The Challenge of Managing Fragmented Forests

In the Great Lakes states, many of the original forests were cut down. They were cleared for homesteading, farming, and for the wood that fueled the age of steam. But over the past several decades, some of the forests have been growing back. Many of the new forests are confined to small patches or woodlots surrounded by farm fields. These woodlots are small havens for animals. But some foresters, biologists, and environmental groups are concerned that those forests are simply too small and too fragmented. The Great Lakes Radio Consortium’s Cristina Rumbaitis-del Rio prepared this report:

Transcript

In the Great Lakes States, many of the original forests were cut down. They were cleared for
homesteading, farming, and for the wood that fueled the age of steam. But over the past several
decades, some of the forests have been growing back. Many of the new forests are confined to
small patches or woodlots surrounded by farm fields. These woodlots are small havens for many
animals. But some foresters, biologists, and environmental groups are concerned that those
forests are simply too small and too fragmented. The Great Lakes Radio Consortium’s Cristina
Rumbaitis(rum-bite-us)-del rio (del-rhee-o) prepared this report:


(Natural sounds – walking through leaves underneath) & Thomas Grubb talking:
“This little woodlot is large enough to house one pair of downy woodpeckers and one pair of
white breasted nuthatches.”


Thomas Grubb is a Biology Professor at Ohio State University. Instead of lecturing to a classroom
today, he’s strolling through a small, private woodlot next to a cornfield in central Ohio. This is
one of the study sites where he looks at how forest fragmentation affects woodland bird species.


He says just as in many areas of the Midwest, Ohio’s forests are highly fragmented because
instead of having the forest concentrated in one big area, the forests are carved up into small
patches, scattered throughout a largely agricultural landscape. While 90% of Ohio was covered
with forest before European settlement, now less than a third of the state is considered forested.
And according to Grubb, this part of Ohio has even less forest.


“This plot is about 3% forested and that’s not much forest. This landscape is probably as little
forested as any you’re likely to find.”


Grubb and his students are working with woodlot owners to see if the size of a woodlot affects
the number of birds living there and their survival. He says bird survival is better in larger
woodlots than in smaller ones.


“One of the things we think is happening in these small woodlots, these permanent resident birds
that are there all winter- they can’t get out of the wind, and so they have tremendously high
metabolic rates trying to stay warm.”


Smaller woodlots may be colder than larger ones because there’s fewer trees to block the wind.
Smaller woodlots also have less food for birds, and in the winter birds may starve trying to get
enough food to stay warm.


(Natural sounds of leaves and birds)


“Oh that’s a Carolina Wren.”


Forestry officials, scientists, and environmental groups agree forest fragmentation is one of the
most serious problems facing Ohio’s forests. Fragmentation is a problem for a number of reasons
beyond the fact that it represents a loss of forest habitat. According to Ohio State University
Ecologist, Ralph Boerner, the smaller a forest patch is, the fewer number of species that can live
there.


“The smaller a forest patch, the less diverse it is. And you particularly lose species that need
large areas in which to gather food.”


Boerner says smaller patches may also have a harder time recovering from disturbances – like an
insect outbreak or a tornado.


“We also believe there is a link between how diverse an ecosystem is and how stable it is in the face of disturbnace, so when you lose diversity there’s the potential to lose stability, lose the ability to bounce back
from disturbance.”


Breaking up the forest into patches also isolates animal and bird species that can’t or won’t cross
agricultural fields to get from one forest patch to another, and that means less genetic diversity
because they can’t mate with animals outside of their forest patch. So some woodlots are just too
small for certain species to survive.


Fragmentation also makes managing forest land more difficult. Most of Ohio’s forested land is
privately owned. Ohio Division of Forestry official, Tom Berger, says this makes managing
almost an impossible task.


Well, you’ll have 10 people and they’ll have 10 different views on how to manage it or what’s
valuable to them and they all have that right.”


Division of Forestry officials can give landowners advice, but they can’t tell a landowner what
their priorities should be. Berger says this often means neighboring patches of forest are managed
for completely different interests. Berger wishes he had more tools at his disposal to get land
owners to manage their land collectively.


