Scientists say wolves will help most species
By Paula Clawson, Enterprise Staff Writer
No one
can really predict how wolves will affect the Yellowstone
ecosystem in the long term, but a recent article in a scientific
journal predicts more good than bad.
“We
think there’s going to be a better balance in term
of species composition,” said Doug Smith, Yellowstone
National Park wolf project leader.
Smith,
who has managed wolf reintroduction in the park since it
began in 1995, co-wrote an April 2003 BioScience magazine
article.
The
article broadly predicts that almost all plant and animal
species — except coyotes — will benefit from
wolves in Yellowstone.
“I
wanted to write this article to respond to the maelstrom
and controversy over wolves,” Smith said in an interview
Thursday. “It seems like everyone in the world is weighing in on what wolves will do, so we decided to weigh
in, too.”
BioScience,
like most scientific magazines, puts articles through a
peer review to assure the conclusions accurately reflect
the science, Smith said.
Smith’s
co-authors are Rolf Peterson and Doug Houston. Peterson
has studied wolves on Isle Royale National Park in Lake
Superior since 1970 and Houston, a research biologist, worked
in Yellowstone from 1970 to 1979.
“Rolf
is one of the world’s leading authorities on wolves,”
Smith said.
Wolves
moved onto Isle Royale in the late 1940s and prey on moose.
Smith acknowledged it was hard to compare Isle Royale and
Yellowstone, but there were some similarities.
For
instance, it took the Isle Royale wolves eight years to
wipe out the coyote population. On the northern range of
Yellowstone, the coyote population has decreased about 50
percent since the wolves returned.
The
article examines most of the major animal and vegetation
species in Yellowstone. It points out that bears and cougars
are not hurt by wolves and may actually be helped.
“Last
year the grizzlies’ primary fall food source, white
bark pine nuts, was a failed crop. They bears turned to
wolf kills to feed, which definitely helped them,”
Smith said.
Wolves
rarely can bring down bears in a fight for food. The article
cites an instance where a bear on a wolf-killed carcass
held off 24 wolves.
The
Yellowstone wolves primary food is elk. Elk populations
have fallen since wolf reintroduction. In the early 1990s
the Yellowstone Northern Range elk population reached around
19,000 and by 2002 it had dropped to about 9,500.
But
according to the article, while wolves are an important
factor in elk decline, so are variables such as harsh winters
and/or drought, and human hunters outside the park boundaries.
“Some
curtailment of midwinter shooting of cow elk outside the
park might be necessary, because wolves and humans … compete
over common prey,” the article stated. “Successful
coexistence of wolves and human hunters is a management conundrum that will test wildlife managers and challenge
long-held beliefs.”
Smith
said the political argument of whether wolf management should
reflect local or national desires can’t be addressed
by science.
“A
big point of the article is it’s not just about elk,”
Smith said. “Wolves have a lot of interaction at all
levels of the ecosystem, and hey, it’s the whole ecosystem Americans are concerned about.
“Americans
don’t want Yellowstone to just be an elk farm.”
———
“Yellowstone
After Wolves” in the April 2003 issue of BioScience
can be ordered for free online at www.aibs.org/biosciencelibrary.
Select “Buy Single Articles” and choose the
article.