Gray Tree Frog

This Gray Tree Frog is green, but that is OK.  This frog is able to change colors, from gray to green and from nearly black to nearly white. According to the Minnesota Department of Natural Resources, Gray Tree Frogs create their own antifreeze, by converting glycogen into glycerol, which prevents ice formation within this amphibian--a handy adaptation to Minnesota winter!  I brought this critter into the garage on a bag of charcoal.