size and older age confer competitive advantage: dominance hierarchy within European vulture guild

Abstract

competition for limiting natural resources generates complex networks of relationships between individuals, both at the intra-and interspecific levels, establishing hierarchical scenarios among different population groups. Within obligate scavengers, and especially in vultures, the coevolutionary mechanisms operating during carrion exploitation are highly specialized and determined in part by agonistic behavior resulting in intra-guild hierarchies. This paper revisits the behavioral and hierarchical organization within the guild of European vultures, on the basis of their agonistic activities during carrion exploitation. We used a dataset distilled from high-quality videorecordings of competitive interactions among the four European vulture species during feeding events. We found a despotic dominance gradient from the larger species to smaller ones, and from the adults to subadults and juveniles, following an age and body size-based linear pattern. The four studied species, and to some extent age classes, show despotic dominance and organization of their guild exerting differential selection to different parts of the carrion. The abundance of these parts could ultimately condition the level of agonistic interactions. We discuss the behavioral organization and the relationship of hierarchies according to the feeding behavior and prey selection, by comparing with other scavenger guilds.Competition for naturally limited resources generates complex networks of relationships between individuals, based on evolutionary, morphological and behavioral adaptations of different species and populations 1,2 . These competitive relationships at the intra-and interspecific levels may result in: (1) the establishment of dominance hierarchies between competing groups disputing a particular resource 3,4 ; (2) resource partitioning, both in the means of obtaining the disputed resource and in resource selection 5 ; and (3) differing energetic efficiencies obtained from different parts of a shared resource 6,7 .In obligate scavenging animals, the coevolutionary behavioral mechanisms established within this guild are highly specialized in both competitive and facilitatory aspects 4,8-11 . This particular specialization in feeding demeanor is a result of the type of resource being exploited. Carrion is a pulsed food source which is unpredictable and usually limited in occurrence in space and time, which offers highly nutritive biomass [12][13][14][15] . In addition to ecomorphological adaptations (i.e. robust beaks, head without long feathers, accurate visual ability, digestive tracts tolerant to potential pathogens in carrion), obligate scavengers have developed behavioral adaptations to optimize carrion exploitation [16][17][18] , including various agonistic behaviors. Individuals exhibit aggressive activities to exclude competitors (con-or heterospecific) from disputed resources 19 . Such aggressive behaviors are common in many animal species 20 , although they are especially vigorous in terms of display and duration in predators and...

Molecular diversity of Extended‐spectrum β‐lactamase‐producing Escherichia coli from vultures in Canary Islands

“…coli in the faecal microbiota of healthy vultures, and most of the studies have focused on E . coli isolates from domestic animals (Stolle et al ., 2013; Ewers et al ., 2014; Marques et al ., 2016; Pulss et al ., 2018) or in wild birds or vultures only from Spanish peninsula (Alcala et al ., 2016; Lopez‐Cerero et al ., 2017; Moreno‐Opo et al ., 2020). To our knowledge, this is the first study on the genetic background in commensal E .…”

“…The Iberian Peninsula holds >90% of the European population of wild vultures (Lopez‐Cerero et al ., 2017). The Egyptian vultures ( Neophron percnopterus ) are the smallest and least dominant of the European vultures (Moreno‐Opo et al ., 2020). Until a few decades ago, the wild Canarian Egyptian vulture ( Neophron percnopterus var .…”

“…coli done in Canarian Egyptian vultures. Even though antibiotic resistance in vultures has been less studied than in other domestic animals worldwide (Ahmed et al ., 2010; Tuerena et al ., 2016; Carvalho et al ., 2017; Saputra et al ., 2017; Rumi et al ., 2019; Suay‐Garcia et al ., 2019), there are some recent available data in different Spanish cities that suggest that Neophron percnopterus might have an important role in the spread of ESBL/pAmpC bacteria (Alcala et al ., 2016; Lopez‐Cerero et al ., 2017; Moreno‐Opo et al ., 2020; Sevilla et al ., 2020). In this way, contact with urban waste and livestock farming has been associated with increased probability of antibiotic‐resistant microbiota in wild birds, especially ESBL‐producing E .…”

New Zealand's extinct giant raptor (Hieraaetus moorei) killed like an eagle, ate like a condor

“…monachus as a ripper of flesh that favours the tough skin and meat of large mammal carcasses [4], possibly with strong lateral forces as well as powerful biting. Aegypius monachus is a large and aggressive vulture that dominates other avian scavengers when fights occur over a carcass [40,41]. By contrast, Vul.…”

Anthropogenic Drivers Leading to Population Decline and Genetic Preservation of the Eurasian Griffon Vulture (Gyps fulvus)

“…Among the morphological and biological characters interpretable as adaptations are bare heads and neck to avoid pollution of feathers when feeding inside carcasses, strong hooked beaks with cutting edges to tear skin apart and feet more appropriate for movement on the ground than to catch prey [16]. A further adaptation is related to the feeding behaviour resulting in complex relationships at both intraspecific and interspecific levels during carcass exploitation [22][23][24][25]. The species of both families developed a static soaring style, perfectly optimised for searching for food over wide areas minimising the energy expenditure.…”