Advertising Dominance or Sexual Availability: The Use of Rub Trees by Brown Bears

Nevin, Owen (2007) Advertising Dominance or Sexual Availability: The Use of Rub Trees by Brown Bears. In: 18th International Conference on Bear Research & Management, 4 -11 November 2007, Monterrey, Nuevo León, México. Full text not available from this repository.

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Currently we lack an understanding of olfactory communication in bears. This applies to both opportunistic
marking during social interaction and the use of rub trees (trees that are bitten and rubbed by many
bears each year) to transfer social information. Both of these forms of communication should be the
focus of field and captive studies. I conducted a base line ethological study of olfactory communication
in brown bears (Ursus arctos). While bears are often considered solitary, aggregations favouring social
learning and complex social interaction are much in evidence. High density populations associated
with coastal salmon runs provide an opportunity to study their behavioural response in close proximity
to other adult bears, which would be difficult, if not impossible, in low density mountain populations.
I will present data on the relationships between use of rub trees and sex/dominance/reproductive
availability. Data was recorded over 167 camera-trap-nights in the Glendale valley, British Columbia
in May and June 2005 and 2006. To reliably document social interactions and communication in free
living wildlife it is essential that individuals can be identified. Photo-identification techniques allow
individual bears to be distinguished. Coat coloration and scar patterns were recorded with sketches
and descriptions on data sheets, supplemented by a catalogue of reference photographs. Each bear
was given a unique numeric code. Sex is determined by urination pattern, direct observation of genitals
or the presence of cubs. Since research began at the Glendale field site in 1999 an ongoing record of
photo identified bears has been maintained and updated annually and now contains of more than 30
recognisable adult brown bears. I will highlight the potential impact of ecotourism/bear viewing activities
on marking, courtship and breeding behaviour: During its initial growth the bear viewing/ecotourism
industry in Alaska and British Columbia has focused the majority of activity on autumn salmon feeding
aggregations introducing high levels of human activity to some of these sites. With increased demand
and repeat visitation bear viewing activities during the spring breeding season are increasing. With
studies reporting that large male bears avoid people both temporally and spatially it is critical that we
broaden our understanding of olfactory communication, its role in courtship and breeding, and the
potential impacts of the rapidly expanding ecotourism industry on normal breeding behaviour. Are large
adult males being displaced by spring viewing? Does this reduce their marking or otherwise impact
their breeding opportunities? How does this impact the management of bear populations, especially
in light of the sexually-selected infanticide? I will draw on data from ongoing telemetry studies in the
region to inform this debate.

Item Type: Conference or Workshop Item (Speech)
Journal or Publication Title: n/a
Departments: Faculty of Health and Science > Science, Natural Resources and Outdoor Studies > Forestry, Conservation & Applied Science
Depositing User: Insight Administrator
Date Deposited: 30 Mar 2011 16:21
Last Modified: 26 Aug 2016 16:09

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