Green anoles (Anolis carolinensis) are native to Florida. These common lizards are an iconic part of the state’s natural landscape, frequently observed in gardens, parks, and natural areas. Their presence is widespread throughout the southeastern United States.
Understanding the Green Anole
The green anole is a small lizard, typically 5 to 8 inches long, including its long tail. They possess a pointed snout and adhesive toe pads, which enable them to climb effectively on various surfaces like trees, shrubs, and walls. As primarily arboreal creatures, they spend most of their time in elevated vegetation.
Green anoles are insectivores, eating mainly insects such as spiders, flies, crickets, and small beetles. They primarily notice and hunt moving prey. One notable characteristic is their ability to change color from bright green to shades of brown or gray, a response influenced by mood, temperature, and stress levels rather than camouflage. Males also feature a prominent pink or reddish dewlap, a throat fan extended during territorial displays and courtship.
The Non-Native Brown Anole
The brown anole (Anolis sagrei) is a non-native, invasive species in Florida, originating from Cuba, the Bahamas, and other West Indies islands. They were first documented in Florida in the late 1800s, likely arriving accidentally as stowaways on cargo ships, particularly in Key West. Since their introduction, brown anoles have rapidly spread, colonizing every county in peninsular Florida by the early 2000s.
Brown anoles are generally 5 to 9 inches long and can vary in color from brown to gray, with some individuals appearing reddish. They often have distinct markings like dark spots, triangles, or a light stripe down their back, especially in females. These lizards are habitat generalists, thriving in a wide range of environments, including urban and suburban areas like yards, golf courses, and parking lots. Their presence significantly impacts native green anole populations through competition for food and habitat. Brown anoles displace green anoles to higher perches and may even prey on young green anoles.
Distinguishing Green and Brown Anoles
Key visual and behavioral distinctions help tell green and brown anoles apart. Green anoles typically display a bright green body color, though they can shift to brown or gray based on their mood or surroundings. In contrast, brown anoles are predominantly brown or grayish, although they can lighten or darken their shade and sometimes have a reddish head.
The dewlap, or throat fan, is a clear differentiator. Male green anoles exhibit a pink or reddish dewlap, which they extend during displays. Male brown anoles, however, have a vibrant reddish-orange dewlap, often bordered by yellow, that they also display to assert dominance or attract mates. Their dewlap can also have various patterns, such as solid, marginal, or spotted.
Head shape is another clue; green anoles generally have a longer, more pointed snout. Brown anoles have a shorter, stouter head. While both species can have a stripe down their back, female green anoles typically have a thin, light stripe, whereas female brown anoles often display a more boldly patterned or scalloped stripe. Brown anoles also have a smooth-edged crest that males can erect on their neck, back, and tail, which is a feature generally absent in green anoles except for a small dorsal ridge males may form when stressed or displaying. Behaviorally, brown anoles are often found on the ground or in lower vegetation, while green anoles inhabit higher perches in trees and shrubs.