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Reptiles and Amphibiansof the Americas
2
Dyeing Poison Dart Frog
Source: 1- https://animaldiversity.org/accounts/Dendrobates_tinctorius/,
2- https://philadelphiazoo.org/Animals/Amphibians/Frogs-Toads/Dyeing-Poison-Dart-
Frog.aspx, 3- http://www.zoonewengland.org/stone-zoo/our-animals/reptiles-
amphibians/dyeing-poison-dart-frog
Description:
This is a large poison frog, commonly 1.6 to 2.0 inches with some females reaching 2.4 inches.
They are bright blue frogs with two broad yellow stripes on the back. These stripes are
connected by cross bands to produce two to three oval blue islands down the middle of the
back. The arms and legs are black or deep blue with many bright yellow or black spots.
Sometimes the yellow is replaced with white or the two yellow stripes fuse across the back to
produce a frog with a solid yellow back on a bright blue or black background--they are truly
striking animals. It has a typical erect posture and a distinct tympanum (eardrum) about half
the diameter of the eye. In theory males can be distinguished from females by having larger
finger discs that are cut straighter across the tips. Additionally, males are somewhat territorial
and may wrestle, but so do females on occasion. Only males will call.
Range:
They inhabit small isolated pockets in French Guinea and northeastern Brazil. They prefer
humid, wet habitats and their skin is not waxy enough to prevent evaporation in dry air. Often
they are found in heavy vines, three to six feet above the ground where their bright yellow
stripes stand out in the darkness of the forest.
3
Dyeing Poison Dart Frog (cont.)
Diet:
Their diet consists mainly of ants, termites and other small insects and small spiders. Adults
tend to actively search and hunt down prey.
Life History:
Their bright colors are warnings to other animals of their skin toxins and that they are not fit to
eat (aposematic). The poison allows them to be diurnal unlike most other frogs that are
nocturnal.
Amplexus (the mating position of frogs and toads, in which the male clasps the female about
the back) occurs always on land with this frog, never in water. Eight to ten eggs are laid and the
male sheds the sperm directly over the eggs. When the tadpoles develop in the eggs, the male
will carry them on his back to water. Dozens of tadpoles may be placed in one large water hole
by several males. Tadpoles reach transformation size in about ten weeks and feed on almost
anything small living in the water.
Conservation:
These frogs are isolated because of the unusual nature of region’s forests, with relatively dry
savannahs and high mountain plateaus; no two populations that are exactly alike. One or two
cases of over collecting could wipe out a separated population. Logging destroys and fragments
habitats. They are currently listed as a species of least concern.
Fun Facts:
The common name dyeing poison dart frog comes from a legend that native people used the
skin of this frog to dye the parrot feathers used in their rituals.
The frogs’ toxicity comes from the ants or other insects they eat in the wild. Captive-bred
poison dart frogs are not toxic due to their different diet.
4
Giant Waxy Monkey Frog
Source: 1- http://eol.org/pages/1048381/details,
2- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4582952/
Description:
Males 3.6 to 4.0 inches, females 4.4 to 4.7 inches. The dorsum (back) is dark green and the belly
varies from white to yellow-white or cream. There are sparse white spots with dark frames on
the lower lips, chest and front legs and these are denser on the flanks and hind legs. Fingers are
transparent brown with large green adhesive discs. A prominent gland extends from behind the
eye over the tympanum. The iris is dark gray.
Range:
This species is found in the Amazon Basin in Venezuela, Brazil, Colombia, Peru, Bolivia and the
Guianas.
Diet:
They eat small insects.
Life History:
The species is arboreal and nocturnal. Males usually call from high trees, and descend with the
female to construct nests three to nine feet above ponds. Reproduction occurs throughout the
year in ponds near to, or far from, streams, with a peak from November to May (rainy season).
The females deposit about 600 unpigmented eggs in a gelatinous mass in leaf nests hanging
over ponds. The leaves are joined or folded with the aid of the male. After 8 to 10 days, the
tadpoles hatch and fall into the water, where they complete their development.
5
Giant Waxy Monkey Frog (cont.)
Conservation:
They are a species of least concern. There are very few threats through its wide range, though it
is probably impacted locally by very severe habitat loss, such as clear-cutting. It might benefit
from road cuts through forest where individuals congregate to reproduce. There is currently an
increased interest in the toxic compounds in the skin of this frog (which is used for hunting
practices for several tribes of Amazonia). This might increase harvesting effort in the future, but
at the moment, such utilization is not considered to constitute a threat to the species. It is
sometimes found in the international pet trade but at levels that do not currently constitute a
major threat.
Fun Fact:
Shaman use excretions from these frogs in hunting rituals because they supposedly bring good
luck.
6
Golfodulcean Poison Dart Frog
Source: 1- https://amphibiaweb.org/cgi/amphib_query?where-genus=Phyllobates&where-
species=vittatus, 2- https://www.elmwoodparkzoo.org/animal/golfodulce-poison-dart-frog/
Description:
Golfodulcean poison dart frogs measure just 1.0 to 1.4 inches. Their back and head are solid black with orange or yellow stripes that run from either side of the snout, over their back and to the thigh. The dorsal (back) surface and limbs are generally blue-green with black speckling.
The tadpole coloration is uniformly dark brown on the dorsal side of the body, tail and fins, with the venter (underside) being a lighter brown. Tadpoles develop the paired bright-orange stripes characteristic of the adults about two months after hatching, near the time of metamorphosis. Larvae reach 1.2 inches in total length.
Range:
The Golfodulcean Poison-Dart Frog is endemic to Costa Rica, inhabiting the wet forests and
lowlands of the Golfo Dulce region in the southwestern part of Costa Rica. It has also been
reported to occur near Dominical, in the province of Puntarenas, Costa Rica. This species is
found between 65 to 1800 feet in elevation. It prefers the leaf litter of forested valleys with
streams.
Diet:
They feed on small insects including ants, termites, flies, beetles and mites. Their estimated
daily intake is approximately 75 insects per day.
7
Golfodulcean Poison Dart Frog (cont.)
Life History:
They are a diurnal, terrestrial species. This species is reasonably common. They are shy and will hide in rock crevices or holes between tree roots when approached. They move by walking interspersed with rapid hops. Males are thought not to be territorial, but aggressive behavior has been reported in captivity with one frog jumping on the back of the other and pressing down. The advertisement call, which males use to try to attract females to mating sites, consists of a low-pitched, raspy trill lasting two to six seconds. There is also a second type of call, produced during active pair courtship. The courtship call consists of a series of two to five high-pitched chirps dropping successively in pitch, followed by another series after a pause. This call is used when the female is near or pursuing the male.
During the breeding season the female lays clutches every week or two. Each clutch in captivity contains 7 to 21 eggs, usually deposited on leaves above the ground. This species has parental care, with the male parent attending the clutch up to three times a day and engaging in hydric brooding (emptying the bladder on the eggs to keep them moist).
A few days to a week after the eggs hatch (which occurs in thirteen to seventeen days), the male will allow some or all of his tadpoles to crawl up on his back. He then transports from one to thirteen larvae at a time, carrying them for 1 to 2 days, to a water source; in the wild, this consists of a small forest-floor puddle, or water in a fallen palm frond, or a tree-hole. In about forty-five days the larvae metamorphose into small froglets of about 0.5 inches. Froglets are sexually mature at about ten months.
Conservation:
Habitat fragmentation from forest clearing and tree plantations seem to be the major threats.
Water contamination from mining and collection of adults for the pet trade are also reasons for
population decline. They are listed as an endangered species.
Fun Facts:
The scientific name, Phyllobates comes from the two Latin words fyllo (leaf) and bates (walker).
Very true to its name, Golfodulcean frogs often found climbing on trees.
8
Green and Black Poison Dart Frog
Source: 1-
www.dendrobates.org/dendrobatoidea/dendrobatidae/dendrobatinae/dendrobates/dendroba
tes-auratus/, 2- cosleyzoo.org/green-and-black-poison-dart-frog/, 3-
www.rosamondgiffordzoo.org/assets/uploads/animals/pdf/GreenBlackPoisonDartFrog.pdf
Description:
They have many color variants. Most of them are black and either green or light blue with the
black bands or spots. Adults are about 1.6 inches long. Males are a bit smaller and slimmer than
females and have a barely distinct wrinkled vocal sac under the skin of the throat. Poison glands
are located throughout the surface of their body. Their bright colors discourage predators
(those with color vision) from eating them. The boldly contrasting patterns may signal
predators who have no color vision. The skin is slippery and moist.
Range:
They are found on the floor of rainforests in Central America from Nicaragua to Costa Rica.
