At Dust Tracks on the Web, Janson Jones posts some interesting observations on green anoles (A. carolinensis) in northern Florida and southern Georgia, where the brown anole (A. sagrei) has yet to invade. To cut to the chase, he finds the green anoles to be larger, to be brown more often, and to perch much lower than green anoles do in central Florida in the presence of brown anoles.
The effect of brown anoles on greens in Florida has been surprisingly poorly documented. Just as surprisingly, very little information exists in the scientific literature on the habitat use, behavior, and other aspects of green anole natural history in places where they occur by themselves. We have almost no useful data on what green anole biology was like in Florida pre-sagrei, nor few data from areas where sagrei does not occur today. Detailed and quantitative studies of such populations would be particularly useful, as well as repeated surveys through time in areas that brown anoles may eventually invade to document what happens when they get there (of course, repeated surveys in areas that brown anoles don’t invade would be important to, as controls). Those of you who live in appropriate areas, get to it!