Tag: larvae

Pigs Root Out Evil Bugs

  • Apple grower Jim Koan has discovered that baby pigs are best for taking care of fallen wormy apples in his orchard. He says they have very tender noses. The adult pigs like to root around in the dirt and tend to tear up the orchard. (Photo by Rebecca Williams)

There are a lot of insects that love to eat
apples. A harmful insecticide that kills some of
those pests is being phased out. So farmers are
looking for other solutions. Rebecca Williams visits
an apple grower who’s counting on pigs to get some
help with his pest problem:

Transcript

There are a lot of insects that love to eat
apples. A harmful insecticide that kills some of
those pests is being phased out. So farmers are
looking for other solutions. Rebecca Williams visits
an apple grower who’s counting on pigs to get some
help with his pest problem:

(farm animal sounds – turkeys, etc)

The spring rains have started, and at Jim Koan’s pig pen that means mud.

(sound of shoes squishing in mud and piggy snorts)

Of course, these pigs don’t really seem to mind that.

“These Berkshires, you can see, are really friendly, they’re just coming
right up to you.”

Jim Koan really likes his pigs. That’s because he’s hoping the pigs will
take care of one of his worst pests. It’s a beetle called the plum
curculio. In early spring the beetles lay eggs in the little green apples.
The larvae hatch and eat the apples from the inside out.

Then the tree drops the bad wormy apples on the ground. And the worms just
keep on eating.

For a long time, farmers used an insecticide called azinphos-methyl to kill
the beetles. But the Environmental Protection Agency is phasing it out.
That’s because the EPA says the pesticide is very toxic to some wildlife and
it can make farm workers sick.

Jim Koan hasn’t used the pesticide for 10 years, ever since he became an
organic grower. So for years now he’s been trying to find a perfect
predator to stop the beetle larvae.

The chickens were too lazy. Hawks ate the guinea fowl that he tried.

So, finally, Koan says he had a flashback. His grandpa used to have hogs in
the orchard.

“When I would climb up to go up in the tree in the summertime to get a green
apple to eat all the hogs would come running over there and my granddad
always told me you stay away from those hogs they’ll eat you up! I’d be
really scared and be up there for an hour or two until the hogs left again.”

(laughs)

Koan says he knows now that the hogs were just hoping for a snack. So last
year he decided to buy some hogs and see if they would eat the wormy apples
on the ground. He says baby pigs worked best.

“And they’d just go up one row gleaning it, kinda like little vacuum
cleaners (makes sucking sound) and suck up all the apples!”

Koan says the baby pigs ate 98% of the fallen apples with beetle
larvae in them. But he still needed to know that the beetles were actually
gone, so they wouldn’t come back to attack his apples next year.

That job
was up to researchers at Michigan State University. Koan says they fed a
mix of beetle larvae and apples to pigs on campus.

“Then they put diapers on the hogs – truly, diapers!! It was unbelievable.
They took special superglue and velcroed it on their butt so then when they
defecated they caught all that. Then they took these poor students and made
them go through there and wash all that and look for worms.”

Koan says out of 200 worms that were fed to the pigs, they only found one
worm at the other end. That means, so far it looks like pigs are a
pretty good predator.

But the researchers don’t want to let pigs run wild – just yet. David
Epstein is the lead researcher on the project.

“Jim and I are scheming all the time. I have great expectations that this
could be a good management tool in the future but we have to figure out how
to do it properly.”

Epstein says they need to make sure the pigs don’t cause any contamination
problems. Something like E. coli. He says so far there isn’t any
evidence of that, but it’s the kind of thing you have to be sure about.

If this all goes well, the farmer and the scientist will be writing a book
together. It’ll be sort of a self-help book: getting pigs to take care of
what’s bugging you.

For the Environment Report, I’m Rebecca Williams.

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Freshwater Mussels Not Happy-As-Clams

Researchers have been finding trace amounts of pharmaceuticals in rivers and lakes. Now, a new report suggests that the presence of Prozac in water bodies might be endangering freshwater mussels. Celeste Headlee has details:

Transcript

A new report suggests that the presence of Prozac in natural water systems can increase
the risk of extinction for freshwater mussels. Celeste Headlee has details:


Many freshwater mussel species are already highly endangered. Experts say about 70
percent of the 300 known species of mussel in North America are extinct, endangered or
declining. Authors of the new study say even trace amounts of anti-depressants like
Prozac are dangerous to mussels because they interfere with reproduction.


