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Crookston Times - Crookston, MN
  • Mountain lion study on track in North Dakota

  • Stephanie Tucker, furbearer biologist for the North Dakota Game and Fish Department, said the study, which began in August of 2011, should be wrapped up in the field this fall.
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  • At least 16 mountain lions have been captured and collared in the Badlands in a three-year study of what is likely North Dakota's apex predator.
    That's roughly one-fifth the number of mountain lions that have been legally harvested in the state since a season was established in 2005-06.
    Stephanie Tucker, furbearer biologist for the North Dakota Game and Fish Department, said the study, which began in August of 2011, should be wrapped up in the field this fall.
    The $218,000 study, paid for by Pittman-Robertson excise tax monies, is a collaborative effort between the Game and Fish Department and South Dakota State University.
    Dave Wilckens, a New York native and a graduate student at SDSU, has been on the ground conducting the live trappings in the Badlands since the beginning of the study.
    He said the latest cat was captured at the end of last week. Of the 16 lions that have been collared during the course of the study, Wilckens said 11 are still being tracked, the Bismarck Tribune reported (http://bit.ly/10fyZGQ ).
    He said a couple of animals have been killed during hunting seasons and by vehicles, with a couple killed otherwise.
    Wilckens said he uses road-killed deer to bait foot hold traps or foot snares, usually having one trap active at a time.
    He said the first winter of the study conditions were tough and some traps when undisturbed for months before drawing in a lion.
    Other times, they were effective on the first day.
    Tucker said the goals of the study are to provide the first definitive picture of North Dakota mountain lion population in terms of health, disease prevalence, reproduction rates and survival rates based on age structure.
    Tucker said when the first hunting season was implemented nearly a decade ago, there was little information — either anecdotal or biological — on mountain lions in North Dakota.
    She said having a hunting season is an effective way to gather data. "An animal in hand will tell us a lot about the population."
    Wilckens said when an animal is captured, he gets some help from Game and Fish biologists and in about 45 minutes the animal's vital measurements are recorded, a blood sample drawn and a tooth extracted to determine the age.
    He said the collars have a battery life of about two years and emit GPS (global positioning satellite) coordinates every three hours.
    Once a day, the collar will upload data to a satellite that relays the information to the manufacturer that in turns, emails the information to Wilckens.
    Before the battery gives out completely Wilckens said it has a feature that allows the collar to drop off the animal, but can still be recovered using a lower power VHS signal and hand-held antenna.
    Page 2 of 3 - The collar will give off a warning signal prior to failing and it's hoped the animal can be located and recaptured and fitted with a new collar.
    He said he won't start crunching the data until he returns to SDSU to work on his thesis, which will be completed in June of 2014.
    The data points, or way points transmitted by the collars, will help Wilckens hone in on behaviors like daily movement, range and feeding habits.
    In particular, he said multiple locations in one area may signal the mountain lion is feeding or bedding down.
    It's been an even split between males and females and all of the cats that have been captured are in pretty good condition physically.
    "It's fairly representative as a whole of the demographic that's out there," Wilckens said.
    Tucker said information collected will help the Game and Fish Department manage mountain lion seasons in the future by getting a firmer picture of issues like disease and mortality rates.
    Some of the diseases the cats are monitored for include rabies, plague and parvo virus and so far there have been no issues.
    Wilckens said during the first year and a half, he focused on capturing animals and is now looking at behaviors, habitat use, home range of the animals, daily movements and feeding habits and kill rates of prey.
    A full year's data has been collected on some of the animals' feeding habits, he said.
    Mountain lions have a reputation of preying on large animals like deer and elk and while that is a part of their diet, Wilckens said they fairly versatile in what they will eat.
    He said they are known to also hunt smaller mammals like porcupines, beavers, raccoon and in one case, there is evidence a mountain lion killed a coyote.
    He said it's not clear, however, if they were competing for the same meal.
    Wilckens said some times mountain lions will cache their kills, covering them and coming back later to feed on them and other times they won't.
    Increased oil activity may or may not have an effect on the movement of mountain lions but Wilckens said there is no way to know because studies have not been done until now.
    While some of the research is being done on public land, much of it also is being conducted on private land in the West.
    Wilckens said many landowners have been willing to allow the study to be done on their land knowing that mountain lions are now a part of the landscape and a part of everyday life.
    Others are less tolerant. There was a time when a mountain lion sighting made headlines all across the state.
    Page 3 of 3 - Tucker said that has changed somewhat as people have become more accustomed to knowing the cats are out there.
    "I do think attitudes have changed somewhat and people have adjusted," she said.
    Because of their secretive nature, Tucker said it will be difficult to put a firm number on how many mountain lions are in the state, but it is a species that historically never has been listed as extirpated, or wiped out, from North Dakota.
    Tucker said what is being learned is mountain lions face many of the same challenges as other wildlife in terms of maintaining a healthy population.
    Females do not reach reproductive maturity until they are 3 years old and have a fairly low reproductive rate, giving birth to two or three kittens every 18 months.
    In the wild, a mountain lion that lived until they reached 7 years of age would be considered old, meaning females might give birth to five kittens in their lives.
    "That's one of the things we're trying to find out," she said. "North Dakota is unique in our management of mountain lions compared to surrounding states," she said.
    Tucker said North Dakota's population is relatively small and contained in a relatively small area.
    The first season had a quota a five cats. Two hunting units have been established; one basically covering the Badlands area and the other covering the rest of the state.
    There is no quota in the eastern unit and only a handful of mountain lions have been killed since the season was implemented.
    The harvest quota in zone one (west)was increased to 10 in the 2010-11 season and 14 in the 2011-12 harvest season.
    Tucker said it's recognized that the small population of mountain lions in western North Dakota relies on habitat in the Badlands, Missouri River Breaks, and Killdeer Mountains regions — roughly 6 percent of total state's area.
    Between July 1, 2011, and June 30, 2012, there were 97 reports of mountain lions with 39 (34 percent) verified by carcasses, photographs or other means. The distribution of verified mountain lion reports occurred predominantly in western North Dakota, particularly the northern Badlands region, according to the Game and Fish Department.
    "Generally speaking, we have a small, but healthy population, she said. And while some animals may have wandered into the state from Montana and South Dakota, she said DNA testing has shown the lions here truly are our own.
    "We have a distinct, unique genetic population in North Dakota," Tucker said.
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