Missouri Whitetails - Your Missouri Hunting Resource banner
1 - 20 of 95 Posts

·
Registered
Joined
·
3,269 Posts
Discussion Starter · #1 ·
DNR pilot study seeks to unravel the mystery behind Iowa's declining turkey population

Michaele Niehaus

The Hawk Eye – Published August 1, 2021

DNR pilot study seeks to unravel the mystery behind Iowa's declining turkey population



As pheasants crowed from the timber and the smell of smoke carried to southern Iowa from wildfires raging in the north and west, Brier Klossing listened to the quiet beep of a nearby transmitter.



The beeps, occurring at a rate of about one per second, were coming from a backpack affixed to a turkey hen last winter, indicating she is alive and in motion.



Klossing, a Mount Pleasant native and Iowa State University biology and animal ecology major, is spending her summer as a seasonal technician for the Iowa Department of Natural Resources, tracking and monitoring turkey hens and their offspring, or poults, for a pilot study on downward-trending turkey populations.



"It's not Iowa turkey populations," said Jim Coffey, a forest wildlife research biologist with the Iowa DNR. "It's Midwestern turkey populations. It's nationwide turkey populations, which means: Is there a bigger overall issue that biologists have to be looking at?"

With the telemetry study, Iowa joins Missouri and Illinois in trying to solve the puzzle of what's driving the 30-year trend.



"We've kind of seen this long-term decline in the number of poults being produced every year, so that's our major concern with this project," DNR wildlife research biologist Dan Kaminski said. "If we're seeing four poults for every hen, we're swimming in turkeys the next year. If we get below 2½ poults per hen, we're talking about a population decline problem, and our numbers, and everywhere else in the Midwest, are about two poults per hen."

What's causing the decline in poult production? That's what Kaminski, Coffey, Klossing, and other biologists in Iowa, Missouri and Illinois are trying to determine.



Each of the three states has focused its studies on specific factors, though none are ruling out other causes. Illinois is examining the impact of black flies, while Missouri is looking into the possibility of increased predator-related mortality among turkeys. Iowa is looking at whether disease is to blame.

"With our focus on disease, that's not us saying that we think predation isn't part of the issue," Kaminski said. "Turkeys have evolved with raccoons. They've evolved with bobcats. They've evolved with all of these other critters on the landscape. But beyond that, we've got new things showing up like this LPDV that we don't know exactly what the impact is going to be on wild birds, and that's what we're really trying to answer with our piece of the puzzle."



What is LPDV?

LPDV, or Lymphoproliferative Disease virus, is a Middle Eastern poultry disease that can cause cancer and external issues that can impact eating and vision. It does not infect humans.



The first cases of LPDV in the United States were detected in New York in 2009. The virus since has made its way to the Midwest, and it has been found in turkeys throughout Iowa, Coffey said.



Coffey, with the help of a student at ISU, has been studying LPDV in Iowa for the past couple of years.



"We were actually hoping when we started the study that we would find no LPDV and then we could rule that out as one of the variables," Coffey said. "There's very little known about it because it's been considered a domestic turkey disease, and so there's not much understanding of what it would mean in wild populations."



Coffey said the concern with the LPDV is not cancer, as most turkeys don't live long enough to develop cancer, but other possible impacts, such as whether it can cause decreased egg and poult production by preventing infected hens from doing what they need to keep themselves healthy and whether it makes them more vulnerable to predators.

'The art of the science': How biologists are harnessing technology to study poults

In January and February, DNR biologists convened in areas of southern Iowa featuring a mix of farmland, forest and grassland that, despite being an ideal turkey habitat, has seen a decline in turkey populations.



Using net rocket launchers, they caught nearly 30 turkeys, taking blood samples and oral and cloacal swabs from each. Those samples were used for genetic sequencing for viral, bacterial and fungal markers.

"That will tell us a whole suite of diseases they are either carrying or were exposed to," Kaminski said.



But the study seeks to go beyond disease detection to determine nesting behavior, poult production and poult success rates, as well as mortality, meaning further observation is needed.



Twenty-four hens then were equipped with GPS transmitter backpacks, paid for with grant money from ISU, and released back into the wild.



Satellites pinged the locations of each of those turkeys several times a day, with each turkey's location showing up as a different colored dot on Kaminski's screen.



