Empirical Evidence of Density‐Dependence in Populations of Large Herbivores

• Main Authors: Bonenfant, Christophe, Gaillard, Jean-Michel, Coulson, Tim, Festa-Bianchet, Marco, Loison, Anne, Garel, Mathieu, Loe, Leif Egil, Blanchard, Pierrick, Pettorelli, Nathalie, Owen-Smith, Norman, Du Toit, Johan, Duncan, Patrick
• Other Authors: Biodémographie évolutive, Département écologie évolutive LBBE, Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Division of Biology and Centre for Population Biology, Imperial College London, Département de biologie Sherbrooke (UdeS), Faculté des sciences Sherbrooke (UdeS), Université de Sherbrooke (UdeS)-Université de Sherbrooke (UdeS), Laboratoire d'Ecologie Alpine (LECA), Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences Oslo, Faculty of Mathematics and Natural Sciences Oslo, University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences Oslo, University of Oslo (UiO)-University of Oslo (UiO), Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institute of Zoology, Zoological Society of London, School of Animal, University of the Witwatersrand Johannesburg (WITS), Department of Forest, Utah State University (USU), Centre d'études biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2009
• Subjects: envir; demo; Arctic
• Online Access: https://doi.org/10.1016/S0065-2504(09)00405-X; https://hal.archives-ouvertes.fr/hal-00390498

International audience Density‐dependence is a key concept in population dynamics. Here, we review how body mass and demographic parameters vary with population density in large herbivores. The demographic parameters we consider are age‐ and sex‐specific reproduction, survival and dispersal. As population density increases, the body mass of large herbivores typically declines, affecting individual performance traits such as age of first reproduction and juvenile survival. We documented density‐dependent variations in reproductive rates for many species from the Arctic to subtropical zones, both with and without predation. At high density, a trade‐off between growth and reproduction delays the age of primiparity and often increases the costs of reproduction, decreasing both survival and future reproductive success of adult females. Density‐dependent preweaning juvenile survival occurs more often in polytocous than monotocous species, while the effects of density on post‐weaning juvenile survival are independent of litter size. Responses of adult survival to density are much less marked than for juvenile survival, and may be exaggerated by density‐dependent changes in age structure. The role of density‐dependent dispersal in population dynamics remains uncertain, because very few studies have examined it. For sexually dimorphic species, we found little support for higher sensitivity to increasing density in the life history traits of males compared to females, except for young age classes. It remains unclear whether males of dimorphic species are sensitive to male density, female density or a combination of both. Eberhardt's model predicting a sequential effect of density on demographic parameters (from juvenile survival to adult survival) was supported by 9 of 10 case studies. In addition, population density at birth can also lead to cohort effects, including a direct effect on juvenile survival and longterm effects on average cohort performance as adults. Density effects typically interact with weather, ...