An alligator is a crocodilian in the genus Alligator of the family Alligatoridae. There are two living alligator species: the American alligator (Alligator mississippiensis) and the Chinese alligator (Alligator sinensis). They are closely related to crocodiles.
Alligators are characterized by a broader snout and eyes more dorsally located than their crocodile cousins. Both living species also tend to be darker in color, often nearly black (although the Chinese alligator has some light patterning.) Also, in alligators only the upper teeth can be seen with the jaws closed (in contrast to true crocodiles, in which upper and lower teeth can be seen), though many individuals bear jaw deformities which complicate this means of identification.
There are only two countries on earth that have alligators: the United States and China. The Chinese alligator is endangered and lives only in the Yangtze River valley. The American alligator is found in the United States from the Carolinas to Florida and along the Gulf Coast. The majority of American alligators inhabit Florida and Louisiana. In Florida alone there are an estimated more than 1 million alligators. The United States is the only nation on earth to have both alligators and crocodiles. American alligators live in freshwater environments, such as ponds, marshes, wetlands, rivers, and swamps. In China, they live only along the fresh water of the Yangtze River.
Alligators are solitary, territorial animals. The largest of the species (both males and females) will defend prime territory; smaller alligators have a higher tolerance of other alligators within a similar size class. Although alligators have heavy bodies and slow metabolisms, they are capable of short bursts of speed that can exceed 30 miles per hour. Alligators' main prey are smaller animals that they can kill and eat with a single bite. Alligators may kill larger prey by grabbing it and dragging it in the water to drown. Alligators consume food that cannot be eaten in one bite by allowing it to rot or by biting and then spinning or convulsing wildly until bite size pieces are torn off. This is referred to as the "death roll."
Alligators are opportunistic feeders, eating almost anything they can catch. When they are young they eat fish, insects, snails and crustaceans. As they grow they take progressively larger prey items, including: larger fish such as gar, turtles, various mammals, birds, and other reptiles, including smaller alligators. They will even consume carrion if they are sufficiently hungry. As humans encroach onto to their habitat, attacks on humans are not unknown, but are few and far between.
The American alligator, Alligator mississipiensis, is found in swamps and sluggish streams from North Carolina to Florida and along the Gulf Coast. When young, it is dark brown or black with yellow transverse bands. The bands fade as the animal grows, and the adult is black. Males commonly reach a length of 9 feet and a weight of 250 lbs; females are smaller. Males 18 feet long were once fairly common, but intensive hunting for alligator leather eliminated larger individuals and threatened the species as a whole. The wild American alligator is now protected by law, but it is also inhumanely raised on farms for commercial uses.
The Chinese alligator, A. sinensis, which grows to about 6 feet long, is found in the Chang (Yangtze) River valley near Shanghai. This species is nearly extinct.
Alligators spend the day floating just below the surface of the water or resting on the bank, lying in holes in hot weather. They hunt by night, in the water and on the bank. Alligators hibernate from October to March. In summer the female builds a nest of rotting vegetation on the bank and deposits in it 20 to 70 eggs. The mother will defend the nest from predators and will assist the babies to water once they hatch. She will provide protection to the young for about a year if they remain in the area.
Caimans are similar to alligators, but distinct members of the Alligatoridae family found in Central and South America. There are several species, classified in three genera. The largest grow up to 15 feet long. Unlike alligators, caimans have bony overlapping scales on their bellies. Baby caimans are often sold in the United States as baby alligators. Caimans and alligators are wild animals and should not be kept as pets for human amusement.
Alligators and caimans are classified in the phylum Chordata, subphylum Vertebrata, class Reptilia, order Crocodilia, family Alligatoridae.
THREATS TO ALLIGATORS
American alligator populations were decimated by decades of hunting and habitat loss. In 1967 the animal was added to the federal endangered species list. The alligator recovered dramatically and was removed from the endangered species list in 1987. Alligators still face threats today, primarily from loss and fragmentation of natural habitats and encounters with people.
The Chinese alligator's population reduction has been mostly due to conversion of its habitat to agricultural use. A majority of their usual wetland habitats has been turned into rice paddies. Poisoning of rats, which the alligators then eat, has also been blamed for their decline. It was also not uncommon for people to kill the alligators, because they believed they were pests, out of fear, or for their meat. In the past decade, very few wild nests have been found, and even fewer produced viable offspring.
Collection for the exotic pet trade affects alligators. Every year, a variety of sources provides millions of animals to the exotic pet trade. Animals are captured from their native habitat and transported to various countries to be sold as “pets”. Others are surplus animals from zoos or their offspring. Backyard breeders also supply exotic animals. The sellers of these animals often disregard state or local laws regulating private possession of exotics, and the dangers, difficulties, physical and physiological needs of the animals they peddle. The suffering of the animals in the hands of unqualified and hapless buyers appears to be of no concern in the lucrative exotic pet trade. Reptiles pose safety risks to humans. Many incidents have been reported of escapes, strangulations, and bites from pet reptiles across the country.
Alligators are also victims of the animal entertainment industry. The use of wild animals as “entertainers” removes animals from their natural habitat; depriving them of the ability to freely engage in instinctual behaviors. Both children and adults are desensitized to animal mistreatment by the animal entertainment industry. Even under the best of circumstances, captivity is cruel for wild animals. Confined to tiny areas and gawked at by crowds, animals in exhibits and acts endure constant stress. They may suffer from temperature extremes and irregular feeding and watering. Without exercise, they become listless, their immune systems are weakened, and they become prone to sickness; many resort to self-mutilation in reaction to stress or boredom. Mental illness is rampant among confined animals. Torn from their families and deprived of all dignity, every part of their lives is controlled by their captors. While zoos may appear to be educational and conservation-oriented, most are designed with the needs and desires of the visitors in mind, not the needs of the animals.
Alligators also are inhumanely farmed commercially. Their hide is tanned and used to make leather goods such as shoes and handbags, while alligator meat is also considered a delicacy in many parts of the world.
Sparrows are small birds found around the globe. Originating from Europe, Northern Africa and Asia, human travelers introduced sparrows to almost every continent. Sparrows prefer to live close to human settlements, including rural and urban areas. There are around 140 species of sparrow.
Sparrows are very small and have stout bodies covered with black, brown and white feathers. Their wings are rounded. Sparrows have smooth, rounded heads. Male sparrows have reddish backs and black bibs. Female sparrows have brown backs with stripes.
Sparrows can fly fast and can swim quickly to escape predators. They can even swim under water. Sparrows often hop around instead of walking. They bathe in dust.
