New York Natural Heritage Program
Fence Lizard
Sceloporus undulatus (Bosc and Daudin, in Sonnini and Latreille, 1801)

Identifying Characteristics [-]
The northern fence lizard (Sceloporus undulatus hyacinthinus) is a small gray or brown spiny lizard measuring 4 to 7.25 inches(10 to 18.4 cm) in length. The belly and sides of males is hyacinth to greenish-blue in color and is bordered by black towards the center of the belly. Males also have a broad bluish area at the base of the throat and this bluish area is also surrounded by black that is often split into two parts. Dorsal crosslines on males are indistinct or absent. Females have a series of dark, undulating crosslines across the back. Females also have a yellow, orange, or reddish coloration at the base of the tail and have a whitish belly with scattered black flecks. Females have small amounts of pale blue coloration at the sides of the belly and throat. The young are patterned similarly to females, but are darker and duller and average 1.6 to 2.25 inches (4.1 to 5.7 cm) at hatching (Conant and Collins 1998).

Characters Most Useful for Identification [-]
The gray-brown coloration, presence of wavy lines across the back, and rough-textured skin due to the keeled scales are useful in separating this species from other New York State lizards.

Best Life Stage for Proper Identification [-]
Adults, juveniles, and hatchlings are all similar in appearance and are fairly easy to identify.

Behavior [-]
Fence lizards are often observed resting on rocks, logs, and stumps in open habitat. When surprised, they will often quickly retreat into rock crevices or under other cover. This species is also known for retreating to a nearby tree, climbing a short distance, and remaining motionless on the opposite side of the tree. If approached again, this behavior is repeated (Conant and Collins 1998).

Diet [-]
Fence lizards eat insects, spiders, other arthropods, snails, and hatchling lizards (Stebbins 1985).
Fence Lizard Images
click to enlarge
The Best Time to See
Fence lizards are generally active from late April until early October and are believed to be inactive during the hottest part of the day in the summer. The species hibernates in burrows, rotting logs, and rock crevices.
Present Active
The time of year you would expect to find Fence Lizard present (blue shading) and active (orange shading) in New York.
Similar Species
  • Five-Lined Skink (Eumeces fasciatus)
    Five-lined skinks occur with fence lizards at all Hudson River Valley sites. This species has five yellowish stripes on a black background and these stripes run lengthwise along the body. Juvenile skinks have a brilliant blue tail. The pattern on older skinks becomes less conspicuous and the tail turns gray. Male skinks develop an orange-red coloration on the jaws during the spring breeding season (Conant and Collins 1998).