They prefer locations near small streams or pools.
Diet:
The adults eat spiders, ants, termites, beetles and mites. Tadpoles eat rotifers (a type of
microscopic aquatic animal), protozoans, woody detritus and other tadpoles.
9
Green and Black Poison Dart Frog (cont.)
Life History:
These frogs are mostly terrestrial, though some individuals were observed 165 feet up in trees
while transporting tadpoles to tree holes. Adult frogs are diurnal and active during the whole
day. In the drier habitats of the Pacific, many morphs are inactive during the dry season and
dwell the leaf litter only after rain showers. Both sexes tend to be territorial. Females try to
monopolize strong males and are very aggressive towards female rivals. Depositing of eggs and
the larval development occurs in the leaf litter. Brood care is done in general by males.
Hatching tadpoles are transported separately by the male to small seasonal pools in tree holes,
big leaves, or in small depressions of river rocks. Tadpoles feed mainly on arthropod larvae and
will result to cannibalism if no other food is available.
Conservation:
This species is not currently in danger. However, the destruction of their tropical rainforest
habitat will likely bring them into danger in the future. It is speculated that members of the
family Dendrobates will be the first poison dart frogs to be put on the endangered list as the
pet trade is lowering their numbers in the wild.
Fun Facts:
This species was also introduced in Hawaii and has flourished there and are a metallic green or
brownish-black. There are at least 13 different color morphs of this frog.
10
Mountain Chicken Frogs
Source: 1- http://www.arkive.org/mountain-chicken/leptodactylus-fallax/
Description:
One of the world’s most threatened frogs, the oddly-named mountain chicken is so called because its meat is said to taste like chicken. This curious species is also one of the largest frogs in the world, with adult females growing up to remarkable lengths of 8.3 inches. The mountain chicken is highly variable in color, with the upper parts varying from a uniform chestnut-brown to being barred or even spotted. The color becomes more orange-yellow on the sides of the body, and pale yellow on the underparts. A black line runs from the snout to the angle of the mouth, and the upper legs often have broad banding. The mountain chicken also has a distinctive, dark-outlined fold from the back of the head to the groin, and large, conspicuous eyes with dark pupils and a golden iris. The body of the mountain chicken is robust, with a large head and well-muscled legs. The male mountain chicken may be distinguished from the female by its smaller size, and by the black ‘spur’ on each of its thumbs, which are used to clasp the female during amplexus (the mating embrace).
Range:
The mountain chicken was once found on many of the eastern Caribbean islands but is now restricted to just Dominica and Montserrat. It once occurred on Guadeloupe, Martinique, Saint Kitts and Nevis, but is now extinct on these islands, and it may have inhabited Saint Lucia and Antigua. The species was also unsuccessfully reintroduced to Jamaica and Puerto Rico.
11
Mountain Chicken Frogs (cont.)
Today, the mountain chicken is largely restricted to the western side of Dominica and the Centre Hills of northern Montserrat, having been lost from much of the rest of the island due to recent volcanic eruptions. It is also found on the eastern side of Dominica, but the species’ origin there is unclear and it may have been introduced to the area.
Diet:
Its diet is highly varied, but it is thought to be strictly carnivorous, largely consuming crickets, although it also eats millipedes, insects, crustaceans and even small vertebrates, such as other frogs, snakes and small mammals.
Life History:
A sit-and-wait predator with a voracious appetite, the gluttonous mountain chicken consumes almost anything that can be swallowed whole. It is well camouflaged against its habitat and remains still for long periods of time before ambushing its prey, usually at night. During the day the mountain chicken resides in burrows which it digs into moist soil. The mountain chicken has a highly unusual method of reproduction, as unlike most other amphibians which breed in water, this frog breeds in underground burrows around 20.0 inches deep. The breeding season starts towards the end of the dry season, usually in April when there are heavy seasonal showers, and continues to August or September. At the start of the breeding period, the male frogs compete to gain access to preferred nesting sites by wrestling and making loud ‘whooping’ calls from forest paths and undergrowth clearings. The winning male occupies a nesting burrow and emits ‘trilling barks’ to attract a female mate. Once a breeding pair is formed, the male and female engage in amplexus, and the female is stimulated to release a fluid, which the male makes into a foam with rapid paddles of his hind legs. Once the nest is built, which takes 9 to 14 hours, the male leaves the burrow to defend it from intruders, while the female lays the eggs. After the larvae have hatched, the female mountain chicken lays up to as many as 25,000 unfertilized eggs upon which the larvae feed. The young froglets take around 45 days to develop, and during this time the female continuously renews the foam, only leaving the nest to feed. Eventually 26 to 43 froglets emerge from the nest, with the timing of this coinciding with the onset of the wet season, when there is an abundance of food. The mountain chicken reaches maturity at around 3 years, and has a lifespan of approximately 12 years. Mature females only produce one brood per season, but male frogs may father the offspring of more than one female.
12
Mountain Chicken Frogs (cont.)
Conservation:
An unfortunate victim of hunting, disease, natural disasters and habitat loss, the mountain chicken population has recently undergone catastrophic declines, estimated at around 80 percent since 1995. On Dominica, this Critically Endangered frog is favored for its meaty legs, which are cooked in traditional West Indian dishes, and which are in fact the country’s national dish. Annual harvests were thought to be taking between 8,000 and 36,000 animals before a ban on hunting was introduced and, as a result of this exploitation, the population on the island is thought to be near extinction. Perhaps the greatest, and least understood, threat to the mountain chicken today is the deadly fungal disease chytridiomycosis. This disease, which has wiped out many amphibian populations across the globe.
Fun Facts:
The mountain chicken is one of the world’s largest living frog species.
Named after the taste of their meat, the mountain chicken lives mainly in the lowlands rather than in the mountains as its name suggests.
The female mountain chicken exhibits a high level of maternal care, producing infertile eggs to feed newly hatched tadpoles.
13
Panamanian Golden Frog
Source: 1- www.detroitzoo.org/animals/zoo-animals/panamanian-golden-frog/, 2-
www.arkive.org/panamanian-golden-frog/atelopus-zeteki/, 3-
www.nationalzoo.si.edu/animals/panamanian-golden-frog
Description:
The Panamanian golden frog is a small, brightly colored and toad-like. The head is longer than it
is broad with a pointed, protuberant snout. The body is slim with long limbs, and the upper
surface is smooth with minute spicules (pointed like structures on back). The sexes have similar
coloration, which is usually uniform golden yellow with one to several large black dorsal spots.
Normally, the abdomen is also yellow, but when carrying eggs, the female's ventral surface is a
lighter color. The Panamanian golden frog is the most toxic species of the genus Atelopus, with
the skin of a single individual containing enough toxins to kill 1,200 mice. It’s extremely bright
coloration is adaptive to warning predators.
Adult males measure between 1.3 and 1.9 inches and weigh 0.1 to 0.4 ounces; and females
measure between 1.8 and 2.5 inches and weigh 0.1 to 0.5 ounces. Wet forest males and
females are larger than dry forest frogs.
Range:
This species inhabits streams along the slopes of the central rainforests and cloud forests of
western-central Panama, from 1,100 to 4,300 feet above sea level. Panamanian golden frogs
live in two types of habitats: wet forest streams and dry forest streams.
Diet:
The Panamanian golden frog is predominantly an insectivore. Their diet consists mostly of
insects and other small invertebrates.
14
Panamanian Golden Frog (cont.)
Life History:
Panamanian golden frogs reproduce mainly along streams and other sources of moving water.
Males attract females by visual displays that can include leg and head twitching, stamping the
ground, and hopping in place. It might even appear that this frog “waves” to other golden frogs.
This species developed this behavior as a way of communicating near the fast-moving streams
where audible calls are not as effective. During mating, the female deposits 30 to 75 eggs in
long strings in shallow water as the male fertilizes them.
Tadpoles have a flattened body and an abdominal sucker, which keeps them from being swept
away in the current. Tadpoles are completely white for the first few days after hatching,
developing their color after a few days.
Depending on the individual, they may have black splotches over its bright yellow skin. They
also changes colors while developing, starting off as a blackish-gray tadpole with yellowish
spots. When they emerge on land, they become a stunning green with black markings and later
switches into the well-known golden color.
Conservation:
The beautiful and once locally revered golden frog of Panama may be extinct in the wild as a
result of deforestation, capture by people for the pet trade and amphibian chytrid fungus. The
growing human population in Panama exerts greater pressure on wild ecosystems as areas are
cleared for cattle farming and as the use of chemical fertilizers and insecticides in agriculture
increases. The chytrid fungus infection that is spreading through Central America (and other
parts of the world) is having a devastating effect on this species and many other amphibian
species.
