A male brown anole (Anolis sagreia) with dewlap extended
I first found out about the brown anole (small lizard native to the Caribbean) when I was in my Zoology class in 2008. At that point, none of the professors at my college, located in Southeastern Georgia had never seen one. They were something only seen in Florida, which has an ever-growing issue with invasives. Since then, they have become ever-more common, and earlier this year I did, in fact, see one on my college campus.
Invasive species are always dangerous because the true extent of their effect on a habitat will not reveal itself until the animal, or plant or whatever it may be, has been in the area for a significant period of time. Since these lizards have only been in Georgia for a short time, it is unclear what their presence will do to the native wild life.
Potential cause for alarm comes from the brown anole's relative, the green or Carolina anole (Anolis carolinensis, seen left). Since the brown anole's territory is expanding, more and more pressure will be placed on the greens, as their diets are quite similar. Also, and I have seen this first-hand during a trip to Florida, brown anoles will eat green anoles. In that same location, brown anoles clearly outnumbered green anoles. Even though this seems to imply that the browns are taking over, it is difficult to tell. It could just be that the greens are better able to blend in with their surroundings and thus were less easily observed. They are able to change from green to brown (the origin of their nickname "American chameleon") and are thus able to blend in very well. Or, it could in fact mean their numbers are dropping.
What does the future hold for these lizards? Will green anoles become extinct? Will the two species be able to coexist? Who knows. Unfortunately, we can only wait and see.
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