Titre du document / Document title

Common ravens, Corvus corax, preferentially associate with grey wolves, Canis lupus, as a foraging strategy in winter

Auteur(s) / Author(s)

STAHLER Daniel ^{(1 2)} ; HEINRICH Bernd ⁽¹⁾ ; SMITH Douglas ⁽²⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Department of Biology, University of Vermont, ETATS-UNIS
⁽²⁾ Yellowstone Center for Resources, Yellowstone National Park, ETATS-UNIS

Résumé / Abstract

One foraging strategy that scavengers can employ to discover unpredictable food sources is to associate directly with predators who inadvertently provide food. The common raven, a well known feeding generalist, is also a prominent scavenger of wolves' kills and is found to be in close association with this predator. We tested the hypothesis that ravens preferentially associate with wolves in winter as a kleptoparasitic foraging strategy. The presence, absence and behaviour of ravens was documented during winter observations of wolves, coyotes, Canis latrans, and elk, Cervus elaphus, as well as the landscape in the absence of these three species. Ravens were found to be in close association with wolves when they were travelling, resting and hunting prey. In comparison, ravens showed no significant association with coyotes, elk or areas on the landscape in the absence of wolves. We also compared ravens' discovery success of wolf-killed and nonwolf-killed carcasses and their behavioural response upon discovery. Ravens found all wolf kills almost immediately and remained at the carcass to feed alongside wolves after the death of the prey. In contrast, ravens were less successful discovering experimentally placed carcasses in the same study region, and did not land or feed despite the availability of fresh, exposed meat. Our results show that ravens' association with wolves is not just an incidental and proximate by-product of the presence of fresh meat. Instead, we show that ravens preferentially associate with wolves in both the presence and absence of food, resulting in the discovery of carcasses and suppression of ravens' innate fear of novel food sources. Through this mode of social foraging, ravens may experience increased foraging efficiency in the use of an otherwise spatially and temporally unpredictable food source.

Revue / Journal Title

Animal behaviour   ISSN 0003-3472   CODEN ANBEA8 

Source / Source

2002, vol. 64 (2), pp. 283-290 [8 page(s) (article)] (49 ref.)

Langue / Language

Anglais

Editeur / Publisher

Elsevier, Kent, ROYAUME-UNI  (1958) (Revue)

Mots-clés anglais / English Keywords

Vertebrata ; Aves ; America ; North America ; Feeding behavior ; Corvus corax ; United States ; Field study ; Predator prey relation ; Resource ; Availability ; Kleptoparasitism ; Interspecific relation ; Foraging behavior ;

Mots-clés français / French Keywords

Vertebrata ; Aves ; Amérique ; Amérique du Nord ; Comportement alimentaire ; Corvidae ; Corvus corax ; Etats Unis ; Etude sur terrain ; Relation prédateur proie ; Ressource ; Disponibilité ; Kleptoparasitisme ; Relation interspécifique ; Comportement approvisionnement ;

Mots-clés espagnols / Spanish Keywords

Vertebrata ; Aves ; America ; America del norte ; Conducta alimenticia ; Corvus corax ; Estados Unidos ; Estudio en campo ; Relación depredador presa ; Recurso ; Disponibilidad ; Cleptoparasitismo ; Relación interespecífica ; Conducta abastecimiento ;

Localisation / Location

INIST-CNRS, Cote INIST : 7067, 35400010663087.0150