Lab Blogs

From field to lab – preparing 2018 bear hair for stable isotope analysis

Microwell with capsules of bear hair

Above image: The prepared samples (tin capsules filled with ~3mm of hair) ready to be sent for analysis. Each sample represents hair from an individual bear.

It’s that time of year again. The bear hair samples collected during the 2018 grizzly and black bear monitoring season with our Coast First Nation partners have safely made their way back to us for analysis. After the field season wraps up each year, the samples collected are first sent for genetic analysis at Wildlife Genetics International. They are then returned to us along with the new genetic information (species, sex, and individual identity), allowing us to answer key questions such as: ‘Which bears were detected this year?’, ‘Were there any new/previously undetected individuals this year?’, ‘Did individuals travel among sites?’, and, ‘Is this new individual a male or female?’. These simple questions inform our ‘downstream’ analyses on the relationship between, for example, salmon abundance and population dynamic or movement.

A sample of bear hair left behind at a barbed-wire corral during the 2018 season
A sample of bear hair left behind at a barbed-wire corral during the 2018 season.

It is now up to a dedicated team of volunteers to prepare the samples for stable isotope analysis. Sample preparation is time-consuming and repetitive; a good podcast or playlist to tune-out to is essential. However, this invaluable step allows us to answer the big questions regarding these individual bears’ diets, such as whether higher salmon diversity in areas predicts higher salmon consumption by bears, or whether there are spatial patterns in salmon consumption between bear sexes and species.

During the preparation, each sample gets washed in a chloroform/methanol mixture to remove debris, then carefully cut into very tiny (~3mm!) pieces, and then individually weighed. Afterwards, they are wrapped up into tin capsules and shipped to the University of Saskatchewan for analysis. These preparatory steps are taken for hundreds of samples each year; it soon becomes clear the time and energy required by volunteer technicians in preparing them.

Rowen Monks prepares a hair sample for stable isotope analysis.
Volunteer Rowen Monks prepares a hair sample for stable isotope analysis.

We are immensely grateful to our volunteers each year, without whom this work wouldn’t be possible!

By Ilona Mihalik, Research Associate