The Panamanian golden frog is protected by law in Panama. While captive breeding programs
in many zoos throughout the United States and at the El Valle Amphibian Conservation Centre
in Panama have been successful, the captive-bred individuals cannot be safely returned to the
wild until chytrid fungus is no longer a concern.
Fun Facts:
The Panamanian golden frog produces a neurotoxin that hurts its predators when attacked.
The frog is considered good luck in Panama and is that country's national animal.
Little definitive information exists on the life span of the Panamanian golden frog but most
estimates put life span between 10 and 15 years.
15
Puerto Rican Crested Toad
Source: 1- https://animaldiversity.org/accounts/Peltophryne_lemur/, 2-
https://detroitzoo.org/animals/zoo-animals/puerto-rican-crested-toad/
Description:
Puerto Rican crested toads are named for the distinct bony crests on their heads. They are
medium-sized toads, from 2.5 to 4.7 inches long from snout to vent; females are larger than
males. The snout is turned up. The basic dorsal coloration is brown to yellow brown with black-
brown blotches; underneath, they are a cream color with dark spots. Juveniles have a chevron
pattern on their backs and have a rust to salmon color on their backs and sides. The skin is
textured, and the eyes are gold with black flecks. Breeding males are olive green and gold,
while females are a darker brown with rougher skin and larger crests. In the breeding season,
males have yellow sides and nuptial pads on their front feet on the first and second digits.
Range:
The Puerto Rican crested toad, is endemic to Puerto Rico and the Virgin Islands. It no longer
occurs on Virgin Gorda and is found today only in one area of Puerto Rico. There were two
populations, one in the North (Quebradillas) and one in the South (Guánica).
Diet:
Puerto Rican crested toads, similar to other toad species, consume a variety of insects and
other small invertebrates of the leaf litter, including ants, beetles, spiders and millipedes. They
are fed small insects in captive breeding programs. Tadpoles eat vegetation, such as algae, and
have been seen to scavenge dead tadpoles and the carcasses of anoles, scorpions, and
millipedes.
16
Puerto Rican Crested Toad (cont.)
Life History:
Eggs are deposited in water and hatch into free-swimming larvae (tadpoles) in about 24 hours.
Metamorphosis to the terrestrial form takes 14 to 21 days or longer due to temperature, food
availability, and other variables.
Puerto Rican crested toads are thought to breed once annually. Some individuals may breed
biannually, but more research is needed on this point. When it rains, males go to temporary
ponds and call. When there is 7 inches of rain or more, toads from 0.6 to 1.2 miles away move
to the breeding pond; when there is 7 to 13 inches, breeding populations come from 1.9 miles
away. In Guánica, reproduction is intermittent, and is initiated by heavy rain; it appears that at
least 2 inches of rain must fall to stimulate breeding. A decrease in barometric pressure caused
by a hurricane or tropical storm can also cause the toads to move to the temporary breeding
ponds. Breeding has been observed in all months except March, though conditions are most
suitable in the rainy season, particularly April and May, and in the hurricane season occurring
from August to October. Long black strands of up to 150,000 eggs are deposited in aquatic
plants during amplexus. The female leaves the pond, while the male may remain for a few days.
After metamorphosis, toadlets move into forests and upland areas, finding shelter in groups of
15 to 30.
Males call to attract the females to shallow temporary ponds during the breeding season. Thus
they presumably have a good sense of hearing. They also seem to have reasonably good vision,
and undoubtedly good tactile senses, but it is unknown how important each sense is in their
breeding activities.
Conservation:
They are listed as Critically Endangered by the IUCN and Threatened by the USFWS. Numbers
have decreased due to habitat loss and introduced species such as marine ("cane") toads, which
compete for places to lay eggs, food, and shelter and which eat juvenile Puerto Rican crested
toads. Temporary ponds needed for breeding are drained for agriculture and development and
mosquito management. One instance of proposed draining of a pond to allow people to get to
a beach more easily was halted once the population was discovered again in 1984. Natural
disasters such as hurricanes, tidal waves, floods, long periods of drought, increases in salinity,
and rising sea levels, have the potential to eliminate the Guánica population or significantly
decrease its numbers. Breeding in zoos has been done, with tadpoles reintroduced into the
natural habitat. Conservation also involves education, and habitat, restoration and protection,
particularly breeding ponds. Also important is control of predatory and competing species,
assessing potential areas for introduction, and researching basic biology of the toad. The United
States Fish and Wildlife Service (USFWS) created a recovery plan in 1992, and populations have
grown between 1992 and the present.
17
Puerto Rican Crested Toad (cont.)
Fun Facts:
Tiny radio transmitter "backpacks" have been placed on some of these toads by researchers to
track their movements.
The Puerto Rican crested toad was the first amphibian involved in a Species Survival Plan – a
comprehensive management plan through the Association of Zoos & Aquariums that works to
ensure the sustainability of healthy, genetically diverse and demographically varied captive
animal populations.
It only takes 18 days for an egg to grow into a toadlet.
18
Red Eyed Tree Frog
Source: 1- https://animaldiversity.org/accounts/Agalychnis_callidryas/
Description:
Red Eyed Tree Frogs are known foremost for their huge, bright red eyes, a possible adaptation
to nocturnality or the central component of a defensive strategy called startle coloration. Their
dorsal area is usually a neon-like shade of green, but can sometimes range from blue to yellow
in coloring. The sides are light blue with cream to yellow colored stripes. The upper legs are
bright blue, and the feet are a bright orange or red. They have large, specially developed
suction cup toe pads, which allow them to attach to leaves, branches and the sides of trees.
Range:
They can be found throughout most of Central America, as far north as southern Mexico. They
inhabit tropical rainforest areas, where they are commonly found in the lowland rainforests and
surrounding hills, particularly in areas close to rivers.
Diet:
They are carnivorous and feed primarily at night. The red-eyed tree frog's green coloring
permits it to stay hidden among the leaves of trees, waiting for insects or other small animals to
come their way. They eat any type of insect that fits into their mouth, but their usual diet is
composed of crickets, moths, flies, grasshoppers and sometimes even smaller frogs.
19
Red Eyed Tree Frog (cont.)
Life History:
They inhabit tropical rainforest areas, where they are commonly found in the lowland
rainforests and surrounding hills, particularly in areas close to rivers.
They prefer temperatures between 75 to 85 degrees during the day, between 66 to 77 degrees
during the night and humidity at around 80% to 100%.
As reproduction takes place on the underside of leaves, the female must hold on to the
underside of the leaf with her suction-cup toes, holding on for both herself and her mate. Each
group of eggs that a female produces is called a clutch, and the female must enter the water
after laying each clutch, with the male still attached to her back, in order to fill her bladder with
water. If the female does not fill her bladder between clutches, her eggs will dry up and die.
Sometimes when a female and her mate enter the water, other males see them entering and
attempt to force the male from her back. If this is accomplished, another male will take his
position and fertilize the next clutch eggs.
While most frog species lay their eggs directly into the water, the red eyed tree frog lay their
eggs on the underside of leaves that hang over bodies of water. When the clutches of eggs have
developed into tadpoles, which occurs very quickly, the tadpoles swim around within their eggs
until the egg ruptures. The rupturing of all the eggs in the clutch occurs within a one minute
time period, and the fluid released from the ruptured eggs helps to wash all the tadpoles down
the leaf and into the waiting water below. Reproduction is a very strenuous activity for this
frog.
Some believe that the bright, red eyes of this frog act as a form of defense termed startle
coloration. Red-eyed tree frogs are nocturnal and rest during the day. If a predator were to
happen upon this frog they would awaken, and its eyes would pop open abruptly. The sudden
brightness of their red eyes might startle the predator enough to give them the mere seconds
necessary for the agile frog to jump to safety.
The musical mating ritual of this frog begins by the loud croaking of one red-eyed tree frog,
who is quickly joined by the other male in the area, all sharing the common goal of attracting
females. This loud croaking continues as males jump from one leaf to another in a crazed
attempt to establish territory. Male frogs are also known to "quiver" to attract females, but this
act has only been seen by a few people. Quivering occurs when the loud croaking is at its
climax. Male frogs inflate their vocal cavities and rise on all fours in an attempt to attract
females and deter other males from entering their territory. During this process, at least two
males face each other and quiver, their bodies violently shaking. This quivering ritual
establishes territory and demonstrates strength and intimidation. During this process, when
sparked by even the smallest movement, males wrestle with other males, and sometimes many
males climb on top of one another. There have even been cases where one frog pinned another
20
Red Eyed Tree Frog (cont.)
down on a leaf. This quivering process has only been observed in the genus Agalychnis.