“I wish we could put together some programs or some incentives, monies available through the
state or federal government that would really encourage landowners to work together to form
blocks or units that would be managed in the same way.”


Managing isn’t the only challenge. Berger says keeping the land at least partially forested is
becoming a problem as people choose to build homes in woodlots, particularly in areas near
cities.


“Not only is the woods scattered that we have fragmented, but a lot of them continue to
disappear too, especially in the urbanized areas in Columbus and around the state.”


Ohio State University Biologist, Thomas Grubb, says there are may reasons for protecting
woodlots, but his favorite reason is because it’s a pocket of nature in a sea of developed land.


“This is worth preserving just because it’s like it is and we ought to just leave it alone. This enriches our lives.”


The average woodlot size in Ohio is 20 acres, and it changes hands frequently – every seven years on average. The small size and the quick turnover make it nearly impossible for the state to
encourage owners to establish any kind of useful management practices. That means there’s little
to be done to help keep the forests from further deterioration.


For the Great Lakes Radio Consortium, I’m Cristina Rumbaitis-del Rio.

Endangered Mussel Rides to Renewal

  • Biologists release bass, gills laced with Higgin's Eye Pearly Mussel larvae, into the Mississippi River. Photo courtesy of the Minnesota Department of Natural Resources.

Up and down the Mississippi River, people once collected tons of mussels for the pearl button industry. Factories stamped out pearl buttons from the shells, sometimes wiping out 50,000 tons of mussels annually in the early part of the last century. In recent years, the biggest threat to local mussel species has come from the zebra mussel. That invasive species came to North America in the ballast water of ships and has since disrupted many local ecosystems. Today, there’s a new effort underway to bring back local species like the Higgin’s Eye Pearly Mussel, and it’s in an unlikely place. The Great Lakes Radio Consortium’s Todd Melby has this report:

Transcript

Up and down the Mississippi River, people once collected tons of mussels for
the pearl button industry. Factories stamped out pearl buttons from the shells,
sometimes wiping out 50,000 tons of mussels annually in the early part of
the last century. In recent years, the biggest threat to local mussel species
has come from the zebra mussel. That invasive species came to North America in
the ballast water of ships and has since disrupted many local ecosystems. Today,
there’s a new effort underway to bring back local species like the Higgin’s
Eye Pearly Mussel. And it’s in an unlikely place. The Great Lakes Radio Consortium’s
Todd Melby has this report:


Urban areas like Minneapolis-Saint Paul might seem like an unusual
location to boost the population of an endangered species.


But it’s here, below a busy bridge that spans the Mississippi River, that
biologists are searching for a safe place for their project. Divers have
just come up from the bottom of the river with a few mussel specimens.


“Well, we’ve got Big Toe, Maple Leaf, Three Ridge. Good enough I think.”


That’s Mike Davis rattling off the names of mussel species. Davis is
a biologist with the Minnesota Department of Natural Resources. The fact that
some mussels live in this part of the river makes Davis think that this
might be a good spot for the Higgin’s Eye. The Higgin’s Eye, which has an olive-
colored shell, has been languishing on the Endangered Species List since
1976.


Just two decades ago, this part of the river suffered from sewage runoff. The river is cleaner now and some mussels have returned. But not the Higgin’s Eye. And that has Roger Gordon worried. He’s a biologist with the U.S. Fish and Wildlife Service.


“They function as the kidneys of the river, more or less. They siphon everything that
goes through the river. They are a very good indicator species if we have a problem in the environment. They are usually the first species to get hit hard and disappear.”


For the past decade or so, it’s been the zebra mussel that’s been hitting the Higgin’s Eye. But the zebra mussel hasn’t made it to this part of the river. That’s why biologists are on a small flotilla of boats on this morning with 800 large-mouth bass. The bass and the Higgin’s Eye have a strong connection. Attached to the gills of those bass are thousands of Higgin’s Eye larvae.


“Right now, we’re counting fish in the cage. We have a known number of fish, 25 in
this case, that we’re going to place in these cages. And hopefully over the next several weeks, they’ll drop off and we’ll have clams in the river.”


Melby: “You’re putting them in the bucket?”


“Right now we’re putting them in a bucket and placing them in the cage over the
side of the boat.”


