One of the marvelous benefits of working as a naturalist with children is utilizing dozens of extra eyes in exploring a habitat. I often meet Odessa kids in Comanche Park, a draw filled with trees (elm, Osage orange, mulberry, locust - trees escaped from ornamental plantings via prolific seeds). A fine asphalt trail snakes along in the "riparian woodland." The trail is bordered by thousands of dinner-plate sized "rocks" (chunks of asphalt from a previous trail.) Students discover that the rocks can be turned over and that pillbugs, scorpions, pseudoscorpions, stinkbugs, earwigs, snails, beetles and lizards abound. In the spring on chilly mornings, a lizard can be found under every 10th rock. Southern prairie lizards are the most common, but we have found as many as eight Great Plains skinks in one morning.
Most of the time, Great Plain skinks are fossorial, living underground. After rains, they often emerge and sometimes go cruising about in the early morning. They dig up beetle larvae, eat smaller lizards, small bird eggs, earthworms, crickets and grasshoppers. Chuck Henderson once found one in his backyard eating a mouse. It took up residence under one rock in his yard, and remained there for more than a month, so he became Chuck and Nancy's "pet." Skinks are usually found on the ground, but one descending a tree that I was leaning against startled me.
Our best Great Plains skink at the Comanche Park Trail was a female, curled around a clutch of eggs. Even when poked, she did not move, just tightened her body closer around her precious eggs. As soon as they hatch, however, she abandons them. Great Plains skinks are fearless, usually snapping at a bothersome finger - and if they latch on, they can draw blood. I have heard people call them Gila monsters, because the biggest can be more than a foot long and as big around as a good sausage. There is one characteristic that Gila monsters and skinks share - both have scales with bony plates, called osteoderms. No other lizard has this feature.
I used to take a specimen or two for a terrarium and later let them go. I once placed one with a southern prairie lizard, due to lack of space. Big mistake! A day later, only the skink remained. Another time I placed an adult with a young one, the young one still possessing a black body and blue tail, with white spots on the lips. The adult chased the colorful young one, and within a few hours had removed a half-dozen scales, so I rescued the little one.
On one visit to Comanche Park, the kids caught three skinks, of different sizes and different color patterns. I assumed they were all Great Plains skinks. I did not really look closely at them as I prepared separate terrariums for each. That evening an 11-year-old student was taking a break from a different project and sat down to watch the skinks eat crickets. In a few minutes he came into my office and asked if there weren't two species. I followed him into the lab and listened as he pointed out that one had a much longer tail compared to his body and proportionally much smaller legs.
By golly! So what was it? We got the books out. Color was not a good method of identification, or so it seemed, but the body shape was. The strange skink was a variable skink, which had only been found at Lubbock, in the Guadalupe Mountains, at San Angelo and at Chandler Ranch (located at the junction of the Pecos River and Independence Creek) - or so I guess from the map of its range in Texas. It survived five months, until I accidentally put it in a terrarium with a large Great Plains skink. Its slightly mangled body is now in the Sul Ross University Collections. Books with distribution maps for the species now have a dot in Midland County. We have now found variable skinks in Howard County and Midland County, but we did not keep a specimen, so the books will not reflect our findings.
It is exciting to be able to add to the distribution information of an uncommon organism, but it was equally exciting to discover an 11-year-old with such discriminating powers of observation.
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