Prozac and other prescription medications are flushed into sewer systems and then
released into rivers and streams. Researchers placed female mussels carrying larvae into
tanks with various concentrations of Prozac. Within two days, all of the mussels had
prematurely released their larvae, which then died.


The authors of the study say new wastewater treatment procedures might have to be
developed to filter out prescription and over-the-counter drugs before they reach
waterways.


For the Environment Report, I’m Celeste Headlee.

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Pheromone to Help Control Lamprey?

  • The sea lamprey drastically changed the Great Lakes ecosystem. (Photo courtesy of the Great Lakes Fishery Commission)

Researchers say they’ve discovered a migration pheromone
in sea lamprey. It’s a natural attractant that could boost efforts to
control the invasive parasite. The Great Lakes Radio Consortium’s
Stephanie Hemphill reports:

Transcript

Researchers say they’ve discovered a migration pheromone in sea lamprey. It’s a natural attractant that could boost efforts to control the invasive parasite. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:


Each lamprey can kill forty pounds of fish in its lifetime. Managers use a pesticide to keep the lamprey numbers down, but it’s expensive, and sometimes it kills other fish.


University of Minnesota biologist Peter Sorensen says he’s isolated a chemical signal put out by lamprey larvae. The larvae live in streams, and the signal apparently tells adult lamprey that the stream is a good place to lay eggs.


“We’ve got a cue that’s very powerful, very safe, we don’t need very much of it, and it can control the distribution of the lamprey in a way that other things can’t.”


Sorensen says the pheromone can be used to corral lamprey into areas where they can be trapped or treated with pesticide. The pheromone is being tested in a river in Michigan.


For the GLRC, I’m Stephanie Hemphill.

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Searching for Salamanders at Old Nuke Site

  • Salamanders are a good indicator of wetland health. (Photo courtesy of the Washington Department of Fish and Wildlife)

Government workers are slogging around in man-made wetlands.
looking for salamanders. Back in the 1950’s, the United States government
selected a plot of land to be the home of its newest uranium processing plant.
Since the end of the Cold War, the now-closed nuclear processing plant has
been undergoing the long and arduous task of returning to its natural wetland
state. The Great Lakes Radio Consortium’s Tana Weingartner reports on the search for salamanders at the site, and why
their presence is so important:

Transcript

Government workers are slogging around in man-made wetlands looking for salamanders. Back in the 1950’s, the United States government selected a plot of land to be the home of its newest uranium processing plant. Since the end of the Cold War, the now-closed nuclear processing plant has been undergoing the long and arduous task of returning to its natural wetland state. The Great Lakes Radio Consortium’s Tana Weingartner reports on the search for salamanders at the site, and why their presence is so important:


It’s a cold, windy day in late March as specialists from the Ohio Environmental Protection Agency head out to check their traps at the Fernald Nuclear Plant. The 1050-acre facility sits in a rural area just 18 miles north of Cincinnati. Although the EPA is in charge of cleaning up the uranium contamination here, today they’re on a different mission. Today they’re hunting salamanders.


“Salamanders basically are a sign of an established wetland usually, and in this case would show that we put a wetland in a location where salamanders need additional breeding habitat.”


In other words, Schneider says the presence of salamanders indicates the first level of success for these manmade wetlands. The wetland project is one of several ways the EPA is ensuring Fernald is properly restored to its natural state.


“Well, we’re looking forward to the day when we get the site cleaned up, and it can be like a land lab, and people can bring kids out here and do environmental education on the importance of wetlands, and it’s going to make a great contrast with what used to be here and the environmental contamination with the environmental benefit the facility is providing down the road.”


Today, the site is 70 percent certified clean, and officials expect to finish the cleanup by June 2006. Creating healthy wetlands full of insects, amphibians and salamanders is one of the first steps to success.


