by Carl Wolf
I see the 2” of snow last week turned out to be about 12.” This morning it was minus 12 at our outpost and both Labs loved it! So, how do animals deal with the extreme cold and deep snow? I notice Prairie and Special stop and lick a paw every so often because ice forms between their toes as snow gets in there and freezes. Just like outdoor critters they can get frostbite or hypothermia. Each dog pauses frequently to eat snow and sometimes I break up frozen snow so they can get at the moisture. Our walks continue twice a day every day and last week we were often quite alone. Tracks indicated fox, coyote, mice, and rabbits are still out there but not as often.
Animals must maintain their internal body temperature in cold conditions. Critters have their own temperature sensing points which can vary from species to species. One example is frogs which can sense being cold at a lower temperature than a mouse. Research has found that hibernating mammals like squirrels do not sense the cold until lower temperatures than those that do not hibernate. How do animals handle cold? Some simply slow down to a state of torpor or decreased activity. While appearing to be asleep some may be hibernating which is a longer period of torpor.
Songbirds, mice and other small wildlife lose heat faster because they have large surface areas to their bodies compared to their size. They use up more energy in contrast to larger animals. Wildlife up here in the frozen north have developed ways to beat the cold. They tend to have larger bodies and turn to herding, denning, burrowing and roosting in cavities. Others build fat reserves, grow thick fur or have insulating layers of air against their skin under the fur or feathers. Hard to understand but very important is countercurrent heat exchange where warm arterial blood flowing away from the heart warms up the cooler venous blood heading toward the heart. Think of it this way, warm blood from the heart (artery) is running alongside cold, returning blood (venous) which helps keep both warm.
I see geese standing out on the ice these days and wonder how they can do that. Again, it is countercurrent heat being exchanged as blood from the heart goes to the toes the warmth spreads to the veins alongside carrying blood from toes back to the heart. The body core stays warm while limiting heat loss when legs are cold but not so cold that tissue is damaged. Fish do something similar as they exchange oxygen with their gills. Fish also can live under ice without freezing because ice floats and water which is denser is down below as a liquid allowing fish to swim while they could not in frozen ice.
A different survival mechanism is brown adipose (under the skin) tissue (brown fat) rich in mitochondria (chemical energy) which can release energy as heat generating warmth without muscle contractions (like shivering). I have developed a lot of brown fat so I can walk my dogs and not freeze. (Jeanette does not buy that argument either). So, next time you see a squirrel running around on top of snow and wonder how they survive remember this – they got ways!
Sorry, very little political crap this time. Finally realized it was a waste of time since most ‘Americans’ have no clue as to how our country runs or why respect and the truth is important. Realized this when I found out the following from recent surveys. Some 7% of adults believe chocolate milk comes from brown cows. Some 1 in 5 adults did not know hamburgers are made from beef. Over 50% of 4,5,6 graders did not know pickles were cucumbers or that onions and lettuce were plants and 3 in10 did not know cheese is made from milk. Some 55% believe Christianity was written into the Constitution and the founding fathers wanted one nation under Jesus including 75% of Republicans and Evangelicals. Only 40% were able to name all three branches of the government – executive, legislative, judicial (not Trump, McConnell and Fox News). Less than 25% knew a Senator’s term is for six years and only 29% knew how many Senators there were. ‘Nuff said?
Oh, and the sketches last week were made by me. The two paragraphs after them somehow got lost but I am including them here because to me they are important. (Floating the Missouri River) We passed over the cable that pulls the flat bottom barge on which cars and trucks ride to get across the river. A donkey engine puffs away as it pulls the cables back and forth. This location is way down the river from Coal Bank. We often stopped, sometimes for hours or days at a time to explore the unique rock formations. Many are long ridges that run down to the river looking like the jagged, backs of dinosaurs. I had a camera but took special pleasure in trying to capture things we saw in sketches. Not very good at it but at least the images were recognizable.
(Re: reader comments) Jose, did you catch Vietnam veteran Nathan Phillips (an elder of the Omaha Tribe) being treated as if America was becoming great again? Right after the March for Life (I know, you pointed out how poorly as a godless Democrat I understand politics) he placed himself in front of white, Catholic kids brought up by their parents to show American greatness. Unfortunate, the student’s sneering slur was misunderstood. Jose, from me, another Vietnam disabled veteran, God help our Democracy because Trump sure as hell isn’t!
Editor’s Note:
Carl, Carl, Carl, I couldn’t help but comment on your article this week as I thought your perspective on animals and keeping warm was timely, in depth, and interesting.
I’m sure glad you kept out all the “political crap” as you stated earlier in our column.
However, I was thinking you accumulated the brown adipose tissue (brown fat) as writing an outdoors column like this would require thick skin.
As you can see, I’ve got you beat in regards to the brown fat (compared to white fat??) as I’ve been getting lots of exercise jumping to conclusions, dodging responsibilities, passing the buck, flying off the handle, and carrying things too far while pushing my luck… all while trying to find a new reporter.
Until then, Keep up the good work!
JDM
