Podarcis muralis translates into “wall lizards,” has long been a subject of local Cincinnati lore. Until recently, the details of their arrival were sketchy, but it is now known that a child of the Lazarus family, owners of the Lazarus department store chain, pocketed some lizards while on a vacation in northern Italy in the early 1950s and slipped them through U.S. Customs undetected. The boy, George Rau, let about 10 of the lizards go at the family’s home in the O’Bryonville neighborhood of Cincinnati.
In the 50 years since, the lizards not only survived but thrived, spreading about six miles eastward and into some neighborhoods to the north, including onto Xavier’s campus. Their main venue for mobility: the city’s railroad tracks.
“The Lazarus lizard is interesting because it came over and made it even though it’s a foreigner,” Hedeen says. “But the European wall lizard is a very urbanized lizard. Centuries ago it moved out of the rocky Alps and adapted itself to the cities because people built with rocks and mimicked the landscape. It had already jumped from a natural landscape into a humanized, urbanized landscape, so coming to Cincinnati in the pocket of a child was no change at all.”
Hedeen’s academic interest in the lizards is to learn how they survived in a foreign environment. It doesn’t happen often, he says. Most foreign species die off because of two factors: a hostile environment and competition from native species.
The Lazarus lizards encountered neither. In an article published in Herpetological Review, Hedeen points to the nearly identical climate, rainfall and habitat of northern Italy and Cincinnati as the major factors that allow the lizards to survive. On a visit to southern Europe, he observed the lizards clinging to stone walls, sides of houses, piles of rocks and railway embankments. In Cincinnati, they are seen on stone walls, limestone rock outcrops and railway trestles.
In addition, though, lack of competition from Cincinnati’s three native lizard species left the region up for grabs by the Italian conquerors. The native eastern fence lizard and the broad-headed skinks prefer slightly different terrain than the dry, rocky landscapes of the Lazarus lizards. But development in Cincinnati has ushered the local lizards into ever-shrinking locales such as the forested California Woods Nature Preserve on the eastern edge of the city.
Now Hedeen visits the preserve to see if the Lazarus lizards have reached the skinks’ habitat. They haven’t met up yet, but he expects it’s just a waiting game as the lizards have been spotted just a few hundreds yards from the park. When they arrive, it won’t be pretty.
“If Lazarus moves into the forest, it’s bad news for the skinks,” Hedeen says. “Two different species will not intermingle and over time, one will displace the other. At the boundary between their two habitats, there might be some competition in which Lazarus can still win, or the native skinks can hold their own.”
How the Lazarus lizards are getting to the nature preserve is another topic of study for Hedeen. Initially, the lizard population exploded throughout parts of O’Bryonville, which became known as Lizard Hill, and then spread into nearby neighborhoods. But their most prevalent migration has been eastward via the old Pennsylvania Railroad tracks at the bottom of the hill.
“They hit that track and said this is nice because of the rock ballast and the dried-out ties, and they walked along the tracks. Each generation moves farther down the track,” Hedeen says. “They ride these rails. At some point, the European wall lizard will have moved from the Atlantic to the Pacific, just like the starling, and we’ll study the effect on the natural environment.”
That trip might take a few more decades. In the meantime, Hedeen, who’s retiring this spring, plans on following the little creatures into the skinks’ territory and writing about the encounter. In the world of science, the lizards’ survival is worthy of note, he says, because it’s an unnatural migration.
“The invasion of a foreign species in a northern location like Cincinnati is considered an oddity, because it’s rare for a temperate organism to get across the Atlantic Ocean,” he says. “It’s the only foreign reptile to have made it in the Midwestern U.S.”