| Written By - WDNR - 06/10/2008 | |
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Link to Original Article here |
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MADISON - Preliminary results of a two-year cooperative study of Wisconsinrnblack bears suggest that the population may be two times or more largerrnthan currently thought. Biologists stress that the new estimate comesrnfrom a half finished study and may change when data from the secondrnyear of the study are analyzed. Early results are encouraging, however,rnand indicate Wisconsin continues to provide quality habitat for largernmammals like bears.
"This is good news," said Keith Warnke,rnDepartment of Natural Resources deer and bear ecologist. "It means wernhave a healthy bear population, and we may be able to expand bearrnhunting opportunity. The other good news is that more people will havernopportunities to see these great animals in the wild."
Therntwo-year, DNR-funded study was conducted by University ofrnWisconsin-Madison Wildlife Ecology graduate student Dave MacFarlandrnunder the guidance of Dr. Timothy Van Deelen.
"The preliminaryrnresults are comparable to bear densities in Minnesota and Michigan'srnUpper Peninsula," said Van Deelen. "Dave and I spent a good deal ofrntime rechecking our calculations and we're eager to see if the resultsrnhold when the second year of data are incorporated."
In the bearrnstudy, some 3,500 baits marked with tetracycline were set out acrossrnthe states bear range in 2006. Tetracycline, when ingested, isrnharmless to bears but leaves a telltale line in a bears bones.rnSuccessful bear hunters in 2006 and 2007 were asked to provide arnsection of a rib bone from bears they harvested for analysis. Fromrnthose samples, the biologists were able to use a formula to calculaternthe estimated bear population.
Using tetracycline is a variationrnon a wildlife population estimating technique known as mark andrnrecapture. Other examples of mark and recapture are banding ofrnwaterfowl and songbirds and radio collars or radio implants on otherrnspecies. When hunters report harvesting a banded game bird orrnbiologists recapture a banded songbird, that information is used in arnmodel to estimate total populations.
Currently, biologists trackrnblack bear populations by placing a series of baits on routes in eachrncounty throughout the black bears range and record which are consumedrnby bears over a week long observation period. Biologists use thesernobservations to help build a population model that also takes intornaccount hunter harvest, hunter success rates, bear population data andrnhistorical harvest rates to generate a population estimate. This modelrnestimates the current black bear population in Wisconsin to be at aboutrn13,000.
It is important to keep in mind that these models bothrnprovide information for us to consider when managing the bearrnpopulation, and both are important to scientific bear management,rnWarnke said. We are always working to improve the science we have tornmanage wildlife populations. The department funded the research tornimprove our bear population estimate and expand the science base wernhave on this species. The Wisconsin Bear Hunters Association was a keyrncollaborator on this study and many members participated in gatheringrndata and contributing research supplies. Id also like to thank DavernMacFarland for organizing and conducting this research and his help inrnenlisting cooperation from the bear hunters.
In therntetracycline study, a much larger number of bait stations were used andrnthe bait stations were constructed in a way that only bears could reachrnthe bait. The new study also carefully adjusted the amount of bait sornthat a single bear would likely consume all of it in one visit, greatlyrnreducing the possibility that one bait might mark two bears. Byrncomparing the number of baits consumed in a season to the number ofrnharvested bears showing the tetracycline marker in their bones,rnscientists were able to calculate the new population estimate.
Officialsrnstress that these are preliminary findings and it is too early to drawrnconclusions or implement changes. The earliest possible changes thatrnwould impact bear hunting permit availability would be for the 2009rnhunting season. Adjusting black bear population goals will necessitaternchanges to administrative rules and involve public meetings, andrnNatural Resources Board and legislative approval.
When thernfinal results are in well be able to use this information to assessrnbear population goals and adapt our bear management program, saysrnWarnke. Any changes to bear management policies will be donerncarefully, with public input and only after thorough analysis ofrnpotential impacts. The first priority is and always will bernconservation of the resource.
Our bear population is expandingrnand one benefit of that is that people can expect to see bears in areasrnoutside what is thought of as traditional range, Warnke said. Despiternbears general shyness toward humans, people in the central andrnsouthwest areas of the state likely can expect to see more evidence ofrnbears as they disperse, looking for new territories.
Adultrnblack bears typically weigh 250 to 500 pounds for males (boars) and 200rnto 450 pounds for females (sows). Infant bears, called cubs, are bornrnquite tiny but by the time they are 2 months old, they weigh about 6rnpounds. Females give birth to two or three cubs in January or Februaryrnwhen they are still in their winter sleep. When standing on all fourrnpaws, adult bears measure 2 to 3 feet tall at their shoulders.
Tips for living safely with black bears
Biologists offer the following advice for avoiding unwanted encounters with black bears:
* Never feed bears " the bear will not forget the feeding experience and will return, possibly becoming a nuisance.
rn * Make bird feeders inaccessible to bears by hanging them at least 10rnfeet off the ground and 5 feet away from tree trunks or on a limb thatrnwill not support a bear.
* Bring feeders in around mid-April when bears emerge hungry from their winter dens.
* Keep garbage cans indoors if possible.
* Bring in pet food at night.
* Do not keep food in your tent if you are camping.
* Store camp food and cooking utensils away from your campsite.
* Dispose of food scraps in closed containers away from the campsite " not in the fire.
If you encounter a black bear:
* Make noise " let the bear know you are there so you dont surprise it.
rn * If you happen to surprise a black bear at close range, back awayrnslowly or, if available, get into a vehicle or structure until the bearrnleaves the area.
* Leash your dogs in known bear country.
* Respect black bears as wild animals and enjoy them safely - from a distance.
Nuisance black bears
Thernagency responsible for nuisance black bears in Wisconsin is the U.SrnDepartment of Agriculture " Wildlife Services. Report nuisance bears tornthem at:
USDA-WS, Waupun district
1201 Storbeck Dr.
Waupun, WI 53963
1-800-433-0663*
920-324-4514
or
USDA-WS, Rhinelander district
PO Box 1064
Rhinelander, WI 54501
1-800-228-1368*
715-369-5221
More information on black bears in Wisconsin is available on the Wildlife Management pages of the DNR Web site.
http://dnr.wi.gov/org/land/wildlife/PUBL/wlnotebook/bear.htm
FOR MORE INFORMATION CONTACT: Keith Warnke, DNR - (608)
264-6023 or Timothy Van Deelen, UW, - (608) 265-3280
Uplodaded by WisconsinOutdoor.com
