Hibernation around the corner

Animals have many ways of coping with the cold weather and lack of food available during the winter. Some animals migrate to warmer climates, others build shelters and store food, and still others enter into an inactive state called hibernation where their heart rate slows down. True hibernators appear to be dead since they do not move and their body temperature is close to the outside temperature. Examples of true hibernators are ground hogs, certain bats, amphibians such as frogs, reptiles (snakes), and many insects.

Some animals go into a state of torpor which means that their heart rate slows and their body temperature lowers but they can and do wake up to feed. Examples of animals that go into this mini hibernation are bears, skunks, and raccoons. Still other animals know when to "chill out," escaping to their den or nest when the weather gets bad. Examples of these animals are squirrels, chipmunks, beaver, and many birds.

Oak leaves

Did you ever notice that oak forests tend to have much more leaf litter on the ground than other forests? This is because oak leaves decompose at a much slower rate than most other leaves. Oaks, beech and chestnut leaves have higher tannin and lignin levels than most other species of tree, and these chemicals are preservatives. This is one reason oaks, beech and chestnut belong to the same "family" of trees (Fagacea). Left alone it may take three to four years for oak leaves to break down. If you are composting oak leaves you can speed up this decomposition by shredding them or tilling up the ground. Another way to speed up this process is to mix the leaves with nitrogen rich compost such as manure or coffee grounds.

Migration

Fall migration brings many birds, large and small, through the Mid-Atlantic. A noted local point for raptor viewing is the Washington Monument atop South Mountain, off U.S. 40A about 10 miles from the Frederick Towne Mall. Golden Eagles are often seen at Washington Monument State Park in early November. With a wing span of up to seven feet, Golden Eagles are among the largest raptors we see in Maryland. The adults have golden fringed feathers on the head and neck. Females are larger than males, and juveniles show white instead of golden highlights. Golden eagles help control rodent populations. Other raptors and hawks can also be seen this time of year.

The best conditions for eagle and hawk watching are a couple of days after a cold front has passed, with fair conditions and a prevailing breeze from the North and West. Neither calm nor stormy days are best for migrating raptors.

Nature Notes for 11/8/2009