A Memory of Dot from April 2003 - UPDATE November 29, 2023

Dot at den 4-8-2003

Monday, when Donna and I were visiting Colleen’s family in Minneapolis, I got a call that Pondchat moderator Lisa had posted this memory. I immediately knew I wanted to share it in an update. Dot is Shadow’s granddaughter born to Blackheart in January 2000. Little Dot and her littermate Donna each developed a special trust as Doug Hajicek filmed in ‘The Man Who Walks With Bears.’ One of the discoveries Dot made possible was this revelation of how she and her cubs Cinder and Trueheart lost body heat from different parts of their bodies in their den. This memory grew out of a phone call from the BBC as is told below.

Heat Loss in Dens

In 2003, the BBC phoned researchers for help with a documentary using new thermal imaging technology. The telephone conversation sounded something like:

BBC: “We’re looking for someone dumb enough to try putting tiny cameras under a mother black bear with cubs in a den. Do you have such a person?”

Researcher: “Will it have educational value that we can use at the Bear Center someday?

BBC: “Yes. One of the cameras will make the very first thermal images of heat loss patterns in dens.”

Researcher: “We have just the person.”
In the first week of February, the BBC and the researcher went to the den of 3-year-old Dot. The researcher crawled into the den, showed Dot the camera, and gently eased it underneath her, revealing cubs less than 2 weeks old.

The camera was connected by cable to a monitor 30 feet away. A BBC producer watched the monitor and told the researcher where to aim the camera—up, left, hold steady, etc.

In early April, the team filmed the bears again shortly before they emerged. At one point, the researcher momentarily stepped away from the den during a blizzard and returned covered with snow. When he started to enter the den, the mother didn’t recognize him and lunged. The researcher spoke and offered his hand for her to smell. The nervous mother relaxed, lay back down, and even lifted a leg as he put the camera under her again.

Narrated by David Attenborough, the documentary shows heat loss to be especially great from the eyeballs, nose, and forehead. This helps explain why bears tuck those parts under the chest when they curl up on their stomach in the hibernating position. The main area exposed is the thickly furred back.

Thank you Lisa for reminding me of this. It felt good when Dot showed me her trust that led to results that David Attenborough showed the world and we now show in the North American Bear Center.

And thank you all for all you do.
Lynn Rogers, Biologist, Wildlife Research Institute and North American Bear Center

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