CONSTRUCTING NATURAL HABITATS (Part 2)

  • This grizzly at the St Louis Zoo is displayed in an exhibit that mimics its natural habitat. A whole industry has emerged to manufacture these exhibits.

At your local zoo – if you can suspend disbelief for a moment – you might find yourself in the middle of a tropical rainforest. Or a dusty African plain, watching the animals in their natural habitat. Of course, those wild settings are merely a façade. Clever construction techniques covering up concrete cages. In the second of a two-part series, the Great Lakes Radio Consortium’s Lester Graham reports… the thought and planning behind the displays can be nearly as intricate as nature itself:

Mallard Ducks on the Decline

  • In a narrow swath of grass in a roadside ditch, a mallard hen nests her second brood of the season, a rare event for these ducks. Her first ducklings were killed by a predator.

In the last decade or so, ducks in the Great Lakes region have not been reproducing as well as they have in the past. The number of ducklings hatching out and surviving to adults has dropped by about 25 percent. Researchers are trying to figure out why this is happening and what can be done about it. The Great Lakes Radio Consortium’s Lester Graham went into the field with researchers and has this report:

Transcript

In the last decade of so, ducks in the Great Lakes region have not been reproducing as well as they have in the past. The number of ducklings hatching out and surviving to adults has dropped by about twenty-five percent. Researchers are trying to figure out why this is happening, and what can be done about it. The Great Lakes Radio Consortium’s Lester Graham went into the field with researchers and has this report.


(sound of quack, quack overhead / cross fade to truck doors and engine startup/ bed of gravel sounds)


Mallard ducks are the most common duck found throughout the Great Lakes states. You’ll see them on farm ponds, college lagoons, and even in big city parks. But recently the mallard’s population hasn’t been growing as fast. The duck’s rate of reproduction has been falling off in the region since the mid-1980’s. Researchers with the sportsman’s conservation group, Ducks Unlimited, are involved in a three year study of mallards to find out why the ducks are not surviving in as great of numbers.


Tina Yerkes heads up the project. In a truck with something that looks like a TV antenna on top, fellow researcher John Simpson and she are in northwest Ohio, near Lake Erie, headed out to find some of the mallard hens. Tiny transmitters were surgically implanted in the ducks earlier this year and the antenna tracks the signals.


“So, this is the whole gizmo setup here. Everyday these guys go out and they track the birds. Each bird has a unique beep, if you will, uhm, a frequency. And that’s basically how we figure out what they’re doing. We started with 57 and you’re down to 38?
JS: Thirty-eight, roughly. And, eleven? JS: Twelve. Twelve have actually been killed, either by predators or farming operations on this site.”


(Truck sound under)


As the truck gets close to the last sighting of one of the mallard hens they’re tracking. John Simpson flips on the tracker and turns the antenna.


(beep beep sound)


He’s pulled over along a fairly busy road, and starts looking around in the roadside grass.


“So, she’s actually nesting in the ditch?”
“Yeah. I’m not entirely sure where her nest is here, so we’ve got to be careful.”


(sound of grass rustling)


It’s hard to believe a duck could find a place for a nest here. Most of the roadside is mowed except for a little strip of grass where we’re looking. She’s one lucky duck. A mower would kill her and destroy her nest.


“There she is right there. See her sitting on her nest?”


The mallard hen is three feet away and she’s still hard to see. John
Simpson has to flush her so that he can take a look at the eggs in the nest.


(Sound of flapping wings)


“There she goes.”
“She’s got a pile of eggs too. That’s her second nest.”
“That’s her second nest?”
“Yeah. She had a pile in her first nest.”
“Twelve eggs? Is that right?”
“Eleven.”
“Eleven?”
“Yep.”


(Ambience remains under)


The duck lost her first brood to a predator. Since she had nested close to a subdivision, it could have been a dog or cat. But the researchers say in this case it was probably a wild predator, maybe a raccoon.


“And, once we’re finished, we’ll just cover the nest so the predators don’t see it and we leave.”


It’s very rare that a mallard hen tries twice to raise a brood, But in this area the ducks are adopting a lot of unusual behaviors. Since there’s almost no grassland to nest in, hens have nested in hay fields where they’re usually killed at mowing time. One hen made a nest in a large flowerpot. At our next stop we found a duck in the backyard of a mobile home, and her eggs had just hatched.


(Peep, peep, peep of the ducklings)


The owner mowed around the duck’s nest, giving the mother and her eggs a chance to survive. Now that they’ve hatched, they’ll head to the water nearby. Tina Yerkes says development pressures have hurt the ducks here.


