Robert Jaeger leads the hunt through dense woods in southwestern Virginia near Mountain Lake. Occasionally,he bends to brush away dead leaves or poke into the rich tangle of organic matter littering the forest floor. His quarry is the small and elusive salamander. Though seldom seen, salamanders are the most common land-dwelling vertebrate (animal with a bony skeleton) in the United States. In some regions of these Appalachian Mountains, their combined weight exceeds that of all birds and mammals combined.
Jaeger lifts a rotting log and spots two thin, miniature dragons, each with a red streak down its back. One salamander had been lurking under one end of the log and the other at the opposite end.
"Redbacks," Jaeger exclaims. "If this were the mating season, they would both be in the middle."
Jaeger is a biologist at the University of Southwest Louisana and has devoted the past 28 years to studying redback salamanders, the most common species of these extraordinary creatures inhabiting this country. Jaeger comes to the Appalachians -- the world center of salamanderdom -- regularly to do research. "I'm only beginning to understand them," he says.
With slender bodies, long tails and legs splayed like reptiles, salamanders often are mistaken for lizards. They are sometimes called spring lizards in parts of the Appalachians.
In fact, salamanders, which range in length from two inches to nearly six feet (the Chinese giant salamander), belong to the very different class called amphibians They are the nearest living descendants of the first vertebrates to leave water and live on land. Reptiles evolved from amphibians.
The word "amphibian" comes from the Greek amphibios for "having a double life," a reference to the creatures' ties to aquatic and terrestrial environments. Salamanders are related to frogs and toads and, like them, cannot stray far from wet places.
Unlike reptiles, salamanders have clawless toes, gelatinous eggs and a smooth, sometimes slimy skin rather than scales. Lacking the reptile egg's shell, a salamander {lays its eggs} leaves or rocks or in rotting, humid tree stumps.
As befits one of the most ancient lineages of boned animals, the salamander clan is thought to have evolved in one of the world's oldest mountain ranges -- the Appalachians. The southeastern United States, particularly the Appalachians, is home to more individual salamanders as well as a greater diversity of salamander species than anywhere else. Of the 10 salamander families known worldwide, nine are found in this country. Five occur nowhere else.
Although no one knows how many salamanders there are, one estimate puts their numbers in North Carolina alone at 1.5 billion.
"Few people realize how important salamanders are," says Joseph Mitchell, a University of Richmond biologist. "Because they are both predators of insects and other invertebrates as well as prey for mammals, birds and snakes, salamanders play pivotal roles in the energy dynamics of forest ecosystems."
Nevertheless, salamanders are shy, secretive creatures rarely seen by people not specifically looking for them. Most hide during the day in rotting tree stumps, burrowed in the ground, or under rocks, leaves or logs. They typically emerge only on rainy, foggy or misty nights to feed or mate. The best time to look for salamanders is shortly after dark, especially in spring and fall when many migrate to ponds to mate and lay eggs.
One exception is the red eft, the juvenile stage of the red-spotted newt, a common salamander that spends its adult life in ponds. Unlike other salamanders, red efts walk out in the open during daylight as if they hadn't a care in the world. The reason: Their skin is so poisonous that predators quickly learn to leave them alone.
Newts are semi-aquatic salamanders, moving in and out of water at will. Other aquatic salamanders sometimes go by other names, such as sirens, mudpuppies, hellbenders, axolotls and amphiumas, which sometimes are called conger eels.
Not only are most salamanders secretive, they also are small and hard to spot even when active. Most are less than six inches long. One exception is the hellbender, a stream dweller found in streams of Appalachia, the Ohio River valley and the Ozark Mountains. Hellbenders can reach two feet in length.
These giant salamanders often dine on crayfish, which they suck into their mouths. Rather than swallow their prey immediately, hellbenders wait while the spiny crayfish tries to escape. When the luckless crustacean turns to head out of the mouth, thus aiming its spines in that direction, the hellbender gulps it tail first.
As long as 13 inches, tiger salamanders are the world's largest land-dwelling salamander. They are found from the Appalachians to the desert West. Although their color varies from place to place, most have yellow spots interspersed with tiger-like stripes.
As juveniles, salamander hatchlings go through a larval stage. They eat aquatic insects, worms and microscopic organisms. But, in Arizona, some juvenile tiger salamanders grow larger than others and develop wider heads and enlarged teeth. Thus equipped, they eat other tiger salamander larvae.
Closer to home, Jaeger's redbacks are perhaps the most common salamander of the eastern United States. They are found in forests and wooded back yards from southern Canada into northern Georgia and west into Illinois, Wisconsin and Minnesota.
