A Helping Hand

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Published on: Aug. 2, 1999

Last revision: Nov. 3, 2010

Some people call them mountain boomers and others think of them as miniature dinosaurs. Of the 13 kinds of lizards native to Missouri, eastern collared lizards (Crotaphytus collaris collaris) seem to generate the most interest. In fact, their population decline and unique habitat have inspired Missouri's wildlife managers to give them a helping hand.

Collared lizards are distant relatives to iguanas and a variety of lizards that live throughout much of the United States, Mexico and Central America. Their name comes from the fact that both males and females have two dark bars right behind the head that look like a collar.

During their spring breeding season, male collared lizards are brightly colored, having green legs, sides and tail, bright yellow spots on their sides, yellow feet and a bright orange throat and chin. Females are tan and brown with a black collar and, while they are developing eggs, have large orange spots on their sides.

Young collared lizards are light tan with many dark bands and spots. Male collared lizards can grow up to 14 inches in total length and are more colorful than females, which grow to about 12 inches in total length. Collared lizards have the unusual ability to run on their hind legs for short distances to escape predators or intruders. No other Missouri species of lizard has this ability.

Missouri happens to be the eastern edge of the eastern collared lizard's range, which includes much of the southwestern United States and most of northern Mexico. Collared lizards require dry, open and rocky habitats that, in Missouri, are a part of the Ozark landscape we call glades. These dry, open and rocky hilltops and south- or southwest-facing hillsides are similar to rocky habitats found in west Texas or southern Arizona.

Missouri's glades are home to a variety of prairie or near-desert plants and animals, including collared lizards and prickly pear cactus.

In the past 20 years Conservation Department land managers have had a particular interest in glades. A combination of inventories and research have revealed that many glades in the Missouri Ozarks have nearly disappeared, along with their unique plants and animals.

Glades are similar to native prairies and savanna communities in that they must have periodic fire to keep them from being overtaken by trees. Prior to European settlement, glades were likely burned every few years by lightning or fires set by American Indians. A lack of these fires can quickly result in bushes and trees--especially red cedar--colonizing glades.

Collared lizards require habitat that is open and sparsely covered by prairie grasses and forbs and has an abundance of exposed bedrock and flat rocks for shelter. These lizards heat themselves up by basking in the sun on exposed rocks. The open glades and associated native herbaceous plants provide an abundance of insects--an important food for lizards.

Adult collared lizards have large, chunky heads with strong jaws. This allows them to capture and eat large grasshoppers, crickets and--another important prey--other kinds of lizards. Northern fence lizards, skinks and racerunners all can live on glades and become part of a collared lizard's diet.

The Conservation Department is restoring some former glade habitats to their natural condition. Periodic, controlled fire, along with the cutting of cedars and other woody vegetation, has made a dramatic difference and restored these habitats so collared lizards can live and thrive.

But collared lizards need a way to get to these newly restored habitats. Most glades and glade/savanna systems are isolated from each other. Thousands of years ago these dry habitats were connected by a prairie/savanna/glade network that stretched across the Ozarks and allowed western plants and animals to slowly move east.

With a lack of natural fire, this travel network vanished. Small, scattered collared lizard populations became isolated from each other with no natural way for them to migrate to newly restored glades.

Enter a helping hand--in the form of wildlife managers. About eight years ago, wildlife biologists knew of several stable collared lizard populations in southwestern Missouri that could withstand the removal of a few live specimens for a relocation project. Long-term research by Dr. Alan Templeton, of Washington University in St. Louis, had proven that collared lizards can do surprisingly well if a handful are collected from several populations and moved to newly restored glades.

In 1996, we drew up a five-year collared lizard relocation plan and, with the help of several natural resource agencies and Washington University researchers, wildlife managers established new populations in several Ozark counties.

Scientists select only newly restored glades on Conservation Department managed lands for this program.

Herpetologists from Washington University, wildlife biologists with the U.S. Forest Service and the Conservation Department cooperate to gather, transport and release them. Lizards are not released until we are satisfied that selected managed glades are within the species' known range and have a good supply of rocks, appropriate plants and insect prey. We also make sure no collared lizards are already living there. We may release from six to 12 lizards at a restored glade, depending on its size.

Researchers will monitor new collared lizard populations and their restored glades for a number of years to ensure their progress or to make further habitat improvements. This is one of many wildlife restoration programs going on in Missouri. Such efforts will help ensure a healthy, complex and diverse wildlife heritage for future generations.

Giving eastern collared lizards a helping hand is a part of our overall wildlife management goal. We want to be sure that this harmless, colorful and interesting glade-dwelling reptile will be a part of Missouri's Ozarks for a long time to come.

A Collared Encounter

We had just found a smooth, shady rock to sit on, and I was unwrapping some cheese and carrot sticks when I saw him. No more than five feet away, a male eastern collared lizard was moving among the rocks.

The lizard ignored us at first, as he rooted around two basketball-sized rocks for something to eat. We saw him daub his tongue on the rocks and eat a red ant. His tail and back were an astonishing aquamarine. His neck was moderately long, and his throat was brilliant orange in the middle, fading to squash-yellow at the edges. Altogether, the orange spot was about the size of a half-dollar. Black necklaces--the collars around his neck--were so shiny they looked wet.

Then we saw his skin was wrinkly and loose, collapsing on itself in elegant folds. He had four nimble limbs. They were muscled and strangely human-looking, like miniature arms with formidable biceps. He was about 7 inches long and, with his tail, which tapered slowly to a point, he was at least 12 inches.

The lizard had his back to the sun on this June morning. He did a couple of push-ups, gaped his mouth, blinked, then squinted one eye.

He didn't move much, just turned his head every now and then. Once he turned it up--it appeared--to look at a noisy airplane passing overhead. This went on long enough for us to finish assembling our lunch things and peel one avocado.

Suddenly, with great purpose and intent, the lizard zoomed off to the southeast and perched on a rock about 12 to 15 feet away from us. Less than a minute later, a female came crawling up from the far side of the rock, which was about three feet across and two feet high. She had incredibly bright red markings: two red splashes at the base of her ears, then at least six more down her sides. Her tail was the same brilliant aquamarine color as his, but her back was a rich, mottled brown. She was about three-fourths his size. We stopped what we were doing; we were about to see some lizard action.

They mated four times. They sat side by side, close, but not touching. This all happened in full sun. Total time elapsed: about five minutes.

Shade fell across their rock and maybe as that happened, he lost interest or she found that she could no longer egg him on. Or they were just tired. They stopped, and he slid out of sight. -- Charlotte Overby

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