(sound of buckets banging and water sloshing)


The bass are put in cages so they don’t swim somewhere that’s not a good home for the Higgin’s Eye. In the wild, adult females mussels shoot embryos at unsuspecting fish swimming overhead.


“The larvae have a chemo-receptor in them. When they touch flesh, they actually shut. It’s a one-shot deal. If that fish clamps on a fin or an eyeball or a lip, it’s a no-go. He’s not going to develop. But if he’s lucky, and he just happens to be going through a gill arch of a fish and it’s the right fish, the right species of fish and the right size fish, it
will shut on that gill.”


But the Higgin’s Eye population is too low to leave to chance.


(Bubbling sounds of fish hatchery)


So Gordon and his colleagues bumped up the number of mussel larvae
per fish here at a federal fish hatchery in Genoa, Wisconsin. Instead of just a
few larvae per fish, the bass dropped into the Mississippi have several dozen
larvae attached to their gills.


That prep work took place inside the “Clam Shack,” which is really
just a metal pole barn that biologists built themselves.


“We didn’t have any money to do this. We scraped up and saved up at the end
of the year. We had seven or eight-thousand dollars. The hatchery guys just got together and built this little building.”


Since beginning their work two years ago, they’ve added approximately
12,000 mussel-rich fish to rivers in Wisconsin, Illinois, Iowa and Minnesota.


“We’re probably going to have to build another little building
like this. But we’ll scrape along and do what we can.”


Back on the river, Mike Davis of the Minnesota DNR calls the return
of the Higgin’s Eye historic. But with the zebra mussel closing in on native
mussel species like the Higgin’s Eye, he’s also a bit wistful.


“The former dead zone of the Mississippi may become
one of the last refuges for the Mississippi’s mussel species.”


In September, divers return to that same spot to check on the Higgin’s
Eye. They hope to find thousands of young clams nestled safely in their new
home. For the Great Lakes Radio Consortium, I’m Todd Melby.

Threat Increasing From Invasive Fish

A spiny fish that can hunt in the dark has invaded Lake Michigan. The foreign fish is known as the Eurasian ruffe. As the Great Lakes Radio Consortium’s Annie MacDowell reports, biologists fear the ruffe could harm the lake’s yellow perch population:

Transcript

A spiny fish that can hunt in the dark has invaded Lake Michigan. The foreign fish is known as the Eurasian ruffe. And as the Great Lakes Radio Consortium’s Annie MacDowell reports, biologists fear the ruffe could harm the lake’s yellow perch population:


Experts say the ruffe is originally from the Black and Caspian seas, and it’s an
efficient little machine. It lays enormous numbers of eggs and has no predators because of its spiny skin. Gary Lamberti is a professor in the department of biological sciences at the University of Notre Dame.


He says the ruffe are depleting the yellow perch’s food supply.


“The Eurasian ruffe are specialists on that food, that is they eat that food all the
time. And those are the worms and aquatic insects that are found at the bottom of
the lake. That’s what ruffe eat and that’s also what perch eat at a certain stage of
their lives. But ruffe do it all the time and they do it better.”


Lamberti says the yellow perch’s population is already declining in the Great Lakes,
probably due to competition from many invasive species.


The ruffe could be another blow to the commercial fishing industry, as yellow perch
are widely harvested for food and are a favorite among sportsmen.


The Eurasian ruffe probably migrated from Lake Superior, where they were first
discovered in the 80’s.


For the Great Lakes Radio Consortium, I’m Annie MacDowell.

Too Much Success for Canada Geese?

  • Canada Geese take flight. Photo by Wyman Meinzer, courtesy of the U.S. Fish & Wildlife Service

Canada Geese are about as common as the green lawns they like to hang out on. But at one time they’d almost disappeared from the region. Thanks to successful wildlife management efforts, the goose is back, and now the question is how best to manage a success story that some say has been too successful. The Great Lakes Radio Consortium’s Dan Gunderson has more:

Transcript

Canada Geese are about as common as the green lawns they like to hang out on. But at one time they’d almost disappeared from the region. Thanks to successful wildlife management efforts, the goose is back, and now the question is how best to manage a success story that some say has been too successful. The Great Lakes Radio Consortium’s Dan Gunderson has more.


