Caribou habitat in
Alberta ravaged
beyond repair
Disturbance in Alberta's northwestern
foothills will make restoration selective
The Canadian Press
http://www.cbc.ca/1.2745870
Scientists studying the ravaged caribou habitat of Alberta's
northwestern foothills say they have found so much disturbance
from decades of industrial use that restoration of the terrain will
have to be selective.
"There's just so much disturbance, it's important we prioritize,"
said Laura Finnegan, a biologist with the Foothills Research
Institute in Hinton, Alta.
- The institute is one year into a three-year study on how
- animals and humans continue to use this ragged
- landscape in an effort to understand how to best restore it.
Governments are counting on that work to help them live up
to promises of sustainable development.
Deforestation worse than in
Brazil
This stretch of foothills still looks like pristine, trackless boreal
forest when seen from the highway. But back roads into the
bush reveal a patchwork of clearcuts, well pads, access
roads and seismic lines so extensive that gravel and green
greet the eye almost equally.
There are more than 16,000 kilometres of seismic lines, cut
by the energy industry through the forest, within the study
area's 13,000 square kilometres.It's part of an area that
recent satellite data suggests is being deforested at a rate
that outpaces what's going on in Brazil's rainforests.
About five per cent of range for the Little Smoky and a la
Peche caribou herds remains undisturbed — a long way
from the federal government's 65 per cent target.
Finnegan and her colleagues are trying to figure out
how to bridge that gap. Their first step is to understand
how both animals and humans are using what's on the
ground.
That means understanding the impact of seismic lines,
which are used to study geology underground.
Wolves normally prefer to prey on deer and moose, but
seismic lines allow them to penetrate into the deep
woods where caribou hide .Caribou also normally
avoid coming within 500 metres
avoid coming within 500 metres
of a seismic line, making every line, in effect, a kilometre
wide.It takes up to 70 years in this cold climate for nature to
efface a seismic line. The passage of even a single quad
can retard that restorative creep by crushing plants and
compacting soil.
"You can just look at the vegetation on the line and you'll
see tracks," Finnegan said.
Snowmobiles ravaging the terrain
Researchers have used sophisticated satellite-based radar
to map average vegetation heights across the entire study
area to within a few centimetres.
They've erected motion-sensitive cameras on selected seismic
lines to record what's using them — caribou, wolves and
snowmobilers alike.
Preliminary results suggest there's a threshold at which
the lines are no longer an easy way for animals to get around.
"Seismic lines with vegetation heights less than 1.4 metres
facilitate movement by caribou predators," says the institute's
report.
Human use is more complex. Snowmobilers and quadders
prefer little ground cover and dry soils as well as lower
vegetation.
"Human motorized use of seismic lines is extensive across
the range of a la Peche and Little Smoky caribou, and the
probability of high levels of motorized human use increased
when vegetation height along seismic lines was less than
two metres in height," says the report.
Mapping where seismic lines attractive to predators and
humans cross what used to be the best caribou habitat
could suggest where restoration could do the most good
, the researchers say.
Such maps have been produced for the institute's
preliminary report. Priority seismic lines for restoration
preliminary report. Priority seismic lines for restoration
will still add up to many hundreds of kilometres — and
the study area is only one small part of a heavily affected
natural region that stretches almost all the way down
Alberta's western edge.
But the institute's work could provide at least a plan to
get started, Finnegan said.
"That's the primary goal of this research, so that land
managers on the ground could look at it and know
where to begin."
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