Sparrows are omnivores, feeding on seeds, fruit and insects. They are known for adjusting their eating habits based on food sources provided by humans. They are frequent visitors to bird feeders. Sparrows usually forage for food on the ground.
Sparrows are very social birds. They live in colonies, called flocks, and fly together. While not usually territorial birds, sparrows will aggressively protect their nests from other sparrows and other animals.
Sparrows are usually non-migratory, but urban flocks may move to the countryside in the late summer to feed on grains.
Sparrows are extremely vocal birds that chirp all the time. Sparrows use song to attract mates and announce their territory. Female sparrows are attracted not just to the male sparrow's song, but also to how well it reflects his ability to learn. Males that utilize more learned components in their songs, and that better match the adult bird they learned their songs from, are preferred by the females. Sparrows also use a set of postures and behaviors to communicate with other.
Sparrow mating season occurs in the spring. Sparrows were once thought to be monogamous, but most sparrows have sex with multiple partners. Sparrows construct nests in trees, shrubs and man-made structures. Male sparrows often build the nest while attempting to attract females. Interested females then help in the construction. Sometimes sparrows take over nests of other bird species. Female sparrows lay 4 to 5 eggs per clutch, having several broods each year. Mother sparrows incubate the eggs for a couple of weeks. Both the female and the male may take care of the babies until they are strong enough to leave the nest, usually in about 15 days.
Being small birds, sparrows have numerous predators including dogs, cats, foxes, snakes and birds of prey.
Sparrows live up to 13 years in the wild.
THREATS TO SPARROWS
Sparrow populations have decreased dramatically due to irresponsible human activities. Some sparrows are now listed as threatened, nearly endangered. Sparrows are threatened by modern agricultural practices, pollution, pesticides, predators and a reduced amount of gardens. Some sparrows are losing their main food sources and are struggling to survive winters.
One of 30 cougar subspecies, the Florida panther is an endangered species. Panthers are tawny brown on the back and pale gray underneath, with white flecks on the head, neck and shoulder. Males weigh up to 130 pounds; females 70 pounds. Panthers live in cypress swamps and pine and hardwood hammock forests.
Originally from western Texas and found throughout the southeastern states; they are now only in Florida. Panthers feed mostly on white-tailed deer, wild hogs, rabbits, raccoons, armadillos and birds. They are solitary, territorial and often travel at night. Males have a home range of up to 400 square miles and females about 50 to 100 square miles.
Panthers reach sexual maturity at about 3 years. Mating season is December through February. Gestation lasts about 90 days and females bear 2-6 kittens. Young stay with the mother for about two years. Females do not mate again until the young have left.
THREATS TO PANTHERS
Threats to panthers include habitat loss because of human development, collision with vehicles, parasites, feline distemper, feline calicivirus (an upper respiratory infection) and other diseases. The biggest threat to their survival is human encroachment. Historical persecution reduced this wide-ranging, large carnivore to a small area of south Florida. This created a tiny isolated population that became inbred.
Reduced speeding zones, construction of panther underpasses, public education, captive breeding programs and research are efforts being taken to save the Florida panther from extinction.
The black panther is the common name for a black specimen (a genetic variant) of several species of cats. Zoologically, a panther is the same as a leopard, while the term Panthera describes the whole family of big cats. But, in North America, the term panther is also used for puma. In South America it could also mean a jaguar. Elsewhere in the world it refers to leopard.
It does not exist as a separate species. The genetic variant is most common in jaguars (Panthera onca) where it is due to a dominant gene mutation, and leopards (Panthera pardus) where it is due to a recessive gene mutation. Close examination of one of these black cats will show that the typical markings are still there, and are simply hidden by the surplus of the black pigment melanin. Cats with melanism can coexist with litter mates that do not have this condition. In cats that hunt mainly at night, the condition is not detrimental. White panthers also exist, these being albino or leucistic individuals of the same three species.
It is probable that melanism is a favorable evolutionary mutation with a selective advantage under certain conditions for its possessor, since it is more commonly found in regions of dense forest, where light levels are lower. Melanism can also be linked to beneficial mutations in the immune system.
In jaguars, the mutation is dominant hence black jaguars can produce both black and spotted cubs, but spotted jaguars only produce spotted cubs when bred together. In leopards, the mutation is recessive and some spotted leopards can produce black cubs (if both parents carry the gene in hidden form) while black leopards always breed true when mated together. The black jaguar was considered a separate species by indigenous peoples.
Black leopards are the most common form of black panther in captivity and have been selectively bred for decades as exhibits or exotic pets. This inhumane inbreeding for the sake of appearance has adversely affected temperament. They are smaller and more lightly built than jaguars. The spotted pattern is still visible on black leopards.
It is a myth that their mothers often reject them at a young age because of their color. In actuality, they are more temperamental because they have been inbred (e.g. brother/sister, father/daughter, mother/son matings) to preserve the coloration. The poor temperament has been bred into the strain as a side effect of inbreeding. It is this poor temperament that leads to problems of maternal care in captivity as the proximity of humans stresses the mother.
Black leopards are reported from moist densely forested areas in south western China, Burma, Assam and Nepal; from Travancore and other parts of southern India and are said to be common in Java and the southern part of the Malay Peninsula where they may be more numerous than spotted leopards. They are less common in tropical Africa, but have been reported from Ethiopia (formerly Abyssinia), the forests of Mount Kenya and the Aberdares. One was recorded in the equatorial forest of Cameroon.
Eagle, common name for large predatory birds of the family Falconidae (hawk family), are found in all parts of the world. Eagles are similar to the buteos, or buzzard hawks, but are larger both in length and in wingspread (up to 7 1⁄2 feet) and have beaks nearly as long as their heads.
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh. In most cases, the females are considerably larger than the males. Because of their predatory lifestyle, often at the top of the food chain, they face distinct conservation concerns.
Eagles differ from many other birds of prey mainly by their larger size, more powerful build, and heavier head and beak. Even the smallest eagles, like the booted eagle, have relatively longer and more evenly broad wings, and more direct, faster flight. Most eagles are larger than any other raptors apart from the vultures. Species named as eagles range in size from the South Nicobar serpent eagle, at 1.1 lb and 16 inches, to the 14.7 lb Steller's sea eagle and the 39 inch Philippine eagle. Like all birds of prey, eagles have very large hooked beaks for tearing flesh from their prey, strong muscular legs, and powerful talons. They also have extremely keen eyesight which enables them to spot potential prey from a very long distance. This keen eyesight is primarily contributed by their extremely large pupils which ensure minimal diffraction (scattering) of the incoming light.