“In Ohio, we’re looking at pretty bad brood survival which tells us that probably we need to alter the landscape by putting wetlands back—by restoring wetlands and managed marshes for the broods. And then, probably also coupling that with some grassland habitat, ’cause as you can see, there’s not a lot of grassland habitat for them to nest in here. We need to improve that.”


The Ducks Unlimited researchers are getting some indications about what kinds of things are hurting the ducks ability to reproduce. Besides the loss of wetlands the researchers are finding that farming practices such as frequently mowing ditches and urban sprawl taking up grasslands are all contributing to a high mortality rate among ducklings and sitting hens. But the researchers haven’t collected enough information yet to make any solid conclusions. It’ll be two more years and many more sites before the Ducks Unlimited researchers have enough hard data.


Robert Payne is the Curator of Birds at the University of Michigan Museum of Zoology. He says while to researchers it might seem pretty clear that people are causing the lower rates of production in the duck population. Information like the Ducks Unlimited group is gathering will be helpful.


“Well, it seems to be common sense: the more people, the more development you have, the fewer places there are going to be for birds. But the people in our society who make the decisions like to have some data out there. (They) Like to know how many ducks, how much land, and so on. Otherwise, these people can’t really figure how much land the really should set aside for the ducks. No data, no well informed decisions.”


(sounds of birds and bullfrogs)


But some people might find data that are supposed to help ducks gathered by a group that’s chiefly supported by people who kill ducks for sport might be a bit of a conflict, or at least very self-serving. Ducks Unlimited researcher Tina Yerkes says there’s a larger purpose here than merely making hunters happy.


“The purpose is not necessarily to create more ducks to shoot, but the purpose is to alter and affect the landscape in a positive way for all the species that need the landscape. So, we’re trying to take a step back and determine what the wildlife needs and help put it back on the ground for the wildlife.”


Predictions are that the human population around the Great Lakes will steadily increase for the foreseeable future, and if the researchers’ early indications hold, it’ll likely affect the duck population even more. This study, when it’s complete, might give policy makers the information they need to find a balance between the needs of people and the needs of wildlife as the conflict between the two grows in the Great Lakes region.


For the Great Lakes Radio Consortium, this is Lester Graham.

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MALLARD DUCKS ON THE DECLINE (Short Version)

Mallards are the most common duck in the Great Lakes region, but their numbers have been declining during the last few years. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

Mallards are the most common duck in the Great Lakes region, but their numbers have been declining during the last few years. The Great Lakes Radio Consortium’s
Lester Graham reports.


The sportsmen’s conservation group, Ducks Unlimited is involved in a three year study, trying to learn why mallard duck populations are not increasing in the same numbers they once were. Tina Yerkes is a research biologist with the organization. She says starting in the mid-1950’s mallard flocks were growing at a pretty rapid rate.


“In the Great Lakes area, after the mid-80’s until now the production ratio has dropped and it’s dropped pretty sharply. And that for us is a warning bell, if you will, that something is going on in this area that’s causing birds not to do well.”


Yerkes and a team of biologists in Michigan, Wisconsin, and Ohio are tracking mallard hens and their broods. Early indications are that loss of habitat is beginning to affect the duck populations in the region. For the Great Lakes Radio Consortium, this is Lester Graham.

New Vaccine for West Nile Virus?

Researchers might soon have a vaccine to protect birds from the West Nile virus. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

Researchers might soon have a vaccine to protect birds from the West Nile virus. The Great Lakes Radio Consortium’s Lester Graham reports.


The centers for disease control and the U.S. Army are getting help to develop a vaccine for prevention of the mosquito borne West Nile virus. Here in the U.S. in the past couple of years, the virus has been responsible for the deaths of thousands of birds from more than seventy species. Michael Hutchins is with the American Zoo and Aquarium Association. He says research into a vaccine ahs been driven by the need to protect birds in zoos.


“The current studies are to develop an injectable vaccine, but the intention is to try to take that and develop an ingestible variety that could be spread on bird feed and would therefore have a hopefully-big impact on wild birds as well.”


Chicago’s Brookfield Zoo, the Walt Disney Foundation, the Wildlife Conservation Society and the American Bird Conservancy have all contributed to the project. Hutchins says a vaccine could be developed as soon as the next month or so. For the Great Lakes Radio Consortium, this is Lester Graham.

Midwestern Refuge Aids Wolf Reintroduction


A Midwestern sanctuary for wolves is helping re-introduce the
Mexican Grey Wolf. The Great Lakes Radio Consortium’s Lester Graham
reports… worldwide the animal’s numbers had dwindled down to five:

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