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Ask UMD graduate student Nick McCann about his current NRRI research
project and you'll get a big grin. He spends an inordinate amount
of time focused on animal excrement—specifically, snowshoe hare
pellets.
He's quick to explain why counting hare pellets in the Superior
National Forest is important. Snowshoe hares are the primary food
source of the Canada lynx. The pellet counts offer another way for
forest managers to locate lynx, listed as a federally threatened
species in 2000.
“The theory is really quite simple,” McCann explained. “If pellet
counts indicate how many hares are in the forest, then perhaps hare
distribution can tell us where the lynx are spending their time.”
First, McCann had to scientifically determine if pellet counts
truly indicate how many hares are using an area of the forest. Using
six study grids in the Superior National Forest (13.5 hectares—approximately
5.4 acres—each) he counted pellets and trapped hares in 36 box-traps.
Preliminary results are showing that pellets indicate hare presence.
The second step was to determine what types of forests hare prefer
by correlating pellet counts with forest cover. This is made easier
using geographical information system (GIS) analysis to identify
forest cover-types that yield disproportionately high or low pellet
counts at transects dispersed throughout the forest.
“Our data shows that hares are spending a disproportionately high
amount of time in areas of upland shrub and less time in aspen/white
birch areas of the forest,” McCann explained.
The last question, then, is whether these are also the forest cover-types
known to be preferred by the Canada lynx? Yes. Data from GPS-collared
lynx in the Superior National Forest correlates well with data from
the pellet-count study. Where there are snowshoe hares, there are
likely to be Canada lynx.
“For forest managers, this means they can narrow down their search
for lynx by doing a hare pellet count. At least, it will tell them
where the lynx are not,” said McCann.
Written by June Kallestad
Reprinted with permission from the spring/summer 2006 edition of
NRRI
Now, a publication of the Natural Resources Research Institute.
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