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EASTERN SLOPES GRIZZLY BEAR PROJECT HABITAT STUDIES
Habitat inventory, evaluation and mapping results from the Eastern
Slopes Grizzly Bear Project have been presented within three different
technical reports as of December 1998. Summarized below are the background
and results of each report. More detail about the first two reports is
available by following the links for each title.
"Grizzly Bear Population and Habitat Status in Banff National
Park" (Gibeau et al. 1996)
This report was completed at the request of the Banff Bow Valley Task
Force whose mandate it was to study the cumulative effects of human
development and activities in the Bow River valley of Banff National Park,
Alberta. At the time that this study was commissioned, habitat inventory
and mapping had not been completed by the ESGBP within Banff National
Park. The authors relied instead upon an existing food habits model for
the 4 Mountain Parks by Kansas and Riddell (1995) as a basis for habitat
effectiveness and security area analysis. This model was used to assess
inherent food potential for 40 Bear Management Units (BMUs) encompassing
9,344 km2 of land in Banff, Kootenay and Yoho National Parks.
Results showed that a significant portion of the study area was only
moderately productive habitat, much of this due to the high percentage of
rock, ice and high elevation tundra in the study area. Highest habitat
quality occurred primarily in those BMUs encompassing a high percentage of
valley bottom and Montane habitats. Habitat effectiveness modelling was
completed by overlaying human use features onto habitat mapping to
calculate "realized habitat potential" values per BMU.
Disturbance coefficients and zones of influence from the Yellowstone
Ecosystem were adopted for various types and intensities of human use.
Average habitat effectiveness for the entire study area was 83.1% ranging
from 46.6% to 97.9% per BMU. Forty-four (44%) of the BMUs in Banff
National park were below 80% habitat effectiveness.
The authors also evaluated the effect of changing levels of human use
and prescribed fire on security areas available to grizzly bears for the
time periods 1950, 1995, and 2045. A successional model of grizzly bear
habitat suitability of mapped ecosites was developed to aid in these
assessments. Results showed that the lower elevation Montane ecoregion
currently supports only 2.5% of its land area as security areas, as
opposed to 45% and 41.2% for the Lower and Upper Subalpine regions
respectively. Human land use activities occurring between 1950 and 1995
reduced grizzly bear habitat security in the Montane region greater than
double the amount of lands at higher elevations. Under a 6% growth
scenario when projected to 2045, secure habitat for grizzly bears in the
Montane region of Banff National Park would be all but eliminated. By
limiting human activities in selected areas secure habitat for grizzly
bears could be increased by 31% for the current time period. Fire
suppression over the last 60 years has significantly reduced the amount of
high quality grizzly bear habitat in Banff National Park. Introduction of
a hypothetical fire regime increased the amount of high quality grizzly
bear habitat in secure areas approximately 1.5 orders of magnitude by the
year 2045.
"Grizzly Bear Population and Habitat Status in Kananaskis Country,
Alberta" (Eastern Slopes Grizzly Bear Project 1998)
This report was prepared by 4 members of the Eastern Slopes Grizzly
Bear Project study team at the request of Alberta Environmental
Protection, Natural Resources Service as part of their Kananaskis Country
Recreation Policy Review. The analyses in this study benefited from 4
years of field research and preliminary analysis in Kananaskis Country. A
5712 km2 study area encompassing all of Kananaskis Country was
subdivided into 13 Bear Management Units ranging in size from 206 km2 to 463 km2. Five hierarchically nested habitat maps were
completed for the study area using digital overlays of vegetation and
topographic maps (Kansas and Newyar 1998). Level 4 mapping resulted in 122
different recurring map units for the study area. This level of mapping
formed the framework for grizzly bear habitat modelling. 1411 detailed
ground sample plots that collected data on key grizzly bear foods fueled
models. An average of 12.7 plots were collected per Level 4 map unit.
Habitats with highest suitability for the pre-berry season (den emergence
to July 15) included: 1) moderately to steeply sloping shrublands in the
subalpine region; 2) riparian spruce and conifer-dominated mixedwood
forests in the Lower Foothills and Lower Subalpine regions; 3) south to
west facing, moderately sloping deciduous forests; 4) treed clearcuts; 5)
gently sloping pine-mixedwood forest in the Lower Foothills and Lower
Subalpine; and 6) steeply sloping, south to west facing grasslands in the
Subalpine region. Patches of high suitability habitat in the pre-berry
season were concentrated along the major river systems including the
Kananaskis, Highwood and Bow River valleys. Highest suitability habitats
during the berry-and-after season (July 16 to den entry) were: 1) treed
and shrub sapling clearcuts; 2) moderately to steeply sloping south to
west facing shrublands; 3) moderately to steeply sloping south to west
facing Lodgepole pine forests and pine mixedwood forests in the Lower
Foothills and Lower Subalpine regions; and 4) riparian Balsam Poplar and
White spruce forests in the Lower Foothills and Lower Subalpine. High
suitability habitat during the berry and after season was limited in the
eastern portions of the Front Range BMUs.
Habitat effectiveness values were calculated for the 13 BMUs using the
same disturbance coefficients and zones of influence that were used for
the Banff Bow Valley Study (Gibeau et al. 1996). Values ranged from 49% to
82% and averaged 71%. Lowest habitat effectiveness values were found in
BMUs that encompassed major river valleys in the western portion of
Kananaskis Country. This was thought to be due to the concentration of
human activities along highly suitable river valley habitats.
"Eastern Slopes Grizzly Bear Project: Habitat Mapping and
Evaluation Component"(Kansas and Newyar 1998)
This progress report summarizes 4 seasons of habitat inventory and
mapping and grizzly bear habitat use for the period 1994 to 1997. The
habitat inventory and mapping data are focussed on a 5712 km2 study area on Alberta provincial lands surrounding Kananaskis Country. The
habitat use analyses combined data from both Kananaskis Country and Banff
National Park.
A total of 1400 detailed habitat availability plots were completed in
the Kananaskis study area. These plots collected information on bear foods
and security cover and form the basis for completing both grizzly bear and
ungulate habitat models. Grizzly bear habitat use information was recorded
at 951 feeding sites. These sample plots collected enough plant cover
information to classify the plant association or micro-habitat inclusion
type, and recorded type of use, intensity of use, approximate age of sign,
and the particular plant or animal foods utilized. Along with
radio-telemetry data these plots will be used to verify the accuracy of
completed and evolving habitat suitability models.
Five hierarchically-nested habitat maps were completed for the study
area. Each map was built from the next most detailed map through a
progressive grouping and classification process. Digital overlays of
1:20,000 scale forest cover mapping and 1:20,000 scale digital elevation
model derivatives (slope, aspect, elevation) formed the basis for this
mapping. The purpose of this approach was to provide a wide range of map
products and mapping scales for planning, evaluation and statistical
analysis. This approach also will form the basis for John Kansas’ M.Sc.
Thesis which will test the effects of habitat inventory and mapping scale
on habitat evaluation output as this influences habitat effectiveness
models. The report also summarizes the results of a Landsat-TM based
classification and mapping of land cover for the study area.
Preliminary summaries of grizzly bear habitat use were done of 951
feeding sites throughout Kananaskis Country and Banff National Park. These
summaries included relationships between feeding sites and aspect (5
classes), elevation (4 classes), ecological region (4 classes), vegetation
cover type (24 classes), and food type (7 types). Also summarized were the
extent to which and habitats within bears utilized non-mappable
micro-habitat inclusions. Results of these summaries are preliminary and
require further analysis at this point in time.
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