Monday, December 3, 2012
CLINTON, Miss. (AP) — On cold, dreary winter nights, tall flashing caution lights along a rocky stretch of the Natchez Trace Parkway will warn drivers to brake for salamanders.
On cool nights when the rain is pouring, salamanders emerge from the ground where they live most of the year and begin to cross from small patches on one side of a two-mile stretch of road looking for breeding ponds on the other, said herpetologist Tom Mann, who leads a group of volunteers who count, identify and escort the salamanders across the busy parkway.
The volunteer group is dedicated to expanding the knowledge of three species — Webster's salamander, the spotted salamander and the marbled salamander — that live between mileposts 85 and 87, just south of Interstate 20 on the Natchez Trace.
The three species are unique and rarely seen by the public. The spotted grows to 9 inches long and lives 30 years or more. The marbled prefers a swampy area and the mother nests atop her eggs.
The Webster's is abundant locally but only lives in 16 small areas in the state.
Despite their differences, they all have an almost primordial need to cross the Trace to breed on the east side of the road. Why the salamanders cross in the specific area is unknown to science, but Mann said the critters who look like scaleless lizards have been performing the same dash through the woods since the ice age.
"At night this is the place to be. This is the magical stretch. Why here? I don't know," Mann said as he stood near milepost 86 on a recent expedition looking for salamanders.
Traffic along the Trace is as unyielding as the salamander's need to breed. Dozens get squashed every rainy winter night, Mann said.
To cut down on the number of fatalities during peak salamander weather, drivers must slow from 50 to 35 mph, said Lisa McInnis, chief of resource management with the parkway. A ticket for breaking the speed limit costs $80 to $500.
"This work is done in unfavorable conditions — at night, often during storms — and alongside a busy section of the Trace. Slowing down not only aids the researchers, but may increase the ability of salamanders and other wildlife to cross, particularly if people are looking out," McInnis said.
The area is filled with limestone outcroppings, ponds and creeks, making it a salamander's paradise, said Mann, who by day is a zoologist at the Mississippi Museum of Natural Science.
Reducing the speed limit is a nominal factor in curtailing salamander deaths, but it does allow scientists to get a better idea of how many are killed crossing the road each year and keeps them safer on the sides of the road. Though the critters are incredibly fast, they spook easily and get crushed just as easily at 35 mph as they do at 50 mph.
"It's not going to save the salamanders," Mann said of the speed reduction. "The idea is that we can do this more safely."
The research, most of which is focused on Webster's salamander, already has yielded some astounding results, Mann said. Webster's is a rare species in Mississippi and in Hinds County and lives only in the small area along the Trace.
Mann said the Webster's species might live in Warren County, though none has been found, and the other two probably do live in the county, but they, too, won't be found unless they're hunted under logs on rainy winter nights.
On a recent rainy night along the Trace, Mann photographed six Webster's salamanders climbing a fence erected to keep the amphibians out of the road.
"No one has ever seen this many of this species climbing," Mann said. "I've sent this photo all around the country to biologists, and it has them excited."
Earlier this month, Mann found six juvenile Webster's under a decaying log in a patch of woods he affectionately refers to as the nursery. Hundreds of pink flags and ribbons there mark logs that frequently are checked for salamanders.
Finding a juvenile Webster's can be rare, even for a trained biologist. Mann spent years looking for a Webster's specimen on the trace before a colleague discovered one by chance.
"This is stuff most people will never see," Mann said as he flipped the log. "No one has ever seen their eggs in the wild."
No one is exactly sure of the breeding habits of Webster's salamanders, though Mann said he and his wife, Dr. Debora Mann, a biology professor at Millsaps College, have a theory.
"I hope we can demonstrate this. There's a lot that has gone into it," Tom Mann said.
In most wooded areas of Warren Country, salamanders are abundant, but they are rarely encountered unless a search of the woods is involved.
— Salamanders resemble lizards but are more closely related to frogs. They have no scales and many species live a portion of their lives in water.
— Many species of salamander feed on small insects and insect larva. Larger species also feed on earthworms.
— The three types of salamanders that live in the area being studied along the Natchez Trace Parkway spend most of their lives underground and prefer to be active only above ground at night.
— Salamanders are abundant around the world, and adults range in size from about 1 inch to about 6 feet. The majority of species are between 4 and 8 inches.
— Though they are abundant in local populations, some habits of Webster's salamander remain a mystery. Their eggs have never been documented in the wild.