title: Determinants of emigration and their impact on survival during dispersal in fox and jackal populations.
abstract: Animals disperse in response to poor resource conditions as a strategy of escaping harsh competition and stress, but may also disperse under good resource conditions, as these provide better chances of surviving dispersal and gaining fitness benefits such as avoiding kin competition and inbreeding. Individual traits should mediate the effect of resources, yielding a complex condition-dependent dispersal response. We investigated how experimental food reductions in a food-rich environment around poultry-growing villages interact with individual-traits (age, gender, body-mass) in two sympatric canids, red foxes and golden jackals, to jointly affect emigration propensity and survival during dispersal. Sub-adult foxes emigrated more frequently from the food-rich habitat than from the pristine, food-limited habitat, while adult foxes showed the opposite trend. During dispersal, adults exhibited lower survival while sub-adults did not experience additional mortality costs. Although fox mortality rates increased in response to food reduction, dispersal remained unchanged, while jackals showed strong dispersal response in two of the three repetitions. Jackal survival under food reduction was lowest for the dispersing individuals. While resources are an important dispersal determinant, different age classes and species experience the same resource environment differently and consequently have different motivations, yielding different dispersal responses and consequences.
authors.affiliation: Mitrani Department of Desert Ecology, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
authors.forename: Dror
authors.initials: D
authors.lastname: Kapota
authors.affiliation: Science Division, Nature and Parks Authority, Jerusalem, Israel.
authors.forename: Amit
authors.initials: A
authors.lastname: Dolev
authors.affiliation: Centre for Ecosystem Science, School of Biological Earth and Environmental Sciences, University of New South Wales, Australia.
authors.forename: Gilad
authors.initials: G
authors.lastname: Bino
authors.affiliation: Society for protection of the nature, Tel Aviv, Israel.
authors.forename: Dotan
authors.initials: D
authors.lastname: Yosha
authors.affiliation: Society for protection of the nature, Tel Aviv, Israel.
authors.forename: Amichai
authors.initials: A
authors.lastname: Guter
authors.affiliation: Science Division, Nature and Parks Authority, Jerusalem, Israel.
authors.forename: Roni
authors.initials: R
authors.lastname: King
authors.affiliation: Mitrani Department of Desert Ecology, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Saltz
mesh_terms: D000375:Aging / Q000502:physiology; D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D017753:Ecosystem; D005247:Feeding Behavior; D005260:Female; D005589:Foxes / Q000502:physiology*; D046030:Jackals / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D011336:Probability; D016019:Survival Analysis