Territorial defense by coyotes (<i>Canis latrans</i>) in Yellowstone National Park, Wyoming: who, how, where, when, and why

Abstract

Territorial defense and maintenance are an important facet of the social ecology of most carnivore species. From January 1991 to June 1993, we observed 54 coyotes (Canis latrans) for 2507 h in Yellowstone National Park, Wyoming, during which we observed 112 instances of territory defense. The identity of the coyotes involved in challenging and evicting intruding animals was known. Alpha coyotes were most likely to be involved in territorial evictions of intruding animals, followed by beta individuals; pups participated little in territory defense. Coyotes evicting intruders generally had a numerical advantage when challenging the intruders. Territory-defense rates were highest during and immediately after the breeding season and during the time of pup emergence from the den. All chases of intruders ended at the boundary of the resident coyote pack's territory. Physical contact between the intruding animal and resident pack members occurred with no intruders being killed or seriously injured. Physical contact consisted of fighting and ritualized behaviors, with only a few instances in which fighting led to blood being drawn or minor injuries to the intruder. Most encounters resulted in a hasty retreat from the area by the intruder(s). While indirect means of territory maintenance (i.e., howling and scent-marking) were utilized by resident packs, trespassing still occurred and direct confrontation was needed to enforce boundaries and assert occupancy against other resident packs, as well as against lone intruders seeking territory vacancies. Territoriality was advantageous in that territory holders generally had higher survival rates (except pups), contributed all the reproductive effort to the population, and had greater access to food resources. In contrast, nonterritorial animals had lower survival rates, did not breed, and had reduced access to food (ungulate carcasses) during winter.Résumé : La défense et la conservation du territoire constituent une facette importante de l'écologie sociale de la plupart des espèces de carnivores. De janvier 1991 à juin 1993, nous avons observé 54 coyotes (Canis latrans) pendant 2507 h dans le parc national de Yellowstone, au Wyoming, au cours desquelles nous avons étudié 112 cas de défense de territoire. Les coyotes qui ont défié et chassé des intrus de leur territoire ont été identifiés. Les coyotes alpha sont plus enclins à évincer les intrus de leur territoire, suivis des coyotes bêta; les petits participent peu à la défense territoriale. Les coyotes qui évincent des intrus ont généralement l'avantage numérique lorsqu'ils les poursuivent. La fré-quence des cas de défense territoriale est maximale pendant et immédiatement après la saison de reproduction et au moment de la sortie des petits des terriers. Toutes les poursuites observées ont pris fin à la frontière du territoire de la meute résidante. Les contacts physiques entre intrus et résidants de la meute n'ont jamais abouti à la mort d'un intrus, ni même à des blessures graves. Les contacts physiques se limit...

The nasty neighbour in the striped mouse (Rhabdomys pumilio) steals paternity and elicits aggression

“…Here we showed that male breeders are more aggressive than male philopatrics that typically do not breed within their group (for a similar result in coyotes see [3]), though they might seek copulations with females from neighbouring groups. Additionally, breeding males were more aggressive towards strangers during the breeding season than during the non-breeding season.…”

“…The importance of territoriality in obtaining reproductive success has been demonstrated for example in coyotes ( Canis latrans ) where reproductive success within a population was obtained exclusively by territorial individuals [3]. While territoriality can have significant benefits, it is also costly [4], especially in forms of energy expenditure [5], time requirements and the increased risk of injury [6] and predation [1].…”

Olfactory attractants and parity affect prenatal androgens and territoriality of coyote breeding pairs

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