If a hen has been stagnant for 16 hours, a mortality alert is sent to Kaminski via email.



This does not always mean the hen has died, however. Klossing explained that on rainy days, hens may stay in one spot for an extended period of time to conserve energy. It's up to her to make that call.

"This is the art of the science," Coffey said. "We rely on the technology to reduce our cost, because we can monitor from satellites, but a satellite can't do what Brier can do, which is determine, is that bird actually nesting or is that bird dead? And can I go in and look at it or do I back off a day because it's raining? And I make a determination that that bird's just sitting tight on that nest, because we don't want to spook that bird off that nest."



In early summer, dots of the same color grew closer together, indicating the hen was nesting.



"You'll see this spread of points around the forest or around the landscape and then one day they'll just lock down and you'll start seeing all these points hitting in one spot and you know the bird is starting to incubate," Kaminski said. "So from there, we can kind of look and see 26 to 31 days, this bird's going to hatch its nest, and then one day after 26 to 31 days, you'll see that point move, and that's the indication that we'll want to come in and try to trap the poults."



When the GPS signals indicated the hen moved outside of that cluster within the 26- to 31-day time frame, Klossing would head toward the location of a suspected hatch, navigating the terrain in search of the hen before launching a team to to the nest.



"From there, you try to be as stealthy as possible and bring the team or at least a few people to try to get up to her close enough so that you could ideally flush her away from the poults and the poults would stay there so that we could collect the data and put on the transmitters," Klossing said.

But catching poults can be difficult. They're fast and tend to stick close to their mothers. Ultimately, only two were equipped with transmitters. One came from a brood of four poults while the other was the only one in its nest.



Turkeys lay an average of 11 or 12 eggs per clutch, Coffey explained, but there's no guarantee that all of them will hatch. From there, mortality occurs in about 70% of the brood due to predators and other factors, such as weather and habitat loss.



"These species are highly susceptible to major rainfall," Coffey said. "Actually, in drought years are when we see turkey production go up."



This isn't because turkeys lack the sense to close their beaks when it rains, as one old folk tale suggested. It's because poults put all of their energy into growing. When it rains, the temperature becomes cooler and it requires more energy to stay warm.



"When you're young and growing, you're burning energy to grow, so you've got two rationales on how to use energy and then you don't have a bug population to support that energy growth," Coffey said. "So what does that have to do to your survival? It's probably not good in most cases."

Rethinking poult survival

Klossing continues to keep tabs on the poults as stealthily as possible to avoid being detected and cause the birds stress.



Relying on the mother's signal to provide a location, Klossing is able to get close enough to the poult to further close in on its location using the frequency for its transmitter, which can send a signal as far as 100 yards.

The research is meant to re-examine a long-held belief by biologists that survival rates among poults equal those of adult turkeys once they are four weeks old.



This belief is rooted in several factors, the first being that poults are able to roost at four weeks.



The second is that broods consisting of multiple hens and their offspring begin to form as the poults grow older, meaning there is more protection.



The third has to do with battery life.



"(Kaminski) is really answering a question that we as turkey biologists have been assuming for 40 years and have not had the technology to actually answer," Coffey said.

Batteries and the transmitters they power must be small and light so as not to alter the bird's behavior or hinder its chances for survival. Small batteries, however, mean a shorter battery life.



"That's one of the biggest challenges we have as researchers with this emerging technology," Coffey said. "We don't want the transmitter to impact the true behavior of the animal, so we try to keep the weight ratios down low, and of course that means keeping batteries small, which means you have the trade-off of how big of a battery can you have and the duration of the transmitter, so we're always looking at new technologies."



Testing new technology

Kaminski carried a solar-powered transmitter into an area of thick brush located off of a gravel road.



Scouting out an area where he believed a turkey would want to build a nest, he laid down the transmitter.



Biologists have seen success with the solar transmitter with geese, he explained, and he wants to see whether the same technology could be applied to the turkey study.



Geese, however, spend much time in direct sunlight, while turkeys tend to stay in the trees, especially when nesting.



"I want to know in full canopy, will it get enough sunlight to at least maintain a charge enough to work?" Kaminski said.

If it does work, that technology could last the lifetime of a turkey.