“So the method here is to set ten traps equidistant, hopefully, around the perimeter of the wetland. And they’re passive traps, whereby animals that are moving over the course of the 24 hours or so that the traps have been in, will bump into the traps and it’s a funnel that directs them into the center part of the trap, and they’re held in there until we release them.”


(splashing sound)


Schneider and his team laugh and joke as they pull the traps up by brightly colored ribbons. Train horns and construction noises mix with bird calls – one a reminder of what has been, the other a sign of what’s to come.


“That’s probably a one-year-old bullfrog there and then these big guys are dragonfly larvae and these other guys are back swimmers. Mayfly larvae and dragonfly larvae are both good indicators of high water quality.”


The third pond, or vernal pool, turns up 46 tadpoles and a tiny peeper frog, but no salamanders.


(truck door slams)


So it’s back in the truck and on down the dirt road to where several more wetland pools sit just across from the on-site waste dump. That dump will be Fernald’s lasting reminder of its former use. These pools are younger and less established, but they do offer hope. Last year, adult salamanders were found in the one closest to a clump of trees.


Each spring, as the snow melts away and temperatures rise, salamanders venture out in the first 50-degree rain to begin their search for a mate. Schneider had hoped warm temperatures in late February and early March prompted “The Big Night,” as it’s known.


“So, no salamanders today?”


“No salamanders today. I think we learned a little bit about the difference between wetlands that are three years old. We saw a lot more diversity in the macroinvertebrates, the insect population, than we have down here.”


Perhaps the salamanders haven’t come yet, or maybe they have already come and gone, leaving behind the still un-hatched eggs. Either way, the team will check back again in April and a third time in late May or June.


“And we have high hopes, high hopes, high apple pie in the sky hopes. That’s the kind.”


(sound of laughter)


For the GLRC, I’m Tana Weingartner.

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Little Fish, Big Fish: Which to Keep?

The common practice of throwing the little ones back could be harming future fish populations. The Great Lakes Radio Consortium’s Christina Shockley reports:

Transcript

The common practice of throwing the little ones back could be harming future fish populations. The Great Lakes Radio Consortium’s Christina Shockley reports:


Anglers and commercial fisheries are often only allowed to take fish that are larger than a certain size. So the smaller fish are left to reproduce. And researchers say that means their offspring will also be smaller, and not as healthy.


David Conover is a marine scientist at Stony Brook University. He says the larger fish are vital to the overall health of their species.


“The eggs that these big, old females produce tend to be of higher quality. The egg diameters may be a little larger, the yolk that is supplied to the eggs seems to be more rich, the larvae hatch at a larger size, they have a higher survival.”


Conover says fish populations can be harmed in as little as three or four generations. And it can take much longer for a population to rebound – if it can at all.


He says possible solutions could include different rules that protect larger fish, and new limits on where fish can be harvested.


For the GLRC, I’m Christina Shockley.

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Essay: Tuning in to Urban Frogs

  • Ed Herrmann tries to hear some frogs through the traffic near the Rouge River. (Photo by Ed Herrmann)

Each Spring, thousands of people spend their evenings listening to frogs and toads. It’s not just for fun. They’re helping assess the water quality of rivers and wetlands around the country. The Great Lakes Radio Consortium’s Ed Herrmann joined the search for amphibians, and has this essay:

Transcript

Each Spring, thousands of people spend their evenings listening to frogs and toads. It’s
not just for fun. They’re helping assess the water quality of rivers and wetlands around
the country. The Great Lakes Radio Consortium’s Ed Herrmann joined the search for
amphibians, and has this essay:


I’ve always enjoyed being outside and listening to nature. Recording nature sounds is a
hobby of mine. So when I saw an ad asking for people to listen for frogs and toads, I
thought, “All right. Beats watching campaign commercials.”


I called up Friends of the Rouge…(that’s a local group dedicated to helping out the Rouge
River watershed) and a few days later I got a package in the mail. It was full of maps and
information, and had a CD with the songs of the local frogs and toads. I studied my area,
and found some good looking wet spots where I thought they might live.


