Cope's gray treefrog, or lesser gray treefrog, is sometimes confused with the bird-voiced treefrog. One can tell them apart by the orange color on the concealed portion of the leg of the Cope's gray treefrog as opposed to the green or yellowish-white on the bird-voiced treefrog's leg. The color of the Cope's gray treefrog can also change from green or brown to almost white, depending upon changes in temperature and activity. This species of the gray treefrog can be distinguished from the common gray treefrog (Hyla versicolor) by its faster, higher-pitched trill.