In 30 years, the giant Canada goose was on the verge of extinction, but the species has made a comeback that amazes biologists. There were just about enough for a gaggle when humans stepped in to help in the late 1960’s, now numbering in the millions today, the goose is a wildlife management success story that won’t stop.


“We’ve spent millions and millions of dollars to bring the population back.
Now it’s high and it’s eating everything in sight.”


Standing on the edge of a waist high soybean field on his Minnesota farm, Chad Jetvig points to a slough about a quarter mile away. It’s obvious where geese feasted on tender young soybean plants early this summer, leaving large bare spots in the field.


Jetvig says he’s always accepted some crop loss from geese as a part of farming among the prairie potholes of western Minnesota, but he says the amount damage is no longer acceptable.


“I would say in the past two years in particular, but it’s been getting worse each year, we’ve started to see huge areas. Just on this one single farm at two hundred acres that’s over 40 thousand dollars right just out of our pocket. That’s a lot of money.”


And thousands of farmers in the Midwest and Northeast U.S. have similar stories.


This year and last, Chad Jetvig has gotten a permit to shoot geese eating his crops, but he says it’s an exercise in futility.


“We came out here and shot one time and the next time you even drive by they’re gone. They’d even know the color of the pickup. If this one blue pickup we’re using came around, they seen that thing, whoosh, they’re gone.”


Only to return as soon as the coast is clear. Those keen survival instincts are one reason for the goose population explosion. There’s also plentiful food provided by farmers like Chad Jetvig, and lots of wetland nesting sites.


There are an estimated 2 million giant Canada geese in the upper Midwest and Northeast that’s far more than biologists like Minnesota Department of Natural Resources, goose expert, Steve Maxson think is ideal.


“I think a lot of biologists are wondering just how high this population can go. It’s already exceeded their wildest dreams I think and it seems even in the face of intense hunting pressure to be increasing in most areas. I guess the bottom line is we just don’t know how high this population can get.”


Biologists rely on hunting to keep many wildlife populations in check, and the Canada goose harvest has steadily increased along with the population. But Maxson says simply allowing hunters to shoot more birds is not the answer. The birds quickly learn how to avoid hunters. Then there’s the eastern prairie goose that nests in northern Canada and migrates through many states in the region. The eastern prairie goose population is much smaller and less robust than the giant Canada, and biologists fear expanded hunting could destroy the species.


The U-S Fish and Wildlife Service draft environmental impact statement due out this fall will offer several population control alternatives. They range from no action, to targeted hunting in areas where geese are in conflict with humans, to extreme measures such as, destroying nests and eggs. Steve Wilds is the Fish and Wildlife Service regional migratory bird and Chief. He says it’s critical a workable plan come out of this process. If not, he fears future management decisions will be political, not biological.


Wilds says the future of the giant Canada goose is at stake.


“So that they’ll continue to be recognized as a tremendous, beautiful part of our natural landscape and yet not something that’s going to be doing so much damage people start thinking of them as vermin rather than really neat critters.”


The Fish and Wildlife plans to take a public input on its goose management plan early next year. Steve Wild says it will be at least a year before any final decision is made on how the Canada goose populations will be managed in the future. For the Great Lakes Radio Consortium, I’m Dan Gunderson.

Eco-Cows Munch on Invasive Plants

  • Researchers are finding that Scottish Highland Cattle, such as these Rockhill Red Cows, have an appetite for many types of invasive plants. Photo courtesy of Marv & Ann Rockhill.

Cattle that love to eat thorny shrubs and nasty weeds are proving they can clean up areas infested with invasive plant species. The Great Lakes Radio Consortium’s Mary Jo Wagner has this report:

Transcript

Cattle that love to eat thorny shrubs and nasty weeds are proving they can clean up areas infested with invasive plant species. The Great Lakes Radio Consortium’s Mary Jo Wagner reports.


