Salamanders, Toads, and Frogs
The southern Appalachian Mountains have long been
regarded as the home of a large variety of amphibians. It is an ancient
region of heavy precipitation and numerous streams and rivulets. Within
the National Park alone the vertical distance between the lowest and
highest points of land is almost 5,800 feet. The plant-life is dense
and rich in the number of species; here one finds Canadian-zone stands
of spruce and fir on the higher summits grading down to sweetgum and
sycamore at the base. These mountain forests are the habitat for at
least 27 kinds of salamanders, ranging from the pigmy salamander, less
than 2 inches long when mature, to the big hellbender, which may grow to
29 inches. The pigmy salamander is strictly terrestrial and is found
only in the high-mountain forests, whereas the hellbender is entirely
aquatic, living only in the warmer low-altitude streams.
The red-cheeked, or Jordan's, salamander is of
exceptional interest, since its entire range appears to be restricted to
Great Smoky Mountains National Park. Adults average about 4 inches in
length. With the exception of reddish or orange cheek patches, the
coloration throughout is blackish. Like the pigmy salamander, the first
specimens of which were discovered in the Smokies,
Jordan's salamander is a land form, living under
rocks and logs at the higher altitudes.
While most species of salamanders will lay eggs
during the spring, the hellbender will lay her string of eggs in summer;
the marbled salamander, in the autumn; and the attractively marked
spotted salamander, in the winter. It is not unusual to find the
jellylike egg-clusters of the spotted salamanders in temporary woodland
pools in January.
Numerous streams and rivulets make this region the
habitat for many salamanders. This stream is the West Prong of the
Little Pigeon River.
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On certain warm rainy nights in early spring, large
numbers of salamanders may be observed upon the wet macadam-surfaced
road which crosses the Smokies from Cherokee, N.C., to Gatlinburg, Tenn.
Such an emergence is described by Dr. Willis King in his report "A
Survey of the Herpetology of Great Smoky Mountains National Park." (See
"Selected Bibliography.") In his discussion of the large mountain purple
salamander, which occurs mostly at altitudes above 2,500 feet, Dr. King
writes:
On the night of April 20, 1937, Mrs. King and I were
driving from Gatlinburg to Waynesville between 8 and 9 p.m. It was a
warm foggy night, following a period of showers. On the Newfound Gap
road, Tennessee side, between 3,500 and 5,000 feet elevation we saw at
least 200 salamanders of this species crawling about on the road. They
could be seen at considerable distance because of the contrast
of their light bodies on the black surface of the
road, but even more striking was the reflection from their eyes. The
presence of so many of these comparatively uncommon animals made the
observation all the more interesting.
Although an emergence of salamanders in April appears
in order, as many as eight species of amphibians (five salamanders, two
frogs, and a toad) have been observed on this same road on a wet night
in November, and nine species (five salamanders, three frogs, and a
toad), on a day and night in December. On the latter occasion
(December 3, 1950) three specimens of mountain purple salamanders which
had been killed by passing vehicles were collected; one of these was a
female with a large quantity of eggs in the body cavity. How soon would
these eggs have been laid if the animal's life had been spared? Much
remains unknown concerning the natural history of a number of our
salamanders.
The presence of these amphibians at night on the wet,
macadam-surfaced road may be due, in part, to the temperature and, in
part, to the food which is available there. Roads of this kind are
likely to be warmer than the ground on either side and, when
wet, serve to attract a considerable number of earthworms and other
small invertebrates, where they are readily secured by the salamanders.
But such a situation is hazardous to all concerned, for not only passing
vehicles but various predators kill the slow-moving salamanders once
they leave the protection of the nearby forest. Since the remains of
salamanders have been found in the stomach of a screech owl, and since
screech owl remains have been found in the stomach of an
opossumboth the owl and the opossum having been killed by passing
cars along the roada chain reaction such as the following is
within the realm of possibility.
The setting is the main transmountain road in the
Great Smokies on a warm, rainy night: (1) Earthworms become stranded on
the road; (2) a salamander appears and begins feeding upon the
earthworms; (3) a screech owl, while patrolling the road, discovers the
salamander and alights to feed upon it; (4) a passing car kills the owl;
(5) an opossum finds the dead owl in the road and, while feeding upon
it, meets a similar fate. One could go on and extend the chain with a
fox feeding upon the opossum, but since Reynard in all probability
would carry the opossum into the nearby woods before beginning his meal,
the sequence will end there.
The snoring drone of the gray treefrog is one of
the late-spring and summer sounds in lower altitudes of the park.
Courtesy, Isabelle Hunt Conant.
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The American toad, Fowler's toad, and 10 species of
frogs occur within the park. Unlike the salamanders, which are
voiceless, frogs and toads are well endowed in this respect, and their
singing may be loud and persistent. These animals are the first to give
voice to the coming of spring, and this may be as early as January in
the case of spring peepers, chorus frogs, and wood frogs. Egg-laying
commences soon thereafter. Toads lay their eggs in long strings, while
frogs lay theirs in gelatinous masses. Only the American toad, spring
peeper, and the gray treefrog occur at high altitudes in the park, and
these are uncommon there.
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