Biologists Find Deer Devouring Rare Flowers

  • Largeflower bellwort (Uvularia grandiflora) is one of the wildflowers declining at many of the sites studied by University of Wisconsin researchers. (Photo courtesy of Dave Rogers, UW Herbarium)

Most of us think of the white-tailed deer as a graceful and cherished part of the natural scene. But it turns out when there are too many deer, it’s bad for some of the plants in the forest. New research suggests deer may be a prime culprit in a worrisome loss of rare plants in the woods. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

Most of us think of the white-tailed deer as a graceful and cherished
part of the natural scene. But it turns out when there are too many
deer, it’s bad for some of the plants in the forest. New research
suggests deer may be a prime culprit in a worrisome loss of rare
plants in the woods. The Great Lakes Radio Consortium’s Stephanie
Hemphill reports:


Gardeners in many suburbs and rural areas know deer are good at
mowing down hosta, tulips and other favorite plants. In the woods,
deer munch on the small plants that live on the forest floor… plants
such as orchids, lilies, and other wildflowers.


Fifty years ago, researchers at the University of Wisconsin surveyed
hundreds of acres in the state, and made careful records of the plants
on those sites. In those days, the deer population was a lot lower
than it is now. In the last couple of years, two biologists went back to
many of those same sites and counted the plants living there now.


Tom Rooney says at most sites they found fewer different kinds of
plants.


“It tends to be the same species occurring over and again on the site.
You’re losing the rare species and picking up more and more
common species.”


He says they tried to link the decline in rare species to the fact that
the forest is getting older. But they found no evidence for that.
Instead, lead researcher Don Waller says the evidence points to
deer, which have increased dramatically over the last fifty years.


“The worst changes we’ve seen, ironically were in a couple of state
parks and a protected natural area, that showed losses of half or
more of species in 50 years. However, in these sites there was no
deer hunting, implying high densities of deer may be causing a lot of
the effects we see in the woods.”


Plants that rely on insects for pollination declined more than other
types of plants. Waller thinks it might be because the insect-
pollinated plants have showy flowers, which could catch the eye of a
wandering deer. As the flowering plants decline, the insects and
birds that rely on them for food could decline as well – bees, moths,
butterflies, and hummingbirds.


Waller says it’s worrisome because scientists don’t know how
particular insects and plants work together to support each other.


“As we’re losing parts of the ecosystem, we’re really not sure what
their full function is, they might play some crucial role we’re not aware
of and only too late might we become aware of the fact that this loss
led to an unraveling or threats to other species.”


Waller says the only places they studied that still have a healthy
diversity of plants are on Indian reservations. The Menominee Tribal
Forest in northeastern Wisconsin is pretty much like it used to be fifty
years ago.


(forest sounds under)


In this forest, there are only about ten deer per square mile. That’s
about as low as the deer population gets in Wisconsin. It’s not that
the tribe is hunting more deer; it’s the way the forest is grown.


Deer find lots to eat in young aspen woods; there’s less for them to
eat where pines and oaks and maples grow. Don Reiter is the wildlife
manager here. He says in the 360 square miles of the Menominee
forest, there’s really four different types of woods.


“We have pulpwood, we have northern hardwoods, white pine, red
pine, and again, the forest ecosystem as a whole, there’s plenty of
food out there for the deer.”


And because there aren’t too many deer, young pines and hemlocks
– and orchids and lilies – have a chance to grow.


In the upper Great Lakes states, wildlife officials have been trying to
thin the deer herd for several years. That’s because state officials
have been aware deer were causing problems by eating too many
plants. The recent study provides dramatic evidence.


In Minnesota, for instance, hunters are shooting four times the
number of deer they shot fifty years ago.


Steve Merchant is forest wildlife program consultant for the
Minnesota DNR. Merchant says the agency has liberalized its rules,
to encourage hunters to kill even more deer. But the number of
hunters hasn’t gone up in recent years. And lots of private
landowners post no-hunting signs.


“We need to have some help from people, people still need to get out
and hunt deer, and landowners need to provide that access for
people to harvest deer.”


Merchant says Minnesota is gradually trying to restore pine forests,
which were cut down for lumber and replaced with fast-growing
aspen. More pine forests could cut down on the deer population…


“But as long as we still have the strong demand for the aspen
markets that we do, and we manage those aspen forests in a
productive manner for wood fiber, we’re going to create a lot of good
white-tailed deer habitat.”


Merchant says it would take decades to change the woods enough to
reduce the deer population. And in the meantime, we’re losing more
and more of the rare flowers.


For the Great Lakes Radio Consortium, I’m Stephanie Hemphill.