Eagles build their nests, called eyries, in tall trees or on high cliffs. Many species lay two eggs, but the older, larger chick frequently kills its younger sibling once it has hatched. The dominant chick tends to be the female, as they are bigger than the male. The parents take no action to stop the killing.
Eagles are solitary birds that mate for life. The nest of twigs and sticks is built at a vantage point high in a tree or on a cliff in a permanent feeding territory and is added to year after year; the refuse of the previous nests decomposing beneath the new additions. Nests can become enormous, measuring up to ten feet across and weighing well over 1,000 pounds. The eaglets do not develop adult markings until their third year, when they leave parental protection and seek their own mates and territories.
The American bald, or white-headed, eagle (Haliaetus leucocephalus) is found in all parts of North America near water and feeds chiefly on dead fish (sometimes robbing the osprey's catch) and rodents. It is dark brown with white head, neck and tail plumage. The northern species (found chiefly in Canada) is slightly larger than the southern, which ranges throughout the United States. With only 417 known breeding pairs in the 48 contiguous states in 1963, the bald eagle population was dwindling alarmingly; a decade later they were placed on the endangered species list. In one of the greatest success stories in species recovery, conservation methods such as the banning of DDT and the prohibition against eagle hunting had by the beginning of the 21st century increased the breeding population in the lower 48 states to some 5,000 pairs. The bald eagle was removed from endangered status in 1995 and is now classified as threatened.
The golden, or mountain, eagle is widespread in the Northern Hemisphere, in the United States found mostly in the West. Unlike the bald eagle, it is an aggressive predator. In Asia it is trained to hunt small game. The adult is sooty brown with tawny head and neck feathers; unlike those of the bald eagle, its legs are feathered to the toes.
The gray and Steller's sea eagles are native to colder areas of the Northern Hemisphere; the king or imperial eagle to South Europe and Asia; and the rare monkey-eating eagle to the Philippines.
The harpy, or harpy eagle, of Central and South America, the largest of the hawks, eats macaws and sloths. It was named for the winged monsters of Greek myth and was called "winged wolf" by the Aztecs.
Eagles - impressive both in size and for their fearsome beauty - have long been symbols of royal power and have appeared on coins, seals, flags, and standards since ancient times. The eagle was the emblem of one of the Ptolemies of Egypt and was worn on the standards of the Roman armies and of Napoleon's troops. The American bald eagle became the national emblem of the United States by act of Congress in 1782. In folklore the eagle's ability to carry off prey, including children, has been exaggerated; even the powerful golden eagle can lift no more than 8 lb.
Eagles are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Falconiformes, family Accipitridae.
THREATS TO EAGLES
Eagles are threatened by habitat loss, pesticides, hunting, poisoning from carcasses of other animals poisoned by humans, wind farms, electrocution from power lines, and lead poisoning from eating ducks that have consumed lead shot.
The American black bear (Ursus americanus), also known as the cinnamon bear, is the most common bear species native to North America. The black bear occurs throughout much of the continent, from northern Canada and Alaska south into Mexico, from the Atlantic to the Pacific. This includes 39 of the 50 U.S. states and all Canadian provinces. Populations in east-central and the southern United States remain in the protected mountains and woodlands of parks and preserves, though bears will occasionally wander outside the parks' boundaries and have setup new territories in recent years in this manner.
While there were probably once as many as two million black bears in North America, the population declined to a low of 200,000 before rebounding in recent decades, partly due to conservation measures. By current estimates, more than 600,000 are living today.
The black bear is about 5 feet long. Females weigh between 90 and 400 pounds, while males weigh between 110 and 880 pounds. Cubs usually weigh between seven ounces and one pound at birth. The adult black bear has small eyes, rounded ears, a long snout, a large body, and a short tail. They have an excellent sense of smell. Though these bears indeed generally have shaggy black hair, the coat can vary in color depending on the subspecies: from white through chocolate brown, cinnamon brown, and blonde, found mostly west of the Mississippi River, to black in the east (the same is generally true in Canada with the border being between Manitoba and Ontario). Further adding to the confusion, black bears occasionally sport a slight white chest blaze on either side of the river.
While black bears are able to stand and walk on their hind legs, they usually stand or walk on all four legs. When they do stand it usually is to get a better look at something. The black bear's characteristic shuffle results from walking flat-footed, with the hind legs slightly longer than the front legs. Each paw has five strong claws used for tearing, digging and climbing. One blow from a powerful front paw is enough to kill an adult elk.
Black bears prefer forested and shrubby areas but use wet meadows, high tidelands, ridgetops, burned areas, riparian areas and avalanche chutes. They also frequent swampy hardwood and conifer forests. After emerging from their winter dens in spring, they seek southerly slopes at lower elevations for forage and move to northerly and easterly slopes at higher elevations as summer progresses. Black bears use dense cover for hiding and thermal protection, as well as for bedding. They climb trees to escape danger and use forested areas as travel corridors. Black bears hibernate during winter and may build dens in tree cavities, under logs, rocks, in banks, caves, or culverts, and in shallow depressions.
Black bears reach breeding maturity at about 4 or 5 years of age, and breed every 2 to 3 years. Black bears breed in the spring, usually in May and June, but the embryos do not begin to develop until the mother dens in the fall to hibernate through the winter months (delayed implantation.) However, if food was scarce and the mother has not gained enough fat to sustain herself during hibernation as well as produce cubs, the embryos do not implant (develop). Black bear cubs are generally born in January or February. They are blind when born, and twins are most common, though up to four cubs is not unheard of and first-time mothers typically have only a single cub. By spring thaw, when the bears start leaving their dens, the cubs are fur-balls of energy, inquisitive and playful.
When their mother senses danger she grunts to the cubs to climb high up a tree. They are weaned between July and September of their first year, and stay with the mother through the first winter. They are usually independent by the second winter. Cub survival is totally dependent on the skill of the mother in teaching her cubs what to eat, where and how to forage (find food), where to den, and when and where to seek shelter from heat or danger.
Black bears are omnivores. They eat a wide variety of foods, relying most heavily on grasses, herbs, fruits and mast. They also feed on carrion and insects such as carpenter ants, yellow jackets, bees and termites. Black bears sometimes kill and eat small rodents and ungulate fawns. Unlike the brown bear, black bears like to attack and eat dead creatures, which makes humans feigning death at bear attacks ineffective. Like many animals, black bears seldom attack unless cornered or threatened. They are less likely to attack man than grizzly bears and typically run for cover before one catches sight of them. Black bear predation on man is extremely rare. It is estimated that there have been only 56 documented killings of humans by black bears in North America in the past 100 years. Black bear predators include other black bears, man, and the grizzly. Coyotes and mountain lions may prey on cubs.
