Imported lizard provides an accidental learning laboratory for biology students

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HAYS, KS -- One of Sheridan Hall's smokers knows the lizards incidentally. The south entrance of the building, on the campus of Fort Hays State University, is where he takes his smoke breaks, and he thinks the lizards have been there since he started work at FHSU in 1998, although there were only a couple then.

Now the little green reptiles are so numerous that it is, at most, only a slight exaggeration to say that they sometimes swarm when he steps out. Until recently, when he found two students catching them, he thought they were some native species happily living among the lilac bushes and flowers.

It turns out that they are Italian.

The two students, who are getting to know Italian wall lizards intimately, have much more than incidental interest. For them, the lizards have academic, scientific, ecological and career value. Since March, they have been catching, cataloging and marking the lizards that inhabit the grounds of three FHSU buildings, Sheridan Hall, McCartney Hall and Albertson Hall.

They only exist in a few places in the United States so far, said Ryan Williams, Plainville junior, and Kyle Tutak, Hays junior. That is Topeka, where they have apparently spread to the entire city, Long Island, NY, which they said is the oldest U.S. population, and possibly in Pennsylvania. The professor for whom they are working, Dr. Bill Stark, associate professor of biological sciences, later said that they may also be in Garden City.

"We're monitoring the population, seeing how fast they are spreading and where they are going," said Williams.

The process is to catch, weigh, measure, determine gender and mark the lizards, recording all the information. The marking is done by using non-metallic paint to daub bright bands across the back, which should last until the reptiles shed their skins. The band nearest the head identifies the building where the lizard was found, one color for each of the three halls and another that simply denotes the lizard was found at a location other than those three buildings. Then three more colored bands give each individual lizard a number: Sheridan Hall 001, and so forth.

Later, they may add to the study an analysis of what the lizards eat and how that affects the insect population.

Toward the end of April, after about two months of research and a month trapping and marking, the preliminary findings are that the males are larger, but, said Tutak, "We had this one huge female" that was apparently highly mobile, as well.

"She was originally marked at Sheridan, but we found her a couple days later at Albertson."

Adults are measuring from about 50 to 60 millimeters from snout to vent (the anus) and about twice that from vent to tail tip. The longest tail so far was 137 mm (an Albertson male). Weight for the adults is in the five- to six-gram range.

"At the end, we should have a fairly good population estimate and age distribution, and an idea of how fast they are expanding, and a gender ratio," said Tutak.

They can tell the gender, in the more mature lizards, anyway, by a line of dark pores on the inner thighs of the back legs. It is pronounced on the males and very faint on the females. "It's the only way to tell gender, the femoral pores," said Williams.

"On juveniles, it's so hard to tell," said Tutak. "Very difficult."

"Definitely difficult," said Williams.

The lizards came to Stark's attention accidentally.
"I was teaching a herp class last spring," he said, "herp" being shorthand for "herpetology," the zoological study of reptiles and amphibians. In a lab period that had dragged on for a while, he sent the students out to add local species to their species lists.

"They came back with them and said, 'We don't know what this is. It's not in our book.' I took a look and said, 'That's because they're not supposed to be here.' "

He said that this particular lizard species has been a part of the pet trade for some time, and the way they are distributed indicates that the lizards are either being deliberately released into the Kansas environment or else pet owners, having lost interest and unwilling to kill them, have freed them.

"The history is certainly there," he said. "It's happened time and time again. Turning them loose in the environment is not the way to go about it. Take it back to the pet store is the better way."

The study is only at beginning to determine the extent of the population and its impact on the environment and on the native species, the prairie-lined racerunner, also known as the six-line racerunner, and its several sub-species. But there may be some damage.

"That's the concern," said Stark. "The potential is certainly there."

"Probably the bigger concern would be as disease vectors," said Stark, diseases that would be foreign to native species, which therefore would have no natural immunity.

Stark's training is in fish, although he does work with amphibians and reptiles, and he has a more well-known local example of invasive foreign species: white perch. This species was imported accidentally with striped bass into local lakes, particularly Cheney Reservoir. In Cheney, they have become so overpopulated that they are stunting as their numbers outstrip the food supply.

At Wilson lake, he said, "The same thing has the potential to happen." He has two graduate students working on the white perch problem.

For Williams and Tutak, the lizard study is perfect preparation for their career aims.

"I like going out and doing field work like this," said Williams. "Field biology, getting out in the field, that's what I want to do."

Tutak also likes the work. "I really enjoy it. It's really good field experience. I'm a fisheries major, so I hope to be doing the same thing, just with aquatics."

"And I'm wildlife," said Williams. "I just don't know what aspect I'll be doing. I don't know if I'll stay with reptiles or go to mammals. It's good field experience, and now that we've done some, we know how to go at it. We know how the basic process works, how to get started and how to prepare."

Though they were working in the spring semester without getting class credit, they plan to enroll as seniors next fall in a graduate-level class, Research and Problems in Biology, and continue their study.

So a local problem that came to light accidentally is now a focus of study, and one of the aims is to find out just how big a problem it might be. Stark said the lizards are probably here to stay. The population has already outpaced the ability to eliminate it.

The species, he said, is "very adaptable and nimble." "The potential is to expand. Whether they would be able to survive out on the prairie, I don't know."

And Ryan Williams and Kyle Tutak are provided with a perfect learning laboratory for their academic and career aims.

"I've got a lot of confidence in those guys," said Stark.

"They've done a good job for us."

FULL DISCLOSURE: Kurt Beyers, assistant director of University Relations and writer of this release, is also the Sheridan Hall smoker in the lead.

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