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Reviving an Ancient Fish

Sturgeon are one of the oldest vertebrates on earth. The giant fish have survived for more than 150 million years. But encroachment by humans, and in some cases poaching, have decimated the fish in many areas, including the Great Lakes. Now the sturgeon is on the brink of extinction. That’s why hundreds of scientists from around the world came to Oshkosh, Wisconsin recently. As the Great Lakes Radio Consortium’s Patty Murray reports, they came to witness a sturgeon success story:

Transcript

Sturgeon are one of the oldest vertebrates on earth. The giant fish have survived for more than one hundred fifty million years. But encroachments by humans, and in some cases, poaching, have decimated the fish in many areas including the Great Lakes. Now the sturgeon is near the brink of extinction. That’s why hundreds of scientists from around the world came to Oshkosh, Wisconsin recently. As the Great Lakes Radio Consortium’s Patty Murray reports, they came to witness a sturgeon success story.


The sturgeon is a really big fish. It can grow six feet long and weigh as much as two hundred pounds. Because of its size it faces few challenges from any other animal, except says Ron Bruch, from humans. Bruch is a fishery biologist with the Wisconsin Department of Natural Resources. He says most of the twenty-five species of sturgeon found around the world are in trouble, including those living in the lakes here. Years ago, he says the Great Lakes used to be full of sturgeon, but European settlers didn’t like them because they tore up fishing nets.


“Nets were very expensive back then they didn’t have the fancy nylon twine and all the other equipment we have today. So these big fish would get into the nets and rip them up so they didn’t like sturgeon. So they’d just kill the sturgeon, stack them up just to get rid of them. Then they found out the fish had caviar and there was a market for caviar.”


And that meant the sturgeon began facing another threat. Today, a pint of caviar can bring as much as six hundred dollars. That’s enough money to bring out poachers.


(Sound of boat on river)


So with the sturgeon population in rapid decline, scientists are eager to find ways to save those fish that remain. That’s why many of them came to Wisconsin this summer. While most of the sturgeon population in the Great Lakes has long since disappeared, some of the fish still survive here. So scientists gathered on the banks of the Wolf River to watch as DNR wardens plucked a few of the big fish out of the water.


(Natural sounds)


Wisconsin’s Lake sturgeon population is considered to be the healthiest on earth. Sturgeon experts’ say that is because of a strong, two-pronged effort by state officials. First, they have a monitoring program. Many of the sturgeon are fitted with radio monitoring chips to keep track of how each fish is growing and where it is living.


(Sound of measuring, checking for chips)


Then, to make sure the fish remain safe, game wardens regularly patrol for poachers, and volunteers guard riverbanks during spawning season. That’s when the fish are the most vulnerable because they float close to the surface and can be easily speared. But despite these efforts, the state’s sturgeon population still holds a threatened status. Most of the fish live in the Wisconsin’s inland lakes and rivers, while very few remain in Lake Michigan, and it’s that fact which prompted a very unusual donation. An Italian count recently visited Wisconsin and learned of the fish’s decline, so he has donated two thousand dollars to study how to strengthen the population. The count’s money will pay researchers to go into Lake Michigan and Green Bay to see how many fish are left. They’ll also look at what obstacles may block restocking efforts.


Scientists hope what they learn in Lake Michigan can be applied to the rest of the Great Lakes. The money may also help fish elsewhere in the world. The count sent a team of Italian scientists to spend a week shadowing Wisconsin researchers. Darren McKenzie is an English scientist working with the Italians on preserving sturgeon in the Po River.


“Well I hope we can learn a few things about the techniques they use particularly with radio tracking and population issues. Because probably the Wisconsin lake sturgeon rehabilitation management thing, whatever it is called, is one of the best in the world for monitoring sturgeon population.”


For many of the foreign scientists, the importance of the sturgeon was brought home by a visit to a Northern Wisconsin Indian Reservation.


“Welcome to the Menominee tribal reservation. The way we look at it you’re people of the sturgeon just like we are-concerned about the sturgeon.”


For the Menominee, the sturgeon is more than just unusual looking and good tasting. The tribe’s relationship with the sturgeon goes back ten thousand years to the Menominee creation story. Before European settlers came along, the tribe relied on the fish for food and fuel. Then, in the 1890’s a dam went up downstream that stopped the sturgeon from swimming to a traditional spawning ground on Menominee land. Back then, tribal historian David Grignon says, the federal government would not let the Indians go off the reservation to spear sturgeon.


“It was denying us of a resource that we’d had for centuries. You know it was probably like the buffalo to the plains…. a way of life was gone, wouldn’t return anymore.”


But the fish are returning, since they can’t swim to the reservation anymore, the tribe is trucking them in. It is a long-term project. Sturgeon don’t mate until they’re at least twenty-five years old, so some tribal members won’t live long enough to know if their efforts have paid off. But if the tribe’s project and others like it are successful, then humans may claim credit for saving the fish once almost pushed to extinction. For the Great Lakes Radio Consortium, I’m Patty Murray in Green Bay, Wisconsin.

Annual Sturgeon Spawn

Northeast Wisconsin is home to one of North America’s largest sturgeon populations. Every Spring, those sturgeon swim north from Lake Winnebago to spawn. The fish are huge, prehistoric-looking creatures. Some of them are more than six feet long and weigh a hundred pounds. The Great Lakes Radio Consortium’s Nick Van Der Puy was there and has this report: