A Roller Coaster
May 23, 2010 – 9:10 PM CDT
Today was an emotional roller coaster, and it’s not over yet.
At 7:10 AM, Lily gave us optimism when she turned north and moved 1.5 miles to the corner of the lake she’d have to go around to reach the tree where she left Hope. She covered 0.55 miles per hour, swimming a lake and constantly investigating smells. She produced a big green vegetation scat that showed she’s been foraging a lot, but she didn’t forage most of the way back today. She was reading the latest news of who’s been in her territory. When she got to the corner of the lake, she didn’t turn. She kept smelling tracks, branch tips, and trees rubbed by bears. She continued north another mile, checking bear sign.
Sue was heroic in her success in sticking with Lily over a mile—some in the rain—as Lily moved through dense underbrush, blowdowns, and wetlands. A mile doesn’t sound like much until one sees that it’s climbing over, ducking under, and squeezing through while trying not to get poked in the eye or slip on wet logs, rocks, and moss—all the while keeping the bear within sight. Many people who’ve tried this—men and women—have failed. Sue was determined to document what Lily was doing.
Meanwhile, a neighborhood watch was forming for Hope. People will keep an eye out for her, but we are keeping secret the location where they separated so Hope wouldn’t get scared out if she is still there.
We don’t know what to think.
Is this normal? We haven’t had an opportunity to monitor bears in this detail before. We’ve seen cubs separated from their mothers for over a day with no problem. Someone sent an encouraging email about cubs separated from their mother for 4 days with no problem.
Improved technology and methodology is allowing us to witness new things. Separations like this might be normal. But then again, we might be documenting what happens when some cubs disappear. In the past, we’ve documented losses due to predation, falls from trees, miscellaneous accidents, sickness, and starvation. We continue to learn—now with you learning along with us.
Why might a mother abandon a cub? Some have suggested that a mother might give up one cub to mate and produce a litter of three. That doesn’t seem to be the case here. Lily is showing no sign of estrus.
Another possibility is that Lily had to go off and forage because she is lacking a nutrient. She spent this spring in such small areas up until the last couple days that it’s hard to believe she got enough food. While other bears were foraging all over their territories, Lily spent most days in an area 50 to 100 yards in diameter. Did she finally have to get out and forage for her health and the health of her cub, knowing that the cub can survive a few days until she returns ready to make good milk?
Another possibility is that defending her territory is so important to her lifelong reproductive success that she might risk a cub to preserve her territory. When she came down from the red pine, she was very interested in the bear tracks near the base. Immediately after that, she walked away. Eventually she ran, according to the spacing of her GPS points. Was she chasing an intruder? Was she running from an intruder? She then proceeded to check much of her territory. Today, when we expected her to turn the corner of the lake toward the red pine, she instead went straight and checked out fresh bear scat and a big tree that had freshly been used. Such trees are typically used by mothers with cubs. She has to let invading bears know they are unwelcome if she’s to preserve her territory for the sake of this and future cubs.
Lily ended the day with a roller coaster high. About 8 o’clock, as we were writing this, her GPS signals showed her heading for the red pine. We drove to the vicinity, and she beat us there. We got a glimpse of her searching alone. Is it a coincidence that her mother June left her first litter, Pete and George, in that same location when June made a 4-hour foray up to two and a half miles away, presumably to mark her territory while mostly tied down with cubs.
It seems impossible that Lily could be gone for over 49 hours and still find Hope, but bears continue to amaze us. We’ll see what tomorrow brings.
In other news, the male that was wary of June while following her is out of the picture. June is back with old Harry again. Braveheart is alone. Cal is exploring his distant area as if he will stay awhile. This might be his future mating range. This bear that grew up trusting people and that allows us to radio-collar him without tranquilizers is avoiding houses and sticking to some of the wildest habitat in northeastern Minnesota. Many people would not have expected that. The data keep coming in. Let’s cross our fingers for Hope.
Thank you for your contributions.
—Lynn Rogers, Biologist, North American Bear Center