So, I googled "A Dead Tree Isn't Dead" and several sites came up. I found out that several species live inside standing dead trees, referred to as "snags". They include:
-birds of prey
-small mammals (bats)
Another site gave me a list of what purposes the snags serve for these species:
-hunting perches (like the eagle that I saw)
-nesting (exterior & interior)
-weather protection (now I know where local birds go in the winter time)
-food source (insects)
-roosting (settling down at night, for diurnal birds, or during the day, for noctural birds, on an elevated spot for the purpose of resting)
I was curious as to the number of snags in the average forest so I googled the question. According to one Washington State study, the average wooded acre contains 16 standing dead trees. A Kentucky wildlife website stated that a wooded area should have a minimum of 6 snags, but ideally 30.
Apparently, a dead tree can stand for decades according to a Pennsylvania Conservation Department website. Hardwoods (oak, maple, birch, dogwood) stand longer than softwoods (pine, balsam, cedar, spruce).
All of the websites seem to agree that dead trees are full of life. So, the next time you take a walk in the woods or a drive down the road, look for those dead trees. They're more plentiful than you think!
Photo courtesy http://3.bp.blogspot.com.