Because their behavior has been little understood until recently, black bears have been feared and hated. Before the 20th century these bears were shot intermittently as vermin, food, and trophies being seen as either a vicious beast or an endless commodity. In many areas bounties were paid, until recently, for black bears. Paradoxically, black bears have also been portrayed as harmless and cuddly. For example, the "teddy bear" owes its existence to a young black bear cub Theodore Roosevelt refused to shoot.
Their tendencies to follow their stomachs and habitat encroachment by man have created human-bear conflicts. This is true especially in areas where they may have been uncommon or absent for a long time, as in many parts of the eastern United States.
THREATS TO BLACK BEARS
Today, a major threat to the American black bear is poaching, or illegal killing, to supply Asian markets with bear galls and paws, considered to have medicinal value in China, Japan, and Korea. The demand for these parts also affects grizzly and polar bears. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), a treaty among more than 120 nations, provides measures to curb illegal trade in wildlife and wildlife products across international boundaries, helping to protect the black bear from poaching.
Black bears are abundant in much of the West, in portions of the Midwest and in most of Canada. Conversely, Iowa, where land is heavily used for agriculture, has virtually none. Most eastern populations in the United States are seeing a marked, steady increase in population with bears moving back into places where they may not have been present for over a century as suitable habitat has come back. Two populations, however, are at critically low levels. Two subspecies, the Louisiana black bear and the Florida black bear, still face decline mainly due to habitat loss and degradation. In Mexico, the indigenous black bear population is listed as endangered and is mostly limited to increasingly fragmented habitat in the northern parts of the country.
In 1992, the U.S. Fish and Wildlife Service listed the Louisiana black bear subspecies as "threatened" under the Endangered Species Act, meaning it could be in danger of extinction throughout all or a significant portion of its range in the near future. The American black bear also is protected by legislation in the affected states (Louisiana, Mississippi, and Texas) due to its close resemblance to this subspecies. The Florida black bear is a candidate for protection under the Endangered Species Act.
Blue jays are large songbirds belonging to the crow family. Known for their blue plumage, perky crest and noisy calls, they are intelligent and complex and help spread oak trees. Blue jays inhabit North America in deciduous, coniferous and mixed forests, as well as parks and residential areas. They are frequent visitors of backyard bird feeders.
There are four subspecies of blue jay. The northern blue jay inhabits the northern U.S. and Canada and has dull plumage with pale blue coloration. The Florida blue jay is the smallest blue jay and is similar in color to the northern blue jay. The interior blue jay inhabits the Midwest U.S. The coastal blue jay inhabits the southern coasts of the eastern U.S. and is a vivid blue color.
While blue jays appear blue in color, their feathers actually have brown pigment. Special cells distort light creating the impression of a blue color. Blue jays have white faces, bellies and throats. Their wings and tails have white, blue and black plumage. Male blue jays are slightly larger than female blue jays.
Blue jays have a crest on the top of their heads. Blue jay crests stand erect when they are being aggressive, and stand brush-like when they are afraid. When they are relaxed, their crests are flattened. They easily recognize each other by the varying black bridles across their faces, napes and throats.
Blue jays are able to fly up to 25 miles per hour. They are diurnal, active during the day.
Blue jay are omnivores, feeding on seeds, nuts, fruit, insects, young birds and eggs. They have very strong bills capable of cracking nuts. Blue jays will often chase smaller birds away from food sources, but will wait their turn when larger birds are feeding. They store acorns in the ground and sometimes forget to retrieve them, helping in the spread of forests. Blue jays carry their food in their throats, beaks and the upper esophagus.
Blue jays are incredibly intelligent birds. They communicate with body language and high-pitched calls and loud screams. They have a very large vocabulary. Their characteristic jay call warns other birds of nearby predators. They are able to imitate the sounds of other animals, including humans. Blue jays imitate hawks to determine if any hawks are in the area and to distract other birds from a potential food source. Blue jays are very curious birds, and young blue jays often play with human-made objects.
Blue jays usually live in small family groups. When alone, blue jays are subject to predation, but when in groups they work together to fight off predators.
Some blue jays migrate. They may migrate every year, every other year, or only when winter food sources are scarce or weather conditions are extreme. Younger blue jays migrate more often than adult blue jays. When blue jays migrate, they gather in large flocks to begin their journey together.
Blue jays are preyed upon by owls, hawks and cats. Snakes, opossums, raccoons, crows and squirrels prey on baby blue jays and blue jay eggs.
Blue jay mating season takes place mid-March through July. Blue jay couples usually mate for life. Male blue jays collect twigs, roots, moss and bark to construct nests. Female blue jays build the cup-shaped nests in trees and lay 2 to 7 brownish or bluish eggs. Blue jays are very protective of their nesting sites. Following an incubation period of 16 to 18 days, hatchlings emerge from the eggs. Newborn blue jays are blind, naked and helpless. The father blue jay provides food for the mother blue jay while she nurtures the chicks. Young blue jays leave the nest after 17 to 21 days. They stay with their parents for one to two months. Blue jays reach sexual maturity at about one year old.
Blue jays can live up to 26 years in the wild.
THREATS TO BLUE JAYS
Blue jays are threatened by collisions with man-made structures, predation, pollution, pesticides and diseases. While considered a common bird, even common bird populations are alarmingly declining due to irresponsible human activities. Loss of habitat, animal agriculture, pesticides and forestry are the largest threats to bird populations. Collisions with power lines, buildings and vehicles kills 900 million birds each year in the United States and Canada alone.
Butterflies are part of the class of insects in the order Lepidoptera. Adult butterflies have large, often brightly colored wings, and conspicuous, fluttering flight. The group comprises the true butterflies (superfamily Papilionoidea), the skippers (superfamily Hesperioidea) and the moth-butterflies (superfamily Hedyloidea). Butterflies are the second largest group of pollinators, following bees. There are about 17,500 species of butterflies spread throughout the world.
These beautiful animals undergo a fascinating metamorphosis which takes place in four stages: egg, caterpillar, pupa and adult.
Mother butterflies attach their eggs with a special glue to caterpillar food, or “host” plant. As the glue hardens it contracts, deforming the shape of the egg. Each species of butterfly has its own host plant range, and while some species of butterfly are restricted to just one species of plant, others use a range of plant species.
Butterfly eggs are protected by a hard shell lined with a thin coating of wax which prevents the egg from drying out. Each egg contains a number of tiny funnel-shaped openings at one end that allow sperm to enter and fertilize the egg. Butterfly and moth eggs vary greatly in size between species.