"This solar technology is something we're hoping will give us a longevity that we haven't had in the past," Coffey said. "That's one thing that's Dan and other researchers have been doing really well with is constantly pushing those new technology limits to allow us to gather better data."



Coffey remarked on the benefits of GPS technology.



"While we have done these research projects in the past, we didn't have that GPS technology, so we were making bigger error rates with our habitat estimations," he said. "Now we have precise locations of where turkeys are moving and where they're moving their poults to, so we can look at habitat components on the landscape at a little more of a precise level.



More:How the COVID pandemic and semiconductor shortage have shaped southeast Iowa's automotive market



"That's where people like Brier are going to come in, because they're going to be the young up-comers that are going to get all this new technology that us old people are trying to understand."



Meanwhile, the majority of the transmitter backpacks that were fastened to hens' backs over the winter have gone offline, and Kaminski is eager to try out different transmitters in the coming winter, when he and other biologists plan to expand the study to 40 hens.



Thus far, the only constant has been variability in terms of clutch sizes and hatch rates.



Kaminski, however, has noted some outlying behaviors. While most of the turkeys in the winter flock stuck relatively close to the capture site, one moved seven miles away.

"Another bird moved four miles from the capture site and I think it started nesting, and over the course of two days, that bird was nine miles south," he said. "What I suspect happened was it started to nest, the nest got busted by something."



Kaminski hopes to be able to continue studying the same birds next year.



The study will need to continue for several years to collect reliable data and determine the cause of the trend, and Coffey noted changes to Iowa's landscape and human disruption cannot be discounted.



"Humans have an impact on the landscape in the decisions that we make in how we use that landscape, so turkeys have to adapt to that changing landscape, and we know that Iowa has become a more urban state than it has ever been," Coffey said. "Other places in the United States have changed their landscape, and we might be seeing that impact 30 years later."

Rectangle Slope Font Handwriting Parallel
 
  • Like
Reactions: swampchicken

·
Registered
Joined
·
296 Posts
I have hunted turkeys in Western Iowa and they seem to be plentiful, but some locals say they have actually decreased in numbers. I know some Iowa landowners say they are way down in their county.
 

·
Senior Member
Joined
·
13,987 Posts
"It's Midwestern turkey populations. It's nationwide turkey populations, which means: Is there a bigger overall issue that biologists have to be looking at?"

wonder if other states are looking at this

LPDV, or Lymphoproliferative Disease virus, is a Middle Eastern poultry disease that can cause cancer and external issues that can impact eating and vision. It does not infect humans.

The first cases of LPDV in the United States were detected in New York in 2009. The virus since has made its way to the Midwest, and it has been found in turkeys throughout Iowa, Coffey said.
 

·
Registered
Joined
·
3,487 Posts
I found it interesting that the article states Missouri is looking into increased predator related mortality..
I thought all they cared about was habitat, I guess not.
 

·
Registered
Joined
·
3,487 Posts

·
Registered
Joined
·
7,878 Posts

·
Registered
Joined
·
3,487 Posts
Ol hawk just can't help himself :LOL: :LOL: :LOL:

I wonder when the snippets will start again. :eek:
 

·
Registered
Joined
·
3,487 Posts
  • Like
Reactions: SMPtrucking

·
Registered
Joined
·
3,487 Posts

·
Registered
Joined
·
2,699 Posts
Since 2009, the Great Plains have lost more than 53 million acres of grasslands—an area the size of Kansas—to development.

83% DECLINE in Northern bobwhite quail populations across their entire range (1966-2017)

70% DECLINE in America's pheasant population in the majority of pheasant states since 1970

53% DECLINE in populations of grassland bird species since 1970

Stupid racoons.
 

·
Registered
Joined
·
23,588 Posts
Since 2009, the Great Plains have lost more than 53 million acres of grasslands—an area the size of Kansas—to development.

83% DECLINE in Northern bobwhite quail populations across their entire range (1966-2017)

70% DECLINE in America's pheasant population in the majority of pheasant states since 1970

53% DECLINE in populations of grassland bird species since 1970

Stupid racoons.
And Birds of prey, opossum, skunk, armadillos, Yotes…….
 
1 - 20 of 95 Posts
Top