Rephrased, clarified question re black squirrels and their coats???

My South-Central Michigan neighborhood is full of oak trees and the locally predominant species: gray squirrels. In late summer three what are known here as black squirrels moved into my yard: larger than the tiny red squirrels, much smaller than grays, and considered more aggressive, tending to drive out grays as they move in.Two were actually black;one a dark charcoal. In October one developed a bald saddle on neck/shoulders which grew much larger; the tail hair thinned as bald spots grew. The charcoal went next, then the last black one. The first's remaining coat went pale gray. I suspected mange, and became concerned about other squirrels and my dogs, but figured that bald squirrels with short food supplies laid in would probably not survive winter.





Now all three have full coats; the two light coats look sparser than the black. I never knew mange just to reverse itself. Is this coat change normal for black squirrels? Sign of a disease dogs could get? Something else?





Thanks!Rephrased, clarified question re black squirrels and their coats???
There are four species of squirrels in Michigan - gray, red, fox and flying. What you are describing is the melanistic form of the gray squirrel.





Black squirrels are not a separate species from gray squirrels. They are simply hypermelanistic individuals of the gray squirrel species. This means that they have more pigment than normal individuals. It is the most common mutation affecting gray squirrels.





Notoedric mange has been reported in your area in both fox squirrels (which may be your large species) and gray squirrels. This type of mange often spontaneously disappears if the affected animals survive long enough (see the web page below for lots more information)





http://www.michigan.gov/dnr/0,1607,7-153鈥?/a>





Dogs can contract this type of mange, but it is relatively easy to cure with ivermectins. Your dogs would probably need very close contact with the squirrels to contract the disease, and you should prevent this (not least because squirrels can carry a lot of other diseases).