The egg stage lasts a few weeks in most butterflies. Eggs laid close to winter, especially in temperate regions, go through a resting stage and the hatching may take place only in spring. Other butterflies may lay their eggs in the spring and have them hatch in the summer. These butterflies are usually northern species.
When the caterpillar is born, it eats its egg, then begins eating the host plant. Host plants often have toxic substances in them and caterpillars are able to retain them. This makes them unpalatable to birds, insects and other predators. Such unpalatibility is advertised using bright red, orange, black or white warning colors.
Caterpillars spend practically all of their time in search of food. Some caterpillars form mutual associations with ants. They communicate with the ants using vibrations and chemical signals. The ants provide some degree of protection to these caterpillars, and they in turn gather honeydew secretions. Others caterpillars communicate with ants to form a parasitic relationship.
Some caterpillars have the ability to inflate parts of their head to appear snake-like. Many have false eye-spots to enhance this effect. Some caterpillars produce foul-smelling chemicals used in defense.
When the caterpillar's insides grow too big for its outside, its covering splits and is shed. A new exoskeleton lies underneath. The caterpillar continues to shed numerous times, then becomes a pupa. It then seeks a sheltered spot, suspends itself by silken threads and sheds one more time forming a hard casing around its body. Inside this chrysalis, the pupa is growing six legs, a proboscis, antennae and wings. Within days, months or years, depending on the species, the chrysalis breaks open and a butterfly emerges.
Butterflies can live in the adult stage from a week to a year, depending on the species. They have four wings, usually brightly colored with unique patterns made up of tiny scales. They remember things they learned as caterpillars. They can fly up to 30 mph and up to 50 miles in a day. They learn home ranges and memorize locations of nectar and pollen sources, host plants and communal roosting sites. They are able to plan the most efficient routes by using calculations that mathematicians call the "traveling salesman algorithm".
Butterflies feed primarily on nectar from flowers. They are important as pollinators for some species of plants and are capable of moving pollen over greater distances than bees. Adult butterflies consume only liquids, ingested through the proboscis. They sip water from damp patches for hydration. They feed on nectar to obtain sugars for energy, and sodium and other minerals vital for reproduction. Several species of butterflies need more sodium than that provided by nectar and are attracted by sodium in salt; they sometimes land on people, attracted by the salt in human sweat. Some butterflies also visit dung, rotting fruit or carcasses to obtain minerals and nutrients. In many species, this mud-puddling behavior is restricted to the males, and the nutrients collected may be provided as a gift during mating.
Butterflies use their antennae to sense the air for wind and scents. The antennae are richly covered with sensory organs. Butterflies "taste" with their feet through tiny receptors. Their sense of taste is 200 times stronger than humans.
Butterflies have excellent vision and most species are sensitive to the ultraviolet spectrum. Some butterflies have organs of hearing and some species are also known to make stridulatory and clicking sounds.
Many butterflies are migratory and capable of long distance flights, using the sun to orient themselves. They migrate during the day and use the sun to orient themselves. They also perceive polarized light and use it for orientation when the sun is hidden.
Many species of butterfly maintain territories and actively chase other species or individuals that may stray into them. Some species will bask or perch on chosen perches. Basking is an activity which is more common in the cooler hours of the morning. Many species will orient themselves to gather heat from the sun. Some species have evolved dark wing-bases to help in gathering more heat. The flight styles of butterflies are often characteristic and some species have courtship flight displays.
THREATS TO BUTTERFLIES
The greatest threats to butterflies are habitat change and loss due to residential, commercial and agricultural development. Many butterfly species are either under the threat of extinction, or have died out completely due to the rise of intensive farming and the loss of habitats.
Butterflies have suffered from the loss of grasslands rich in wild flowers and the decline of woodlands.
Owls include about 200 species of mostly solitary and nocturnal birds of prey. They have an upright stance, a large, broad head, binocular vision and binaural hearing, and feathers adapted for silent flight. Owls hunt mostly small mammals, insects, and other birds, although a few species specialize in hunting fish. They are found in all regions of the earth except Antarctica and some remote islands. Owls are divided into two families: the true owls, Strigidae; and the barn-owls, Tytonidae.
Owls have large forward-facing eyes and ear-holes, a hawk-like beak, a flat face, and a circle of feathers around each eye. The feathers make up a disc that can be adjusted to sharply focus sounds that come from varying distances onto the owls' ears. Caught prey can be felt by owls with the use of filoplumes - feathers on the beak and feet that act as "feelers".
Most birds of prey have eyes on the sides of their heads, but the owl's forward-facing eyes permits a greater sense of depth perception necessary for low-light hunting. Although owls have binocular vision, their large eyes are fixed in their sockets - as are those of other birds - so they must turn their entire head to change views. Owls can rotate their heads and necks as much as 270 degrees, having fourteen neck vertebrae as compared to seven in humans. As owls are farsighted, they are unable to see clearly close up, but their far vision (particularly in low light) is exceptionally good. Owl eyes can move independently of each other.
The smallest owl - weighing as little as 1 oz and measuring 5 inches, is the elf owl. The largest owl by length is the great grey owl which measures around 28 inches on average and can attain a length of 33 inches. However, the heaviest (and largest winged) owls are two similarly-sized eagle owls; the Eurasian eagle-owl and Blakiston's fish owl. These two species can have a wingspan of 6.6 feet and a weight of 10 lb.
Different species of owls make different sounds; this wide range of calls aids owls in finding mates or announcing their presence to potential competitors.
Many species of owls have facial and head markings, including face masks, ear tufts and brightly colored irises. These markings are generally more common in species inhabiting open habitats, and are thought to be used in signaling with other owls in low light conditions.
Owl eggs usually have a white color and an almost spherical shape, and range in number from a few to a dozen, depending on species and the particular season. For most, three or four is the more common number. Eggs are laid at intervals of 1 to 3 days and do not hatch at the same time.
Most owls are nocturnal, actively hunting their prey only in darkness. Several types of owl, however, are crepuscular - active during the twilight hours of dawn and dusk. A few owls are active during the day.
All owls are carnivorous birds of prey and live mainly on a diet of insects and small rodents such as mice, rats and hares. Some owls are also specifically adapted to hunt fish. Much of the owls' hunting strategy depends on stealth and surprise. The dull coloration of their feathers can render them almost invisible under certain conditions. Their flight is practically silent. An owl's sharp beak and powerful talons allow it to kill its prey before swallowing it whole. They regurgitate the indigestible parts of their prey (such as bones, scales, and fur) in the form of pellets.
Owls can have either internal or external ears, both of which are asymmetrical. With ears set at different places on its skull, an owl is able to determine the direction from which the sound is coming by the minute difference in time that it takes for the sound waves to penetrate the left and right ears. The owl turns its head until the sound reaches both ears at the same time, at which point it is directly facing the source of the sound.
While the auditory and visual capabilities of the owl allow it to locate and pursue its prey, the talons and beak of the owl do the final work. The owl kills its prey by using the talons to crush the skull and knead the body. The beak of the owl is short, curved and downward-facing, and typically hooked at the tip for gripping and tearing.
The coloration of the owl’s plumage plays a key role in its ability to sit still and blend into the environment, making it nearly invisible to prey. Owls tend to mimic the coloration, and sometimes even the texture patterns, of their surroundings. Usually, the only tell-tale sign of a perched owl will be its vocalizations or its vividly colored eyes.
THREATS TO OWLS
All owls are listed in Appendix II of the international CITES treaty (the Convention on Illegal Trade in Endangered Species of Wild Fauna and Flora). Although owls have long been hunted, owl poaching may be on the rise. Owls are threatened by poisons and herbicides accumulated in rodents, vehicle collisions, entrapment in fences and wires, habitat loss, nesting site loss, disturbance by birders, and harassment by humans due to superstitions.
Owls are also victims of the animal entertainment industry. Keeping owls in captivity in tiny enclosures causes them emotional and psychological stress as a result of confinement and boredom. Even under the best of circumstances, captivity is cruel for wild animals. Confined to tiny areas and gawked at by crowds, animals in exhibits and acts endure constant stress. Without exercise, they become listless, their immune systems are weakened, and they become prone to sickness; many resort to self-mutilation in reaction to stress or boredom. Mental illness is rampant among confined animals. Torn from their families and deprived of all dignity, every part of their lives is controlled by their captors.
The salamander is an amphibian animal that has four legs, a slender and long body and a long tail. A salamander's rear legs develop more gradually than its front legs. (Toads and frogs are the opposite: their rear legs develop more rapidly than their front legs.) The four legs on a salamander are short to the point that its belly drags on ground. In spite of their lizard-like nature, salamanders are closely related to the smaller amphibians called newts.
Salamanders are found everywhere throughout the world, mostly in more temperate areas. One-third of the known salamander species are found in North America. The highest concentration of these is found in the Appalachian Mountains region. All the species of salamander are aquatic and semi-aquatic because of their permeable skin and amphibious nature.
There are more than 700 species of recognized salamanders all over the world, from the smaller species to the Chinese giant salamander. All the species of salamander look very much alike in appearance, however as with lizards, diverse species of salamander can possesses less limbs than normal, possessing a more eel-like appearance.
Like lizards and newts, salamanders are able to regenerate or regrow lost limbs and other parts of the body. This gives salamanders leeway while being chased by predators, as the salamander has the ability drop parts of its body to escape.
Some salamander species utilize tail autotomy to escape their predators. The tail drops off and also wriggles around for some time after an attack. The salamander either stays still or runs away while the predator is diverted. The tail regrows within time, and salamanders routinely regrow other complex tissues, including the retina or lens of their eyes. In just a couple of weeks of losing a part of a limb, a salamander reforms the missing parts.
The majority of salamander species are brightly colored, especially the male salamanders amid the breeding period when their colors get to be brighter and more intense to attract the female salamanders. Species of salamanders that live underground are mostly white or pink in color because their skin is never exposed to the sun.
The skin of salamanders secretes bodily fluid, which helps keep salamanders moist when on dry land and keeps up their salt balance while in water. It also provides a lubricant during swimming. Salamanders additionally secrete a poisonous substance from the glands in their skin, and some also possess skin glands for secreting courtship pheromones.
Respiration varies among the distinctive species and can include lungs, skin, gills, and the membranes of the throat and mouth. Larval salamanders breathe essentially by mean of gills that are mostly feathery and external in appearance. Water is drawn in via the mouth and flows out via the gill slits. Some neotenic species like the mudpuppy maintain their gills for the duration of their lives, however, most species lose them during metamorphosis.
Salamanders are opportunistic predators. They are generally not restricted to specific foods, but feed on almost any organism. Large species such as the Japanese giant salamander eat crabs, fish, small mammals, amphibians, and aquatic insects. Smaller salamanders may eat earthworms, flies, beetles, beetle larvae, leafhoppers, springtails, moths, spiders, grasshoppers, and mites.
A terrestrial salamander catches its prey by flicking out its sticky tongue in an action that takes less than half a second. An aquatic salamander lacks muscles in the tongue, and captures its prey in an entirely different manner. It grabs the food item, grasps it with its teeth, and adopts a kind of inertial feeding. This involves tossing its head about, drawing water sharply in and out of its mouth, and snapping its jaws which tears and macerates the prey before being swallowed.
Salamanders are not vocal and in most species the sexes look alike, so they use olfactory and tactile cues to identify potential mates. Pheromones play an important part in the process. In about 90% of all species, fertilization is internal. The male typically deposits a spermatophore on the ground or in the water according to species, and the female picks this up with her vent. Often an elaborate courtship behavior is involved in its deposition and collection. In the most primitive salamanders such as the Asiatic salamanders and the giant salamanders, external fertilization occurs, instead. In these species, the male releases sperm onto the egg mass in a reproductive process similar to that of typical frogs.
In temperate regions, reproduction is usually seasonal and salamanders may migrate to breeding grounds. Males usually arrive first and in some instances set up territories. Typically, a larval stage follows in which the babies are fully aquatic. The tadpoles are carnivorous and the larval stage may last from days to years, depending on species. Sometimes this stage is completely bypassed, and the eggs of most lungless salamanders develop directly into miniature versions of the adult without an intervening larval stage.
THREATS TO SALAMANDERS
A general decline in amphibian species has been linked with the fungal disease chytridiomycosis. A higher proportion of salamander species than of frogs or caecilians are in one of the at-risk categories established by the IUCN. Salamanders showed a significant diminution in numbers in the last few decades of the 20th century, although no direct link between the fungus and the population decline has yet been found. Deforestation, resulting in fragmentation of suitable habitats, and changes in climate are possible contributory factors.
The Chinese giant salamander, at 6 feet the largest amphibian in the world, is critically endangered, as it is collected for food and for use in traditional Chinese medicine. The hellbender is another large, long-lived species with dwindling numbers and fewer juveniles reaching maturity than previously. Habitat loss, silting of streams, pollution and disease have all been implicated in the decline.