Sometime during this mating ritual, trying not to attract too much attention, the females slowly
come down from the treetops. Once the female has been noticed, many different males will
jump on her back, fighting each other for the best positioning. The best positioned male is the
one who is straight on her back and can clamp his arms and legs around her stomach.
Sometimes several males will stay on her back for days until she finds an adequate spot to lay
her eggs. Once she is in this spot, all the males attempt to fertilize her eggs.
Conservation:
These frogs are not considered threatened in their natural environment. However there has
been much concern about the overall condition of the rainforest habitat in which these frogs
reside. Global warming, deforestation, climatic and atmospheric changes, wetland drainage,
and pollution have caused dramatic declines in the amphibian population in, and among the
rainforests of Central and South America.
Fun Facts:
By day, red-eyed tree frogs will conceal their brightly colored flanks with their limbs and close
their eyes to sleep. This posture helps camouflage them against leaves and also reduce water
loss
Red-eyed tree frogs are not poisonous
21
Yellow Banded Poison Dart Frog
Source: 1- https://animaldiversity.org/accounts/Dendrobates_leucomelas/, 2-
http://www.rosamondgiffordzoo.org/assets/uploads/animals/pdf/Yellow-
bandedPoisonDartFrog.pdf,
Description:
They are one of the largest species in the genus Dendrobates, with an adult body (snout to
vent) length ranging from 1.2 to 2.0 inches, although individuals are only rarely more than 1.5
inches. Average weights of 0.1 ounces are reported.
This species is defined by its distinctive yellow and black bands across the body. As an individual
frog ages, the black bands often break off into spots. This bright coloration undoubtedly
represents aposematic coloration, which is defined as having conspicuously bright colors that
are used as a warning of danger or distastefulness to potential predators. These frogs are
known to produce toxic chemicals in their skin, making them poisonous to most would-be
predators. Females of this species are often larger and more robust than the males.
Range:
Yellow banded poison dart frogs, are found in the Neotropical region, in northern South
America. The range includes Venezuela, northern Brazil, Guyana and southeastern Colombia.
Yellow-banded poison dart frogs prefer humid or wet habitats and can be found on forest soil in
moist stones, wet tree trunks and roots of rainforest trees. Tadpoles can be found in epiphytic
(a plants that grows on the surface of another plant and derives its moisture and nutrients from
the air, rain and water) plants such as bromeliads. They are found in lowland regions with
average temperatures of 79 to 86 degrees Fahrenheit or above. These frogs have been reported
at elevations of 164 to 2,624 feet above sea level.
22
Yellow Banded Poison Dart Frog (cont.)
Diet:
Largely insectivorous, the diet of these frogs consists of ants, termites, tiny beetles, crickets and
other small insects and spiders.
Young are sometimes cannibalistic, although this behavior is apparently limited to times when
unwary adults place new tadpoles into an already occupied pool.
Life History:
They are diurnal. Frogs live mainly on the ground, but also climb into trees. These frogs have
glandular adhesive pads on their toes and fingertips, which help them to adhere to plant
surfaces. This allows these frogs to climb and cling.
Males are very territorial and can be aggressive in defense of a calling/breeding territory. Males
call from their oviposition sites to attract females. Other frog species are ignored or avoided.
Territorial disputes can lead to aggressive behavior that can include grasping belly-to-belly and
emitting a sporadic buzzing call. When not breeding, these animals are a solitary. The size of the
territory is unknown.
Males use vocalizations such as chirps, buzzes, trills and hums to attract females. Direct
behavioral actions facilitate courtship and stimulate oviposition. Call sounds like pleasant
"birdlike" trills, lasting for 10 to 15 seconds.
In addition to vocalizations, males use visual cues as well to show off their brightly colored
bodies. Tactile communication is important in breeding, as females and males touch one
another in courtship.
Tadpoles use vibrations through water to signal their presence in a water pool to adult frogs.
Should a male deposit a second tadpole into a pool, the first tadpole is likely to eat it.
These frogs depend upon vision to locate prey. In general frogs are not known to have a strong
sense of smell, so it is unlikely that they use chemical communication.
Conservation:
They are listed as a species of least concern.
Fun Facts:
The yellow-banded poison dart frog is the only known poison frog to estivate (be dormant or
inactive) during the dry season
23
Salamanders and Newts
Axolotl
Source: 1- https://animaldiversity.org/accounts/Ambystoma_mexicanum/
Description:
Axolotls are paedomorphic or neotenic aquatic salamanders, meaning they retain certain larval
characteristics in the adult, reproductive state. They possess feathery external gills and finned
tails for swimming. They have dark, mottled brownish-green skin. Axolotls reach lengths on
average of 9 inches, but can grow to more than 12 inches in length.
The sexes can be easily distinguished in adult axolotls. Males can be identified by their enlarged
cloaca, while females have a smaller cloaca and round, plump bodies.
Range:
Axolotls are historically found in Lakes Chalco and Xochimilco of the Valley of Mexico near
Mexico City, Mexico.
Diet:
Generally the top predator in their natural environment, axolotls will eat anything that they can
catch, including mollusks, fishes, and arthropods, as well as conspecifics (a member of the same
species).
24
Axolotl (cont.)
Life History:
They are paedomorphic, which means they retain larval characteristics in the reproductively
mature adult form. Juvenile and adult axolotls possess feathery, external gills and tail fins suited
to an aquatic lifestyle.
Their courtship behavior first involves each animal nudging the other's cloacal region,
eventually leading to a "waltz," with both animals moving in a circle. Next, the male moves
away while undulating the posterior part of his body and tail (resembling a "hula dance"), and
the female follows. The male will deposit a spermatophore (a cone-shaped jelly mass with a
sperm cap) by vigorously shaking his tail for about half a minute, and will then move forward
one body length. The female then moves over the spermatophore, also shaking her tail, and
picks up the spermatophore with her cloaca.
Axolotls breed in the wild generally from March to June. From 100 to 300 eggs are deposited in
the water and attached to substrates. Eggs hatch at 10 to 14 days and the young are
immediately independent. Sexual maturity is reached in the next breeding season.
Eggs are surrounded by a protective jelly coat and are laid singly, unlike frog eggs (which are
laid in clumped masses), because they possess higher oxygen requirements. They are often
attached to substrates such as rocks or floating vegetation.
Axolotls communicate mainly via visual cues and chemical cues during mating. At other times of
the year there is little to no intraspecific communication.
Conservation:
Their habitat is nearly gone. Historically, they have been known to live in high altitude lakes
near Mexico City. Lake Chalco is gone completely, drained for drinking water, and Lake
Xochimilco is now nothing more than a scattering of canals and swamps. Because known
populations are few and far between, very little is known about the ecology and natural history.
Fun Facts:
The word "axolotl" comes from the native Aztec language, or Nahuatl. It roughly translates to:
water servant, water sprite, water player, water monstrosity, water twin or water dog.
25
Dwarf Siren
Source: 1- https://srelherp.uga.edu/salamanders/psestr.htm, 2-
https://www.inaturalist.org/taxa/27868-Pseudobranchus-axanthus, 3-
https://amphibiaweb.org/species/4313
Description:
The Dwarf Siren is the smallest of the three sirens found in Florida, ranging from 4 to 6 inches.
The Dwarf Siren has external gills, three toes on its front legs, and lacks hind limbs. The head is
triangular and delicate, the tail is laterally compressed, and the body is slender. Five subspecies
occur over its range and vary in distribution and color patterns, but most have at least faint
stripes along the sides.
Range:
The Dwarf Siren is found throughout Florida and in the Coastal Plain of southern Georgia and
South Carolina. This species is often found near the aquatic plant, water hyacinth in the
shallow, weedy water of ponds, swamps and ditches. Due to its association with the plant, the
dwarf siren’s range may be extending northward.
Diet:
The siren feeds on tiny invertebrates they find along the bottom of the body of water they live
in. Dwarf sirens have surprisingly small mouths, but will likely eat any invertebrate they can
swallow.
26
Dwarf Siren (cont.)
Life History:
The dwarf siren is totally aquatic, nocturnal, and their behavior could be described as being
sluggish as they move slowly. Not much is known about the reproductive tendencies of this
species other than the fact that eggs are laid one at a time in spring attached to aquatic
vegetation and hatch in approximately one month. Eggs average 0.1 inches diameter and have
three jelly envelopes. It is assumed that fertilization is external. The siren is able survive periods
of drought by burrowing into the muddy substrate and forming a cocoon of mucus and shed
skin. Because of its secretive habits, little is known about the ecology of this species.
Conservation:
It is not threatened, but many local populations undoubtedly have been eliminated by the
destruction of wetlands, especially due to urbanization (commercial, residential and tourism
expansion, including transportation corridors).
Fun Facts:
They may produce high-pitched squeaks when threatened.
27
Hellbender
Source: 1- https://www.nwf.org/Educational-Resources/Wildlife-Guide/Amphibians/Hellbender
Description:
The hellbender—sometimes called a “snot otter” - is a large, fully-aquatic salamander with a flat head, wrinkled body, and paddle-shaped tail. Their body is usually dark gray or brown with irregular dark spots along the back. Although sometimes confused with mudpuppies, hellbenders are easily distinguished by their lack of external gills. Reaching four to 5 pounds, the hellbender is the largest salamander in North America by weight. Adults average 20 inches in length, but can grow up to 29 inches.
Range:
Two subspecies of hellbenders exist in the United States. The Ozark hellbender (Cryptobranchus alleganiensis bishopi) lives in a small number of rivers in Missouri and Arkansas. The eastern hellbender (Cryptobranchus alleganiensis alleganiensis) is broadly distributed throughout the Appalachian region (southern New York to northern Georgia) and also occurs in Kentucky, Ohio, Indiana, Illinois, and Missouri. Hellbenders typically live under large rocks or boulders that are partially buried in cold, fast-flowing streams. These rocks provide protection from predators, and hellbenders may abandon a habitat if the rocks are removed or disturbed. Juvenile hellbenders have many predators, including fish, turtles, water snakes and other hellbenders. Adults have few predators, but may be eaten by raccoons, minks, and river otters.
Diet:
Hellbenders eat primarily crayfish and fish, but have been known to occasionally eat insects, tadpoles and even other hellbenders (including eggs). With its large, gaping mouth, the hellbender can eat an animal that is almost as big as itself.
28
Hellbender (cont.)
Life History:
Hellbenders mate in the fall, under large “nest” rocks. Females lay a double strand of 100 to 500 eggs, which are fertilized externally. Males guard the nests, and eggs hatch in about two months. Larvae are about an inch long and have external gills. When hellbenders are about two years old, the gills disappear and they start breathing entirely through their skin. Hellbenders reach sexual maturity at around six to eight years of age. The hellbender’s lifespan in uncertain. Captive individuals have lived up to 29 years, but one study suggests hellbenders may live 50 years or more in the wild.
Conservation:
Hellbender populations have declined throughout most of the species’ historic range. The Ozark hellbender is federally endangered, and the conservation status of the eastern subspecies is currently being evaluated by the U.S. Fish & Wildlife Service.
Fun Fact:
Hellbenders have large, simple lungs that are used for buoyancy instead of breathing.
29
Caecilians
Aquatic Caecilian
Source: 1- http://www.jacksonvillezoo.org/listingDetails.aspx?listingID=7004&pageID=15577
Description:
Aquatic Caecilians grow to 17.7 to 21.7 inches in length. They are dark grey- black in color. The
most distinguishing characteristic of all caecilians is their limbless, worm-like bodies. They can
breathe air at the surface of water or soil but most of the respiration takes place through their
skin. The species is ovoviviparous, giving birth to young in water. The gestation period lasts
approximately 220 days. Three to seven live, fully developed young are born, which after only
one year grow to almost half the size of an adult at just under 10 inches.
Range:
The drainage systems of the Cauca and Magdalena rivers in western and northern Colombia to
the general vicinity of Lake Maracaibo Basin in Venezuela. They occur up to 3,280 ft above sea
level.
Diet:
In the wild, caecilians eat worms, caterpillars, termites and small burrowing snakes.
Life History:
Caecilian behavior is not well known. They are not a well-studied order due to difficulty of
finding them in their well-hidden burrows. They are thought to be solitary, coming together
only to mate. The young are also thought to be rather precocial (an advanced state and able to
feed themselves almost immediately) when born, with the mother not caring for them after
30
Aquatic Caecilian (cont.)
birth. They stay underground until heavy rains drive them to the surface, presumably to avoid
drowning. Inside the skin are fish-like calcite scales.
The skin also has numerous ring-shaped folds, or annuli, that partially encircle the body, giving
them a segmented appearance. Like other living amphibians, the skin contains glands that
secrete a toxin to discourage predators.
Caecilian anatomy is highly adapted for a burrowing lifestyle. They have a strong skull, with a
pointed snout used to force their way through soil or mud. In most species, the number of
bones in the skull are reduced and fused together, and the mouth is recessed under the head.
Their muscles are adapted to pushing their way through the ground, with the skeleton and
deep muscles acting as a piston inside the skin and outer muscles. This allows the animal to
anchor its hind end in position, and force the head forwards, and then pull the rest of the body
up to reach it in waves. In water or very loose mud, caecilians instead swim in an eel-like
fashion.
Caecilians in the family Typhlonectidae are aquatic and are the largest of their kind. The
representatives of this family have a fleshy fin running along the rear section of their body,
which enhanced propulsion in water. Most caecilians have two sets of muscles for closing their
jaws, compared with the single found in most other vertebrates. Adaptations to their
underground life include having eyes that are small and covered by skin for protection. This has
led to the misconception that they are blind. This is not strictly true, although their sight is
limited to simple dark-light perception. All caecilians possess a pair of tentacles, located
between their eyes and nostrils. These are probably used for a second olfactory capability. All
caecilians have lungs, but also use the skin or the mouth for oxygen absorption. Often the left
lung is much smaller than the right one, an adaptation to body shape that is also found in
snakes. The eggs are guarded by the female. For some species the young caecilians are already
metamorphosed when they hatch; others hatch as larvae. The larvae are not fully aquatic, but
spend the daytime in the soil near the water.
Conservation:
IUCN listed as Least Concern in view of their wide distribution, tolerance of significant habitat
degradation, and their presumed large population. They are popular in the international pet
trade, but not at a level to constitute a threat to the species.
Fun Facts:
These unique animals were burrowing underground long before the dinosaurs even appeared!
They are nearly blind and find their food by taste and smell.
31
Reptiles
Crocodilians
Dwarf Caiman
Source: 1- https://www.arkive.org/dwarf-caiman/paleosuchus-palpebrosus/, 2-
https://philadelphiazoo.org/Animals/Reptiles/Crocodiles-Alligators/Dwarf-Caiman.aspx
Description:
The male typically reaches a maximum of 5.25 feet, while the female rarely exceeds 4 feet. This
predator has bony upper eyelids and has a heavy armor on their back composed of scales
containing bone-like material (osteoderms). The tail of the dwarf caiman contain the largest
amount of osteoderms on their body, meaning that the tail is brittle and inflexible and the tail
tip can break relatively easily. The snout of the dwarf caiman is short and broad. Unusually, the
iris surrounding the pupil of the eye is completely dark.
The juvenile dwarf caiman is mostly brown with a black banded pattern. As it matures, the
juvenile develops the darker coloration and chocolate brown head of the adult, as well as a
white banded pattern on their lower jaw.
Range:
The dwarf caiman is widespread in South America. They are found in numerous aquatic habitats
throughout their range. In the central Amazon basin, this species can be found in the flooded
forests that surround the major waterways. In other areas of their range, the dwarf caiman has
been seen living in swamps, lagoons, calm areas of large rivers and around rapids.
32
Dwarf Caiman (cont.)
Diet:
Dwarf caiman juveniles are found to eat mainly invertebrates such as crustaceans, while the
diet of an adult is more varied and includes fish, crabs and shrimp.
Life History:
They conceal themselves during the day in burrows below water level which can be up to 5 feet
long. This species leaves the water only rarely.
Very few investigations into the reproduction of the dwarf caiman have been conducted,
therefore little information is currently known. This species can be found in pairs and alone
throughout the year and no set breeding season has yet been described. The female builds the
nest in a concealed location, using leaf debris and mud to create a small mound. Clutch sizes
vary between 15 and 25 eggs, and the female guards the nest during the 90
day incubation period. Despite a lack of research into post-hatching care by the adults, they
have been noted that, particularly during the dry season, hatchlings and females will remain
together in a burrow. The juveniles will generally remain with the adults until they are around
21 months of age.
Conservation:
According to the IUCN the dwarf caiman is a species of least concern.
Fun Facts:
The dwarf caiman is the smallest of the New World crocodilians.
While most crocodilians have yellow eyes, this species has brown eyes.
33
Turtles
Amazon River Turtle
Source: 1- https://nationalzoo.si.edu/animals/yellow-spotted-amazon-river-turtle, 2-
https://www.akronzoo.org/yellow-spotted-amazon-river-turtles, 3-
https://www.arkive.org/yellow-headed-sideneck-turtle/podocnemis-unifilis/
Description:
They have a domed and dark colored shell. They have yellowish-orange head markings. There is
usually a single barbel on the chin. These side-necked turtles cannot retract their head into
their shell. Hatchlings have very obvious yellow spots on their heads, which shrink as they grow.
Males keep some of the yellow spotting; females lose their spots altogether.
The average adult length is 15 to 27 inches, with females outgrowing males. Adult males weigh
1 to 2 pounds and females weigh 2.5 to 6.5 pounds.
Range:
They are found in northern South America, mainly in the Amazon and Orinoco River drainages,
large rivers, backwaters, lagoons and flooded forests. During the flood season, they avoid fast
moving waters by taking up residence in lakes and flooded forests.
34
Amazon River Turtle (cont.)
Diet:
They are omnivorous, feeding on both vegetation and small animals. They have also been
known to occasionally use an inertial feeding mechanism (sucking prey into their mouth).
Life History:
Mating season varies depending on location, but nesting has been recorded for most months of
the year. The clutch size averages between 15 and 25 eggs but as many as 40 are possible.
A male Amazon river turtle courts a larger female by nipping at her feet and tail. A few weeks
later, in the evening, the female lays about two dozen (20 to 30) hard-shelled, slightly
elongated eggs in a shallow nest she has dug on the riverbank. The nest is about 10 inches deep
and contains 7 to 52 eggs, depending on female body size and incubate under the heat of the
sun for about 2 months. The babies, which are slightly larger than a quarter coin, hatch out in a
little over two months. The sex of the hatchlings is determined by the temperature at which
they incubate. Eggs incubated below 89.6 degrees Fahrenheit will hatch as males, and
those incubated above 89.6 degrees Fahrenheit will be females. Just a few days after hatching,
the young turtles begin to forage for food alone. The Amazon river turtle is diurnal and is most
active in mid-morning and the afternoon. Groups of turtles can be seen basking in the sun, on
logs or stones in the middle of rivers and they may also lie on the shore. As ectothermic (cold-
blooded) animals, this behavior functions to warm their bodies
Conservation:
These turtles are listed as “vulnerable” according to the IUCN Red List. This is due in part to the
large import and sale of these turtles in the 1960’s. The turtles and their eggs are also used for
food in some South American countries. When the females come on shore to lay their eggs, the
turtles and the eggs are collected and eaten.
Fun Facts:
They can live up to 70 years old. They are also known as yellow-headed side-necked turtles.
They do not pull their head and neck directly back into their shell. Instead, they tuck their head
and neck under the edge of their shell to one side, curving it in an “S” shape.
35
Matamata Turtle
Source: 1- https://detroitzoo.org/animals/zoo-animals/mata-mata-turtle/, 2-
https://www.acaquarium.com/animals/matamata-turtle/, 3-
https://nationalzoo.si.edu/animals/matamata-turtle
Description:
The matamata turtle’s carapace is rough and knobby. The head and neck are large, flat and
covered with numerous protuberances, bumps, skin fringes, and ridges resembling fallen leaves
in the water. Unlike most turtles, their jaws are fleshy and not hard. Their snout is used like a
snorkel, minimizing the turtle's movement as only the tip of the snout needs to emerge from
the water for the turtle to breathe.
Range:
Matamata turtles are found throughout the Amazon in northern South America, including
Venezuela, Brazil, Peru, Ecuador, Colombia and Bolivia. They are also found on the island of
Trinidad.
They are primarily aquatic and prefer the soft, muddy bottoms of slow-moving, shallow bodies
of water, such as streams, swamps and marshes. They may also inhabit the brackish waters of
the lower Amazon basin.
36
Matamata Turtle (cont.)
Diet:
Matamatas are carnivorous bottom feeders with a unique predation method that involves
"vacuuming" up small fish and invertebrates. They remain largely motionless and camouflaged
in the muddy waters they inhabit, which allows them to ambush their prey.
Matamatas feed primarily, upon live fish. In addition, they will eat amphibians, invertebrates
(such as insects and crustaceans), small mammals, and birds.
Life History:
Matamatas have extremely poor eyesight, but a number of other sensory aids allow them to
detect movements in the murky substrates they inhabit. Fleshy flaps extend from the sides of
their triangular head, as well as along the neck, which is covered with bumps and ridges. Those
skin flaps help camouflage the turtle and contain nerves that respond to stimuli, such as the
vibrations caused by the nearby movement of potential prey. Tubercles near the corners of the
mouth and neck, as well as barbels on the chin, also have sensory nerves. The turtle's ears are
large and extremely sensitive to sound.
A male begins the courting process by extending their head toward a female and opening and
closing his mouth. He also hyperextends his hind legs and moves the lateral flaps on his head.
Nesting season occurs from October through December. Females build their nests in vegetation
near the edge of a forest. They typically lay 12 to 28 eggs, which have a long incubation period
of about 200 days.
Conservation:
They have no special conservation status. However, with rapid destruction of their native
habitat, this may not hold true in the future.
Fun Facts:
When fish that are attracted by the turtle's fringes of skin swim too close to the head, the
matamata snaps their mouth shut, quickly sucking the fish into the turtle’s mouth; the water is
then slowly expelled, and the fish is swallowed whole.
Despite being an aquatic species, matamatas are not well adapted for swimming in open water.
They are better suited for walking the muddy beds of shallow pools of water, among leaf and
plant debris. Hatchlings and juveniles can swim awkwardly, but adults rarely leave the bottom
of shallow pools and streams.
The Spanish meaning for matamata is “it kills, it kills”.
37
South American Snake-necked Turtle
Source: 1- http://www.eol.org/pages/963539/names, 2-
https://tortoise.org/archives/hydromed.html
Description:
The turtle can reach up to 11 inches in length. Their carapace is strongly keeled, and can also be
distinguished by black and yellowish markings along its head and neck. Generally, the females
are larger than the males, who often have larger tails.
Range:
They live in slow-moving ponds, rivers, streams and marshes (preferably with aquatic
vegetation) of northern Argentina, Uruguay, Paraguay, and southern Brazil
Diet:
They eat snails, aquatic insects, fish and amphibians.
Life History:
In coastal areas, they will enter brackish water, and they may hibernate in colder areas of their
range. Courtship and mating have not been extensively observed in this species and they nest
in spring. The eggs are about an inch long, white, and brittle-shelled. Hatchlings are just over an
inch long and have more wrinkled carapaces than adults.
38
South American Snake-necked Turtle (cont.)
Conservation:
According to the IUCN, their conservation status has not been assessed.
Fun Facts:
They use a method of food capture that is a combination of the vacuum action displayed by the
Matamata and the snake-like striking of other snake-necked turtles (inertial feeding
mechanism).
39
Lizards
Black Iguana
(Male)
(Female)
Source: 1- https://animaldiversity.org/accounts/Ctenosaura_similis/
Description:
Black iguanas are large, bulky lizards with adult males reaching up to 18 inches long with an 18
inch long tail, totally to 36 inches in full. They are predominantly black but the dorsal surface
may show black bands on a greyish background. Most have black mottling on their backs. The
color may also lighten after basking in the sunlight with yellowish and orange markings
becoming evident along the sides. Adult males and females are dimorphic. Adult males have
well developed dorsal crests and small dewlaps. The dewlap, the crescent of skin that can be
extended under the throat, is not inflated. A small bone bows out to extend the dewlap during
times of threat, courtship, or while defending territory. Females lack obvious crests. There is
considerable variation with age and sex and therefore identification may be difficult. The lizards
have tails ringed with rows of sharp, curved spines, hence the name spiny-tailed iguana. The
spines down the back are short. Juveniles tend to be olive-green becoming tan and then finally
greyish as they grow.
40
Black Iguana (cont.) Range:
They are found throughout Mexico, large areas in Central America, and islands adjacent to
Panama. They are great diggers and baskers. They generally live in dry, arid, open terrain.
Diet:
They are generally herbivorous, particularly on legume fruits, but is also known to have a
diverse carnivorous diet that consist of small animals. They will also eat rodents, bats, frogs,
small birds and a variety of insects. They have even been noted to eat eggs of their own young,
and in one case, the tail of a juvenile was found inside an adult male, suggesting cannibalism.
Life History:
This species can be aggressive, and may bite or wound an aggressor with their spines. More
terrestrial than arboreal, they can run in a bipedal fashion. Highly gregarious (groups) and
territorial, these iguanas live in colonies, ruled by a strict pecking order. One male in the colony
is dominant, and although the other males hold territories, they will only defend them against
one another and not against the leader. Larger males usually hold bigger and better territories
and they mate more often. Combat often occurs when iguanas are attaining or defending a
territory or a mate.
Juvenile iguanas often emerge together from the nest-hole, an anti-predator strategy in which
many eyes are better than two and large numbers make individual capture less likely. Young
iguanas often remain in groups with one of them temporarily behaving as a dominant leader.
They engage in mutual tongue-licking and grooming, body and chin rubbing. At night, they
often sleep together on branches.
Conservation:
According to the IUCN they are a species of least concern.
Fun Facts:
Territorial displays involve color changes, body inflation, jaw-gaping, "push-ups" or rapid
nodding of the head, and sometimes, biting and tail thrashing battles.
The young are primarily insectivorous, switching into herbivorous habits as adults.
41
Mexican Beaded Lizard
Source: 1- https://animaldiversity.org/accounts/Heloderma_horridum, 2-
https://www.stlzoo.org/animals/abouttheanimals/reptiles/lizards/mexicanbeadedlizard
Description:
Adult female Mexican beaded lizards grow to about 30 inches in length and weigh 3 to 4.5 lbs.
Males are slightly larger, growing to 35 inches and weighing up to 9 lbs. The tail is the longest
portion of the lizard, nearly 50% of the total length.
Large, hard scales cover the top of the lizards' body, while the belly side is coated with soft
scales. The scales are bead-like and are predominately dark black or brown on the top and
bottom of the lizard. Yellow spots are scattered along the tail and the neck. Younger individuals
have thicker bands and larger blotches of yellow on their bodies when compared with the
adults.
Their grooved teeth are on the lower jaw bones, along with the venom glands, which are
arranged at the rear edge. The venom passes from these glands through a channel to the roots
of the grooved teeth. The venom is drawn into an inflicted wound by capillary action as the
lizard chews its prey.
Range:
They are found throughout central and western Mexico, southward to northern Central
America. They prefer semi-arid rocky regions. The areas are sparsely vegetated canyon
bottoms, open forest, and washes. These lizards are often found on rock ledges.
42
Mexican Beaded Lizard (cont.)
Diet:
Their diet consists of small mammals, birds, lizards, frogs, insects, and eggs of birds and reptiles.
All their prey is swallowed whole, except for eggs, which are broken first.
Life History:
The breeding season is in February and March and copulation lasts 30 to 60 minutes. About 2
months later, females lay 3 to 13 elongated eggs and bury them at a depth of about 5 inches.
The female then abandons the eggs. Incubation takes about 6 months. Each hatchling may be
up to 7 to 8 inches long.
The Mexican Beaded Lizard has very few enemies besides humans, coyotes, and some raptorial
birds. Having few natural enemies gives the hatchlings a greater chance for survival.
They spend more than 95% of their time hidden in shelters, like rocky crevices or burrows. They
come out to forage when temperatures are "just right" (at night during the hotter months, or
during the day during the cooler months).The Mexican Beaded Lizard uses their venom not only
to kill their prey, but also to subdue potential predators such as humans, coyotes and raptors.
The lizard also gapes and hisses to fend off their enemies.
Conservation:
Humans are not only a threat to the Mexican Beaded Lizard because they kill them for fear of
their venom, but are also destroying the habitat upon which these lizards depend.
They are protected under the Convention on International Trade in Endangered Species of Wild
Flora and Fauna (Appendix II) and are classified as "Vulnerable" by the International Union for
the Conservation of Nature and Natural Resources (IUCN).
Fun Facts:
When food is scarce, the Mexican Beaded Lizard lives off fat reserves in their tail. Fat is stored
in the tail of the lizard making them appear swollen. After the fat reserves are used up the tail
appears thin again.
Unlike venomous snakes, beaded lizards can't forcefully eject the toxin from their venom
glands; instead, they have to chew the venom into their victim.
43
San Esteban Island Chuckwalla
Source: 1- https://www.arkive.org/san-esteban-island-chuckwalla/sauromalus-varius/, 2-
http://www.torontozoo.com/ExploretheZoo/AnimalDetails.asp?pg=778, 3-
https://www.houstonzoo.org/animals/san-esteban-island-chuckwalla/
Description:
The San Esteban Island chuckwalla is the largest of its kind. The head is relatively small
compared to the rest of the body and has irregular, black coloring on the snout and around the
eyes. This gives way to splotches of tan or straw, along with black, throughout the rest of the
body. Fine scales give the impression of fine sandpaper and the skin is loose, particularly
around the neck and shoulders where it hangs in folds.
The eyes lie back from the snout and to the side of the head; ear openings are directly behind
these. They have no external structure, just a flap of scale to protect the eardrum. The torso is
flattened on top, and the sides roll gently outwards, giving an impression of a thick pancake.
The tail is long and stout with a blunt tip. Its whole surface is fissured and the scales are
prominent giving it a rough, coarse, segmented appearance. Males tend to be larger than
females, whose coloring is slightly duller and less splattered in effect. Except for size, the young
are identical to their parents.
Range:
Found only on the small islands of San Esteban, Roca Lobos and Pelicanos in the Gulf of
California. Chuckwallas occupy open flats, rocky outcrops, dry canyons and washes, often being
found near large rocks and boulders.
44
San Esteban Island Chuckwalla (cont.)
Diet:
Chuckwallas are primarily herbivorous, feeding on a variety of fruit, leaves, buds, succulent
stems and flowers, with some species supplementing their diet with the occasional insect.
Life History:
This diurnal lizard emerges in the morning and basks in the sun to raise their body temperature
before foraging for food. When danger is sensed, chuckwallas display a unique defensive
strategy of evading a potential predator. The threatened animal scurries into a rock crevice
where they firmly lodge themselves by inflating their lungs, thereby making removal by a
predator almost impossible.
Relatively little is known about the reproductive biology of the San Esteban Island chuckwalla.
Chuckwallas generally lay a clutch of between 5 and 16 eggs in June to perhaps August,
although some females may not lay eggs every year.
Conservation:
Many were captured for the ever escalating U.S. pet trade. In addition many are being killed by
uninformed people who confuse them with the venomous Gila monster. However, the most
devastating threat lies with the introduction of invasive species and the resulting degradation
of desert habitat. They are endangered in the wild.
Fun Facts:
They are a prime example of ‘insular gigantism’, the tendency of small mainland animals to
increase in size once established on an island due to fewer natural predators.
Chuckwallas gain all of their water requirements from the plants they eat. They do not drink;
waste is eliminated as salty crystals.
45
Sonoran Black Iguana
Source: 1- https://detroitzoo.org/animals/zoo-animals/sonoran-black-iguana/
Description:
The Sonoran black iguana is predominantly black, but the dorsal surface may show black bands
on a grayish background. Most have black mottling on their backs. The color may also lighten
after basking in the sunlight, with yellowish and orange markings becoming evident along the
sides. Their tail is ringed with rows of sharp, curved spines.
Range:
The Mexican States of Sonora and Sinaloa.
Diet:
They eat mainly legume fruits and other plant matter, sometimes rodents, bats, frogs, small
birds (and bird eggs), crustaceans and a variety of insects.
Life History:
After a gestation period of approximately 40 days, they dig a burrow about 1.5 feet deep and
lay two to 25 eggs. The can reach a size of four feet and weigh up to 5.5 pounds.
Conservation:
According to the IUCN, their conservation status has not been assessed.
Fun Facts:
They are the fastest lizards on earth and has been recorded running at speeds of up to 30 mph.
46
Snakes Central American Bushmaster
Source: 1- https://animaldiversity.org/accounts/Lachesis_muta/, 2-
http://www.centralfloridazoo.org/animals/south-american-bushmaster/
Description:
Bushmasters are large snakes, with individuals often exceeding 6.5 in length, and with the
potential to grow over 11.5 feet; these are the longest venomous snakes in the Americas and
the second longest venomous snake in the world. The body ranges from reddish-brown, tan, or
even a pinkish color, with very distinct dark, diamond-shaped markings down the back, often
edged with yellowish coloring. They have light colored bellies and usually a dark stripe
extending from the eye to the back corner of the mouth. The scales are heavily keeled above
(shaped like the bottom of a boat) and there is typically a ridge going down the center of their
back.
Range:
In Central America, bushmasters can be found in tropical forest areas of Panama, Costa Rica
and Nicaragua. In South America, their range consists of tropical areas of Brazil, Ecuador,
eastern Peru, Bolivia, the Guianas, Colombia, Trinidad and Venezuela.
