LIZARDS ARE HERE TO STAY
Italy, and Cincinnati, Ohio, are seldom mentioned in the same sentence.
One reason to do so is that both are home to a reptile known as the
common wall lizard.
about U.S. lizards, the wall lizard has become a standard entry because
it's become naturalized, meaning it is a non-native species that is
reproducing successfully and maintaining sustainable population levels.
arrived on the North American continent more than 60 years ago. They
thrive on outdoor walls of brick or concrete with plenty of crevices,
presumably a preadaptation from living in rocky habitats of cliffs and
boulders in their native range of southern Europe.
handsome creatures, reaching lengths of over 9 inches from nose to tail.
Like many birds, the males become more brightly colored during the mating
season, displaying a row of bright blue spots down their sides.
local habitat is perfect for the wall lizards; so is the climate. Milan
and Cincinnati could use the same weather map much of the year as daily
and seasonal temperatures, rainfall, and humidity are similar.
lizards arrived in Cincinnati they may not even have known they had
left Italy. As often happens with invasive species, they could have
become exceedingly unpopular with local residents.
to an upcoming publication by Jeff Davis, wall lizards "are beloved
creatures, and (the residents) enjoy seeing them scurry about their
landscape." Jeff is an Ohio herpetologist who has done more research
and is more knowledgeable about the species than anyone else I know.
I talked with Jeff about wall lizards. The most plausible story of how
a European lizard made its way to Ohio involves a boy named George Rau,
who returned home to Cincinnati from a vacation in northern Italy in
the early 1950s.
another youngster of that era, George collected critters. While he was
on vacation in Milan, he caught some lizards that were common in the
he brought 10 of them home with him. He released them in his Cincinnati
neighborhood, which proved ideal habitat because of the stacked rocks
and brick retaining walls in the hilly residential areas.
wall lizards probably number in the hundreds of thousands today in densities
as high as 1,500 per acre in some areas. How an animal survives and
how widespread it becomes in a region depends on a variety of ecological
it and how it disperses over the landscape can be critical. Cats and
cars are primary sources of mortality. Nonetheless, although wall lizards
are subject to the same hazards as other wildlife when crossing streets,
they are apparently expanding their geographic range beyond Hamilton
been documented in another county in Ohio as well as south to Kentucky
and west to Indiana.
his colleagues have confirmed the presence of wall lizards in more than
100 localities and investigated how they might have gotten to various
places. Some undoubtedly have been carried to other areas on purpose
or as stowaways.
that several survived transport from Italy to Ohio attests to their
hardiness, so taking a trip of a few hours in a vehicle should be no
problem. He also has a record of individual lizards sitting on logs
that floated down rivers.
wildlife often disperse unintentionally during such rafting adventures
and end up downstream, far from their point of origin.
introduced species become hardcore invasive pests that cause problems
for other wildlife. Most are probably inconsequential and are never
heard from again after a brief visit as a tourist.
honey bees, camellias, and wall lizards, have even earned stellar reputations.
They not only do no harm to local wildlife, they have become species
that people actually want to have around.
wall lizards will soon offer themselves up to become "beloved"
in communities far away from the hillsides of Cincinnati.
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