About Hill Forest


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AMPHIBIANS


As determined by a recent survey (Delph, 2010), at least five species of salamanders inhabit riparian habitats within the Forest, although few visitors will have the opportunity to observe these handsome, retiring, and mostly nocturnal creatures which shelter under logs, rocks, and other ground cover near stream banks and other moist areas to avoid dessication and predators.

The Southern Two-lined Salamander (Eurycea cirrigera) is by far the Forest's most abundant salamander. Adults are found in water during the spring breeding season but on land the rest of the year, under rocks or other cover. Adults defend home ranges (about 15 feet in diameter) from other members of their species. Their diet includes wood roaches, spiders, ticks, earthworms, beetles, small snails, grubs, springtails, and other insects, and they are in turn preyed upon by fish, crayfish, owls, and snakes.

The White-spotted Slimy Salamander (Plethodon cylindraceus) is the second most abundant salamander in the Forest. Its range is restricted to the Piedmont and Blue Ridge regions of Virginia and North Carolina, as well as small areas of South Carolina, Virginia, and West Virginia. Some survey data suggest that their decline across this range has been precipitous over the past four decades, but this has not yet been well-established. Like other salamanders they have a mixed diet of small invertebrates including ants, centipedes, springtails, crickets, slugs, and earthworms. Garter snakes and copperheads have been observed to prey on P. cylindraceus. Like all other members of their genus they produce noxious skin secretions as an anti-predator defense.

The Three-lined Salamander (Eurycea guttolineata) is perhaps the Forest's next most abundant species. Adults are mainly terrestrial but are rarely found considerable distances from wetlands. They are most abundant in river-bottom wetlands and in the vicinity of springs, streams, and bogs where seepage keeps the ground moist. They are one of the few plethodontid salamanders that are not territorial and do not defend home ranges. They feed on a variety of invertebrates including snails, arachnids, millipedes, annelids, nematodes, and insects (especially ants). Their primary predators are unknown.

The Dusky Salamander (Desmognathus fuscus fuscus) is a relatively rare denizen of the Forest. Like other salamanders they prey on small invertebrates such as ants, spiders, beetles, sowbugs, caterpillars, earthworms. Their predators include garter snakes, Black-Bellied Salamanders (D. quadramaculatus), and probably raccoons, skunks, opossums, and other small mammals. Dusky salamanders often bite their predators (garter snakes), and autotomize their tails when attempting to flee.

The Eastern (or Red-spotted) Newt (Notophthalmus viridescens) is apparently the least abundant salamander of Hill Forest, although it is widely distributed across the eastern U.S. and is also a common aquarium pet. They can have lifespans of 12 to 15 years in the wild, and may grow to 5 inches in length. It has been claimed that Eastern Newts exhibit homing behavior employing magnetic orientation and possess ferromagnetic material, probably biogenic magnetite, in their bodies. Aquatic adults inhabit pools, ponds, wetlands, sloughs, canals, and quiet areas of streams in upland and bottomland regions, and are found primarily in open, sunny areas. Adults are carnivorous, feeding on any available, palatable prey they can swallow whole. Their predators include fish, snakes, and raccoons. Like other newts (salamanders of the genera Triturus and Notophthalmus) their skin contains the potent neurotoxin, tetrodotoxin, rendering them unpalatable to many animals. The toxin is most highly concentrated in the bright-red immature animals (efts); the brilliant coloration of efts is thus widely considered to be aposematic — an attention-getting characteristic warning off potential predators. The adult's skin (which contains much less tetrodotoxin) is olive green.

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