Bushmasters primarily inhabit tropical moist forested areas. In addition, they live in habitats
that receive plenty of precipitation, and maintain temperatures of 75 degrees Fahrenheit or
more. Due to this preference, bushmasters are only found at altitudes below 3,280 feet.
47
Central American Bushmaster (cont.)
Diet:
Bushmasters are crepuscular or nocturnal predators that mostly eat small mammals, such as
rodents, in the wild. Birds and reptiles may occasionally be eaten too. Bushmasters are mainly
ground-living, sit-and-wait predators; they conceal themselves near areas of rodent activity and
wait for their prey to come within striking range.
Life History:
Bushmasters are oviparious (egg playing), typically laying a clutch of 5 to 19 eggs in an agouti
burrow. Bushmasters are the only egg-laying pit vipers in the New World. The females brood
the eggs, which have an incubation period of roughly 60 to 79 days. They do not eat during
incubation and only leave the nest briefly to drink. The young hatch at approximately 12 to 20
inches with bright orange or yellow tail tips, used to lure prey; this color fades over time. They
gain their adult coloring at 1 to 2 years old and reach sexual maturity at about 4 years old.
Bushmasters are solitary except during mating. Males find females by following a scent trail.
During the courtship, a male will rub the female's head and flicks his tongue across the female's
body. This can escalate to the male flipping himself upside down to rub his back on the female's
and striking the female with his body. If successful, the pair can mate for over five hours.
Bushmasters are usually active at dusk or after dark. Many of their habits are unknown as they
are so secretive.
Conservation:
Bushmasters are listed as vulnerable under the IUCN Red List due to habitat destruction.
Fun Facts:
Due in part to their large size, bushmasters produce much more venom than many other
species of vipers. For comparison, a bushmaster produces eight times more venom than an
American copperhead.
The bushmaster's tail ends with a thorny spine which it sometimes vibrates when disturbed in a
similar manner to rattlesnakes. This led to some calling it "the mute rattlesnake".
48
Emerald Tree Boa
Source: 1- https://animaldiversity.org/accounts/Corallus_caninus/, 2-
http://www.elpasozoo.org/Americas/emerald-tree-boa
Description:
Emerald tree boas are called "emerald" because of the exquisite green coloration on their
dorsal surfaces. Many populations have striking white markings occurring along the dorsal
midline, although some individuals lack them. Other individuals have black coloration on the
dorsum. Juveniles range from a brown to red color. Emerald tree boas can grow to be over 6.5
feet in length.
Range:
Emerald tree boas are found in lowland tropical rainforests in the Amazonian and Guianan
regions of South America.
Emerald tree boas are found at elevations ranging from sea level to 3280 feet above sea level.
They are arboreal species that spend most of their time in the rainforest canopy foliage.
Although they are arboreal, they do occasionally descend to the ground to bask in the sun. They
are found in areas that receive an excess of 59 inches of rain annually.
Diet:
Emerald tree boas are nocturnal predators of rodents, lizards, and opossums. Observations
strongly suggest that emerald tree boas are ambush predators that hang near the ground and
angle their heads downward to ambush passing rodents.
49
Emerald Tree Boa (cont.)
Life History:
They are viviparous (giving birth to living young that develop within the mother's body rather
than hatching from eggs) species with a gestation period of 6 to 7 months. Breeding does not
typically begin until females are 4 to 5 years old and males are 3 to 4 years old. These snakes
typically give birth to 5 to 12 young at a time, but offspring can number as many as 20. Emerald
tree boas typically breed every other year. The typical breeding season is between April and
July.
Emerald tree boas spend most of their time in wet, lowland rainforests, living in the canopy
foliage of trees and in shrubs. During the day they remain inactive, looped over a horizontal
branch. They form an ellipsoidal coil with their bodies, with the head in the center. As ambush
predators, they catch most prey by snatching them off the ground as they hang from these
branches.
Conservation:
The conservation status of this species is unknown, as it is not in the IUCN database, and CITES
does not list it as a species of concern.
Fun Facts:
The young are a reddish-brown color. By four months, they begin to develop their adult, green
coloration.
Living in tropical rainforests, these snakes drink by lapping water from leaves collected in their
coils.
50
Western Diamondback Rattlesnake
Source: 1- https://www.desertmuseum.org/kids/oz/long-fact-
sheets/Diamondback%20Rattlesnake.php
Description:
The Western diamondback rattlesnake is a heavy bodied snake with a triangular shaped head.
There are two dark diagonal lines on each side of their face running from the eyes to its jaws.
They have dark diamond-shaped patterns along their back. The tail has black and white bands
just above the rattles. They range in size from 3 to 5 feet long with a few reaching 7 feet long.
Range:
This species ranges throughout the southwestern United States (Arizona, California, New
Mexico, Oklahoma and Texas) and northern half of Mexico. They can be found living in deserts,
grassy plains, forests, rocky hillsides and areas along the coast. They live in elevations from
below sea level up to 6500 feet.
Diet:
They eat mice, rats, rabbits, gophers, ground dwelling birds, lizards and other small animals.
51
Western Diamondback Rattlesnake (cont.) Life History:
Western diamondbacks are pit vipers. This means that they have a heat sensing pit (loreal pit)
located behind each nostril that can detect differences in temperature, sometimes differences
that are only a fraction of a degree apart. The heat given off by an animal is detected by the
snake helping them to determine predator from prey. They will often spend the hot daytime
hours coiled in the shade of low-growing shrubs, piles of natural or artificial debris or rocks.
They will also utilize underground burrows of other animals. In the winter, they retreat into
caves or similar places to hibernate.
Conservation:
Currently, western diamondback rattlesnakes are not threatened or endangered.
Fun Facts:
The rattle of the rattlesnake is made up of a protein called keratin (the same protein that your
hair and fingernails are made of). A new segment is added each time a rattlesnake sheds.
Because of this, and the fact that segments can break off, you really can't tell a snakes age by
counting the segments.
A rattlesnake can move their rattle back and forth 60 or more times per second.
Their fangs are one inch long.
52
Colorado Desert Sidewinder
Source: 1- http://www.californiaherps.com/snakes/pages/c.c.laterorepens.html, 2-
https://www.inaturalist.org/taxa/30753-Crotalus-cerastes-laterorepens
Description:
They are a heavy-bodied venomous pit vipers with a thin neck, a large triangular head, and a
thick tail with a rattle on the end made of loose interlocking segments. The scale over each eye
is enlarged and raised up over the eye giving the appearance of a "horn" over each eye. These
scales can fold down over the eyes to protect them when the snakes is buried or crawling in
underground burrows. They have two loreal pits, one on each side of the front of the head
above the mouth that are used to sense heat when hunting warm-blooded prey.
They are pale cream, tan, brown, pink, or grayish back color usually closely matches the soil
surface allowing the snake to blend in with the background. They have around 40 darker
blotches on their back and a dark stripe that runs through each eye. They can reach 1.5 to 2
feet in length.
Range:
They are found in an area that centers on the Colorado Desert in Southern California. They are
also native to the Sonoran Desert in the Southwestern United States and Northwestern Mexico.
They inhabit areas of wind-blown sands, especially where sand dunes are topped with
vegetation. Also found in hardpan (hard layer of clay), open flats, rocky hillsides, and other
desert areas, especially those grown with creosote bush (an evergreen shrub), where the
terrain is open, not obstructed by too many rocks or vegetation, allowing the broad sidewinding
locomotion.
53
Colorado Desert Sidewinder (cont.)
Diet:
They eat mainly lizards when young, and increasingly larger prey including small rodents as they
grow into maturity.
Life History:
They are primarily nocturnal and crepuscular during periods of excessive daytime heat, but also
active during daylight when the daytime temperatures are more moderate. They are not active
during cooler periods in winter.
They move with a sidewinding locomotion, throwing raised loops of the body to the side to
push itself forward in an s-shaped curve. A sidewinders trail looks like a series of parallel j-
shaped lines pointing roughly 45 degrees from the direction of movement.
They are ambush hunters, they sit buried beneath the surface of loose sand with just the top of
the head showing, near kangaroo rat tunnels, and lizard or rodent trails, then strikes the prey
and will either start to consume its prey right away or release the prey, then follow the trail of
their envenomated prey and will eventually swallow them whole once the prey has succumbed
to the venom.
The females start bearing young at three years of age and breed annually. Their breeding
occurs in the spring. Two to 18 young are born from July to September.
Conservation:
According to the IUCN they are a species of least concern.
Fun Facts:
Young snakes may use their tail to lure their prey (caudal luring.) They coil up and lie still, raise
up the tail and wiggle it.