Of the 20 species of minute salamanders in Mexico, half are believed to have become extinct and most of the others are critically endangered. Specific reasons for the decline may include climate change, chytridiomycosis, or volcanic activity, but the main threat is habitat destruction as logging, agricultural activities, and human settlement reduce their often tiny, fragmented ranges.
There are nearly 100 species of lemurs. All are endangered. Hunting and habitat destruction threaten their future.
Lemurs share many common primate traits, such as divergent digits on their hands and feet, and nails instead of claws (in most species). Their brain-to-body size ratio is smaller than that of anthropoid primates, and they have a "wet nose". They range in size from 1.1 oz to 20 lb and can reach 30 years old or more.
Lemurs are found naturally only on the island of Madagascar and some smaller surrounding islands, including the Comoros (where it is likely they were introduced by humans). Fossil evidence indicates that they made their way across the ocean after Madagascar broke away from the continent of Africa. While their ancestors were displaced in the rest of the world by monkeys, apes, and other primates, the lemurs were safe from competition on Madagascar and differentiated into a number of species. The larger species have all become extinct since humans settled on Madagascar. Until shortly after humans arrived on the island around 2,000 years ago, there were lemurs as large as a male gorilla. Typically, the smaller lemurs are active at night (nocturnal), while the larger ones are active during the day (diurnal).
The small cheirogaleoids are generally omnivores, eating a variety of fruits, flowers and leaves (and sometimes nectar) as well as insects, spiders and small vertebrates. The remainder of the lemurs, the lemuroids, are primarily herbivores, although some species supplement their diet with insects. They inhabit highland country and thinly wooded forests.
Lemurs are social and live in groups that usually include less than 15 individuals. Nocturnal lemurs are mostly solitary but social, foraging alone at night but often nesting in groups during the day. In many nocturnal species, the females, along with their young, will share nests with other females and possibly one male, whose larger home range happens to overlap one or more female nesting groups. In sportive lemurs and fork-marked lemurs, one or two females may share a home range, possibly with a male. In addition to sharing nests, they will also interact vocally or physically with their range and mate. Diurnal lemurs live in relatively permanent and cohesive social groups. Multi-male groups are the most common. True lemurs utilize this social system, often living in groups of ten or less. Dwarf lemurs are solitary but social, foraging alone but often sleeping in groups. Some lemurs exhibit female philopatry, where females stay within their natal range and the males migrate upon reaching maturity, and in other species both sexes will migrate. The presence of female social dominance sets lemurs apart from most other primates and mammals; in most primate societies, males are dominant unless females band together to form coalitions that displace them.
Lemur communication can be transmitted through sound, sight and smell (olfaction), using complex behaviors such as scent-marking and vocalizations. Lemurs have demonstrated distinct facial expressions including a threat stare, pulled back lips for submission, and pulled back ears along with flared nostrils during scent-marking. They have also been observed using yawns as threats. Their tails communicate distance, warn off neighboring troops and help locate troop members. Olfaction can communicate information about age, sex, reproductive status, as well as demarcate the boundaries of a territory. Small, nocturnal lemurs mark their territories with urine, while the larger, diurnal species use scent glands located on various parts of their anatomy. The ring-tailed lemur engages in "stink fights" by rubbing its tail across scent glands on its wrists, and then flicking its tail at other male opponents. Some lemurs defecate in specific areas, otherwise known as latrine behavior. Although many animals exhibit this behavior, it is a rare trait among primates. Latrine behavior can represent territorial marking and aid in interspecies signaling. Some of the most common calls among lemurs are predator alarm calls.
Lemurs not only respond to alarm calls of their own species, but also alarm calls of other species and those of non-predatory birds. The ring-tailed lemur and a few other species have different calls and reactions to specific types of predators. Lemur calls can also be very loud and carry long distances. Both ruffed lemurs and the indri exhibit contagious calling, where one individual or group starts a loud call and others within the area join in. The song of the indri can last 45 seconds to more than 3 minutes and tends to coordinate to form a stable duet. Tactile communication (touch) is mostly used by lemurs in the form of grooming, although the ring-tailed lemur also clumps together to sleep (in an order determined by rank), reaches out and touches adjacent members, and cuffs other members. Reaching out and touching another individual in this species has been shown to be a submissive behavior, done by younger or submissive animals towards older and more dominant members of the troop. Unlike anthropoid primates, lemur grooming seems to be more intimate and mutual, often directly reciprocated.
THREATS TO LEMURS
The habitat of lemurs is disappearing because of fires, overgrazing of domestic livestock and logging. Lemurs are also threatened by hunting. All lemurs are endangered species, due mainly to habitat destruction (deforestation) and hunting. Although conservation efforts are under way, options are limited because of the lemurs' limited range and because Madagascar is desperately poor. In some remote areas of Madagascar, the cultural motivation behind posting lemur hunting traps is that of indigenous superstition that lemurs are omens and harbingers of bad fortune.
The lemur pet trade is threatening the survival of many lemur species. Despite being illegal, thousands of lemurs are stolen from the wild in Madagascar. Lemur breeders peddle the animals through the internet to unqualified individuals who fail to realize that baby lemurs grow into sexually mature and aggressive adults. These animals are denied their wild nature, strong family bonds and social interaction with their own kind. They are destined to live a sad and lonely life in a cage.
Lemurs are also put on display by many zoos. Like "pet" lemurs, they are confined to tiny spaces and denied a natural life for the sake of human entertainment. Captive lemurs often become obese resulting in coronary heart disease and diabetes. They become inactive and lethargic, further threatening their health. Like all zoo animals, they face constant stress and boredom, often resulting in mental illness.
Woodchucks, groundhogs and whistlepigs – what do they all have in common? Although most people are familiar with the sight and sound of these rodents, few realize that the three names all refer to the same species. Belonging to the family Scuiridae, woodchucks are part of the group of larger ground squirrels referred to as marmots. Their habitat is broadly distributed across northeastern and central Canada and the USA, as far north as Alaska and as far south as Georgia.
Unlike their lighter tree squirrel relatives, ground squirrels typically remain on the ground, preferring to situate their burrows in open field or on the edge of woodland areas. They can readily climb trees though, and are also capable swimmers when they need to be. Woodchucks are the largest member of this family in North America, generally ranging from around 16 to 26 inches in length and 4 to 9lb in weight. In cases where predators are few and there’s a good food supply, woodchucks can even grow as large as 30 lbs in weight. Their plentiful numbers usually make them an ideal food source for foxes, coyotes, birds of prey, bears and wild dogs, meaning that the average lifespan for most groundhogs in the wild doesn’t exceed 5 or 6 years of age.
