Photos and text by Eric Fowler
Published October 2010
Like many other wildlife species, elk are difficult to count.
They are highly mobile -- here one day and gone the next --
and typically stick to heavy cover during daylight hours. Commission
biologists have been trying to get a more accurate count of
elk in the Pine Ridge through helicopter surveys during the
past three winters and by use of a population model developed
The model takes into account snow cover, tree canopy cover
and whether the elk were moving or not, all factors that can
influence how visible elk are, to estimates how many elk aren’t
seen by the flight crew.
What they found was the model won’t work in the Pine Ridge.
Only 366 elk were observed from the air, and the model estimated
the total population at 712, a number biologists are certain
is well below the true population. Often, biologists spotted
no elk in areas they know to be strongholds.
Bruce Trindle, big game research and wildlife disease specialist
in the Commission’s Norfolk office, said the model works in
Idaho because elk are counted after they move from the high
country into winter range with less tree cover. “Well guess
what?” Trindle said. “Our elk don’t come out of the mountains
and they don’t come out of the trees - that’s where they live
and they evidently don’t like to be counted. What we think
is happening is we’ve essentially got a canopy that’s too thick
and we are just not observing the elk.”
Biologists in South Dakota using the same model in the Black
Hills, where cover is similar to the Pine Ridge, also doubt
its accuracy. They improved their luck by putting radio collars
on elk and using the helicopter to locate and flush those individuals
and others with them from cover where biologists might have
spotted none. Nebraska biologists may use that tactic if and
when future surveys are flown in the Pine Ridge.
“Helicopters don’t come cheap,” Trindle said. “When you spend
several thousand dollars to get up there and fly around and
count elk and when you’re done nobody believes it, it’s probably
not money well spent.”