The Polar Bears of Pulpit Rock-- Facts or myths you must know before working them!

[Edward R. Breneiser-2]

Here are a few facts about “Polar Bears” you might want to remember!
Please read to the bottom. -- WA3WSJ

In the wild, adult polar bears live an average of 15 to 18 years, though
biologists have tagged a few bears in their early 30s. In zoos, many
captive bears live until their mid- to late 30s. One individual in
London lived to the ripe old age of 41.

As part of a study funded by the Universities Federation for Animal
Welfare, Ames researched the behavior of captive polar bears in British
zoos. She has seen her subjects stack heaps of pipes that they later
knock over in elaborate games. She has also watched them smash open ice
blocks in order to extract imbedded fish.

…Her conclusion: the great white bears are just as smart as apes.

"This is learned behavior and reveals that polar bears are very
intelligent animals," Ames told the London Observer. "They are highly
cognitive creatures that top the food chain in polar regions. You have
to be very clever to do that. Hunting and trapping a seal is no easy
matter."

Because of the polar bear's intelligence, Ames favors a move away from
the concrete cages of the past. "[Polar bears] respond well to
stimulating environments," she says. "They like areas of sand, grass,
and hard ground in their enclosures."

Despite what our eyes tell us, a polar bear's fur is not white. Each
hair shaft is pigment-free and transparent with a hollow core. Polar
bears look white because the hollow core scatters and reflects visible
light, much like ice and snow does.

When photographed with film sensitive to ultraviolet light, polar bears
appear black.

     Early speculation over this discrepancy produced a theory, now
widely repeated as fact, that polar bear hair acts like a fiber optic
guide to conduct ultraviolet light to the skin.
     In 1998, Daniel W. Koon, a physicist at St. Lawrence University in
Canton, New York, decided to actually test whether or not polar bear
hair could efficiently conduct ultraviolet light.
     Koon and a graduate assistant, Reid Hutchins, obtained polar bear
hair from the Seneca Park Zoo in Rochester. Their experiments showed
that a one-fifth inch strand of polar bear hair was able to conduct less
than a thousandth of a percent of the applied ultraviolet light. With
such a high loss rate, meaningful amounts of ultraviolet light cannot be
reaching a polar bear's skin.
     Instead, Koon believes the ultraviolet light is absorbed by the
keratin making up the hair.

A polar bear is so well-insulated that it experiences almost no heat
loss. In addition to its insulating fur, the bear's blubber layer can
measure 4.5 inches thick.

So effective is the polar bear's insulation that adult males quickly
overheat when they run.

Because polar bears give off no detectable heat, they do not show up in
infrared photographs. (Infrared film measures heat.) When a scientist
attempted to photograph a bear with such film, he produced a print with
a single spot--the puff of air caused by the animal's breath.

So don’t try to photograph the “Polar Bears” up on the mountain at
Pulpit Rock tonight without a light source!

Pulpit Rock Polar Bear Facts or Myths:
1. Yes the “Polar Bears” of Pulpit Rock also “respond well to
stimulating environments,”
2. Some of us have a , “blubber layer can measure 4.5 inches thick.”
3. “She has also watched them smash open ice blocks in order to extract
imbedded fish.” The same way the “Polar  
Bears” of Pulpit Rock break open the pileups!
4. “…Her conclusion: the great white bears are just as smart as apes.”
The Polar Bears of Pulpit Rock are also just as smart as apes, but don’t
push it beyond that!

I hope to work many of you tonight from Pulpit Rock on the AT. If you do
work this Polar Bear, just picture me sitting on a small stool in the
snow on top of the mountain on the rock looking out over a moonlight
valley. Does it get any better than this? I think not!
72,
Ed, WA3WSJ



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