Case of the Collared Lizard

Condensed from: Science Daily (Aug. 22, 2011)

Biologist Alan R. Templeton, Ph.D., fell in love with the eastern collared lizard that lives in the hot, dry Ozark glades when he was 13. By the time he returned from graduate and postgraduate work, 75 percent of the lizard populations had vanished. The cover article in the September issue of Ecology celebrates the success of his prolonged effort to reintroduce the lizards and make their populations self‑sustaining.

The Ecology article covers more than 20 years of a 30‑year followup monitoring the reintroduction of collared lizards on Ozark glades in 1984. During this time, 1,662 lizards living on 139 glades on three mountains were captured or recaptured 4,545 times. The major revelation of the work was that burning entire mountains and valleys, called landscape‑level burning, undid ecological damage that was slowed but not stopped by smaller prescribed burns.  In fact, it allowed the lizards to undertake their own expanded restoration effort without the assistance of worried biologists.

The subject of Templeton’s research is the startling eastern collared lizard (Crotaphytus collaris collaris), so called for the darkly pigmented bands around its neck. Missouri is at the eastern end of the collared lizards range, which includes much of the southwestern United States and northern Mexico. Templeton’s acquaintance with the lizard began when he was 13. He was hiking with his Boy Scout troop near Mina Sauk Falls in the Ozarks when they happened upon a glade, and he saw his first collared lizard. “I’d never seen anything like it in Missouri. It was big, it was colorful and it got up on its hind legs and took off running. I just fell in love with them.” Later as a nature counselor at Camp Taum Sauk, he led kids on popular collared lizard hikes.

But then he went off to get his PhD in Michigan and to do research in Hawaii and at the University of Texas. After he returned, Owen Sexton, PhD, a WUSTL ecologist who was studying the life history of collared lizards, told him he was having trouble finding his study subjects. “I said I’d take him down to this area and show him all these collared lizard populations,” Templeton says. “So I went down there and in glade after glade after glade that had collared lizards when I was a teenager, now they’re not there. I was shocked and very concerned. So I started looking into it.”

In 1982, after a rigorous survey of the Missouri glades, Templeton and his colleagues estimated that at least 75 percent of the lizard populations had gone extinct. In some areas of the Ozarks, the lizards had vanished entirely.

“In the Ozarks, you really didn’t have effective fire suppression until after World War II,” Templeton says. “That’s when all the fire towers and lookout towers went in, and the forest service began to fight wildfires.” (Smokey the Bear, the forest service’s mascot, dates from 1944.) Glades no longer swept by fire were invaded by Eastern red cedar (Juniperus virginiana). “Before fire suppression, the red cedar was actually a very rare tree,” Templeton says. “Before fire suppression, the red cedars were basically confined to cliff and bluff faces where the fire couldn’t reach. Now they’re just all over the place.” But why were the glades still healthy when Templeton was young? “Typically in the harsh glade environment, the red cedars are slow growing,” Templeton says. “So there is a 30‑ or 40‑year lag before the consequences of fire suppression catch up to you.

One area Templeton visited when he was surveying Missouri for lizards was the Peck Ranch Conservation Area. The Peck Ranch was a large tract of land bought by a Chicago businessman in the early part of the 20th century as an investment. It was purchased in 1945 by the Missouri Department of Conservation for wild turkey management. By the time Templeton came by looking for lizards in 1982, there were no lizards left at the Peck Ranch. “The ranch manager at the time was a man named Scott McWilliams,” Templeton says. “His mandate was to manage for deer and turkey,” Templeton says, “but he really liked glades; he thought they were beautiful. So when we found that the glades were in rough shape, he said ‘Let’s start restoring some.’ And I said, ‘Sounds good to me.’ ”

At first, Templeton tried local restoration. “It didn’t take long to get the glades back into shape, at least from a botanical point of view,” he says. “Most of the plants adapted to glades put their biomass below the ground because historically the glades burned frequently and anything above the surface was destroyed. The big root systems can survive for decades and once we opened the glade to the sun again, the plant life came back remarkably fast.”

Having restored the glades, Templeton wanted to restore the lizards. He reintroduced lizards to three glades on Stegall Mountain in the Peck Ranch in 1984, 1987 and 1989.  By 1993, however, it was clear that something was wrong. All three populations still existed but the lizards were not recolonizing other glades and no dispersal was taking place between the different populations. As a population biologist, he knew that these small (often 10 or fewer), isolated lizard populations were not stable and would eventually hit a bump and crash again. The problem, Templeton suspected, was that the lizards were trapped on the glades by the dense understory of the woodlands surrounding them, which had not been touched by fire for a long time.

In 1992, a Biodiversity Task Force, of which Templeton was a member, recommended landscape‑level burning. In 1999, the burn management area was expanded to include all of Stegall Mountain and the third lizard population, as well as several adjacent mountains and the interlaying valleys. The transformative power of fire “We did the burn and to tell the truth, I wasn’t really very optimistic about it,” Templeton says. “I thought it was more really to reduce the fuel load, but I was stunned by what it did. Just one burn totally changed the environment. All of us were just shocked at how beneficial it was.

“The fire mainly got rid of the woody understory and thick mats of leaf litter, but it didn’t destroy the canopy trees. In fact, with the woody understory gone, the canopy trees grew better. “The woody understory was mostly exotics, little shrubby trees that came from elsewhere. Once they were gone, the nutrients were released into the soil, and the soil was exposed to more sunlight, the endemics came back. All these endemic herbaceous plants came out of the forest floor and with them came a very abundant insect community.

The burn was in early April and by May and June of that year, the lizards were already beginning to disperse and colonize new glades.”  Having reoccupied the Stegall glades, they went to Thorny Mountain, starting to colonize glades there in 2000. “The glades only support a dozen lizards or so,” Templeton says, “so you always have this problem that just by chance one population might go extinct. And if you’re in a situation where the glade can’t be recolonized, that’s it, you’re done. “After 1994, we still had Stegall glades going extinct, but now they’d be extinct for one or two years and then they’d be recolonized because the woodland has this more open habitat form and the lizards can move through it.

“The Stegall metapopulation is very dynamic,” he says. “Local components of it blink on and off, but at the global level it is very stable.