By Ranger Steve Mueller
My oldest daughter and I ventured into the night when we were on our way somewhere. She asked, “What’s making that sound?” We listened and heard a chipping nearby but could not see what was making the sound. The outside light was on but revealed no birds or other animals.
We used our ears to locate the sound. It was coming from near the bird feeder but nothing was there. We moved closer and the sound was definitely coming from the feeder with no animals on it. I lifted to cover to see what might be inside and out “flew” three Southern Flying Squirrels. Not only were the squirrels surprised, so were we when life exploded from inside the feeder.
The flying squirrels do not actually fly. They glide on parachute skin flaps that stretch between fore and hind legs. They also have a flattened tail that helps with buoyancy in the air and aids as a rudder. Large bulgy eyes help in the deep darkness of night. These small mammals are truly nocturnal and are seen only in daylight when disturbed from a shelter cavity.
They depend on dead hollow trees for survival. Food, water, and a few acres of appropriate living space are necessary. Without cavities for shelter they do not do well. People often want to “clean up” yards of dead standing trees. I suggest leaving dead trees stand unless they are in a location that may result in injury to people or damage to the house when they fall.
As director at Howard Christensen Nature Center (HCNC), I removed dead trees near trails where they could present a danger. I have recommended current HCNC landscape managers to allow most dead trees to stand. People have a tendency to want them for burning in fireplaces or woodstoves. It is usually better to take live trees that are crowded too close together. Thin live trees instead of taking dead ones. The remaining live trees will grow healthier with more vigor in a thinned forest. After cut trees are aged for months to a year, they make better firewood than do dead trees. Dead trees lose substance with time and provide less heating capacity.
It is not just squirrels that need dead trees for survival. There are many species of mammals, birds, and insects that need the shelter gained from dead trees. A forest is not healthy without a large number of standing dead trees. During the extreme cold we have been experiencing, bluebirds huddle together in hollow tree cavities to survive the night. Northern Flying Squirrels are more common in the Upper Peninsula but could possibly get this far south. To tell them apart one would probably need to have them in hand to examine the color of hair bases.
There are many living things, like Southern Flying Squirrels, that are never or seldom seen. Life abounds at HCNC and Ody Brook because dead wood is allowed to stand. Your yard can support a great amount of life when managed well. Life in nature niches depends on a healthy supply of the dead.
Think food, water, shelter and appropriate living space. Provide conditions that allow nature to provide the food, water, and shelter. You can supplement with birdseed, nest boxes, and birdbaths but the main source of life support should come from what nature provides for free in a well-managed landscape.
Natural history questions or topic suggestions can be directed to Ranger Steve (Mueller) at firstname.lastname@example.org Ody Brook, 13010 Northland Dr, Cedar Springs, MI 49319-8433. Submitted 7 Feb 2014