Reforestation

Reforestation
Reforestation

Reforestation is the growth of new trees in an area that has been cleared for human activities. It can occur naturally or be initiated by people.

Many areas of the eastern United States, such as the New England region, reforested naturally in the nineteenth and early twentieth centuries after farmland that had been abandoned was allowed to lie fallow for decades.

After an area has been logged, environmentalists, as well as the commercial logging industry, advocate planting trees rather than waiting for natural regrowth because the process of natural regeneration can be both slow and unpredictable.

Slash and Burn Agriculture

Slash and Burn Agriculture
Slash and Burn Agriculture

Slash-and-burn agriculture, also called swidden agriculture, is a practice in which forestland is cleared and burned for use in crop and livestock production. While yields are high during the first few years, they rapidly decline in subsequent years, leading to further clearing of nearby forestland.

Slash-and-burn agriculture has been practiced for many centuries among people living in tropical rain forests. Initially, this farming system involved small populations.

Therefore, land could be allowed to lie fallow (unplanted) for many years, leading to the full regeneration of the secondary forests and hence a restoration of the ecosystems. During the second half of the twentieth century, however, several factors led to drastically reduced fallow periods.

Soil Contamination

Acid mine drainage causing contamination of water and soils
Acid mine drainage causing contamination of water and soils

Soils contaminated with high concentrations of hazardous substances pose potential risks to human health and the earth’s thin layer of productive soil.

Productive soil depends on bacteria, fungi, and other soil microbes to break down wastes and release and cycle nutrients that are essential to plants. Healthy soil is essential for growing enough food for the world’s increasing population. Soil also serves as both a filter and a buffer between human activities and natural water resources, which ultimately serve as the primary source of drinking water.

Soil that is contaminated may serve as a source of water pollution through leaching of contaminants into groundwater and through runoff into surface waters such as lakes, rivers, and streams.

Addax

Addax
Addax

The addax is a large antelope whose coat is gray-brown in winter and almost white in summer. Black hair sprouts from its forehead and from the end of its 10- to 14-inch (25- to 36-centimeter) tail. Two long, thin, spiral horns (each twisting two or three times) extend up and back from the front of the animal’s head.

An average addax measures about 5 feet (1.5 meters) in length and about 3 feet (1 meter) in height at its shoulder. It weighs between 132 and 287 pounds (60 and 130 kilograms). A female addax usually gives birth to one infant after a gestation (pregnancy) period of eight to nine months.

The addax is at home in a desert environment. It receives all the water it needs from the plants it eats. With its long stride and splayed (spread apart) hooves, the animal easily crosses vast sandy areas in search of sparse desert vegetation. Addax usually travel at night in groups of 5 to 20.

Giant Armadillo

Giant Armadillo
Giant Armadillo

The giant armadillo is the largest member of the armadillo family, which is composed of twenty–one species. Eleven to thirteen moveable bony plates cover a giant armadillo’s back, and three to four flexible bands cover its neck.

Its body is dark brown, while its head, tail, and a stripe around the bottom of its shell are whitish. A giant armadillo measures 30 to 39 inches (76 to 99 centimeters) from the tip of its nose to the end of its body. Its tail is about 20 inches (50 centimeters) long. It weighs between 44 and 88 pounds (20 and 40 kilograms).

Unlike certain members of the armadillo family, the giant armadillo cannot roll into a ball, protected by its body armor. To escape from danger, the giant armadillo quickly digs itself into the ground using the long claws on its front legs. The animal also uses these claws to dig for ants, termites, worms, spiders, and other insects which it feeds on at night.

African Wild Ass

African Wild Ass
African Wild Ass

The African wild ass is one of only seven surviving species of equids (horse family). Of these seven species, five are threatened or endangered. The smallest member of the horse family, the African wild ass stands about 4.5 feet (1.5 meters) tall at the shoulders and weighs about 550 to 600 pounds (250 to 275 kilograms).

It has a gray coat with a white belly and a dark stripe up its back. With its long ears and short stubby mane, the African wild ass looks like its cousin, the American domestic donkey, and is in fact the donkey’s ancestor.

The African ass has strong teeth and sturdy narrow hooves. It eats the tough grasses and shrubs of the desert. Although its teeth wear down from grazing, they continue to grow throughout the life of the animal.

Aye-aye

Aye-aye
Aye-aye

The unusual-looking aye-aye is covered with a coat of coarse blackish-brown hair, which overlays a denser coat of short white hair. The animal has very large, sensitive ears that stick out from its small, rounded head. It has sharp, rodent-like incisor (front) teeth and long, claw-like fingers and toes.

An average aye-aye is 15 to 18 inches (38 to 46 centimeters) long from the top of its head to the end of its body. Its bushy tail measures 16 to 22 inches (41 to 56 centimeters) long. The animal weighs between 4.4 and 6.6 pounds (2 and 3 kilograms).

While an aye–aye eats bamboo shoots, sugarcane, and some small animals, most of its diet consists of fruit (especially coconuts) and wood-boring insect larvae. Using its powerful incisors, the aye-aye breaks into coconuts, then scoops out the pulp with its very long, thin middle finger.

Golden Bandicoot

Golden Bandicoot
Golden Bandicoot

The golden bandicoot belongs to the order of mammals known as marsupials, whose young continue to develop after birth in a pouch on the outside of the mother’s body. The animal’s coarse fur is a mixture of yellow-orange and dark brown hairs, giving it a golden appearance.

It has a long, tapering snout and short, rounded ears. An average golden bandicoot measures 9 to 19 inches (23 to 48 centimeters) from the top of its head to the end of its body and weighs about 3 pounds (1.4 kilograms). Its tail is 3 to 8 inches (8 to 20 centimeters) long.

Golden bandicoot are nocturnal (active at night). During the day, they remain in their nests built on the ground, in a hollow, or in a rock pile. At night, the very quick, agile, and aggressive animals search for their diet of insects and worms.

Gray Bat

Gray Bat
Gray Bat

Contrary to its name, the gray bat is reddish-brown in color. Its forearm measures 1.6 inches (4 centimeters) long, and it weighs 0.35 ounce (10 grams). The gray bat differs from other species of the Myotis genus (a group with similar characteristics) in that its wing membrane (a double membrane of skin) attaches to its ankle instead of the side of its foot.

The gray bat feeds at night on insects, particularly mayflies and mosquitoes. It roosts in two different types of caves throughout the year.

Female gray bats begin hibernating immediately after mating in the fall; adult males and juveniles follow several weeks later. In late March, the females emerge from hibernation, while the rest emerge about a month later. Using sperm they have stored all winter, female gray bats fertilize their eggs after hibernation, giving birth to a single infant around late May.

Townsend’s Big-eared Bat

Townsend’s Big-eared Bat
Townsend’s Big-eared Bat

The Townsend’s big-eared bat is named for its large ears, which are from 1 to 1.6 inches (2.5 to 4 centimeters) long. In contrast, the bat’s body length is 1.8 to 2.7 inches (4.5 to 7 centimeters), its tail length is 1.4 to 2.1 inches (3.5 to 5.3 centimeters), and its forearm length is 1.4 to 2 inches (3.5 to 5 centimeters). The average Townsend’s big-eared bat weighs between 0.18 and 0.46 ounce (5 and 13 grams).

Townsend’s big-eared bats feed primarily on moths, which they locate through echolocation (sonar). In this process, a bat emits high-pitched sounds that echo or bounce off its prey. The bat’s sensitive hearing picks up the echo. From that sound, the bat can determine the size, shape, and location of its prey.

Male and female Townsend’s big-eared bats come together in late fall or early winter to mate and hibernate. The females store the sperm until early spring, when they fertilize their eggs. After a gestation (pregnancy) period of 56 to 100 days, they give birth to a single infant, which they nurse until fall.

Grizzly Bear

Grizzly Bear

The grizzly bear, a subspecies of the brown bear (Ursus arctos), is one of the largest land mammals in North America. An average male grizzly has a head and body length of 6 to 8 feet (1.8 to 2.4 meters), stands 3.5 to 4 feet (1 to 1.2 meters) at its shoulder, and may weigh up to 800 pounds (360 kilograms).

The smaller female grizzly weighs between 200 and 400 pounds (90 and 180 kilograms). The grizzly bear is so-named because its thick, light brown to black fur is streaked with gray, giving it a “grizzled” look. Grizzly bears have short, rounded ears, humped shoulders, and long, curved claws.

Although grizzly bears are omnivores (they eat both plants and animals), most of their diet consists of vegetation: fruits, berries, nuts, and the bulbs and roots of plants. They also eat ants and other insects.

Sun Bear

Sun Bear
Sun Bear

The smallest member of the bear family, the sun bear has an average head and body length of 3.5 to 4.5 feet (1 to 1.4 meters). Its shoulder height is 26.6 inches (67.5 centimeters) and its weight is between 60 and 140 pounds (27 and 64 kilograms).

The animal’s short tail extends only 1 to 3 inches (3 to 7 centimeters). The fur on the sun bear’s body is very short and black; the fur on its muzzle is almost white. Most animals of this species have a white to yellow-orange horseshoe-shaped marking on their chests.

The sun bear’s curved and pointed claws make it an excellent climber. It spends most of its day sleeping or sunning on a platform it builds in trees 7 to 20 feet (2 to 6 meters) above the ground.

American Bison


The American bison (commonly known as the buffalo) has a massive body, humped shoulders, and pointed horns that curve up and in. In winter, its coat is dark brown and shaggy.

In the spring, this coat is shed and replaced by one that is short and light-brown. Hair on the head, neck, shoulders, and forelegs remains long and shaggy throughout the year. A beard also hangs from the chin of the animal’s huge, low-slung head.

An average American bison has a head and body length of 7 to 12.5 feet (2.1 to 3.8 meters) and a shoulder height of 5 to 6.5 feet (1.5 to 2 meters). It weighs between 700 and 2,200 pounds (320 and 1,000 kilograms). The animal’s relatively short tail is 12 to 35 inches (31 to 89 centimeters) long and ends in a tuft of hair.

European Bison

European Bison
European Bison

European bison (often called wisent, from the German word for “bison”) are the largest land mammals in Europe but are slightly smaller than their close relative, the American bison.

The adult male European bison weighs in the range of 800 to 2,000 pounds (400 to 920 kilograms); the female weighs from 650 to 1,200 pounds (300 to 540 kilograms). A good-sized male has a shoulder height of about 6 to 6.5 feet (1.8 to 2 meters) and his body is about 9 feet (2.75 meters) long. The head is very big, and both males and females have horns.

European bison are varying shades of brown, and they have long hair growing from their necks and foreheads and a short beard on their chins. They have a shoulder hump and carry their heads high. In winter, they grow an extra coat of fur to protect themselves from the cold.

Wild Water Buffalo

Wild Water Buffalo
Wild Water Buffalo

The wild water buffalo, also known as the Asian or Indian buffalo, is a very large animal, averaging 7.75 to 10 feet (2.4 to 3 meters) long. It stands 5 to 6.25 feet (1.5 to 2 meters) tall at its shoulder and weighs between 1,550 and 2,650 pounds (700 and 1,200 kilograms). Long, coarse hair covers the buffalo’s ash gray to black body.

Both male and female water buffalo have small ears, thin faces, and widely spread horns. The horns, thick where they emerge from the animal’s head, form a semicircle by curving out and back. Ending in a point, these horns may reach a length of 6 feet (2 meters).

The wild water buffalo’s diet consists of grasses and other vegetation that grows along the shores of lakes and rivers. Although the animal is fast and aggressive, it can fall prey to tigers.

Bactrian Camel

Bactrian Camel
Bactrian Camel

The bactrian camel and the better–known Arabian camel (Camelus dromedarius) are the only two living species of true camel. Whereas the Arabian camel has only one hump, the bactrian camel has two.

An average bactrian camel stands 6 to 7.5 feet (1.8 to 2.3 meters) in height and weighs between 1,000 and 1,575 pounds (455 and 715 kilograms). The coat of a wild bactrian camel is short and gray-brown in color; that of a domestic or tame version of the animal is long and dark brown.

The bactrian camel is well adapted to its desert habitat. Its special eyelids help wipe sand from the surface of the animal’s eye. Its nostrils close to slits to keep out blowing sand. Its broad, thick-soled feet allow it to move steadily and quickly over shifting sand, achieving speeds up to 40 miles per hour (64 kilometers per hour).

Cheetah

Cheetah
Cheetah

“Cheetah” comes from the Hindu word chita, meaning “spotted one.” Round black spots cover the cheetah’s tawny fur and a black streak runs down each cheek. An average cheetah measures 4.5 to 5 feet (1.4 to 1.5 meters) long and stands between 27 and 34 inches (69 and 86 centimeters) high at its shoulder. Its tail extends 24 to 32 inches (61 to 81 centimeters). It weighs between 80 and 145 pounds (36 and 66 kilograms).

Cheetahs are the world’s fastest land animal. They are capable of bursts of speed up to 70 miles per hour (110 kilometers per hour), but they usually cannot keep up this top speed for more than 1500 feet (455 meters).

Unlike other cats, a cheetah cannot retract its claws. This physical feature allows the animal to dig into the ground as it runs, giving it speed. Whereas leopards and tigers ambush their prey, cheetahs chase their prey down.

Chimpanzee

Chimpanzee
Chimpanzee

Chimpanzees, gorillas, and orangutans are all considered great apes. Of the three, chimpanzees are the most closely related to humans. Chimpanzees and humans share 98 percent of the same genetic makeup.

In addition, the two groups share many social and psychological traits. Researchers have documented chimpanzees making and using tools, expressing complex emotions, forming bonds and friendships, and communicating using sign language.

An average chimpanzee stands 5 feet (1.5 meters) tall and weighs about 150 pounds (68 kilograms). Since its arms are longer than its legs, a chimpanzee walks on the ground using the soles of its feet and the knuckles of its hands.

Short-tailed Chinchilla

Short-tailed Chinchilla
Short-tailed Chinchilla

The short-tailed chinchilla is a nocturnal (active at night) rodent with soft fur, large ears, and a bushy tail. It is one of two species of chinchilla—the other is the long-tailed chinchilla (Chinchilla langiera).

An average chinchilla has a head and body length between 9 and 15 inches (23 and 38 centimeters) and a tail length between 3 and 6 inches (7.5 and 15 centimeters).

Female chinchillas weigh up to 28 ounces (794 grams), while the smaller males weigh up to 18 ounces (510 grams). A chinchilla’s silky fur is mostly gray in color. The animal’s hind legs are much larger than its front legs, making it an agile jumper.

Malabar Large Spotted Civet

Malabar Large Spotted Civet
Malabar Large Spotted Civet

The Malabar large spotted civet is nearly identical to, or is in fact the same species as, the large spotted civet (Viverra megaspila). Adults of this species usually weigh about 18 to 20 pounds (8 to 9 kilograms).

Their long gray coats are mottled with large black spots. They have long tails banded in black and a black crest of long fur down their backs. Although most civets look like cats, the Malabar large spotted civet more closely resembles a dog with its long legs and dog-like head.

Malabar civets stay hidden in the thickets during the day and forage for food at night. They have never been seen in trees, and probably obtain their food on the ground. They are thought to eat eggs, small mammals, and some vegetation.

Musk Deer

Musk Deer
Musk Deer

Musk deer are so-named because the males of the species have a gland, called the pod, that develops in the skin of their abdomen. This gland produces a waxy substance called musk, which may be used by males to attract females.

An average musk deer has a head and body length of 28 to 39 inches (71 to 99 centimeters), stands 20 to 24 inches (51 to 91 centimeters) at its shoulder, and weighs between 15 and 40 pounds (7 and 18 kilograms). The musk deer’s hair is long and coarse. It varies in color from dark to golden brown, depending on the species.

The hind legs of a musk deer are almost one-third larger than its front legs. This helps to make the animal a quick and agile jumper. Unlike most other deer, musk deer have no antlers.

Swamp Deer

Swamp Deer
Swamp Deer

The swamp deer is a large member of the deer family. The animal has an average head and body length of 4 to 6 feet (1.2 to 1.8 meters), measures about 4 feet (1.2 meters) in height at its shoulder, and weighs between 375 and 620 pounds (170 and 280 kilograms).

In winter, the swamp deer’s coat is brown on the top part of its body and paler on its underside. In summer, the entire coat lightens in color. Male swamp deer are often darker overall than females. Swamp deer feed on grasses and aquatic plants, and their main predators are tigers and leopards.

In central India, swamp deer are known as barasingha, which means six-pointer. However, their 36- to 40-inch (91- to 102-centimeter) antlers can have 10 or more points. Antlers are solid, bony outgrowths of a deer’s skull. The stem of an antler is called the beam, while the branches are called the tines. Most male deer grow and shed antlers annually.

African Wild Dog

African Wild Dog
African Wild Dog

The African wild dog, also called the African painted wolf, has a streaked, multicolored coat. The tan, black, and white pattern varies between individual dogs, but each animal’s head is usually dark. An African wild dog has large rounded ears, which it uses to signal other dogs and to control body temperature by radiating (giving off) heat. Its 12- to 16-inch (30- to 41-centimeter) tail ends in a plume that is white-tipped.

The dog’s legs are long and thin. An average African wild dog has a head and body length of 30 to 44 inches (76 to 112 centimeters) and a shoulder height of 24 to 31 inches (61 to 79 centimeters). It weighs between 37 and 79 pounds (17 and 36 kilograms).

African wild dogs have a tightly knit social structure. They form packs of 2 to 45 members that hunt cooperatively. Prey includes impalas, antelopes, gazelles, zebras, wildebeest, and warthogs.

Chinese River Dolphin

Chinese River Dolphin
Chinese River Dolphin

The Chinese river dolphin, also known as baiji, is one of the most rare and endangered cetaceans (pronounced si–TAY–shuns; the order of aquatic mammals that includes whales, dolphins, and porpoises). It has an average overall length of 6.75 to 8.25 feet (2 to 2.5 meters) and weighs between 220 and 500 pounds (100 and 230 kilograms). Its body color is blue-gray on top and almost white underneath.

Chinese river dolphins have very poor eyesight, which is an evolutionary result of the muddy conditions of the water in which they live. Since the dolphins could not use their vision, they lost it over the course of time.

The species adapted to this loss by developing the ability to use echolocation (sonar). In this process, the dolphin emits a sound wave that bounces off objects and is echoed or reflected back to the dolphin. Like bats, Chinese river dolphins use echolocation to navigate and to find prey.

Dugong

Dugong
Dugong

Dugongs are very large sea mammals, sometimes called “sea cows.” They have been familiar to humans for centuries, particularly because, for some reason, these ungainly creatures gave rise to the mermaid myths of the past.

Adult dugongs, both male and female, range in size from 8 to 13 feet (2.4 to 4 meters). They weigh between 500 and 1,100 pounds (230 to 500 kilograms) and have a big roll of fat around their bodies. Dugongs are gray or rusty brown in color; their young, called calves, are born a creamy beige and then darken as they grow.

Although dugongs breathe air into their lungs like land mammals, they live in the ocean and never come onto land. They are able to stay underwater for up to about six minutes at a time, but their dives usually last only one to three minutes before they come up for air.

African Elephant

African Elephant

The African elephant is the world’s largest living land mammal. An average adult male stands 10 feet (3 meters) tall at its shoulder and weighs between 11,000 and 13,000 pounds (5,000 and 5,900 kilograms). Females are a little shorter in height and weigh about 8,000 pounds (3,600 kilograms).

The animal’s thick and loose skin is dark, muddy gray in color. Its large ears, up to 42 inches (107 centimeters) in diameter, hold many prominent veins. To cool its blood during the heat of the day, the African elephant flaps its ears vigorously.

Its long, white tusks are actually elongated incisor teeth. It has only four other teeth, all molars, that it uses to grind down food. These teeth are replaced up to six times as they wear away periodically during an average elephant’s seventy-year life span.

Asian Elephant


Description and biology

The Asian elephant, also known as the Indian elephant, is smaller than its relative, the African elephant. An average male Asian elephant weighs up to 11,500 pounds (5,220 kilograms) and stands 8.5 feet (2.6 meters) tall at its shoulder.

Females of the species are slightly shorter in height and weigh up to 6,000 pounds (2,270 kilograms). The elephant has an arched back and a flat forehead. Its ears are smaller and its trunk shorter and smoother than those of the African elephant.

The Asian elephant’s trunk, which is an extension of its nose and upper lip, has one finger like tip at the end that is used to grasp food and other items. Elephants also use their trunks for drinking, bathing, smelling, breathing, feeling, greeting, and communicating. All of the animals can create a variety of sounds with their trunks, from rumbling noises to the well–known trumpeting sound.

Black Footed Ferret

Black Footed Ferret
Black Footed Ferret

Description and biology

The black–footed ferret is a member of the weasel family (other members include weasels, martens, fishers, otters, minks, wolverines, and skunks). Similar in size to a mink, the back–footed ferret has a long, slender body covered in short, pale yellow fur.

On its throat and belly, the fur is nearly white. The animal has a brownish head, a brownish–black mask across its eyes, black feet and legs, and a black tip on its tail.

An average black–footed ferret has a body length of 18 to 22 inches (46 to 59 centimeters) and a tail length of 4.5 to 5.5 inches (11.5 to 14 centimeters). It weighs 18 to 36 ounces (510 to 1,021 grams).

Island Gray Fox

Island Gray Fox
Island Gray Fox

Description and biology

While the island gray fox is mostly gray, its belly and throat are white, and the sides of its neck and the underside of its tail are rust. Black markings often accent its face and limbs.

An average island gray fox has a head and body length of 20 inches (50 centimeters) and stands roughly 5 inches (13 centimeters) tall at its shoulder. Its tail can extend in length from 4.5 to 11.5 inches (11.4 to 29.2 centimeters). It weighs between 3 and 6 pounds (1.3 and 2.7 kilograms).

The island gray fox hunts for food primarily in the early morning and late evening. Insects and fruits constitute the main portion of its diet, with small mammals, birds, reptiles, and eggs making up the remainder.

Dama Gazelle

Dama Gazelle
Dama Gazelle

Description and biology

The dama gazelle, a graceful antelope found in the Sahara Desert region of Africa, has long legs, a long neck, and ringed horns curved back in the shape of a lyre (musical instrument). Its neck and a portion of its back are reddish brown in color, while the rest of its body is white (including one spot on the inside of its neck).

An average dama gazelle has a head and body length of 40 to 67 inches (102 to 170 centimeters) and measures 35 to 42 inches (89 and 107 centimeters) high at its shoulder. Its tail, white with a black tip, extends 9 to 12 inches (23 to 30 centimeters). The animal weighs between 90 and 185 pounds (41 and 84 kilograms).

Like most species of gazelle, the dama gazelle has keen senses of hearing and smell. It grazes on shrubs and trees such as acacia and desert date. This gazelle travels alone or in small groups in search of food. A female dama gazelle gives birth usually to one infant after a gestation (pregnancy) period of 160 to 220 days.

Hoolock Gibbon

Hoolock Gibbon
Hoolock Gibbon

Description and biology

Gibbons are apes, related to gorillas and chimpanzees, but they are known as “lesser apes” because of their small size. There are 13 or more kinds of gibbons. Hoolock gibbons are the second–largest kind, generally growing to about 13 pounds (6 kilograms).

Adults are about 24 to 35 inches (60 to 90 centimeters) long and have no tail. Male hoolocks have black fur with white eyebrows, while females have beige or red–brown fur with dark brown eyebrows and cheek areas.

Gibbons are amazing acrobats when it comes to brachiating, or swinging by their arms among the treetops. Hoolocks’ bodies are built for this movement. They have very long arms and long, hook–shaped hands.


They swing by their arms from one branch to another, with their hand forming a hook on the limb. They are capable of leaping long distances through the air from branch to branch or running atop the leaves in the treetops. Their diet is made up mainly of fruit and leaves, along with some insects and flowers.

Figs are a favorite food. Hoolocks are diurnal, meaning they roam the forests during the day and sleep at night. A family of hoolocks generally sleeps sitting up in one or two favored treetops. When they need to come down from the trees, hoolocks walk on two feet in an upright position.

Most gibbons live in family units consisting of two parents with several immature offspring. They are monogamous (when the male and female become partners, they remain together for life).

Gibbons generally give birth to one offspring at a time. Baby hoolock gibbons are born with no hair and depend upon their mothers for warmth. The offspring usually stay with their parents until they are six to nine years old and have reached sexual maturity.

Each gibbon family group lives within its own specific territory, usually about 30 to 50 acres (12 to 20 hectares) in area, which they defend from the intrusion of other gibbons. The life span of a gibbon in the wild is not known, but is probably about 30 to 40 years.

Hoolocks, like other gibbons, are very musical mammals, with a distinctive form of vocal communication displayed in half–hour–long morning songs performed by the family each day.

The male and female partners sing a kind of duet together, and then other members of the family may join in to sing solos. These morning songs communicate to other gibbons that the hoolock family’s area is claimed and will be defended, and may also serve as mating calls from the younger family members.

The folklore of the indigenous (native) people of Southeast Asia includes many stories about this magical music of the rain forests. Unfortunately, these morning songs also inform hunters of the location of the gibbon families.

The only known enemy to hoolock gibbons is the human being.

Habitat and current distribution

Gibbons have lived in the forests of Southeast Asia for millions of years. The hoolock is found in tropical (a climate warm enough year–round to sustain plant life) and subtropical evergreen forests, and in mountain forests produced by seasonal monsoons (heavy rainfalls accompanying high winds).

Curently hoolocks live in Myanmar (formerly Burma), Bangladesh, the northeastern part of India, and the southwestern part of China. There are two subspecies of hoolock gibbons, the eastern and western. They are divided by the Chindwin River in Myanmar. Hoolocks range from the Brahmaputra River (in Bangladesh, India, and China) on the west to the Salween River (in China and Myanmar) on the east.

History and conservation measures

The habitat in which hoolock gibbons live is shrinking rapidly. The tropical and subtropical forests are being cut down and burned in order to make way for tea plantations and other crops, for logging and taking out other fuel, and also for human settlement.

As their habitat is fragmented by the clearing of forests, hoolock gibbons become more vulnerable to humans, since they must come down from the treetops to cross from one food source to the next.

Humans hunt hoolocks for food and to sell as pets, and gibbon bones and meat are valued in some traditional Asian medicines. Among some groups in Myanmar, for example, it is believed that eating the dried hands and legs of hoolocks will promote fertility (the ability to have children) in women.

In 1977, biologists (scientists who study living organisms) estimated the hoolock gibbon population at more than 500,000 animals. Ten years later, it was down to 170,000.

By 2000, the hoolock gibbon population had been severely reduced. In India (where there were about 80,000 hoolocks in the early 1970s), there were only about 5,000 animals in 2000; there were less than 200 hoolocks in China, and 200 in Bangladesh. There is no current data about hoolock gibbons in Myanmar.

Preserving the remaining rain forest habitat and eliminating hunting of hoolock gibbons are key factors in the effort to save the species from extinction in the wild. Since the 1990s, some sanctuaries and reserves have been created within hoolock gibbon habitats.

China and India have laws protecting gibbons, but the enforcement is not strict and poachers (illegal hunters) continue to profit from killing hoolocks in the wild.

Gorilla

Gorilla
Gorilla

Description and biology

The gorilla is considered the most intelligent land animal other than humans. It is the largest of the living primates, an order of mammals that includes lemurs, monkeys, chimpanzees, orangutans, and human beings. When standing on its hind legs, an average male gorilla measures 5 to 5.75 feet (1.5 to 1.75 meters) high.

It can weigh between 300 and 500 pounds (136 and 227 kilograms). Females are smaller, measuring about 5 feet (1.5 meters) in height and weighing between 200 and 250 pounds (91 and 114 kilograms). The color of a gorilla’s coat varies from brown–gray to black.

In males, the hair on the back begins to turn silver after 10 years of age. Males also have a large bone on top of their skull (called the sagittal crest) that supports their massive jaw muscles and gives them their distinctive high forehead. Both sexes have small ears, broad nostrils, and a black, hairless face.

Pygmy Hippopotamus

Pygmy Hippopotamus
Pygmy Hippopotamus

Description and biology

The pygmy hippopotamus is smaller and more piglike in appearance than its larger relative, the common hippopotamus. Its skin color is generally black, with a greenish tinge on the top of its back. Its belly is cream or yellow–gray.

Its eyes are on the side of its round head instead of on top as in the common hippo. An average pygmy hippo has a head and body length of 5 to 5.5 feet (1.5 to 1.7 meters) and a shoulder height of 30 to 39 inches (76 to 99 centimeters).

Its tail extends 6 inches (15 centimeters). It weighs between 355 and 600 pounds (161 and 272 kilograms). By contrast, an average common hippo weighs between 2,425 and 5,720 pounds (1,100 and 2,597 kilograms).

The pygmy hippo is a solitary animal, spending much of its time on the shore near swamps and rivers. It goes in the water only occasionally. Like the common hippo, the pygmy hippo has glands beneath its skin that secrete a pink, sweat–like substance.

This biological fact has inspired the myth that hippos “sweat blood.” This pink substance helps to regulate the hippo’s skin temperature. Because its skin is sensitive to the sun, the pygmy hippo seeks shelter during the day in thickets and other forested areas.

It feeds at night on leaves, shoots, grasses, roots, and fruits. Male and female pygmy hippos usually mate in the water at any time during the year. After a gestation (pregnancy) period of 188 days, a female pygmy hippo gives birth to one calf. She then nurses that calf for eight months.

Habitat and current distribution

Pygmy hippos inhabit lowland forests. They are found in the tropical region of western Africa, primarily in the country of Liberia. Wildlife biologists (people who study living organisms) estimated that the pygmy hippo population in Liberia in the early 1980s was several thousand. No estimates have been made since then, but the population has almost certainly decreased.

History and conservation measures

Deforestation and hunting are the major threats to pygmy hippopotami. Africans hunt the animal and its larger relative for their meat and hides, which are used to make whips and shields. Very few conservation efforts exist for the pygmy hippopotamus. Between 350 and 400 pygmy hippos are held in captivity throughout the world.

Pygmy Hog

Pygmy Hog
Pygmy Hog

Description and biology

The pygmy hog is the smallest of all pig species. An average adult pygmy hog is 25 inches (63.5 centimeters) long, stands 10 inches (25 centimeters) tall at its shoulder, and weighs 19 pounds (8.6 kilograms).

Its short tail measures only 1 inch (2.5 centimeters). Its hide is covered with coarse dark brown or black bristles. Because of its small, bullet–like shape, the animal is extremely agile.

Male pygmy hogs are larger than their female counterparts and have exposed tusks. The normally solitary males interact with the females only during mating season. A female pygmy hog gives birth to a litter of two to six infants, usually in late April or May, after a gestation (pregnancy) period of about 100 days. Both males and females build and use their nests throughout the year.

Przewalski’s Horse

Przewalski’s Horse
Przewalski’s Horse

Description and biology

Przewalski’s horse is the last truly wild horse. Slightly smaller than most domestic horses, it has a compact body with a thick neck and large head. The color of its upper body is dun (a dull grayish brown), while its belly and muzzle are much lighter.

The horse has a dark stripe along its backbone and a dark, plumed tail. The dark hair on its head and along its neck (the mane) is short and stands erect. Unlike the domestic horse, Przewalski’s horse sheds its mane and the short hairs at the base of its tail annually.

An average Przewalski’s horse may reach 8 feet (2.4 meters) in length and stand 4 to 4.5 feet (1.2 to 1.4 meters) high at its shoulders. It may vary in weight between 440 and 750 pounds (200 and 340 kilograms). The horse feeds primarily on grass and other low vegetation.


Groups of Przewalski’s horses are headed by a dominant stallion (male), which is responsible for breeding with most of the group’s females. The females usually give birth to a single foal (infant) between April and June, after a gestation (pregnancy) period of 330 to 340 days. The foals may nurse for up to two years.

Habitat and current distribution

Przewalski’s horses prefer open grassland, steppe (vast, semiarid grass–covered plain), and semidesert areas. The last possible sighting of Przewalski’s horse in the wild was in 1968.

Chinese biologists (people who study living organisms) believe there may be a small population of horses inhabiting northeastern Xingiang (an autonomous region in northwestern China). It is more likely that this group is extinct.

Over 1,000 Przewalski’s horses are currently held in captivity in zoos and reserves around the world.

History and conservation measures

Przewalski’s horse was discovered in 1878 by Russian geographer and explorer Nikolai Mikhailovich Przhevalsky (1839–1888). Scientists believe the horse once ranged from western Mongolia to northern Xingiang and western Kazakhstan.

By 1900, hunting and competition with domestic horses for food and water greatly reduced the Przewalski’s horse population. By the 1950s, the remaining animals were seen in a small area between southwestern Mongolia and northwestern China called the Takhin–Shara–Nuru (mountain of the yellow horses). The Przewalski’s horse was last seen in the wild in 1968.

The International Union for Conservation of Nature and Natural Resources (IUCN) listed the species as extinct in the wild in 1996. However, the Przewalski’s horse has become a great success story in the ongoing efforts to preserve species through reintroduction to the wild.

In 1992, 16 horses bred in captivity and chosen for their genetic (inherited) traits were slowly and carefully reintroduced to the wilderness at Hustai National Park in Mongolia. By 2000, 84 horses had been reintroduced and 114 foals had been born in the wild.

In the early 2000s, a population of around 142 Przewalski’s horses roamed freely in the park, and the animals appeared to be doing better each year they spend in the wild. They are being very carefully watched and protected as they adapt to the original habitat of the species.

Brown Hyena

Brown Hyena
Brown Hyena

Description and biology

The brown hyena, also known as the strand wolf, has a long, brown, shaggy coat with lighter underparts. Its face and legs are gray to black. An average brown hyena measures 43 to 53 inches (109 to 135 centimeters) long and stands 25 to 35 inches (64 to 89 centimeters) high at its shoulder. It weighs between 82 and 104 pounds (37 and 47 kilograms). Males are larger than females.

The brown hyena feeds primarily on the remains of prey killed by other predators. With its strong teeth and jaws, the animal can crush and eat bone. It also feeds on insects, eggs, fruits, and an occasional small animal or bird that it kills. Although it has acute vision and hearing, the brown hyena locates its prey by scent. Lions and spotted hyenas are the animal’s main predators.

Brown hyenas sleep during the day and hunt at dusk or during the night. While on its nightly hunting expedition, a brown hyena will normally cover about 19 square miles (49 square kilometers). Some have been known to travel over 31 square miles (80 square kilometers).


Although often solitary in their habits, brown hyenas will form clans of up to 10 members. Male and female brown hyenas mate at any time during the year. After a gestation (pregnancy) period of 90 to 100 days, a female will give birth to 1 to 5 cubs.

In a communal den (dwelling place shared by all members in a clan), cubs may suckle from females other than their mother. All members of the clan help to feed the cubs by carrying food to the den.

Habitat and current distribution

In southern Africa, brown hyenas inhabit arid (dry) areas such as rocky deserts with thick brush, open grassland and scrub (land covered with stunted trees and shrubs), and semideserts. They sleep in dense vegetation, under sheltering rocks, or in burrows dug by other animals.

History and conservation measures

Scientists do not know the exact number of existing brown hyenas, but they believe the animals’ range and population has been greatly reduced. Of the six African countries where brown hyenas can be found, only Botswana and Zimbabwe host sizable populations.

Many humans dislike brown hyenas because of their foul stench and their cry (which sounds like maniacal laughter). Brown hyenas are often killed by humans for these reasons and because the animals are seen as a threat to livestock. Since brown hyenas feed on carrion (decaying flesh of dead animals), this last view is utterly false.

Brown hyenas are given protection in several conservation areas in the Kalahari, an arid plateau region stretching about 100,000 square miles (259,000 square kilometers) in Botswana, Namibia, and South Africa. The animals are also protected along the coastal regions of the southern Namib Desert in western Namibia.