Tag: mallards

Duck Decline Blamed on Fragmented Habitat

  • A mallard duck hen sitting on her eggs in a strip mall tree planter in Ann Arbor, Michigan. Ducks Unlimited researchers have found that recent declines in duck populations are partly due to a lack of corridors between grasslands where ducks nest and wetlands where they thrive. (Photo by Rebecca Williams)

Researchers with the hunters’ conservation group Ducks Unlimited are reporting they’ve found some of the reasons the duck reproduction rate is falling in the Great Lakes region. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

Researchers with the hunters’ conservation group Ducks Unlimited are reporting they’ve
found some of the reasons the duck reproduction rate is falling. The Great Lakes Radio
Consortium’s Lester Graham reports:


(sound of birds, a duck quacking and a truck door slamming)


YERKES: “Load in.”


Two years ago, we went out in the field with biologist Tina Yerkes and other Ducks
Unlimited researchers.


YERKES: “Every day these guys go out and they track the birds and that’s basically how
we figure out what they’re doing. ”


(sound of newly hatched ducklings peeping with hen hissing)


At the time, they were tracking mallard hens, watching them nest, and watching them as
they moved their ducklings from the nests in the grass to nearby wetlands and lakes.
After three years of study, they found some of the reasons duck reproduction rates are
down. We recently had a chance to sit down and talk with Tina Yerkes about the study.
She says, surprisingly, they found that egg production and nesting are good, despite nests
being destroyed by mowers and predators eating the eggs.


TY: “The problem is duckling survival. We have very poor duckling survival in this
area. And, that leads us to believe that we need to alter habitat programs to actually start
doing more wetlands work.”


LG: “So, what’s happening is the ducks are able to nest, they’re able to hatch out the
ducklings, but then when they move from the grasslands where the nesting is to the
wetlands where the ducks feed, they grow, they’re not surviving. What’s killing them?”


TY: “What we’re seeing is that hens, once they hatch their young, they move right after
the first day into the first wetland and it’s a dangerous journey. Basically, because our
habitat is so fragmented that they’re moving these ducklings through non-grassed areas,
across parking lots, roads. It’s dangerous. And, a lot of the ducklings either die from
exhaustion or predators kill them on the way. A lot of avian predators get them at that
point.”


LG: “So, we’re talking about hawks and not so much domestic animals like cats and
dogs.”


TY: “Ah, cats are a problem, yeah. It’s hard to document exactly what is getting them,
but feral cats and domestic cats are a problem. Hawks and jays, sometimes…”


LG: “Blue jays?”


TY: “Blue jays can be mean, yeah. But, it’s interesting to note that if you put those
corridors back between nesting sites and wetlands, it’ll be a much safer journey for
them.”


LG: “So, what are you proposing?”


TY: “I would look more away from urban areas where those infrastructures are already
intact. We would not certainly expect anybody to tear that type of stuff up. But, outside
the cities and urban areas there are lots of opportunities to look at areas where there is
grass existing or wetlands existing and then piece the habitat back together where we
can.”


LG: “There are places, for instance in Chicago, where they’re working to do exactly that.
Do you see that kind of effort in most of the states you studied?”


TY: “Yes, actually we do. Some states like – Chicago’s a very good example. A very
strong park system not only throughout the city, but out in the suburbs as well and we do
see that in a lot of different places. That’s a positive thing.”


LG: “Where are the worst places for duckling survival?”


TY: “The worst duckling survival was the site that you were at two years ago in Port
Clinton, Ohio. And, if you think about what that habitat looks like, what you have is a
few patches of grass and an area that’s heavily agriculturally based, but all the wetlands
have been ditched and drained so that when a bird has to move from an area where it
nested to get to a nice, safe wetland habitat, they have to make a substantial move across
a lot of open fields that don’t have a lot of cover on them. So, here you’re looking at
maybe piecing cover back between the wetland areas and still being able to maintain farm
operations at the same time.”


LG: “What can farmers do to help duck survival?”


TY: “Oh, let’s see. Leave some patches of grass along the fields, especially if they have
wetlands in their fields. Leave a nice margin around the wetland, a nice vegetative
margin around the wetland because the ducks will nest right in that edge as well. Then
they don’t have to move very far to take the ducklings to a nice food source and a nice
wetland.”


LG: “Now, this is not just about making sure that mallard ducks reproduce. What’s this
going to mean for the ecosystem as a whole?”


TY: “Every time we replace a wetland or replace grass on the landscape, we’re
improving the water quality because those types of habitats remove nutrients and
sedimentation from runoff. So, there’s all kinds of benefits. There are benefits to any
other species that depends on grasslands to nest in or wetlands to either nest in or even
for migratory birds. So there’s just a suite of benefits beyond ducks.”


Tina Yerkes is a biologist with Ducks Unlimited. She says the group will be working
with states to develop programs to encourage development of corridors between the
grasslands where the ducks nest and the wetlands where they thrive.


For the Great Lakes Radio Consortium, I’m Lester Graham.

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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.

Related Links

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.