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Free food for everyone: artificial feeding of brown bears provides food for many non-target species

  • Urša Fležar
  • Beatriz Costa
  • Dejan Bordjan
  • Klemen Jerina
  • Miha Krofel
Original Article

Abstract

Artificial feeding of wildlife is a widely used tool for a range of conservation and management goals. While the effects of artificial feeding on target species have been studied rather extensively, little is known about its effects on non-target species. We used automatic video surveillance to monitor the vertebrate species using artificial feeding sites (n = 20) established primarily for brown bears (Ursus arctos) in Dinaric Mountains, Slovenia. We also studied how type of artificial food (only plant-based food vs. mixed food including carrion) affects the species diversity and assemblage at the feeding sites. In total, we analyzed 117,566 recordings and identified 23 vertebrate taxa, including the brown bear, using the feeding sites. Brown bear, European badger (Meles meles), and red fox (Vulpes vulpes) were the most frequently recorded species. Birds represented a substantial part (46%) of vertebrate community using the feeding sites, including species of a high conservation importance. Feeding sites were regularly used also by species for which intentional artificial feeding is forbidden in study area (e.g., roe deer Capreolus capreolus). Species diversity at the feeding sites was highest in spring while species composition varied both seasonally and according to the type of artificial food (with or without carrion). Our study indicates that artificial feeding affects numerous non-target species, which could have several ecological and management-relevant effects, including potentially undesired consequences. Artificial feeding of wildlife should be carefully planned and we provide recommendations on how to mitigate the side effects on non-target species.

Keywords

Anthropogenic food Wildlife feeding Non-target species Brown bear Ursus arctos Camera traps 

Notes

Acknowledgements

We would like to thank hunters from the Slovenia Forest Service and the Slovenian Hunting Association for their substantial help with the field work. Special thanks to M. Mohorović for her help in establishing the monitoring program and coordinating the activities of camera trapping. Many thanks to all the students that have helped process the photos from camera traps: R. Ule, M. Gagliardi, A. Jerina, L. Gal, F. Feurstein, G. Marolt, L. Stopar, L. Hočevar, and M. Predalič. We are grateful to A. Žagar for database maintenance, R. Luštrik for many useful tips on data organization, M. de Groot for his generous help with the data analysis, and E. Ferreira for useful comments on the early draft.

Funding information

Funding for the study was provided by the European LIFE mechanism within the LIFE DINALP BEAR project (LIFE13 NAT/SI/000550). B.C. was supported by Unidade de Vida Selvagem. K.J. and M.K. were additionally supported by the Slovenian Research Agency (J4-7362, P4-0059).

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Urša Fležar
    • 1
  • Beatriz Costa
    • 1
    • 2
  • Dejan Bordjan
    • 1
  • Klemen Jerina
    • 1
  • Miha Krofel
    • 1
  1. 1.Department of Forestry and Renewable Forest Resources, Biotechnical FacultyUniversity of LjubljanaLjubljanaSlovenia
  2. 2.Department of Biology, Centre for Environmental and Marine StudiesUniversity of AveiroAveiroPortugal

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