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By David Weymiller Daily University Science
News
The groundhog,
celebrated with a special day Friday, Feb. 2, in the United States,
is one of six marmot species in North America, but unless a team
of managers and scientists are successful, the number of species
found on this continent could shrink to five.
The research
team includes a Colorado State University biologist, Greg Florant,
professor of biology and an expert on marmot physiology. Florant
is a member of the Scientific Advisory Group to the Vancouver
Island Marmot Recovery Team that met in mid-January to discuss
the issue.
The Vancouver
Island marmot, whose range is entirely in Canada, is on the U.S.
endangered species list as well as Canada's.
Scientists
count 36 Vancouver Island marmots surviving in the wild, with
39 in captivity. To help draw attention to Canada's most-endangered
species, British Columbia in 1998 declared May 1 as "Vancouver
Island Marmot Day." The date, Florant said, reminds people
that a "Mayday" call has been issued for the species.
(The groundhog, also known as a "woodchuck" or "whistling
pig," is more common and not threatened.)
For the Vancouver
Island species, "the 'problem' is a host of different things,"
said Florant, who spent last spring in Austria on a Senior Fulbright
Research Fellowship investigating the physiology and hibernation
patterns of the Alpine marmot.
The precipitous
drop in the Vancouver Island marmot's numbers since about 1980
could be due to disease; nutrition; possible global warming; increased
predation from wolves, cougars and golden eagles; and human activities
such as clear-cutting forests.
"Clear-cutting
initially makes good marmot habitat," said Florant. "However,
as vegetation returns, the habitat changes. Hiding places for
predators, difficulty in finding suitable places for marmot hibernation,
even changes in marmot food plants can reduce the value of the
clear cuts and leave the marmot population occupying them with
nowhere to go."
With an average
life expectancy of eight to 10 years, two-year-old males and even
some females are kicked out of the large group in which they were
raised to find their own territory. It's possible, Florant said,
that they're drawn to clear cuts, but after a few years the once-inviting
areas prove less than ideal in sustaining the little rodents.
Florant is
worried about nutritional issues. His previous research shows
that leafy plants, seeds and nuts eaten during the warm season
contain two fatty acids, linoleic (18:2n-6) and linolenic acid
(18:3n-3). They are key molecules for successful marmot hibernation,
during which body temperatures drop and metabolism slows.
However, his
research shows that larger amounts of linolenic acid can make
the animal active and cause it to feed when it's supposed to be
hibernating. Florant hypothesizes that linolenic acid levels in
American groundhogs, and not their shadows, determine whether
they emerge from hibernation early.
Excess linolenic
acid could also disrupt the hibernation of Vancouver Island marmots.
Significantly, some research suggests that most of them die during
winter.
A marmot "halfway
house" stands atop Vancouver Island's Mount Washington so
that captive marmots can get outside, see predators and prepare
for life in the wild.
"Basically,
what we're talking about is getting them breeding in captivity
as fast as we can," Florant said. "We've got captive
breeding now, and I think we can bring the Vancouver Island marmot
back. But we have the whole matter of habitat for marmots and
other animals, and that's the larger issue."
Florant received
his doctorate from Stanford University in 1978 and bachelor's
degree from Cornell University in 1973. He taught at Swarthmore
College and Temple University before joining Colorado State in
1995.
Groundhog
Day shares Feb. 2 with an ancient European Christian festival
called "Candlemas," which presaged the coming of spring.
Farmers decided if a hedgehog emerged from its burrow and saw
its shadow there'd be six more weeks of winter. German farmers
brought the tradition to the United States. Lacking hedgehogs,
they adopted the groundhog.
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