I memorized the sound of the Wood Frog (sound), Chorus Frog (sound), Spring Peeper
(sound), and American Toad. Then, on the first night when the temperature and wind
conditions were just right, I headed out to hear some frogs.


(sound of traffic roaring by)


I don’t know what I was thinking. This is suburban Detroit, not exactly a wildlife refuge.
In fact, the only animal I see is a rabbit dodging traffic. And the only thing I hear is…
(more traffic sound)


The Rouge River flows into the Detroit River and then Lake Erie. It used to be one of the
dirtiest rivers around, mainly from all the industry down by the mouth. That problem is
more or less under control but now there’s a larger one.


If you look at a map from the 1970s, you see miles of wetlands, small farms and
orchards. Today you see nonstop subdivisions and shopping malls. It might seem like
progress to you, but for the river, the constant barrage of fertilizers, pesticides, soap and
other chemicals that everybody uses to keep their suburbs looking pretty is a lot worse
than an occasional dose of battery acid from a factory. Also having acres of concrete
instead of wetlands means there’s nothing to soak up and filter the water, which means
after a big rain, it floods. It’s obvious this river needs some help.


(sound of river)


In 1998, volunteers began surveying the frogs and toads in the Rouge watershed. These
creatures were chosen because they sing, so they’re easy to track. The reason they’re
good indicators is that, like other amphibians, they absorb water through their skin. That
means they get poisoned by everything that we in the civilized world pour into the water.
Plus, their eggs hatch in water and their larvae (the tadpoles) live in water. It’s pretty
simple: if the water is good, there’s plenty of frogs and toads. If not, they disappear.


So, night after night, I’m out there listening. Listening in the dark. Listening hard.


Not a peep.


I’m beginning to think that the price of all these well-manicured lawns is a silent spring.
Then finally one night, (sound of American toads) the good old American toad! All
right, it is the most common species around, but at least it’s a start.


(sound of chorus frogs and green frogs)


A few weeks later, I join a group at a “mitigated” wetland. That means that when a
developer decided that a real wetland would be the perfect place to build condos and a
golf course, the government said, “Sure, go ahead. Drain it. Just be sure to dig a hole
over here and fill it with water.” Now, five years later, some frogs have moved in and
seem to be fine.


But they still have a little problem…


(jet roars overhead, followed by a few green frogs)


Ah, location, location. This new wetland is right
next to the airport.


Now, the reason these frogs sing is to attract a mate. So if nobody hears them, there are
not going to be any tadpoles to make next year’s frogs. In order to survive, they need not
only to sing, but to be heard.


For the Great Lakes Radio Consortium, I’m Ed Herrmann.


(frogs fade out)

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Pitfalls of Spraying for West Nile Virus

  • The Culex pipiens quinquefasciatus mosquito - one of the mosquitoes responsible for the transmission of West Nile virus. Photo courtesy of the USGS.

The West Nile virus has claimed 28 lives and at least 550 people have been infected in the nation so far this summer. And evidence of the virus has already been found in 41 states. The carriers of the virus, mosquitoes, have been a concern and a nuisance for public health officials. Many citizens are demanding more visible action on the officials’ part to get rid of the bad bugs…like spraying chemicals to kill adult mosquitoes. The Great Lakes Radio Consortium’s Annie MacDowell reports:

Transcript

The West Nile virus has claimed 28 lives and at least 550 people have been infected in the nation so far this summer. And evidence of the virus has already been found in 41 states. The carriers of the virus, mosquitoes, have been a concern and a nuisance for public health officials. Many citizens are demanding more visible action on the officials’ part to get rid of the bad bugs…like spraying chemicals to kill adult mosquitoes. The Great Lakes Radio Consortium’s Annie MacDowell reports:


You might not expect to find a breeding ground of controversy in the suburbs, but
then again, you wouldn’t expect to find an exotic disease breeding there, either.
With the West Nile virus threatening any place that has mosquitoes…which is almost
anywhere…people are fighting over whether to spray or not to spray.