For years, land managers have been trying to find better ways to control particularly troublesome plants. Invasive species such as multi-flora rose, prickly ash and wild parsnip used to be held in check by natural fires, or grazing by bison and elk. But ever since wildfires have been mostly controlled, and elk and bison populations have plummeted, many invasive species in the Great Lakes region have been growing out of control. So researchers have been looking for other ways to fight these invaders. At the University of Wisconsin, researchers have been testing Scottish Highland cattle on some fields containing invasive species. Consultant Martha Rosemeyer says the preliminary results look promising…


“One of the things we’ve found out by following the cattle is they really like wild parsnip when it’s young. Out of a field of grass they’ll identify and hone in on the wild parsnip and eat the whole patch of it.”


One of two farms testing the cattle’s weed eating potential is owned by Peter Rathbun. He says on one of the test plots, the parsnip was so high and thick, biologists wouldn’t go in to take samples.


“I was a little concerned, well are the cows going to go in and eat it and get sick, but they went in and ate it and they loved it.”


Rathbun has various weed and brush problems or “junk” as he calls it on 120 acres, including prickly ash, hawthorn, gooseberries and other plants that produce large thickets. He was one of the first farmers in Wisconsin to start raising the highland cattle several years ago and now has around forty animals eating weeds on half his farm. His goal is to return some o the land to its original oak savannah status. So far on his fifteen test plots with and without cattle, the results of grazing Scottish cattle are positive.


“It’s so wonderfully obvious what’s happening because here’s three strands of electric fence. On one side you can walk right through the woods…its no problem – you can see everything there. On the other side it’s dense, you don’t even want to think about walking through it. And this is only after 2 rotations.”


Rotating means moving groups of up to nine cattle around on once-acre test plots. The cattle spend two or three days on select plots each month throughout the summer. Martha Rosemeyer says researchers were interested in the breed of cattle because in Europe, they’re referred to as “eco-cows.” That’s because of their unique ability to eat plants that have inch-long thorns.


“They’ve got really tough tongues – they wrap them around these and pull – so they pull these things up like prickly ash leaves off and aren’t really bothered by thorns. They actually like thorns to rub and scratch…they’ll lean on things and scratch and they’ll break them and change the vegetation in that way too.”


Peter Rathbun says it didn’t take long for his cattle to tackle a patch of prickly ash after the gate into one test plot was opened.


“They ran over to it and started eating the actual bush. And I loved to see the reaction of some of the graduate students who’ve been working on this for a very long time. In their heart of hearts they really had some doubts whether the animals were really going to like to eat the junk.”


Once results are in by the summer of 2003, consultant Martha Rosemeyer says researchers may have a better idea of how effective the cattle will be at permanent eradication of unwanted plants.


“Certainly if you knock down a plant by taking off it’s above ground vegetation a number of times, it weakens the plant and it eventually will die. That’s what we’re hoping will happen but we’re not sure we need to test this and see the results…it’s speculation at this point.”


By comparison, Rosemeyer says on Department of Natural Resources land, a few test pilots were grazed and burned earlier this year to compare the weed control with the Highland cattle. It turned out that combination was too destructive and the burning was discontinued.


Meanwhile, not only do these animals eat through the bad stuff, but they also provide great hamburgers. Rathbun sells the meat as a low fat, very tasty source of protein.
For the Great Lakes Radio Consortium, I’m Mary Jo Wagner.

Controlling the Lamprey

The assault against sea lampreys in the Great Lakes continues, as biologists from the U.S. Fish and Wildlife Service are combing the waters of West Michigan’s Lincoln and Pere Marquette rivers this week. The Great Lakes Radio Consortium’s Matt Shafer Powell has more on the government’s on-going attempts to keep this creature under control:

Biologist Fosters Bald Eagle’s Return

In the 1960’s, the bald eagle was in trouble. There were only about 4
hundred birds living in the U-S And in some states, pollution had wiped
them out altogether. But the bald eagle has made an impressive comeback.
The U-S Fish and Wildlife Service recently announced plans to remove it from
the endangered species list. As the Great Lakes Radio Consortium’s Karen
Kelly reports, it’s good news for the scientists who fought to save this
bird:

Are Peregrine Falcons Still Endangered?

In the 1960’s, the peregrine falcon population was virtually wiped out.
Today, there are about 2 hundred pairs living east of the Rocky
Mountains. The federal government says the species is no longer in
danger. But as the Great Lakes Radio Consortium’s Karen Kelly reports,
biologists who work with these birds disagree: