Seven species no longer with us
are vanishing in several major hot spots, including western North America,
Puerto Rico, Central America, the high Andes, and northeast Australia.
Five of the seven frogs shown below once lived in these areas. For these
frogs its probably too late. Extinction is forever.
by Rachel Ivanyi
© National Geographic Society
Valley leopard frog (Rana
Description: Olive green above with honey yellow hind limbs, this
leopard frog had pale stripes on the folds between its back and sides.
Its legs were short and stocky.
Distribution: Las Vegas Valley, Clark County, Nevada.
Habitat: This medium-size (two to three inches from nose to rear)
leopard frog lived in seeps, springs, creeks, and the adjacent narrow
corridor of riparian habitat (cottonwoods, willows, and tules) at an elevation
of about 2,000 feet.
Diet: Probably ate insects, spiders, and other invertebrates, as
well as small vertebrates, including fish and their own young.
Reproduction: Vegas Valley leopard frogs may have bred in springs
and streams where the adults lived much of the year, as water temperatures
permitted. Young frogs appeared from April through August.
Status: Last seen in the wild in 1942.
Loss of habitat (springs were capped and
groundwater was pumped to supply a growing Las Vegas with water)
Introduced aquatic predators (bullfrogs
painted frog (Discoglossus nigriventer)
Description: Ocher, rust, gray, and black made up the painted frogs
colorful back. Small white spots dappled its dark belly.
Distribution: Northern Israel and possibly adjacent parts of Syria.
Status: Last seen in the wild in 1955.
Loss of habitat (draining wetlands for farmland)
mist frog (Litoria nyakalensis)
Description: Olive-brown or gray-brown above and cream below, this
medium-size (up to two inches from nose to rear), smooth-skinned frog
had fully webbed toes with large discs on its toes, a characteristic of
climbing tree frogs.
Distribution: Coastal ranges and scarps of the Cairns region, northeastern
Habitat: Fast-flowing streams in upland rain forests.
Reproduction: Mountain mist frogs usually perched on rocks or low
vegetation hanging over fast-flowing streams. During breeding season (October
to March), males repeatedly emitted a soft, slow, popping growl to call
mates. The females laid eggs under rocks in riffles. The pale brown tadpoles
had large mouths with suction lips that enabled them to cling to rocks
in swift water.
Status: Last seen in the wild in 1990.
Possible culprits: Unknown
frog (Rheobatrachus silus)
Description: Brown to almost black on top and whitish underneath,
this medium-size (up to two inches from nose to rear) frog had a blunt
snout and slender, fully webbed toes.
Distribution: Blackall and Cannondale Ranges of southeastern Queensland,
Rocky mountain streams and pools in rain forest and tall, open forest
with an understory.
Diet: These nocturnal stream dwellers hid under rocks during the
day and on top of rocks or partly submerged at night. They fed on small
Reproduction: Gastric-brooding frogs mated between October and
December, depending on on the summer rains. The male emitted a loud staccato
call. The female swallowed the fertilized eggs or young tadpoles and nurtured
up to 25 offspring in her stomach. Hormones produced by the young shut
down the females digestive process, and she didnt eat during
the gestation period. Six to seven weeks later she opened her mouth, and
tiny, fully formed frogs hopped out. Scientists had hoped that studies
of the gastric brooders ability to shut down enzyme production in
the stomach would benefit people with gastric ulcers.
Status: Last seen in the wild in 1981.
Possible culprits: Unknown
toad (Bufo periglenes)
Description: True to its name, the male golden toad was a flaming
golden orange. The larger (about two inches from nose to rear) female,
ranging in color from dark olive to black, was dappled with bright red
splotches edged in yellow.
Distribution: Monteverde Cloud Forest Preserve, Costa Rica.
Habitat: Undisturbed elfin cloud forest at elevations from 6,500
feet to 6,900 feet.
Diet: Little is known about the feeding habits of these secretive
frogs, which hid underground except during the short breeding season.
Because of their small size, golden toads probably fed on small invertebrates.
Reproduction: Golden toads gathered at shallow pools that formed
during the spring rainy season. Males outnumbered females by as much as
eight to one, so males mated with almost anything that moved, including
other pairs locked together in the mating embrace. Four to ten males sometimes
clung to each other, forming whats called a toad ball. Females laid
a string of 200 to 400 eggs; it took five weeks for the tadpoles to develop
into tiny toads.
Status: Last seen in the wild in 1989.
Climate change (prolonged drought, increase
Pollution (long-distance pesticides,
toxins, and pollutants)
coqui (Eleutherodactylus jasperi)
Description: The golden coquis skin color, which ranged from
olive-gold to pale yellow, had a translucent golden cast that gave it
its common name. The transparent skin on the abdomen of this small (less
than an inch from nose to rear), smooth-skinned frog revealed the heart,
abdominal lining, and gonads.
Distribution: South of Cayey, Puerto Rico, at elevations between
2,300 feet and 2,800 feet.
Habitat: Golden coquis lived in the axils of bromeliads (tropical
plants in the same family as pineapples and Spanish moss) that grew less
than three feet apart. Two or more adults and two or more juveniles occupied
each bromeliad. The adults were territorial, defending their axil from
other frogs by shoving and biting.
Diet: Golden coquis probably fed on insects and other tiny invertebrates,
especially those drinking the water trapped in the bromeliad.
Reproduction: The golden coqui was the only New World frog known
to produce live young instead of laying eggs. The female was probably
fertilized internally and incubated three to six eggs in a modified oviduct
for about 28 days. At birth the young resembled the adults and stayed
with their parents for an undetermined period.
Status: Last seen in the wild in 1981.
Pollution (acid rain)
Low reproductive rate
Grande harlequin frog (Atelopus cruciger)
Description: Cruciger, the scientific name of this slender
harlequin frog, comes from the Latin word crux, or cross, referring
to the dark cross on its head, shoulders, and back. Its poisonous skin
ranged in color from yellowish green to olive. As with many other frog
species, males were smaller (1-1.5 inches from nose to rear) than females
(1.5-2 inches) and emitted three types of calls.
Distribution: Coastal mountains of northern Venezuela, from the
lowlands up to cloud forest.
Habitat: Moist rain forests.
Diet: By day these slow-moving frogs sat along streams, probably
feeding on ants, termites, beetles, and other small invertebrates. They
spent the night hidden in low vegetation. These harlequin frogs had only
one known enemya nonvenomous snake immune to the neurotoxins in
the frogs skin.
Reproduction: Harlequins gathered to mate in the dry season, when
there was less chance their eggs and tadpoles would be washed away. Males
probably attracted females by calling and with visual displays, such as
stamping and hopping. Males stayed with the females up to 19 days. Females
laid as many as 270 eggs, which hatched in about three days. Suckers extending
from the tadpoles mouths enabled them to cling to stream bottoms
so they wouldnt be swept away.
Status: Last seen in the wild in 1982. The Rancho Grande harlequin
frog was once so abundant that in certain seasons scientists could collect
hundreds in just one hour.
Climate change (drought)