Monarchs Flying South

  • The shorter days are a signal to Monarch butterflies to migrate south. Some travel more than 2,000 miles to winter in Mexico. (Photo by Marty Davis courtesy of Monarch Watch)

Right now, hundreds of millions of monarch butterflies are making an incredible journey south to Mexico for the winter. They’re flying through Michigan for the next couple of weeks so you have a really good chance of seeing one if you’re outside. Steve Malcolm is a professor of ecology at Western Michigan University and an expert on monarch butterflies.

More about Monarchs

Monarch migration map

Transcript

Professor Malcolm, how on earth do monarch butterflies find their all the way to Mexico?


Steve Malcolm, PhD: Um, that’s a good question, we’re not absolutely certain how they do it. It may be that the very fast rates of decreasing day length change trigger physiological changes that cause them to move to the south. But quite how they orientate to Mexico we’re not absolutely certain.


RW: And these butterflies are famous for covering thousands of miles as they’re going on this migration. Is it just one insect making this journey?


Steve Malcolm: In the autumn, the adults that have bred in the Great Lakes region, southern Canada, as they’re flying south will be exploiting nectar resources so they can really build up their fat so by the time they get to the Gulf Coast they’re these huge, obese butterflies. They continue their migration to Mexico and spend five, even six months in Mexico and then they fly north in the spring, and maybe get as far north as central states like Kansas or even Iowa. Then they’ll basically die and it’ll be their offspring that continue the migration back to the Great Lakes region.


RW: There are some butterflies that look like monarch butterflies. How can you tell them apart?


Steve Malcolm: In the Great Lakes region, the viceroy is the only butterfly that looks very like a monarch. But the monarch has this typically lazy flight. It’s sort of a bold butterfly, you know, it just flies around and does its own thing. The viceroy it’s got the same basic coloration of being orange with black wing veins, but it has a more flick-y flight, it looks like a more nervous butterfly. It’s a little bit smaller than a monarch. If you look at it end on, it looks very flat somehow. Monarchs tend to look more like a flapping V if you like when they’re flying around in the environment.


RW: Where are the best places in Michigan to go if you want to see monarchs heading south?


Steve Malcolm: I personally like going to the Wickham music festival which was on this last weekend in the middle of Michigan, and lying on my back listening to the music watching the monarchs flying overhead. Typically you can lie there and watch a monarch flying over every minute. But also going to the shores of Lake Michigan is very good. Anywhere on the west side of Michigan, along Lake Michigan, if you walk on any of the beaches there you can usually see monarchs. They’ll arrive at the water’s edge and then they’ll pretty much fly south down the lakeshore.


RW: What can we do to help the butterflies out?


Steve Malcolm: I think it’s really good to do some butterfly gardening, particularly this time of year, to have nectar plants. It’s really helpful for the butterflies to have lots of food resources so they can build up their fat. Having a patch of milkweed, like common milkweed, or butterfly weed or the swamp milkweed. But I think it’s important to make sure they’re native milkweeds that belong in Michigan rather than some of the exotic milkweeds that are easy to grow.


RW: Well, thank you so much for your time.


Steve Malcolm: You’re very welcome.


RW: Steve Malcolm is a monarch butterfly expert at Western Michigan University.


That’s the Environment Report. I’m Rebecca Williams.

Native Pollinators in Trouble

  • Jeffrey Pettis says while honeybees are a concern because they pollinate crops, the wild plants that rely on native pollinators can be in trouble as well. (Photo courtesy of the US Fish and Wildlife Service)

Honeybees have been dying by the millions because of colony collapse disorder. But government officials say it’s not just the bees that are in trouble. Lester Graham reports.

Transcript

Honeybees have been dying by the millions because of colony collapse disorder. But government officials say it’s not just the bees that are in trouble. Lester Graham reports.

Jeffrey Pettis heads up the USDA’s bee lab in Beltsville, Maryland. He says there’s a lot of concern about honey bees because they pollinate crops. But he’s also really concerned about wild native bees, butterflies, bats that pollinate plants in the wild.

“The wild plants that rely on native pollinators can be in trouble as well. So, there’s certainly should be concern for all pollinators in addition to honeybees, which I like to think of as a major agricultural pollinator.”

Pettis says habitat destruction is hitting nature’s wild pollinators hard, but bats are also dying because of white-nose syndrome, a fungus that’s spreading, killing bats by the millions.

For The Environment Report, I’m Lester Graham.

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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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Forecasting Monarch’s Future in Warmer World

Every winter, millions of monarch butterflies migrate from backyards in North America to nestle in trees in Mexico. The weather conditions in the mountains there are perfect for the insect. But scientists say climate change could spell disaster for the species. The Great Lakes Radio Consortium’s Todd Melby has this report:

Transcript

Every winter, millions of monarch butterflies migrate from backyards in
North America to nestle in trees in Mexico. The weather conditions in the
mountains there are perfect for the insect. But scientists say climate change could
spell disaster for the species. The Great Lakes Radio Consortium’s Todd Melby has
this report:


The fir trees in central Mexico are ideal conditions for the monarch
butterflies of North America to spend the winter. The habitat there is cool
and dry.


“They are looking for a refrigerator.”


That’s Karen Oberhauser, a researcher at the University of Minnesota. She
Says the orange-and-black-speckled butterflies spend up to five months there
Before coming north again.


The new study was published in the Proceedings of the National Academy of
Sciences. It shows that the biggest threat to the monarch’s Mexican habitat
may be an increase in rainfall. She says that would cause the monarchs to freeze
to death.


“It’s worrisome to me that, in a sense, we humans are kind of conducting this huge experiment and
we don’t know the outcome.”


The long-term climate change could force monarchs to flutter off in search
Of new places to winter. She says if they fail, the results could mean the end
of a species.


For the Great Lakes Radio Consortium, I’m Todd Melby.

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Hanging on to Karner Blues

  • Karner Blue butterflies depend on wild lupine for survival. Lupine is the only plant Karner Blue caterpillars will eat. Photo by Ann B. Swengel, courtesy of the U.S. Fish & Wildlife Service.

Once, a postage-stamp-sized butterfly known as the Karner Blue was found all across the Great Lakes states, from Minnesota to New York. Today its population has declined by 99 percent. The Karner Blue’s last stronghold is in Wisconsin, where an unprecedented state-wide effort is underway to save it. The Great Lakes Radio Consortium’s Mary Losure reports:

B-T Corn Research Heads Into Field

In a recent issue of the journal, Nature, Cornell researchers released a
report claiming that pollen from a genetically engineered, or BT, corn
has a deadly effect on the monarch butterfly. But industry
representatives criticized the results, saying the lab-work didn’t
duplicate a real-life scenario. So now, Cornell scientists are heading
into the field for more research. The Great Lakes Radio Consortium’s
David Hammond has more: