Nature vs. Nurture: Evidence for Social Learning of Conflict Behaviour in Grizzly Bears

PLoS One. 2016 Nov 16;11(11):e0165425. doi: 10.1371/journal.pone.0165425. eCollection 2016.

Abstract

The propensity for a grizzly bear to develop conflict behaviours might be a result of social learning between mothers and cubs, genetic inheritance, or both learning and inheritance. Using non-invasive genetic sampling, we collected grizzly bear hair samples during 2011-2014 across southwestern Alberta, Canada. We targeted private agricultural lands for hair samples at grizzly bear incident sites, defining an incident as an occurrence in which the grizzly bear caused property damage, obtained anthropogenic food, or killed or attempted to kill livestock or pets. We genotyped 213 unique grizzly bears (118 M, 95 F) at 24 microsatellite loci, plus the amelogenin marker for sex. We used the program COLONY to assign parentage. We evaluated 76 mother-offspring relationships and 119 father-offspring relationships. We compared the frequency of problem and non-problem offspring from problem and non-problem parents, excluding dependent offspring from our analysis. Our results support the social learning hypothesis, but not the genetic inheritance hypothesis. Offspring of problem mothers are more likely to be involved in conflict behaviours, while offspring from non-problem mothers are not likely to be involved in incidents or human-bear conflicts themselves (Barnard's test, p = 0.05, 62.5% of offspring from problem mothers were problem bears). There was no evidence that offspring are more likely to be involved in conflict behaviour if their fathers had been problem bears (Barnard's test, p = 0.92, 29.6% of offspring from problem fathers were problem bears). For the mother-offspring relationships evaluated, 30.3% of offspring were identified as problem bears independent of their mother's conflict status. Similarly, 28.6% of offspring were identified as problem bears independent of their father's conflict status. Proactive mitigation to prevent female bears from becoming problem individuals likely will help prevent the perpetuation of conflicts through social learning.

MeSH terms

  • Alberta
  • Animals
  • Behavior, Animal / physiology*
  • Conflict, Psychological
  • Female
  • Geography
  • Male
  • Nature*
  • Social Learning / physiology*
  • Ursidae / physiology*

Grants and funding

This study was funded by the organizations listed below, including: Alberta Conservation Association Grants in Biodiversity: http://www.ab-conservation.com/go/default/index.cfm/grants/grant-eligible-conservation-fund/overview/; Alberta Ecotrust: http://albertaecotrust.com/; Alberta Environment and Parks: http://aep.alberta.ca/; Alberta Innovates – Bio Solutions: http://bio.albertainnovates.ca/; Alberta Sport Recreation Parks and Wildlife Foundation; Disney Worldwide Conservation Fund: https://thewaltdisneycompany.com/environment/#disney-conservation-fund; Drywood Yarrow Conservation Partnership: Environment Canada Science Horizons: http://www.ec.gc.ca/scitech/default.asp?lang=En&n=B58899DC-1; Glacier National Park Conservancy: https://www.glacierconservancy.org/; International Association for Bear Research and Management: http://www.bearbiology.com/; Minister’s Special License: http://www.afga.org/ministers-special-licence.html; Miistakis Institute: http://www.rockies.ca/; Nature Conservancy of Canada: http://www.natureconservancy.ca/en/; Natural Sciences and Engineering Research Council of Canada: http://www.nserc-crsng.gc.ca/index_eng.asp; National Science Foundation Division of Environmental Biology: https://www.nsf.gov/funding/pgm_list.jsp?org=DEB, Grant # 0919239; Parks Canada: http://www.pc.gc.ca/eng/index.aspx; Safari Club International Foundation: http://safariclubfoundation.org/; Safari Club International Northern Alberta Chapter: http://sci-northern.ab.ca/; Shell Canada: http://www.shell.ca/; TD Friends of the Environment Foundation: https://fef.td.com/; University of Alberta: https://ualberta.ca/; US Geological Survey: http://www.usgs.gov/; US Bureau of Land Management: http://www.blm.gov/wo/st/en.html; US Forest Service: http://www.fs.fed.us/; Waterton Biosphere Reserve Association: http://www.watertonbiosphere.com/; Yellowstone to Yukon: https://y2y.net/. Additional in-kind support came from the Blackfeet Nation; Blood Tribe Land Management; Confederated Salish and Kootenai Tribes; Hab-Tec Environmental; Montana Department of Fish, Wildlife, and Parks; Montana Department of Natural Resources and Conservation; National Park Service; Northwest Connections; and the US Fish and Wildlife Service. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.