Regulated hunting re-shapes the life history of brown bears

  • Nature Ecology & Evolutionvolume 2pages116123 (2018)
  • doi:10.1038/s41559-017-0400-7
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Management of large carnivores is among the most controversial topics in natural resource administration. Regulated hunting is a centrepiece of many carnivore management programmes and, although a number of hunting effects on population dynamics, body-size distributions and life history in other wildlife have been observed, its effects on life history and demography of large carnivores remain poorly documented. We report results from a 30-year study of brown bears (Ursus arctos) analysed using an integrated hierarchical approach. Our study revealed that regulated hunting has severely disrupted the interplay between age-specific survival and environmental factors, altered the consequences of reproductive strategies, and changed reproductive values and life expectancy in a population of the world’s largest terrestrial carnivore. Protection and sustainable management have led to numerical recovery of several populations of large carnivores, but managers and policymakers should be aware of the extent to which regulated hunting may be influencing vital rates, thereby reshaping the life history of apex predators.

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We are grateful for the support of the Center for Advanced Study in Oslo, Norway, that funded and hosted our research project ‘Climate effects on harvested large mammal populations’ during the academic year of 2015–2016. R.B. and J.S. received additional funding from the Polish-Norwegian Research Program (GLOBE No POL-NOR/198352/85/2013). This research was supported in part by the computing cluster of the Pôle Bioinformatique Lyonnais. We thank S. Frank and A. Hertel for preparation of select environmental data, A. Ordiz, J. Kindberg, and V. Vazquez for constructive comments on the manuscript, and the Swedish Association for Hunting and Wildlife Management for the Large Carnivore Observation Index (LCOI), which was used to derive the density index. This is scientific paper 244 of the Scandinavian Brown Bear Research Project.

Author information


  1. Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway

    • Richard Bischof
    • , Andrea Friebe
    •  & Jon E. Swenson
  2. Université de Lyon, F-69000, CNRS, UMR, 5558, Laboratoire de Biométrie et Biologie Évolutive, Villeurbanne, France

    • Christophe Bonenfant
  3. Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway

    • Inger Maren Rivrud
    •  & Atle Mysterud
  4. Department of Natural Sciences and Environmental Health, University College of Southeast Norway, Bø, Norway

    • Andreas Zedrosser
  5. Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, Vienna, Austria

    • Andreas Zedrosser
  6. Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK

    • Tim Coulson
  7. Norwegian Institute for Nature Research, Trondheim, Norway

    • Jon E. Swenson


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R.B. and C.B. conceived the study with J.E.S., A.M. and T.C. J.E.S., A.Z. and A.F. coordinated collection and compilation of field data. R.B., I.M.R. and A.Z. extracted and formatted intrinsic and extrinsic covariates. R.B. and C.B. developed, implemented and analysed the model. R.B. wrote the first draft of the paper; all authors contributed to subsequent versions.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Richard Bischof.

Electronic supplementary material

  1. Supplementary Information

    Supplementary Figures 1–3, Supplementary Tables 1–9; Supplementary reference; description of Supplementary data files

  2. Life Sciences Reporting Summary

  3. Supplementary Data Set 1

    Data for Figure 1

  4. Supplementary Data Set 2

    Data for Figure 3

  5. Supplementary Data Set 3

    Data for Figure 4

  6. Supplementary Data Set 4

    Multistate model for JAGS

  7. Supplementary Data Set 5

    Data for Supplementary Figure 2

  8. Supplementary Data Set 6

    Data for Supplementary Figure 3