Spraying means releasing pesticides into the air to kill adult mosquitoes.
Pro-sprayers say the threat of West Nile virus necessitates this chemical
treatment. But some people who live in spraying districts are worried about the
possible dangers of the pesticides. Dr. Kim Stone is the Executive Director of the
Safer Pest Control Project in Chicago. As we walk around a nature preserve, she
tells me they’ve started spraying in her neighborhood and she’s worried about her
kids. Passing the pond and a grove of trees, she says the pesticides could kill fish
that eat mosquito larvae and birds that eat the adults. But she’s more concerned
about their possible threat to humans.


“I believe that the health impacts of the pesticides are a greater danger than the health impacts of West Nile virus. A local hospital had seen many people who thought that they had West Nile virus, came in with headache, nausea, and the hospital said that they did not have West Nile virus, but suspected that it might be related to the pesticides, because it was the morning after pesticides were sprayed in those neighborhoods.”


Stone recommends a different form of mosquito abatement…larvaecide.
Larvaecide is a preventative form a treatment that kills mosquito larvae before they
hatch. Pellets of larvaecide are dropped into lagoons, or a blower is used to spread
granules over the water. The chemicals are less toxic, she says, and they’re
species-specific. That means they won’t kill other animals. Dr. William Paul is with
the Chicago Department of Public Health. He says the city of Chicago hasn’t started
spraying because larvaecide is much more effective.


“We would really, in terms of mosquito control, want to focus on the long run,
breeding sites, and larval breeding sites, because that’s in the long run what’s going to be more effective. Using sprays for adults to kill the northern house mosquito… it’s challenging, you need tightly spaced applications of the product. And it’s not just a going up and down the streets kind of thing.


But spraying is a more visible treatment than larvaecide. Paul says people like to
see their government doing something to combat the mosquitoes. It makes them
feel better, he says. Other government officials can relate. Dr. Kiahn Liem has
been the head of the South Cook County Mosquito Abatement District in the Chicago area for 28 years. He’s has been working with mosquitoes since he was a little boy. He says watching many of his fathers’ patients die of malaria in his native country led him to his current profession of killing mosquitoes.


“I grew up in Indonesia, and malaria is a big killer of people there. Almost six to ten million people every year get killed by malaria. And there’s probably ten times more mosquitoes there than here.”


Liem uses larvaecide in his district. He hasn’t sprayed since 1977, after the
outbreak of St. Louis encephalitis, another virus carried by mosquitoes. He says
spraying was not effective then, and it still isn’t now, as most mosquitoes hide out in
people’s back yards, in the bushes or under leaves. He says the spray released from
trucks in the street just doesn’t reach them. But many of his citizens demand a
visible fight against the mosquitoes.


“They want to see you working. But if you work and you don’t do anything for them, you’re just fooling them. We have many of them that call us, and say, I want you here, I want you to show me that you’re doing something for my money. And we do that just to appease them.”


If people really want peace of mind, personal protection is what most experts
recommend. They say to wear long sleeves and pants between dusk and dawn
when mosquitoes are out in force. If you’re going outside, use mosquito repellent.
And routinely change standing water on your property, such as kiddie pools and bird
baths, to cut down on available mosquito breeding sites.


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

Too Much of a Good Insect?

It’s no secret that the Great Lakes are cleaner than they were 25 years ago. But some of the wildlife that’s rebounded because of the cleaner water is causing some problems for people who live near the lakes. The Great Lakes Radio Consortium’s Paul Cox explains:

Transcript

It’s no secret that the Great Lakes are cleaner than they were 25
years ago. But some of the wildlife that’s rebounded because of the
cleaner water is causing some problems for people who live near the
lakes. The Great Lakes Radio Consortium’s Paul Cox explains:


(sound of waves and seagulls)


It won’t be long before a sleeping multitude awakes in the Great Lakes.
Millions of mayfly larvae have been burrowed in the muddy bottom of the
lakes. Soon, they will rise, take wing and fly off in search of a mate.


Often, they end up on shore. There they get on everything.


Breck Coombs has seen them invade the car dealership he manages in
Port Clinton, Ohio on Lake Erie.


“I have bugs all over the whole building. It’s almost like you’ve got to
have a second set of clothes when you come into work a lot of times.
You sit down and they make a big mess on your clothing. It’s pretty bad.”


