Florida’s subtropical climate and peninsular geography support a complex array of native reptile species. The warm, humid environment, combined with numerous international ports of entry, has also created conditions favorable for the establishment of non-native species. Identifying the “most common” lizard requires considering the sheer abundance of individuals, particularly in the state’s highly developed urban and suburban areas. This shift in population dynamics has occurred over the last century.
The Most Common Lizard Species in Florida
The most numerically dominant lizard in Florida is the Brown Anole (Anolis sagrei). This small reptile is not native, having been introduced from its original range in the Caribbean, including Cuba and the Bahamas, likely as a stowaway on cargo ships beginning in the late 1800s. Since its initial arrival in Key West, it has rapidly colonized the entire Florida peninsula and is now found in virtually every county.
The Brown Anole’s widespread establishment has resulted in it surpassing the native Green Anole (Anolis carolinensis) in overall population size. While the native species remains present, especially in less disturbed habitats, the Brown Anole is the lizard most frequently seen by residents and visitors in yards, parks, and around buildings. Its prevalence in areas modified by human activity is a key factor in its status as the most common lizard.
Distinguishing Characteristics and Behavior
Visually identifying the Brown Anole is straightforward, as its appearance differs significantly from the native Green Anole. The Brown Anole exhibits color variations ranging from light tan to dark brown or gray, possessing a robust body and a shorter, wider head. Unlike the Green Anole, the Brown Anole cannot change its base color to bright green, though it can lighten or darken its brown or gray tones.
A defining feature is the dewlap, a flap of skin males extend from their throat for territorial and courtship displays. In the male Brown Anole, this dewlap is a vibrant orange, often edged with yellow, distinguishing it from the native species’ pale pink dewlap. Males also display a low ridge, or crest, that runs along the back of the neck and torso.
Behaviorally, the Brown Anole prefers to perch on the ground, on fences, or on tree trunks, generally staying within a few feet of the ground. Males engage in territorial displays, involving extending their dewlap, bobbing their head, and performing rapid push-up motions. This preference for lower perches is a key difference from the native Green Anole, which typically occupies higher vegetation. The Brown Anole, including its long tail, can range from five to nine inches in total length.
Ecological Success: Why the Brown Anole Thrives
The Brown Anole’s dominance is due to its superior adaptability and reproductive strategy, allowing it to outcompete the native species. It is a successful habitat generalist, thriving in a wide array of environments, including the disturbed and fragmented landscapes of Florida’s urban sprawl. Its ability to colonize human-modified areas quickly is a major advantage over the more sensitive native species.
The species has a high reproductive output, with females laying a single egg approximately every one to two weeks throughout the breeding season. Hatchlings are independent immediately and can reach sexual maturity in under a year, allowing the population to grow rapidly. The Brown Anole also exhibits aggressive behavior, often displacing the native Green Anole from its preferred lower perching sites and forcing it higher into the vegetation.
Scientific studies show that Brown Anoles are predators of the native species’ young, actively eating Green Anole hatchlings, which further suppresses the native population. The multiple introductions of the species from various parts of its native range provided a high level of genetic diversity. This genetic richness enhanced the Brown Anole’s capacity for rapid adaptation to Florida’s climate conditions, securing its place as the state’s most abundant lizard.