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Mortality Risk Modeling
What are they?: Movement Corridor Models predict where
grizzly bears will travel on the landscape to get from one high
use area to another. How are they created?: Grizzly bear location data, RSF
results, and graph theory are used to predict where a
movement corridor is likely to occur.
Foothills Research Institute’s GRIZZLY BEAR PROJECT
Movement Corridor
Modeling What are they?: Mortality Risk Models predict where
on the landscape grizzly bears
are most likely to die.
How can this information be used?:
Corridors important for maintaining
connections between grizzly bear high
use areas are revealed. High use
areas at risk of becoming isolated are highlighted. Efforts to
preserve these important movement corridors can be made.
Corridor Modeling led by Barb Schwab and Dr. Barry Boot
(Wilfred Laurier University)
Modeling led by Dr.
Scott Nielsen (U of
Alberta)
How are they created?:
Using our RSF models and grizzly
bear mortality locations, we are
able to predict (model) where on
the landscape grizzly bear
mortalities are likely to occur.
Most grizzly bears are killed
within 100m of a road.
DNA Population Censuses Why is this necessary?: Wildlife managers need accurate population size
estimates to determine proper management actions. Each census will provide
a population size estimate for one population unit for that year. Several years
later the census is planned to be repeated in the same unit again. With these data,
we will be able to determine whether grizzly bear numbers in that population unit
are increasing, decreasing or are stable.
How?: Hair snare sites using barbed wire to snag hair
and smelly liquid bait to attract bears into the site will
be used to obtain hair samples. DNA will be used to
identify individual bears. Population size will be
estimated based on mark/recapture statistics.
Grizzly Bear Health
How?: 1) Develop a method to determine the health of grizzly bears. Blood, skin, hair and physical
measurements taken from bears captured for collaring purposes since 1999 were analyzed and
provided more than 100 measures of health. These data were combined into several “health function
scores” that corresponded to different biological functions (e.g. growth, immunity, and reproduction)
Area Population Confidence
Sampled Estimate Interval
Yellow 42 36-55
Purple 46 41-52
Blue 90 75-116
Pink 52 38-87
Red TBA
DNA Censuses led by the Foothills Research Institute and funded by ASRD
2004
2005
2006
2007
2008
Grizzly Bear DNA Census Boundaries
Based on Grizzly Bear Population Units
Mortality Risk Map
Relatively few bears
were found in the
roaded portion of the
census areas.
Results to Date*:
Height of blue lines is
proportional to
number of GB hits at
DNA bait sites
DNA census hits, 2004-2005, looking west
Why?: When “stressed” for weeks, months, or years an animal may lose the capacity to sustain biological
functions at normal levels and gradually develop signs of impaired health (or distress) including reduced
growth, reproduction and immune function. For distressed bears, we want to determine the cause of their
stress so that appropriate actions can be taken.
Results to date: Preliminary results suggest that the suite of hormones and proteins obtained from blood, skin and hair
and the health function scores we developed is a useful way of assessing the health of grizzly bears and possibly other
species at risk. We are currently examining the health results with landscape variables (road density, forest age,
fragmentation etc.) to determine if a correlation between “stressed” bears and the landscape exists. Health Research led by Dr. Marc Cattet (Canadian Cooperative Wildlife Health Centre), Dr. David Janz (U of Saskatchewan) and Dr.
Matt Vijayan (U of Waterloo)
and together provided a health profile for individual bears. 2) Examine health results in conjunction with landscape features
of where each bear lived to determine if any relationships exits between stressed bears and the landscape. 3) Investigate
ways to remotely obtain hair and skin samples from grizzly bears without having to capture them to allow us to assess the
health of grizzly bears in a less invasive way.
*Further information at www.srd.gov.ab.ca/fishwildlife/wildlifeinalberta/grizzlybearmanagement