During mayfly season his workers have to wash every car in the lot every
day so the bugs and their droppings don’t mar the paint.


The mayor in Port Clinton is Tom Brown. He says since the mayfly has
been increasing in population the insect has caused some bizarre
events. The way he describes it, it sounds as though it’s like living in an
Alfred Hitchcock thriller. He remembers once getting hit by the bugs
while he was at a drum and bugle corps competition.


“We were watching the show and all of a sudden I looked to the sky
and I saw a black cloud. The mayflies came onto the field, they began to
swarm. I was covered with mayflies from head to toe.”


Aside from the mess they make, the mayflies are – for the most part –
harmless. Fred Snyder is an aquatic biologist with the Ohio State
University Extension Service. He says the mayfly is a bug with no bite.


“Mayflies do not have working mouths. This is a mouthless insect. It has no stinger.”


But Snyder says the mayfly is still something of a nuisance because they
don’t smell very good.


“One evening just coming back into town I noticed a very,
very disagreeable smell. The place stunk. Sort of like dead fish, but
different. But very strong.”


And… the sheer numbers of the mayflies are a problem because the
insects not only fly by the millions, they die by the millions.


Mayor Brown says when that happens… the dead bugs can be a bit of a
hazard.


“When they were heavy we had signs on the streets: ‘Slippery, mayfly hatch.’
And there were a couple of accidents from people sliding around on those mayflies.”


As you might imagine… millions of smelly, messy and dead mayflies are
bad news for any town… but especially so in a tourist town such as Port
Clinton.


But biologist Fred Snyder say the mayflies are also good news. The huge
mayfly population means the lake is environmentally healthier.


“Mayflies have a high need for oxygen. So when you find
good numbers it tells you that the oxygen level in the water is very
good.”


It’s not always been that way. Pollution in the lake took its toll. Oxygen
levels dropped. And the mayflies almost disappeared by the 1950’s.


Dr. Carl Richards, with the Minnesota Sea Grant program, says the
presence of organisms such as the mayfly can be a better indicator of
the lake’s health than testing for polluting chemicals.


“It’s often very expensive and difficult to measure chemicals.
And the ultimate reason we’re interested in chemicals is because of
the organisms. It’s the fish, the birds and the plants we’re concerned
about. So the idea is if the fish and the birds and the plants are
healthy, then the environment must be healthy.”


And a recent federal grant will help scientists look further into the
connection between the health of organisms such as mayflies and the
environmental state of the Great Lakes.


Lake Erie near Port Clinton is not the only example of rebound in the
mayfly population. There’s also been a sharp mayfly population increase
in the waters immediately near Erie, Pennsylvania.


It’s not only good news for the mayflies. It’s good news for fish too.
Some fish feed on the mayfly larvae. So, with more mayflies, there’s
more food for fish.


But, people still have to deal with the annual mayfly onslaught. In
places such as Port Clinton, that means trying to find ways to reduce the
invasion. One thing the city does is turn off streetlights and ask
residents to turn off as many exterior lights as possible in hopes of
attracting fewer bugs during the peak season.


The mayflies that do make it ashore and die are picked up with street
sweepers and composted. In fact, the city got a grant to build the only
licensed landfill in the U.S. for mayflies. There, they compost the
carcasses. Biologist Fred Snyder cooked up the recipe.


“It’s basically sawdust that is mixed about two to one with the
mayflies that are picked up by the street sweepers and brought to
the composting site.”


After several months the mayfly compost is used for gardens and lawns
all over town.


(sound of waves)


Now, Mayor Brown is trying to convince the townspeople to look beyond
the nuisance factor and embrace the mayfly as the standard-bearer for a
cleaner lake.


“We even came up with a theme: Come to Port Clinton where
your dreams may fly.”


It might not offer much comfort to those afflicted by the annual mayfly
invasion… but hey, it’s catchy.


For the Great Lakes Radio Consortium, I’m Paul Cox.

New Method Assails Exotic Hitchhikers

A new way to prevent rust in the ballast of ships might also prevent many alien aquatic animals from being transported from port to port. The Great Lakes Radio Consortium’s Lester Graham has details:

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: