La Selva Biological Station

Habitat
In lowland moist and wet forest, the Strawberry Poison-dart lives in undisturbed areas or abandoned clearings. It may also inhabit cacao plantations.

Range
This frog is prolific on the humid Caribbean side from premontane slopes in Nicaragua through Costa Rican lowlands up to 900 m and into northwestern Panama.

Physical Description
This poison-dart is one of the most prominent frogs in Central America. Its brilliant red head and back and blue-to-purple legs comprise a coloration distinct from all other frogs with the exception of the Granular Poison-dart Frog (Dendrobates granuliferus); the Blue-jeans, however has smooth skin, whereas the Ganular has rough skin on its back.

Subpopulations of this species exhibit remarkable variation in color in different parts of its range. For example, in Nicaragua this species has scarlet back and vibrant purple legs. In Bocas del Toro of northeastern Panama, the species may be blue or green on its back with white, yellow, or brown spots.

Biology and Natural History
The Strawberry Poison-dart Frog, also called the Blue-jeans Frog, is one of the most ‘popular’ amphibians in its region. This bright, charismatic species is active during the day and has a high population density, making its charming figure frequently found in certain areas of Costa Rica. This frog reproduces all year long in areas without a long dry season, and males can be heard calling all day with a buzz or chirp. Their small bodies can be seen or sometimes heard moving around leaf litter as they walk and hop.

Though small, males of this species are aggressively territorial. During the day, males perch on rocks, trees, or fallen logs, and make calls. These are both to attract females to mate as well as to intimidate trespassing males. If an intruder persists and calls back, a wrestling competition may result for up to 20 minutes. The males stand upright on their hind legs and grapple for dominance. Once one is pinned for several minutes he will leave after the winner releases him.

The fascinating reproductive process of this species has captured the interest of biologists and tourists alike. When a female meets a male, he leads her to a place to lay their eggs, such as in a curved leaf or in moist leaf litter. Unlike many frogs, the male does not climb onto the female’s back in amplexus, but instead the pair stands vent to vent, or with their tails together. The female lays 3 to 4 eggs, the male fertilizes them, and his mate leaves. The parental care beginning at this stage is unmatched by other amphibians. The male keeps the eggs moist by emptying his bladder on them. He also eats any eggs that are infected with fungi or that do not develop, as well as any eggs left by other males. Tadpoles hatch after one week, when the female returns. One to four tadpoles at a time squirm onto her back, and she carries each one to a different plant or leaf stem that is holding water—bromeliads are often the choice. These carefully chosen nests are sometimes in the canopy, high up from the frog’s otherwise ground-level habitat. Amazingly, the tadpole chooses its spot by vibrating when the mother approaches a desirable spot. Each tadpole is placed in a separate plant, where the mother leaves it with 1 to 5 unfertilized eggs for protein and nutrients. For more than a month, the female returns every few days to feed her young.

The frog’s bright colors warn off predators because the colors signal the toxicity for which the Poison-dart is named. The Strawberry Poison-dart Ffrog is not known to be lethal to man, but its skin secretions may have unpredictable effects on humans. Other species in this frog’s family have been used to make blowgun darts especially lethal. The most lethal animal toxin known belongs to a frog (Phyllobates terribilis) related to the Blue-jeans; poison from a single individual can kill twenty thousand mice or ten adult humans. Needless to say, brightly colored relatives like the Blue-jeans have few predators, and once it reaches adulthood, this frog can live for 5 or 6 years. As eggs, however, this species is preyed upon by fungi, worms, snakes, and even other Blue-jeans.

Diet
The Poison-dart sustains itself on small invertebrates. Ants and mites comprise 90% of the frog’s diet. The alkaloids in the ants contribute to, but do not determine, the frog’s degree of toxicity.

Height/Weight
Adults of this small species are generally 19 to 24 mm (or ¾ to 1 in) long.

Taxonomy
Order: Hylidae
Family: Dendrobatidae

Habitat
Widely adapted and common, the terciopelo is no stranger to lowland moist and wet forests and premontane moist, wet, and rainforest. It is less common through dry forest zones, although it may persist along rivers through such forest. In human-controlled areas where rat populations have done well, this viper is not shy. Banana plantations are a particular haunt of the terciopelo because of their rats.

Range
It can be found on the Pacific coast from some parts of Mexico down to Ecuador; on the Atlantic coast, down to Colombia.

Physical Description
This snake can grow to a large size as an adult, but has a distinct coloration pattern both as a juvenile and adult. Pale yellow or cream-colored bands crisscross the back and sides of the body, making spaces for a dark diamond pattern. The luster of these dark triangles is velvety, and the triangles connect slightly on the back which some describe as a butterfly or hourglass pattern. The head is large, triangularly shaped, and conspicuously wider than the neck. This pit viper has the deep, visible, heat-detecting pit between each eye and nostril. The eyes are large and have a vertical pupil. The scales along the head and back are keeled.

Biology and Natural History
This infamous viper’s large size, long fangs, and high venom production and toxicity are paired with an active and edgy disposition, making it one of the most dangerous creatures one can encounter in Latin America. It is the most dangerous snake in Central America and causes the most snakebite-related deaths among humans in countries like Costa Rica. Venom from this species contains an anticoagulant and causes hemorrhaging.

This nocturnal serpent is more active on the ground as an adult, but as a juvenile may function during the day and on low vegetation. Younger terciopelos have a yellow-tipped tail to draw the attention of frogs or lizards before ambushing them. Prey size increases as the individual snake grows larger.It passes the day coiled up and hidden in vegetation; at dusk it will hunt along roads or trails through dense grass and forest. It is not afraid of human dwelling areas. When it feels agitated, the fer-de-lance may vibrate its tail—the buzz is audible—before striking. It moves quickly when threatened. Other large vipers are more inclined to escape when they feel attacked, but the terciopelo is more likely to strike. It produces a lot of venom, so it is less reserved with this defense as other snakes.

Female terciopelos give birth to live young (as opposed to eggs) in litters of fewer than 10 to larger than 80 small snakes at a time.

Diet
Juveniles prey on arthropods, frogs, lizards, or other small vertebrates. Adults upgrade their diet to small mammals, such as rodents and opossums, and occasionally birds of an appropriate size depending on the snake.

Height/Weight
The full length of this snake can be more than 2 m; females are able to reach slightly longer body lengths than males.

Taxonomy
Order: Squamata
Family: Viperidae

Habitat
The bullet ant is active all over the forest, from the floor to the treetops. It is usually found on lianas and tree trunks close to the ground.

Range
This insect lives from Nicaragua down to the Amazon.

Physical Description
This long, black ant is distinct from other ants in Central America because it is enormous, second only to the Greater Giant Hunting Ant (Dinoponera gigantea). The bullet ant is hairier than fellow hunting ants.

Biology and Natural History
The colony burrows a nest with different entrances on the ground between tree buttresses. Some arboreal nests have also been discovered. Workers guard the nest against vertebrates and other insects, including other bullet ants. While these ants do live in colonies, individuals search for food alone. Foraging workers hunt insect prey and look for plant sap between dusk and dawn. They may also look for food among the trees during the day if it is cloudy.

The bullet ant has one of the most painful insect stings or bites that you can encounter in central America. Sometimes they fall from higher tree branches and attack when they encounter a large, frightening creature, such as a human. First the bullet ant bites; once the mandibles are securely squeezing the victim, the ant turns its abdomen to sting at the same time. While this may cause some pain and swelling, the venom does not cause sickness or death, and bullet ants are not encountered in droves and swarms like army ants.

Diet
This hunting ant eats insects, plant exudates, and sap.

Height/Weight
The bullet ant can reach 2.5 cm long.

Taxonomy
Order: Hymenoptera
Family: Formicidae

Habitat
The termites in this genus can survive in trees in most lowland tropical habitats from rainforest to savanna to mangrove forest.

Range
These insects can be found along the lowlands of most of Central America.

Physical Description The three castes of termites in a colony have very different functions and physiques. The soldiers have small brown bodies with dark heads and a long, pointed snout or beak used to squirt a defensive chemical. Workers are a similar size and shape, but have a rounded pale head and lack the squirting snout. The queen is enormous with an abdomen full of eggs and fat. She looks nothing like the workers and soldiers, but has a long yellowish body and cannot move herself.

Biology and Natural History
The most abundant tropical termites in the Americas, some Nasutitermes termites build their large, dark nests on tree trunks or large branches. Other termites in the same genus nest directly out from the ground, and there are species that even nest underground. A tree nest can be larger than a basketball, and up close looks like it is made out of sealed bits of paper. This is carton, a mixture of digested wood and termite feces that hardens into a strong, protective material.

The termites travel from the nest to rotting trees where they forage for food. They build tunnels covered in carton down the side of their home tree, over the forest floor, and to the food trees. The tunnels are distinctly a termite trait, which helps distinguish the termite nests from ant or wasp nests that can look similar high up in a tree.

One colony can have 5 or 6 thousand termites. One species, Nasutitermes corniger, can have giant nests with up to 1 million termites. Soldiers flood out of the nest when the colony is attacked, and expel a sticky, thick chemical called nasute glue from their snouts that smells like turpentine and is very irritating to the skin, particularly to the inside of the nose and mouth. This protection is effective against anteaters and several other predators. The workers, meanwhile, stay protected deep in the nest where they take care of the brood and the queen. They do not produce the nasute glue, but in swarms their biting can be a good deterrent. There is only one queen in the colony, and her job is mainly to produce eggs.

Diet
Arboreal termites get most of their nutrition from decaying wood material, which they chew up and bring back to the nest.

Height/Weight
Workers are 3 to 4 mm in length. Soldiers are approximately the same size. Queens can be 30 to 60 mm long.

Taxonomy
Order: Isoptera
Family: Termitidae

Habitat and Range
Both dry and moist forest habitats are suitable for the black witch.

This moth can survive as far north as southern Florida and as far south as Brazil and Peru, as low as sea level and as high as 3,048 m in elevation. At night it can be found hovering near lights both in towns on the coast and high up in the Andes Mountains.

Physical Description
This very large moth is patterned in different shades of brown and has one darker comma shape on each forewing. Females have an additional pink-purple marking across each wing.

Biology and Natural History
With the moniker from Mexican folklore, “Mariposa de la Muerte,” meaning “butterfly of death,” the black witch moth should perhaps be a little more frightening. Because it is mostly active at dawn and dusk, in these half-lit times the large moth’s flittering flight pattern resembles that of a bat. If disturbed while resting during the day, the moth will rush out of its hiding place, which also resembles a bat’s behavior. It should be noted that neither moths nor bats are dangerous.

This moth is drawn each night to bananas and fruits that grow high in the forest canopy. During daylight hours, black witches seek out darker corners of the forest such as tree hollows or rock crannies.

A capable distance flier, the black witch moth travels all over the continent throughout the year in unpredictable movements. The moth breeds in Mexico and even farther south, but from August to October it may be found in California, New York, Minnesota, Kansas, and even southern Canada.

Diet
As an adult, this moth sucks the juices of rotting fruit. As a caterpillar, it consumes the leaves of host plants mostly from the bean family (Fabaceae).

Height/Weight
An adult’s wingspan is about 15 cm; females can grow a little larger than males.

Taxonomy
Order: Lepidoptera
Family: Noctuidae

Habitat
The Central American bushmaster is found throughout Central America and parts of northern South America. This snake lives in moist tropical forests and usually stays close to a water source. They typically live in primary forests.

Physical Description
The Central American bushmaster is the longest pit viper in the world. It has a round, flat head and a level snout. The snake has a ridge of upturned scales running down the center of its body. It is usually light tan and has a pattern of dark diamond shapes that run along the length of its body.

Interesting Biology
The Central American bushmaster has two heat sensing pits on their face. These are used to detected warm-blooded prey.

The snake usually lays 10 to 12 eggs, rather than birthing live young like other snakes. They are the only egg-laying pit vipers in the Americas. Females coil around their eggs during incubation.

They have large stores of venom and deliver it through long fangs, which can sometimes be up to 1-inch long.

Bites from bushmasters can occur by accidentally stepping on the snake. Their venom is deadly and the bites can be fatal, so seek medical attention immediately if bitten. The venom is not as toxic as the venom of other snakes, but the bushmaster injects such a large amount of venom that it ends up being fatal. That said, these snakes are usually shy and bites are rare.

The Central American bushmaster is not officially protected, but it is in danger of extinction due to habitat loss.

Diet
Bushmasters eat birds and small mammals like rodents. They are ambush predators that sit and wait for their prey. They kill by biting and injecting venom. They then wait for their prey to die and will swallow them whole.

Height/Weight
The Central American bushmaster can grow up to 12 feet (4 m) long and weigh between 6.5 and 11 lbs (3 to 5 kilos).

Brief Taxonomy
Order: Squamata

Family: Viperidae

Habitat
The Chestnut-headed Oropendola prefers the canopy and edges in humid, forested regions.

Range
This large bird lives between southern Mexico and northwestern Ecuador.

Physical Description
This large dark bird builds its nest in conspicuous colonies-one can spot the chosen trees full of long, narrow sack nests from far away, as well as hear the loud, resonant kuk call from the vocal oropendolas. This oropendola can be identified by its mostly black body followed by a bright yellow tail, with a chestnut-colored head, pale blue eyes, and long ivory bill that starts high up on the forehead. Adults of both sexes are colored similarly, while juveniles are duller and take 2 years to develop complete adult plumage. This bird can be distinguished from the Montezuma Oropendola, which has a chestnut body and dark bill. The Chestnut-headed also uses calls that are deeper and more resonant than those of the Montezuma.

Interesting Biology
The oropendola's characteristic colonies of 12 to 50 long (56 cm) sacklike nests hang from the ends of branches of large trees that are prominent in a clearing or forest edge. The females weave these nests of fibers, vines, Spanish moss, and other materials. They also incubate and raise the two young without the help of adult males. During the nonbreeding season (June-December), flocks of these birds travel, searching for fruiting trees; their colonies often stay together, and return to their nesting trees when the breeding season resumes. Within a colony there is a sex ratio of 5 females for every male, indicating that their mating system is polygamous. The males do not fight, though, and show no sort of dominance hierarchy in the colony.

The dramatic disparity in numbers of each sex is due to the energy costs of raising males: females have to spend twice as much energy to raise male chicks, and males fledge when they are twice the weight of females; so when food is scarce, more male chicks die. In addition to this difficulty, Chestnut-headed Oropendolas lose their chicks to predators like toucans, snakes, opossums, and bats, but the most severe damage comes from botfly larvae.

The oropendolas are involved in a system of intriguing interactions as a result of botfly parasitism. Some colonies are built in trees that also host wasps or stingless (but biting) bees; the wasps and bees do not harm the chicks, but they do attack botflies, and the oropendolas resultantly have higher survival rates. Similarly, the Giant Cowbird (Scaphidura oryzivora), which is smaller than a female oropendola, are brood parasites-that is, they lay their own eggs in the nests of other birds. The female oropendola will spend energy feeding the cowbird chicks, but the cowbird chicks pick off botfly eggs and larvae from the oropendola chicks, so more of the oropendola chicks survive. However, oropendolas in trees with protection from wasps or bees do not need the cowbird chicks, so they prohibit cowbirds from laying or later remove the cowbird eggs from their nests. If oropendolas are not nesting in a tree with wasps or bees, they will permit the cowbird eggs in their nests. This dynamic is important to the oropendola's survival, because few chicks survive to fledging-but once grown, the survival rate is strong.

Diet
The agile Chestnut-headed Oropendola mostly forages in the canopy, as it hops, runs, and hangs on branches, looking for fruit or the nectar of large flowers like those found on the balsa tree; they may also descend to look for small frogs and lizards.

Height/Weight
Males are 35 cm long, females smaller at 27 cm; males (212 g) weigh twice as much females (110 g).

Brief Taxonomy
Order: Passeriformes
Family: Icteridae

Habitat
These bats inhabit lowland areas on both coasts where there are rivers, pools, or other bodies of water (including salt water) calm enough to fish in.

Range
Between Sinaloa, Mexico and northern Argentina, these bats are usually below 200 m in elevation.

Physical Description
This large bat is found in areas where it can hunt over open, relatively still bodies of fresh or salt water. It is covered in short reddish brown to orange brown fur with a pale middorsal stripe; the fur color can change from ammonia fumes in the roost. This bat has characteristic, very long legs and enormous feet, both of which help it gaff fish from the water. It also has a bulldog-like face for which it is named, with narrow, pointed ears and very small eyes in a flat, puffy face. The wings on this bat are pointed and long even for its size-it may have developed wings this long because of the obstacle-free setting in which it forages. Also because of its diet, this bat has a strong fishy odor.

Biology and Natural History
The bulldog bat usually forages independently, but has been seen sometimes flying in pairs over the water. To catch fish, the bat skims close to the water's surface, sending out echolocation pulses; when it detects a ripple or a small object breaking the water's surface, it dips its feet into the water for a distance of 10 to 20 cm, and sometimes gaffs a small fish or other prey item with its large feet and claws.

Each foot sweeps a path 3 to 4 cm wide; if it snags a meal, it takes the prey into its mouth, and usually will pause from hunting to hang upside down somewhere and eat. If it keeps the fish in the mouth, emitting sonar waves is more difficult; so sometimes, the bat will partially chew the fish, push the meat into the cheek pouches on the wings, and continue fishing. The bat eats its prey entirely, crunching the bones in its powerful jaws.

These bats may repeatedly leave and return to the roost all night between fishing trips. During the day they roost in colonies that generally number 75 individuals, but may have hundreds. These roosts are sometimes in hollow trees or buildings, but they prefer caves and sometimes are found in sea caves. An adult female will have one pup each year, and within the roost the females may form nursery colonies.

Diet
The fishing bulldog bat mostly eats fish, but also will consume insects or small crustaceans picked from the water surface, as well as insects caught in the air. They have been known to also eat smaller amounts of scorpions, crabs, and terrestrial insects.

Height/Weight
Adult males are usually largest, with a head and body length averaging 96.9 cm and a weight of 67 g (they may weigh as much as 90 g); females are 91.3 cm long and weigh 56 g. These bats have a wingspan of 60 cm.

Taxonomy
Order: Chiroptera
Family: Noctilionidae

Habitat
This toad lives in lowland premontane to lower montane regions up to 2,100 m, and is more common in disturbed areas and human settlement areas.

Range
The Giant Toad can be found from southeastern Texas to the Amazon basin in Peru and Brazil. This species has been introduced by humans to southern Florida, Hawaii, Australia, the West Indies, the Philippines, Taiwan, New Guinea, Fiji, Samoa, and other islands in the south and western Pacific.

Physical Description
This nocturnal toad is difficult to confuse with other species mostly because of its massive size. Another distinct trait is the pair of large, triangularly shaped poison glands (paratoid glands) on the sides of the neck. The Cane Toad also has bony ridges along the top of its head and scattered warts all over its skin. Its body color is brown to olive, with brown splotches on a dirty white or cream underside. It is not the most attractive toad, but its impressive diet and behavior make it an ecologically important species in the Tropics.

Biology and Natural History
The Cane Toad is truly a giant, the largest amphibian in Costa Rica and one of the largest frogs or toads in the world. It has an enormous range and is highly adaptive to different habitats, partly because it can and will eat anything it can.

This amphibian is surviving much better with habitat destruction and climate change than other amphibians. Unlike many frogs and toads, this one is more likely to naturally be found in secondary growth forests or open habitats instead of primary or closed canopy forests. As humans deforested new areas they widened the preferred setting for the Cane Toad. It is now so common in areas used for agriculture or other human needs that it is considered a pest in some regions. It posed a more serious problem in Australia, where the toad was introduced to reduce the beetle populations that damage sugar cane crops. The flaw in this design was that there were no predators in Australia for this large, poisonous toad, so the toad itself became a menace, breeding and dying in water used for livestock and poisoning the herds. Its presence is less harmful in many Central American areas, where the toad can be found under lit areas at night to eat insects.

This toad’s rapid reproduction rate contributes to its abundance. This species breeds all year, and females lay 5,000 to 25,000 eggs at a time, anchoring strings of these eggs to the bottom of a shallow or temporary pool. Although the eggs and tadpoles are toxic, aquatic creatures still eat them. Adults are much more toxic, and although they are still sometimes eaten by crocodiles, other reptiles, birds, or mammals, the glands in an adult contain enough poison to kill large animals. Adults can also eject their poison at an attacker.

One of the toxins in the Cane Toad can cause hallucinogenic responses, making it of interest both to ancient indigenous cultures in Central America and to contemporary scientists. Using the toad by any method is not the best vehicle for hallucinogenic experiences—the human reaction is unpredictable and this toad is potentially lethal.

Diet
The Cane Toad has a remarkably diverse diet, eating anything including insects, spiders, beetles, earthworms, slugs, snails, and ants, and even stinging or toxic prey like wasps, spiders and millipedes; the toad will also eat small vertebrates such as frogs, lizards, mice, and rats. It will consume plant matter and fruit if it needs to, as well as cat and dog food. Large Cane Toads have been known to eat small pets, such as kittens.

Height/Weight
This species tends to be larger in South America and Australia than in Central America. Female Giant Toads can grow to more than 1.5 kg (3.5 lbs) and 90 to 230 mm (9 in). Males are smaller, reaching only 85 to 145 mm in length.

Taxonomy
Order: Anura
Family: Bufonidae

Habitat and Range

This glass frog lives near rapid streams, both in cleared areas as well as the canopy level of trees. This species can be found from Mexico through Central America to Ecuador, Colombia, Venezuela, and the Guianas.

Physical Description

Glass frogs look similar to tree frogs, except that the eyes of a glass frog are oriented forward, whereas the eyes of a tree frog are oriented to the sides. This nocturnal frog stays camouflaged during the day on the underside of leaves, often above water. It is tiny, semi-translucent, and a leaf-green color; its appearance, paired with its tendency to freeze when approached, make this amphibian hard to spot.

If the glass frog is discovered, its fragile bones and some red veins are visible through a transparent belly. The yellow hands are also translucent, and the pale green skin with pale yellow dots matches leaf perches. To better disappear, the frog’s body is flat, and its total length is usually about an inch. The fingers and toes have enlarged, adhesive disks that help with climbing. Fleischmann’s Glass Frog has large, golden eyes that stay concealed when it sleeps during the day.

Biology and Natural History

More than 100 species of glass frogs live throughout Central and South America. Adults are most active on nights with light precipitation, which helps prevent them from drying out. They have to hide during strong rains, though, because their bodies are fragile. An adult can be knocked off its perch on a leaf by heavy rain, and some have been observed dying from a single direct hit by a raindrop.

Males are not tentative though, especially not with their territories. Males call in their high peep or wheet from under their leaves; if a desired female approaches or if an undesired male intrudes, the first male begins mewing. If the invading male persists, the conflict ends in an arboreal wrestling match; once one male is pinned down, he will leave after the winner releases him.

Meanwhile, females descend to levels closer to the streams where the males call, but only on nights during the breeding season. They intentionally search for their favorite males, engage in amplexus, lay their eggs on a leaf above a stream, and return to the tree tops. Adults try to time the hatching of the clutch with rain so that the tadpoles may be washed into the stream. If they are not flushed from the leaves, the tadpoles will wiggle off and drop into the water. With rain, the streams are cloudier, and better hide the tadpoles.

Diet

The diet of this frog is not well understood, but it probably feeds on small insects.

Height/Weight

An adult male Fleischmann’s Glass Frog is generally 19-28 mm long; larger females measure 23-32 mm.

Brief Taxonomy

Order: Anura
Family: Centrolenidae

Habitat
This macaw lives in the canopy of humid lowland rainforest; it can also be found in more open areas where its feeding tree still stands.

Range
From eastern Honduras down to northwestern Colombia and western Ecuador, this bird is found at elevations of up to 600 m or higher.

Physical Description/ Interesting Biology
These intensely colored birds recently became the focus of a desperate protection effort as their flocks dwindled to alarming scarcity. Deforestation has ravished their foraging lands, isolating and reducing the trees they rely upon for food.

These intelligent macaws can live more than 60 years with sufficient foraging grounds, and are a delightful (though rare) burst of color to see crossing gaps in the canopy overhead. The endangered Great Green Macaw is closely related to the Scarlet Macaw and is equally as bright in plumage. They are easily distinguishable because the head, shoulders and back of each species is draped in the color matching their name. The Great Green has a sturdier frame, heavier bill, and shorter tail than the Scarlet Macaw. Adults have a bright red forehead and pale facial skin streaked with red and black feathers. Their wing feathers are a radiant blue, the lower back is a pale blue, and the tail feathers are also scarlet and blue.

Along the Caribbean slope, this macaw migrates searching for the enormous swamp almond tree, Dipteryx panamensis. With their incredibly strong bills, the macaws penetrate the resilient nuts of this tree and rely on it almost entirely for food. They also require the hollow cavities of this tree for nesting and raising their young.

Sometimes this tree is left standing alone in pastures or somewhat open areas; the macaws come in squawking flocks of up to 15, often from far distances. They migrate seasonally according to where they can find fruit, and the trees that they remember and need are far apart and not all within preserved areas (and instead are often on private property). This means that the macaws may arrive to find their food source cut down and find themselves far from another Dipteryx. These birds are widespread but decreasing in number. They usually stay at an area with fruit for a few weeks or months and move on when food becomes insufficient.

This is just one example of many in which the survival of a species depends not simply on living in forest, or even a certain kind of forest, but particularly on another species. In a country like Costa Rica, the total number of 549 Great Green Macaws in 1998 sank to just 210 by the year 2000. The vulnerability of this species reflects the complex ecological repercussions of our actions and how dramatically important it is for us to understand the effects of our actions.

Diet
The Great Green Macaw relies heavily on the fruit of the swamp almond tree, Dipteryx panamensis.

Height/Weight
Adults reach a length of 79 cm and a weight of 1.3 kg.

Brief Taxonomy
Order: Psittaciformes
Family: Psittacidae

Habitat
This lizard prefers shady areas on the forest floor or near the base of large trees, particularly ones with large buttresses holding deep leaf litter. The ground anole can live in virgin rainforest as well as overgrown cacao plantations; lowland to premontane to lower montane zones; and moist to wet to rainforest.

Range
From eastern and southern Honduras down to central Panama, this animal can live from 2 to 1,500 m in elevation.

Physical Description
A small brown lizard, Norops humilis can have a broad dark band down its back and a lighter brown underside. The eyes are a bronze-speckled light brown. Males have a dewlap—an flap of skin on the throat—that is bright orange in this species. Other species have differently colored dewlaps. Females do not have a dewlap, although they may still have a patch of reddish skin on the throat; they might have a white stripe or row of spots on the back as well.

This lizard has a deep axillary pore or pocket in the armpit of each front leg. This pore is inhabited by parasitic mites.

Biology and Natural History
There are 21 species of Norops lizards in Costa Rica and 7 live in the southwestern region. This species, Norops humilis, is the most likely to be seen. An abundant, small, arboreal creature, N. humilis is diurnally active and commonly glimpsed perching on tree trunks, tree buttresses, or deep leaf litter on the forest floor. This is not basking behavior like other lizards—this species is a thermoconformer, and maintains its body temperature without relying on taking sun and shade. When perching, one often clings to the bark of a tree about 1.5 m off the ground with its head pointed down. When startled, this lizard will take an evasive route before diving under the leaf litter.

Much of the day’s energy is spent searching for prey. From its perch, the anole watches the leaf litter for small invertebrates, sprints after them, and returns to the perch. They may eat as often as once an hour. Nearly all of a female’s energy is spent looking for food. Males are more preoccupied with social behaviors, particularly defending territory and attracting females. Males therefore perch higher off the ground than females. An adult male spends several hours of his day showing off his dewlap. He stretches out the dewlap, and bobs his head up and down. If this display coincides with a female’s entrance into his territory, the male will court her by flashing his dewlap just for her before chasing her across the forest floor. If another male is bold enough to intrude, the resident male’s display may escalate to chasing and biting. A male is fiercely territorial towards other males to ensure his access to the females (1 to 3) that overlap his territory. A female defends her territory solely to ensure food supply.

Rainfall brings an increase in courtship and reproduction, although these lizards may mate all year. A female will lay one large egg once a week through the rainy season, and once every two weeks in the dry. This ability to reproduce so often is one reason this lizard is prolific in the forests of Costa Rica. Few norops lizards live longer than a year. They are common prey for many larger animals, from larger lizards, vine snakes (and other serpents), to motmots and trogons. Young, small anoles become food for large invertebrates, such as mantids and katydids.

Diet
Norops eat quite the variety of arthropods, including but not limited to spiders, cockroaches, crickets, caterpillars, beetles, flies, termites, hemipterans, and centipedes. They do not like ants.

Height/Weight
An average total length for this species is 114 mm, the snout-vent portion of which is 40 mm. The tail is approximately 60% of its total length. Females tend to be smaller than males by a few millimeters.

Taxonomy
Order: Squamata
Family: Iguanidae

*Note: The taxonomical categorization of this species is currently debated.

Habitat

Like other millipedes in Central America, this species sticks to dark, humid nooks within the forest, favoring rotting trees, piles of leaf litter and soil, caves, and other concealed places.
Physical Description

With a thick, shiny armor and yellow-orange and black striping, this millipede may appear threatening. Its body is comprised of 20 segments, most of which have two pairs of legs.

Millipedes and centipedes are often confused with one another. Millipedes have legs that come in pairs, and depending on the species and how fast they are moving, you can notice the legs moving two by two. Millipedes tend to move slower than centipedes, so if you see one of these many-legged insects racing across the forest (or house) floor, it is probably not a milipede.

Biology and Natural History

This insect is a commonly found friend of forest floors, where it sifts through the leaf litter, chewing up decaying wood and other plants. These millipedes are greatly important to the health of the forest, as they assist the decomposition of dead or dying plant matter.

Partly because it is an herbivore, the millipede does not move quickly or have venom like the hasty, biting centipedes which hunt other insects. This species of millipede has a tough exoskeleton, a hefty size, and bright warning colors. Rather than run or bite, it will instead curl up and release an unpleasant liquid from its rear which contains hydrogen cyanide and benzaldehyde. This liquid can ooze or eject from the millipede, and while it is not potent enough to threaten human health, it is better to wash the skin it touched.

Diet

Mostly plant matter and decaying wood make up the meals for this millipede.

Height/Weight

Adult females of this species grow to about 10 cm. Males are a little smaller.

Taxonomy

Order: Polydesmida
Family: Platyrhacidae

Habitat

Scorpions as a group live in a variety of habitats, but most species are adapted to a specific one. Some live in trees, others on the ground beneath leaves; certain species survive well in desert conditions, and others require humid forest.

Range

From the southwestern United States, Mexico and Central America, different kinds of scorpions extend down into South America.

Physical Description

The scorpions in Costa Rica have the familiar figure of scorpions in other parts of the world. This arachnid has eight legs, plus large pinchers in front called pedipalps which move like lobster claws. Scorpions also have chelicerae, a set of thicker jaws around the mouth. The body ends with a long segmented tail that terminates in a stinger.

Biology and Natural History

Scorpions are feared in many regions for having a painful and dangerous sting. In Central America alone, there are over 400 species of scorpions.

They will kill each other, however, so mating is a delicate process. A male will approach a female and the two will lock pedipalps or chelicerae then move back and forth in a sort of dance until they can make an exchange. The male releases a sperm packet onto the ground, then steps backward until the female moves over this packet and her body picks it up. Then the two separate. When she gives birth, the mother will keep her larval young on her back until they molt and look like small scorpions. After a series of molts over 1 to 3 years, they are mature adults.

Diet

Scorpions are predacious. They hunt insects and spiders, and will eat other scorpions as well. The species that are adapted to desert terrain can survive for months without water. Those accustomed to a humid forest habitat can die of dehydration after just a few days.

Height/Weight

Scorpions may vary in size; in Costa Rica some species are rather small, reaching only 6 to 7 cm, head to tail.

Taxonomy

Order: Scorpiones