VIRGINIA
TECH BEAR RESEARCHERS
ENSURE POPULATIONS
BLACKSBURG,
Feb 28, 2003 The Cooperative
Alleghany Bear Study
(CABS) was initiated
in 1994 as a 10-year
study to ensure survival
of Virginia’s hunted
black bear population
of western Virginia.
During the first six
years of the study,
researchers have placed
radio collars on 376
of the 746 bears captured.
Michael Vaughan, Virginia
Tech’s internationally
known wildlife sciences
professor in the College
of Natural Resources,
works with graduate
students Andrew Bridges,
Daniel Lee, Colleen
Olfenbuttel, and Sybille
Klenzendorf to study
the bear population
in the Alleghany Mountains.
Sybille Klenzendorf,
fisheries and wildlife
Ph.D. graduate, focused
part of her research
on the effect of radio-collars
on black bear survival
in Giles, Craig, and
Montgomery counties.
“No study to our knowledge,"
says Vaughan, "has
evaluated the impact
of radio-collars on
hunter selectivity
for bears and the
influence on bear
survival.” Klenzendorf
suspected that collared
bears had a higher
survival rate than
non-collared bears
due to hunter bias.
Her research found
a significant difference
in the survival rate
of radio-collared
versus non-radio-collared
females. “Bear hunters
in Virginia tend not
to kill female bears
if they can identify
the sex,” explains
Vaughan. “We suspect
that hunters successfully
avoided harvesting
radio-collared bears,”
continues Klenzendorf.
“In hunted populations
in which hunters have
a goal of saving females
to increase population
size, those conducting
radio-telemetry studies
should be aware of
possible bias for
their survival estimates.”
Daniel Lee, graduate
student in fisheries
and wildlife, focused
his research on dispersal
distance movements
of sub-adult black
bears in Augusta and
Rockingham counties.
He found that juvenile
bears migrate over
a span of less than
one to 52 miles. During
his three-year study,
Lee used ear tag transmitters
to avoid potential
in-grown collars.
His findings show
that the female population
moves very slowly.
The males, however,
had a much greater
dispersal rate. Research
shows that the males
tended to move along
the ridge lines going
northeast or southwest.
Lee concluded that
the further the males
moved or the greater
the dispersal distance
traveled, the less
they were harvested
by hunters. Overall
the dispersal distance
movements were helping
the bears’ survival
rate. Andrew Bridges,
Ph.D. candidate in
fisheries and wildlife
sciences, developed
a morphometric-based
dichotomous key that
could be used in the
field to correctly
age one, two, and
three-year old bears.
Prior to the development
of the key, one-year
olds were frequently
misidentified as two
or three-year olds
and vice versa. Vaughan
and his graduate students
traveled to Steinkjer,
Norway, to present
their findings at
the 14th International
Conference on Bear
Research and Management.
Colleen Olfenbuttel,
graduate student in
fisheries and wildlife
sciences, won Best
Presentation Award
at the conference
for her paper on the
use of ultrasonography
as a non-invasive
tool to detect and
monitor black bear
fetal development.
Lead researcher, Michael
Vaughan is assistant
leader of the Virginia
Cooperative of Fish
and Wildlife Research,
USGS-BRD. He has served
as vice president
to the International
Association for Bear
Research and Management
(IBA), and editor
of the IBA's journal,
URSUS (scientific
name for bears).
