Page 32 - ARUBA TODAY

A32 FEATURE
Tuesday 21 January 2020
Is winter miserable for wildlife?

By Bridget B. Baker surface area of their body
Associated Press is large compared to their
While the weather outside overall size. To maintain
may indeed get frightful their body temperature
this winter, a parka, knit within normal range, they
hat, wool socks, insulated must expend more energy
boots and maybe a roaring compared to a larger-bod-
fire make things bearable ied animal. This is especially
for people who live in cold true for birds who maintain
climates. But what about higher average body tem-
all the wildlife out there? peratures compared to
Won’t they be freezing? mammals.
Anyone who’s walked their Unfortunately, torpor is not
dog when temperatures a perfect solution to surviv-
are frigid knows that ca- ing frigid conditions since it
nines will shiver and favor a comes with trade-offs, such
cold paw – which partly ex- as a higher risk of becom-
plains the boom in the pet ing another animal’s lunch.
clothing industry. But chip- Adaptations that help
munks and cardinals don’t Unsurprisingly, animals
get fashionable coats or have evolved other adap-
booties. tations for weathering the
In fact, wildlife can suc- Ice crystals cover glass in Detroit, Monday, Jan. 21, 2019. Falling temperatures replaced the week- winter months.
cumb to frostbite and hy- end's falling snow Monday as bitter cold and gusty winds swept across the eastern United States. Wildlife species at northern
pothermia, just like people Associated Press latitudes tend be larger-
and pets. In the northern bodied with smaller ap-
United States, the unfurred compared to a mouse. Re- Many cold-climate endo- species, even below the 32 pendages than their close
tails of opossums are a cent research shows that therms exhibit torpor: a degrees Fahrenheit freez- relatives closer to the trop-
common casualty of cold hibernating mammals, like state of decreased activ- ing point – that is not com- ics. Many animals have
exposure. Every so often an the thirteen-lined ground ity. They look like they are patible with many physi- evolved behaviors to help
unusual cold snap in Flori- squirrel, don’t sense the sleeping. Because animals ologic functions. The result them beat the cold: herd-
da results in iguanasfalling cold until lower tempera- capable of torpor alter- is a lower metabolic rate, ing, denning, burrowing
from trees and manatees tures than endotherms that nate between internally and thus lower energy and and roosting in cavities are
dyingfrom cold stress. don’t hibernate. regulating their body tem- food demand. Hibernation all good defenses. And
Avoiding the cold is impor- So animals know when it’s perature and allowing the is a prolonged version of some animals experience
tant for preserving life or cold, just at varying tem- environment to influence torpor. physiological changes as
limb (or, in the opossum’s peratures. When the mer- it, scientists consider them Torpor has energy conser- winter approaches, build-
case, tail) and the oppor- ing fat reserves, growing
tunity to reproduce. These thicker fur, and trapping
biological imperatives an insulating layer of air
mean that wildlife must be against the skin beneath
able to feel cold, in order the fur or feathers.
to try to avoid the damag- Nature has devised other
ing effects of its extremes. neat tricks to help various
Animal species have their animals deal with condi-
own equivalent to what tions that people, for in-
human beings experience stance, would be unable
as that unpleasant biting to endure. Have you ever
mixed with pins-and-nee- wondered how geese can
dles sensation that urges us appear to stand comfort-
to warm up soon or suffer ably on ice or squirrels in
the consequences. In fact, snow in their bare feet? The
the nervous system mecha- secret is the close proximity
nisms for sensing a range of the arteries and veins in
of temperatures are pretty their extremities that cre-
much the same among all ates a gradient of warm-
vertebrates. One winter ing and cooling. As blood
challenge for warm-blood- from the heart travels to
ed animals, or endotherms, the toes, the warmth from
as they’re scientifically the artery transfers to the
known, is to maintain their vein carrying cold blood
internal body temperature In this June 13, 2017, file photo, the parents of this 7-week old red wolf pup keep an eye on their from the toes back to the
in cold conditions. Interest- offspring at the Museum of Life and Science in Durham, N.C. Associated Press heart. This countercurrent
ingly though, temperature- heat exchange allows the
sensing thresholds can vary core of the body to remain
depending on physiology. cury plummets, are wildlife “heterotherms.” During vation benefits for smaller- warm while limiting heat
For instance, a cold-blood- suffering or just going with harsh conditions, this flex- bodied wildlife in particular loss when the extremities
ed – that is, ectothermic the icy flow? ibility offers the advantage – think bats, songbirds and are cold, but not so cold
– frog will sense cold start- One solution: Slow down of a lower body tempera- rodents. They naturally lose that tissue damage occurs.
ing at a lower temperature and check out ture – remarkably in some heat faster because the q