Lily has a den!
September 24, 2010 – 3:49 PM CDT
Lily has a den, and she dug it herself. It’s big enough for Hope too. The picture tells the story. In the foreground, rocks and big chunks of wood, soaked by the rain, show how hard she worked. The size of the den shows how hard she worked. It’s no wonder we found them resting in an alder thicket. It’s too early to know for sure that Lily and Hope will use this den, but it looks promising. The den is fairly accessible, although probably not close enough to electricity and telephone to make it as convenient as last year. Whatever the effort and expense required, we must get a den cam into their den to document the unprecedented observations we will likely make this winter. Why do people as old as we are keep doing research? This is one of the reasons.
Lily’s heart rate was only 66, but the untouchable one’s heart rate remains a mystery. Little Hope did let us briefly check her collar, and there’s still room to grow. We put it on so loose, we wondered if it would stay on. It turned out to be just right.
The color of the dirt in Lily’s fur yesterday gave us a clue where to look for the den, and finally, there it was maybe 150 yards from where Lily and Hope were resting. Once we got in the vicinity, all the new dirt covering a 10 by 12-foot area in front of it stood out. Lily’s next step should be to rake bedding into it. Hope might help her with that, and we hope to get video. That will actually be an emotional moment to see them making a den together after all their ups and downs. Sue has to capture it on video to show Lynn because he’s going off to his daughter’s wedding in Louisville, Colorado, through September 29. So much is happening every day.
On protection for radio-collared bears, things are happening behind the scenes now. The two main things we want are (1) Protection for radio-collared bears wearing bright ribbons in the study area in central St. Louis County. If the DNR wants to protect radio-collared bears statewide, that is fine, too. (2) Accomplish protection in a way that will achieve unity on this issue between hunters and non-hunters and between us and the DNR.
Both hunters and non-hunters are calling for protection, and we want to work with the DNR as a partner. We have always wanted that. We have seen mis-statements in the media by some of the people involved, and we aren’t responding. Truth and right will win in the end, and there is a lot of time between now and the next hunting season.
On the other hand, we have seen such wonderful, thoughtful statements and analyses by some of you that we are extremely happy to part of this growing force for bears. The talent and heart that drives Lily fans is leading to something big. And the group will grow.
We were asked about the radio-collars. As part of our kinder and gentler research, we made several changes in the collars over the years. To make them more comfortable, we made them narrower and beveled the edges. We have examined some of the big GPS collars available and do not use them. We also add a piece of material that rots over time and allows the collars to fall off if we don’t replace the material from time to time. As you know, all of this is made easier on the bears by using trust and treats instead of traps and tranquilizers. In many studies, radio-collared bears go 6-12 months between checks for tightness. Adjusting the collars would require capture and sedation—often with darts. In this project, we check the collars on every visit and easily adjust them by giving the bear a handful of nuts.
Two reasons we seldom put radio-collars on males is that (1) many mature males have necks bigger than their heads, and we’d have to put the collars on more tightly than we are willing to do, and (2) young males of dispersal age might travel so far we’d have to use our entire budget for airplane rental to find them.
So the male side of black bear life still holds a lot of mysteries. Most leave the study area as yearlings, but some remain until they are 2 or 3. So, if we see yearlings still here in late summer, we give them radio-collars to learn where they den in relation to their mothers and sisters. As soon as they den up, we go remove their radio-collars.
That’s what we did with Cal. He nicely came to the den entrance and let us remove his radio-collar as a yearling. The next spring, he apparently left the area as we expected a 2-year-old would do. Surprisingly, he reappeared in August. Maybe he had settled nearby. By that time, we had new GPS technology that would reveal which direction he travels from the study area. Knowing the direction greatly reduces the cost of flying to find him at his den. He went 30-36 miles northeast into Canada where flight restrictions would make further study difficult. We found his den for under $1,000 and removed his radio-collar. We thought that was the last we’d see him. We said our goodbyes and thanked him for revealing a bit more about black bear life.
We didn’t realize the story was just beginning. The following spring—this spring (May 8, 2010), he reappeared in the study area. Could it be he didn’t settle in Canada? We gave him a new radio-collar. We watched his GPS signals on the computer as he traveled some 40 miles south! He hadn’t settled in Canada. On May 17, we visited him in his new digs to the south, checked his collar, and changed his GPS batteries. When those batteries expired at the end of May, our attempts to hook up with him failed. On August 25, we flew to home in on his telemetry signal. He had moved only another 18 miles, and we considered removing his radio-collar when we planned to visit him at this den in October. Nine days later (September 3, 2010), he was killed 37 miles farther southwest. He was within 20 miles of McGregor, MN. He wasn’t done yet. We would have loved to radio-track him another year. Where would he finally settle? Would he return to the study area from 83 miles away? Would he visit the area where he’d denned in Canada 130 miles northeast?
As it was, he provided the most detailed information on the travels of a juvenile male we have ever obtained. The data makes us wonder how far other males might travel between visits to the study area. Some of those visits are years apart. For males young enough to have skinny necks, there is a story to be told using the new GPS technology. If the DNR would protect radio-collared bears statewide—not just in our small study area—that would help protect these males as well as the females in the small study area.
Thank you for all you are doing on so many fronts.
—Lynn Rogers and Sue Mansfield, Biologists, Wildlife Research Institute and North American Bear Center