Habituation, weight-loss, protection for radio-collared bears

Habituation, weight-loss, protection for radio-collared bears

February 22, 2010 - 9:07 PM CST

Happy 1-month Birthday, Cubbie!  It’s been an amazing trip for us all.  So much has happened since we installed the den cam on January 8 that it seems long ago.

A den cam has been a dream for many years.  Our first opportunity was in 1999 with 3-year-old Whiteheart.   Like Lily, Whiteheart denned close enough to a house to have electricity and telephone.  Doug Hajicek of Whitewolf Entertainment put a technicial team together, and we learned a lot about how bears behave in dens.  That den cam sent video as far as the house, but only stills went out over the Internet—Discovery.com hosted the images.  We waited 10 years for the opportunity Lily has given us.  Technology has improved, and we’re hoping to have a den cam each winter.

The key to a den cam is a trusting bear that will let us set up a camera without running away.  Lily knows our voices and was calm, although she initially was nervous about the big eye of the camera looking at her.  More so, she was nervous about the two cameramen behind us.  Looking at them, she exited the den and we feared she might leave the area.  The cameramen backed off.  We talked to Lily, and she turned back.  With the camera in place, we all left.  She returned within minutes.  We watched our computer screen with relief when she appeared in the camera and her fur streamed by the lens as she crawled back into the den.

When Lynn returned to adjust the camera a few days later, Lily came out briefly but showed no inclination to leave.

Lily trusts researchers who behave in familiar ways, but is wary in other situations.  For example, last fall we homed in on her radio signal without announcing ourselves and heard the signal fade as she left the area.  We followed her signal, announced ourselves, and had no problem changing her collar and taking her heart rate.  We didn’t know her exact weight but knew she was well over 200 pounds and had a good chance of giving birth.  Then, some people disturbed her, probably without knowing Lily was even anywhere around.  Lily moved a couple miles away and attempted to make 3 dens—all in rocky soil.  Fortunately she eventually gave up and came back to this den.

We wondered if she still had enough weight to have cubs and were relieved and ecstatic when she did!

We learned so much about her den preparation before giving birth, her surprisingly long labor, and the sounds she and the cub made immediately after birth.  The care she has given the cub has been as expected from our brief observation of other trusting mothers.  But mother and cub making the contented motor-like humming together last night was a first for us.  There’s always more to learn.

Lily is losing weight twice as fast during lactation as she did earlier in the winter.  We expect she will lose over 40 percent by the time she leaves the den.  Unfortunately, without knowing her weight going in, we won’t know for sure.  Some folks have expressed concern over her weight loss.  Please be assured it’s entirely normal—just part of being a bear.  Bears normally gain and lose large amounts of weight each year.

The value of these trusting bears to science and education is immeasurable.  Years ago, we never would have thought it possible to accompany wild bears and be essentially ignored.  Now we are surprised if the bear we’re accompanying even looks at us.  We’ve become unimportant.  We are not food-givers, but not competitors.  We are not objects of their affection but not enemies.  Once they decided that a familiar observer made no difference to them, they went about their lives foraging, raising cubs, taking naps, mating, etc.  Now, many of the big males in the population are also familiar with us and ignore us as they go about courting and mating.  They have full, wild lives, and once they accept us, it is hard to keep a bear from being a bear.  They‘ve taught all of us so much.  I wish all of you could see what we see and come with us with the bears.  At least we have videos—50 video exhibits at the North American Bear Center with snippets on bear.org.

At first, we worried about the bears becoming nuisances.  We worried they might approach someone else.  We learned that habituation is specific to locations, situations, and individuals.  In time, it’s possible to broaden the habituation.  We had over 200 volunteers walk with one bear.  Yet, even she didn’t approach people.

These bears teach us so much that can help all bears forever, and we have worried that they might get shot.  Each year, we do everything we can to protect them.  For whatever reason, the research bears show much higher survival through hunting season than other bears.   For years, we’ve asked that radio-collared bears be protected from hunting.  This year, with the popularity of Lily, legislators are drafting a bill to do just that.  We are hopeful it will pass.  These bears can teach us so much.  We want to follow Lily and her clan for years to come.

—Lynn Rogers and Sue Mansfield, Biologists, North American Bear Center