By Ranger Steve Mueller
Amazing methods for surviving cold weather abound in nature. Cedar Springs became famous by spreading warm red flannels around the world. Humans are not endowed with adaptations for cold climates. Fortunately we have devised many ways to create a tropical climate around our bodies. Homes are heated to tropical temperatures. We clothe to hold heat between clothing and skin so a tropical environment exist in that narrow space even when we venture into freezing outdoor temperatures.
Mammals are changing summer coats to winter coats. Their underfur thickens in fall but it is not waterproof. Outer guard hairs have oils that repel water. The number of hairs in underfur increases producing dead air space to hold warm air near the body. Opossums do not produce a thick under underfur and they become vulnerable to killing cold. There tails are especially are at risk for frostbite.
Birds produce insulating down feathers for winter and those are protected from getting wet by contour feathers that we see covering the body. At the base of the bird’s tail is an uropygial or preening gland that produces an oily substance the bird retrieves with its bill to spread on contour feathers. This water repellant keeps feathers dry in wet weather. Ducks as well as songbirds use the oil to prevent down feathers from becoming waterlogged and losing the ability to provide warm dead air space.
Insects have a variety of adaptations to maintain populations until summer. Most wasps freeze to death after the first few hard frosts but the queen leaves the nest and finds a log to crawl under or some other protected place. There she survives the winter to begin a new colony in the spring.
Viceroy butterflies lay eggs that hatch in late summer and the tiny caterpillars use silk to attach a willow leaf to a branch. The caterpillar hibernates hidden and suspended in the curled leaf until spring. Woolly Bear Caterpillars are seen walking about on warm fall days. They hibernate in secluded locations like leaf litter until spring conditions warm to encourage plant growth. The caterpillar in spring continues feeding and development. A white winged Woolly Bear moth will emerge from the pupa in summer to begin the cycle anew. Many aquatic insects, like dragonflies, winter as larvae in streams with the some adult dragonflies, like darners, migrating south.
June beetle grubs burrow into ground to get below frost line. In 1985 our dog, Ody Brook, died and we buried him in January. Yes, Ody Brook Nature Sanctuary is named after him in 1979. A fire was built with a reflector to direct heat downward to thaw the ground. It was a cold winter and the frost line was deep. We dug the grave and found a large white June beetle grub four feet deep at the bottom of the grave. Had the beetle only dug three feet deep, it would have frozen.
Trees do not maintain heat to survive winter but have special nature niche adaptations. They remove most of the water from cells to prevent cells from bursting when water freezes. If the cells kept water, it would expand and rupture tissues killing them. Trees must maintain their trunks and branches so they move water to roots and that protects from frost damage. The antifreeze nature of rich sugar water prevents freezing. Desiccation in winter can kill tissues. Bud scales help prevent bud tissue drying by covering delicate tissues that wait for spring. The above ground portion of herbaceous perennial plants dies but living tissue survives in the ground. New spring growth arises from underground tissues. Annuals die except for the seed that carries new life to spring. Wear red flannels and survive until spring.
Natural history questions or topic suggestions can be directed to Ranger Steve (Mueller) at the odybrook@chartermi.net Ody Brook, 13010 Northland Dr, Cedar Springs, MI 49319-8433.
