Balmy Start to Minnesota's Winter - Impact on Wildlife

The following is from an article retrieved from the Star Tribune Web Site.

To be published Sunday, December 6, 1998

Schara: Wildlife reap a winter windfall
Ron Schara / Star Tribune

A mild December is nature's version of a windfall. Almost everything 
wins in the game of survival -- except for snowshoe hare.

"Yah, they're running around the woods up here as white as can be, 
sticking out like a sore thumb," DNR wildlife biologist Bill Berg of 
Grand Rapids said last week.

Wearing a white fur coat, while hopping around a brown forest floor, 
isn't exactly good for your health if, for example, you're a snowshoe 
hare in a woods full of owls or if you're a weasel who's trying to be 
stealthy.

Those are exceptions, however. Minnesota's December weather already has 
paid fish and wildlife dividends that may extend well into next year's 
crop of critters.

Including fish.

"For sure, the threat of a fish winter kill will be much, much less 
because of the mild weather," DNR fish biologist Jeff Gorton said. 
"Winter kills are based on oxygen supply and demand, but it takes snow 
and thick ice to slow down photosynthesis and reduce oxygen in a lake."

In severe winters, Minnesota might have dozens of lakes suffer fish 
kills.

"If we have a normal ending to winter, say in March, a winter kill 
probably won't happen," Gorton said.

(A possible fishy downside to balmy December air resides in DNR walleye 
rearing ponds, which depend on winter kill to "clean" the ponds after 
the walleyes have been netted and stocked. Gorton said if some walleyes 
escape the nets and survive in the ponds, they will feed heavily on the 
"baby" walleyes released in the ponds next spring.)

What about ruffed grouse who have no snow to roost under at night?

"I think the grouse are probably doing fine," Berg said. "Cold 
temperatures with no snow is the worst. The only time we've seen frozen 
grouse in a snowless winter was with super low wind chills and, so far, 
we haven't had those."

Ringneck pheasants, sharp-tail grouse and Hungarian partridge -- all 
ground feeding and ground roosting bird species -- benefit from mild 
temperatures and snowless terrain. In one severe blizzard, populations 
of these birds might be reduced by 50 percent or more.

What about waterfowl who don't have to fly south?

"That may not be a blessing," Berg said. "Mild weather in late fall 
tends to retard the migration and tends to concentrate ducks and geese, 
which makes them vulnerable to diseases, such as avian cholera."

While a short migration might seem safer, Berg said migrating species 
are designed to disperse southward and probably are healthier because of 
it.

More critters:

Deer? You kidding? Berg said that deer are having a party. Food is 
easily reached and natural enemies, such as coyotes and wolves, don't 
have the advantage that snow provides.

Bear? Nothing bothers a sleeping bear much. Said Berg, "They pretty much 
stay in their dens no matter the winter weather. And they don't come out 
any earlier either."

Carrol Henderson, DNR non-game supervisor, said what's good for hawks 
and owls this winter has been bad for field mice. "The hawks and owls 
have had pretty easy pickings with the lack of snow," Henderson said.

Ditto for songbirds.

Minnesota's timberwolves might not be howling with joy. Said Berg, 
"These are poor deer hunting conditions for wolves so it's tougher to 
make a living. I suspect small mammals are playing a larger part in a 
wolf's diet right now."

Other predators, such as skunks and raccoons, are active in mild winter 
periods but return to sleeping during cold snaps.

"Normally at this time, they are living on stored fat," Berg said.

Red fox may have easier hunting but mange is a disease that tends to 
increase under mild winter conditions.

In a nutshell, this unusual December means the threat of winter-caused 
wildlife losses is almost a non-issue.

"At this point, it would really take a rough winter in January and 
February to harm deer populations," Berg said.

It's not all good news, however.

Folks in Grand Rapids, Minn., recently reported seeing December 
mosquitoes flying around and looking for blood. If so, it can only mean 
biting black flies could be here for Christmas.

Keep your longjohns handy.

 Copyright 1998 Star Tribune. All rights reserved. 

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