Foraging behaviour by gray wolves on salmon streams in coastal British Columbia

摘要: Spawning salmon (Oncorhynchus spp.) are important resources for terrestrial ecosystems and often shape the ecological strategies of organisms with which they co-evolve. Gray wolves (Canis lupus), primarily predators ungulates, sympatric over large areas, but relationship between two remains poorly understood. We report here observations direct indirect evidence predation by in several watersheds coastal British Columbia detail on foraging behaviour four at one river during September October 2001. Wolves oriented themselves upstream detection pursuit salmon. The pooled mean capture rate was 21.5 salmon/h efficiency (successes/attempt) 39.4%. In most cases, consumed only heads salmon, perhaps nutritional reasons or parasite avoidance. Preying may be adaptive, as this nutritious spatially constrained resource imposes lower risks injury compared hunting mammals. infer from rates efficiencies, well stereotypical feeding behaviour, a history and, corollary, broad distribution ecology where still co-exist. Resume : Les saumons en periode de fraye constituent d'importantes ressources pour l'ecosysteme terrestre et influencent souvent les ecologiques des organismes avec lesquels ils sont coevolution. loups gris avant tout predateurs d'ongules, vivent sympatrie sur grandes etendues, mais la relation entre deux reste mal comprise. Nous avons fait directes indirectes par dans plusieurs bassins hydrographiques region cotiere Colombie- Britannique nous decrivons ici details le comportement quete nourriture quatre une riviere, septembre octobre s'orientaient vers l'amont durant poursuite saumons. Le taux moyen capture, calcule l'ensemble resultats, etait 21,5 saumons/h l'efficacite moyenne (nombre tentatives reussies/total), 39,4 %. Dans plupart cas, ne consommaient que tete du saumon, peut-etre raisons nutritives ou eviter parasites. La peut etre adaptative, puisque cette ressource nutritive limitee l'espace est reliee risques reduits blessures comparativement aux ris - ques chasse gros mammiferes. Etant donne observes, meme comportements stereotypes prise nourriture, longue histoire, et, corollaire, l'ecologie se grande etendue coexistent.