Redbacks are one of 2 salamander species that are the only vertebrates with neither lungs nor gills as adults. Instead, they absorb oxygen and emit carbon dioxide through their skin and mucous membranes in their mouths. For these tissues to allow gases to pass in and out, they must be wet. That is why most salamanders need humid environments. There are 170 other species, and they either have gills throughout their lives or develop lungs when mature.
Redbacks exhibit other unusual characteristics. Females, for example, select mates by smelling the male's feces. Apparently, Jaeger says, they want to know what prospective suitors have been eating. Unlike tiger salamanders, redbacks spend their larval stage in their eggs, hatching almost fully developed as adults.
Smell also is important to mountain dusky salamanders, which live in the Appalachians from New York to Georgia. Strangely, mountain duskies from one region do not court or mate with those from another. Although mountain duskies look alike to humans, that doesn't matter much to the salamanders. "They operate on chemical cues," says Stephen Tilley, a biologist at Smith College. It is possible that some of these salamanders, now classified in one species, actually belong to several.
Unlike redbacks, axolotls are one of several salamanders that refuse to grow up. Found in Mexican lakes surrounded by hot, dry land inhospitable to other salamanders, axolotls spend their entire life in water. They retain larval gills and a tail shaped for swimming. They even mate and lay eggs while otherwise retaining juvenile characteristics.
When salamanders mate, they often do so in huge numbers. Scientists at the University of Georgia's Savannah River Ecology Laboratory in Aiken, S.C., have been monitoring marbled, mole and tiger salamanders since 1978. By placing fences and buckets around temporary ponds where the salamanders mate and lay eggs, the scientists have been able to track the amphibians' numbers.
In some years, the scientists have caught hundreds or thousands of salamanders on a single night. In others, few were caught. The reason is rain. "We saw no population trends that were not readily explainable by natural factors related to drought," says Joseph Pechmann, an ecology lab researcher who heads the study.
Even if few salamanders are caught in any year, it does not mean the rest are dead, Pechmann adds. Not all salamanders mate every year, even when conditions are right. If rain fails to come or falls at the wrong time, salamanders simply stay in underground burrows until better weather arrives.
Elsewhere, though, some scientists express concern that clear-cut logging of Appalachian and other forests may threaten salamanders. James Petranka, a biologist at the University of North Carolina at Asheville, estimates that 14 million salamanders -- about 1 percent of the population -- are killed every year in his state by logging.
Because clear-cut logging removes vegetative cover, it allows drying winds and sun to penetrate to the normally shaded forest floor. Eventually, it also removes leaf litter that provides cover for many salamanders. "Salamanders are really vulnerable to logging," Petranka says. "They can't run away or hide. Salamanders are knocked out when their moist habitats are lost."
Most salamander species live in such widespread areas that, even if some are lost because of logging, others will migrate in from neighboring woods as the logged forest recovers. Of particular concern, however, are those whose range is limited to a single or a few mountains, valleys, caves or streams.
One is the white-spotted or Cow Knob salamander found only in Virginia's George Washington National Forest. To protect it, the U.S. Forest Service has declared a 43,000-acre site above 3,100-foot elevation to be a special biological reserve. No new roads, building or logging are allowed, Mitchell says.
Similarly, the forest service has adopted a recovery plan that identifies critical habitat for the endangered Cheat Mountain salamander in West Virginia's Monongahela National Forest. The U.S. Fish and Wildlife Service has arranged a habitat conservation plan with International Paper Co. to protect 4,500 acres of company-owned timber land for the threatened Red Hills salamander in southern Alabama.
Such conservation efforts offer hope that many salamander species will hold their own. For those who enjoy exploring our local forests, examining rotting tree stumps, peering into streams or poking around under rocks, logs and leaves, that is good news. Jeffrey P. Cohn, a freelancer who says he leaves no stone or log unturned, writes often on environnmental and wildlife issues.
Keeping Salamanders as Pets
If a salamander follows you home, you can try to keep it briefly and observe its behavior.
Although some salamanders are difficult to keep in captivity because supplying the small prey they eat is a problem, others can be maintained easily in terrariums. Most newts eat various small fish, tadpoles, worms and chopped meat. Tiger, marbled and other so-called mole salamanders like crickets, slugs and worms. It's a good idea to provide any captive salamander rocks, bark or stones under which to hide. Redback and other woodland salamanders need moist conditions and
soil for burrowing. Newts are only partly aquatic and need some dry land in case they decide to leave the water. For hellbenders and other purely aquatic species, make sure the aquarium is large enough to accommodate their size.
Be careful what animals you put in with salamanders. Snakes and large fish will eat them, and large salamanders will eat smaller ones. Long-term survival of salamanders in captivity is problematic. After a few days or weeks, it's a good idea to release the animal, putting it back in the same habitat from which it came.
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