By Sharon Wootton Herald Columnist
The cold of a Northwest winter causes animals to adapt in many ways. Some move vertically, down to lower elevations (elk). Some go horizontally, migrating south (osprey, butterflies, songbirds). Others dig down under (worms), keeping below freezing soil.
Most stay safely out of sight of predators, or of us, for that matter.
“Winter is a lean time for all wildlife,” said biologist Chris Anderson of the Department of Fish and Wildlife’s Mill Creek office.
“It’s the season that naturally helps keep wildlife population levels in check and in balance with available habitat. To survive, animals exhibit different behaviors, strategies and activity patterns, based on their biological needs,” Anderson said.
Biologist Patricia Thompson, also with the Mill Creek office, sees a comparison with humans.
“Like us, with our comforters on the bed, snuggling down during the winter, animals have their little holes at the base of snags or stumps where they make small mammal beds,” Thompson said.
“We can see some small-animal nests, and squirrels in particular with their big bundles of leaves and twigs high up in the trees. They curl up for the winter and pretty much stay there,” Thompson said.
Many frogs, snakes and other amphibians and reptiles do not have a way to stay warm, so they find areas within their preferred habitat to stay out of the “freeze zone.”
These areas include the bottom of a pond that does not freeze totally, below rock piles, in rocky cliffs, and under large trees and snags. They go into a reduced metabolic state known as brumation, the equivalent of mammalian hibernation for cold-blooded reptiles and amphibians.
Lethargy sets in, and some reptiles and amphibians may not move as long as the cold weather lasts.
“We have a tendency to cut down dead trees, but the best way to help wildlife in the winter is to retain natural habitat, their winter homes,” Thompson said.
“Brush piles are really good for little birds and small mammals. Some bats actually squeeze between layers of bark. Birds huddle against the tree trunks, which give them a lot of shelter.
“Evergreens are very important for birds and mammals. Raccoons climb high up in Doug firs. It’s so important to have snags,” Thompson said.
People who feed hummingbirds may see a hummer “frozen” on a perch or deck railing. The hummingbird probably is in a state of torpor, not frozen to death.
Its temperature and metabolism rate have significantly been lowered.
“You need to leave it alone. Torpor is a natural state for it to be in. Torpor is a very significant lowering of body temperature that allows it to survive the cold weather,” she said.
That’s how I feel when I’m wrapped in a comforter — in a natural state that allows me to survive those dark winter days.
On the bookshelf: Finally, a comprehensive guide to stair-walking. Jake and Cathy Jaramillo’s “Seattle Stairway Walks: An Up-and-Down Guide to City Neighborhoods” ($16) is a guide to walks that include 25 staircases and more than 10,000 steps in 25 Seattle neighborhoods.
The slick pages are full of detailed directions, walking times, color photographs, maps, sights to see, history, kid-friendly opportunities, cafes, pubs and gardens.
So while you’re in Seattle for an event, show up a little early and walk the stairs.
Columnist Sharon Wootton can be reached at 360-468-3964 or www.songandword.com.