Thursday, February 21, 2008
There are three skinks that can be seen from the boardwalk at the Audubon Center at Francis Beidler Forest. However, identifying which skink you have just seen can be tricky. All can be similar in size and coloration at various stages in their life cycle. What you really need to do is catch the lizard!
The three species of skinks at Beidler Forest are the Broad-headed Skink (Eumeces laticeps), the Southeastern Five-lined Skink (Eumeces inexpectatus), and the Five-lined Skink (Eumeces fasciatus). You can quickly identify the Southeastern Five-lined Skink by looking under its tail (not a regenerated portion) and observing the size of the scales. If it is a Southeastern Five-lined Skink, the scales will all be about the same size. If the scales are not about the same size (the middle row will have enlarged scales), then you are holding a Five-lined Skink or a Broad-headed Skink.
Usually, an adult Broad-headed Skink will be much bulkier as it is North America's second largest skink. However, younger specimens may resemble adult skinks of the other two species previously mentioned. Additionally, the orange head is shared by adult males of other species during the mating season. Having eliminated the Southeasten Five-lined Skink as a possibility, the Broad-headed Skink and the Five-lined Skink can be differentiated by the presence or number of certain scales on the sides of their heads.
The labials are the similarly-sized scales along the upper portion of the mouth moving back from the tip of the head. A Five-lined Skink has four labials while a Broad-headed Skink has five. Continuing in a straight line to where the scales on the head transition to the scales of the body, one can find the postlabial scales. The Five-lined Skink has two of these scales while the Broad-headed Skink has none.
The blue tails of the skinks in the images signal that these individuals are juveniles and not a threat to mates or territory. It saves on unnecessary postering or fighting.
As we would likely starve if our survival depending on successfully catching skinks and the embarrassment of failure before a large group of school kids would be crushing, we generally make no attempts to capture skinks for positive identification.
Posted by Swampy at 4:09 PM