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BIGHORN
SHEEP RECOVERING
San Gabriel Mountains
bighorn population on an
upward trend
By JIM MATTHEWS
Outdoor News Service
The population of
bighorn sheep in the San
Gabriel Mountains is
growing, according to
results from a
comprehensive field
survey completed two
weeks ago by the
Department of Fish and
Game, the U.S. Forest
Service, and over 100
volunteers who took part
in the counting effort.
The ratio of lambs to
ewes was the highest
ever recorded since
surveys began in 1976,
an indicator of a
healthy and growing
herd. The bighorns were
counted from the air, by
DFG and USFS staff in a
helicopter, and from the
ground by volunteers in
all of the major sheep
habitat in the mountain
range. A total of 142
sheep were counted from
the air and another 55
from the ground, said
DFG biologist Jeff
Villepique. Since the
ground and air surveys
were conducted
simultaneously,
Villepique said they
were able to estimate
the total population
with a high degree of
accuracy at 308 animals.
This is up slightly from
last year's 292
estimate. Once the
largest herd of bighorn
in the state, numbering
over 700 animals in the
late 1970s and early
1980s, the population
crashed to around 100
animals or less from
1995 through 2002. It
has been growing
steadily since. "The
biggest factor in the
current growth, I think,
is the fires in 2003,"
said Villepique. "There
were two good fires that
got a lot of that front
country where the sheep
live. I think that's the
big factor -- a lot of
that habitat was
overgrown."
The lamb-to-ewe ratio
was 62 young per 100
ewes, and the highest
ratio recorded before
this was just over 50
lambs in 2004. Most
years the ratio is
between 25 and 35 lambs
for each 100 ewes.
Villepique called the
number of young "really
encouraging," especially
considering that just
five years ago,
biologists were
concerned the wild sheep
population could
completely disappear
from the San Gabriels.
These surveys have been
done almost continuously
since 1976, but the
volunteer ground
component has returned
again just the last two
counts. The ground
counting, done in
conjunction with the
aerial survey, gives
wildlife biologists much
more accurate population
estimates and higher
total counts with which
to make those estimates.
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