Like other burrowing rodents, woodchucks have characteristics that make for efficient soil removal; compact, cylindrical bodies with short, strong front legs and curved, thick claws. On average, a single woodchuck can move approximately 5500 lb of soil when digging a burrow. Their coat is double layered to provide insulation during colder weather, with a short, dense undercoat, and a longer topcoat of darker banded guard hairs. Their brush-like tail stands erect to provide a warning to other groundhogs when an individual is on the alert, and though they retreat to their burrows when they’re threatened, they can fight fiercely with their front incisors and claws if they’re cornered. Woodchucks also tend to be very vocal, communicating with others through a range of squeals, barks, whistles and tooth grinding noises.
As a defense against predators, groundhogs prefer to live in burrows. Although they’re often solitary, they may also live with several other individuals (particularly in the case of a mother with kits), and usually one or two members of a colony stand ‘guard duty’ at a time while others sleep or forage. These ground burrows are used for sleeping, hiding, raising offspring and hibernating, and typically have anywhere from two to five entrances to provide an easily accessible means of escaping predators. Despite the woodchuck’s size, their burrows are no small feat of excavation. The average burrow extends as much as 45 feet long and up to 5 feet underground – much like a small rodent city. Most groundhogs will also designate separate chambers in their burrows for sleeping, nesting, and depositing waste.
Woodchucks, like most other rodents, are mostly plant-eaters, preferring grasses, alfalfa, berries, tender bark and shoots from low tree branches, and planted crops when they’re available. They’ll also eat nuts, insects, grubs and snails, though not as often as other rodent relatives. They’re highly opportunistic and voracious foragers in warm weather, eating around 1/3 of their own body weight each day and building a thick layer of fat for survival over colder months when they enter their burrows to hibernate.
The groundhog’s hibernation cycle, and particularly the timing of its emergence from hibernation, is what makes the woodchuck so well known in popular culture. Many of us are familiar with the rituals of Groundhog Day. Woodchucks actually enter into a true hibernation, a behavior unique to only a few animal species, where the body’s processes slow down to conserve energy. These rodents build and enter their winter burrows (built in wooded areas below the frost line) when they’re at their maximum weight, and typically will hibernate from October to March, though this period is sometimes as short as three months in warmer climates. During this period, their body temperature drops drastically (to as low as 40 degrees Fahrenheit), and their metabolism, breathing and heart rate slow dramatically as well to minimize energy loss. Woodchucks then emerge in the spring with some remaining reserve of body fat to sustain them until sufficient plant growth appears.
Groundhogs are generally mature enough to mate in their second year of life, with the breeding season happening shortly after they wake from hibernation and emerge from their burrows. Mated pairs stay together in the den for approximately a month until the kits are born, but the male leaves as soon as the female is ready to give birth. She raises the young entirely on her own after that point. Woodchuck kits are blind, hairless and depend completely on their dam’s care and protection when they’re born, but mature very quickly, weaning and leaving their den at around 5 weeks of age. Kits often stay with the female for up to two months as she introduces them to their surroundings and teaches them behaviors to copy in order to survive and find food.
THREATS TO WOODCHUCKS
In most areas, woodchucks are unfairly viewed as nuisances because of their tendency to eat crops and burrow, which can compromise building foundations, and they aren’t currently considered threatened or endangered in North America. In some areas, in fact, woodchucks are very populous, and are hunted regularly for food, or to harvest their fur. They also tend to frequently fall victim to moving vehicles, since many build their burrows near grassy areas adjacent to roads and highways.
Snakes are long and legless carnivorous reptiles of the suborder Serpentes. Unlike legless lizards, they do not have eyelids and external ears. Snakes are vertebrates covered in overlapping scales, many with skulls that have several more joints than lizards allowing them to swallow much larger prey than the size of their heads. Because of their narrow bodies, their paired organs are lined up one in front of the other instead of side by side.
Snakes live on every continent except Antarctica. Their are about 3,400 known species of snakes. Different species vary in size from the tiny thread snake, only 10 cm long, to the giant reticulated python growing to over 20 feet long. Most species are not venomous, and those that are venomous use their venom primarily to kill and subdue prey, not for self-defense. Nonvenomous snakes swallow prey live or kill by constricting the prey. Because snakes are cold blooded and are not able to regulate their body temperature, they need sunlight to keep warm.
Sea snakes are widespread throughout the Indian and Pacific Oceans. Some sea snakes can breathe through their skin, allowing for longer dives underwater.
A snake's skin is covered in scales. They use their belly scales to grip surfaces to slither. Their eyelids are transparent scales and are always closed. When they sleep, they can close their retinas or bury their faces in the folds of their bodies. Snakes shed their entire outer layer of skin in one piece when they molt. Older snakes may molt only once or twice a year, while younger snakes may shed up to four times a year. Moulting replaces the old and worn skin and rids snakes of parasites such as ticks and mites. Snakes stop eating before molting and often hide. They crawl out of their old skin by rubbing against rough surfaces, revealing their new skin that formed underneath.
All snakes are carnivorous, eating insects, snails, small mammals, other snakes, birds, eggs and fish. Most snakes eat a variety of animals, while some specialize in certain species. Many snakes put out bait to lure prey to them.
Snakes smell with their tongues. They use smell to find their prey, using their forked tongues, constantly in motion, to collect particles from the air, water and ground to determine the presence of other animals. Snake vision varies greatly, with each species' sense of vision adapted to it's environment. Some snakes have infrared-sensitive receptors on their snouts, allowing them to see the heat of warm-blooded mammals. Snakes are also very sensitive to vibrations and can sense other animals by vibrations in the air and on the ground.
Certain snakes, such as cobras and vipers, use venom to immobilize or kill prey. The poisonous saliva is delivered through their fangs. Some mammals, birds and other snakes have developed a resistance to venom and are able to prey on venomous snakes. Some scientists believe that all snakes are venomous to a certain degree, with most snakes having very weak venom and no fangs. Other snakes kill by constriction – tightly wrapping around their prey to suffocate it. Many snakes simply swallow their prey alive.
Snakes are not able to bite or rip their food to pieces, so they swallow their food whole. Their flexible lower jaws, and other joints in their skull, allow them to open their mouths wide.
After snakes eat, they become dormant while digesting their food, an intense activity for snakes. The snake's digestive enzymes dissolve and absorb everything but the prey's hair (or feathers) and claws, which are excreted. A snake that is disturbed during the digestion period can regurgitate its prey to be able to escape easier.
Snakes are usually isolated creatures, coming into contact with each other occasionally. Most of the time they will go their own way, except during mating season. Different snakes use different tactics in acquiring their mates. Some males engage in ritual combat with other males to win females. “Topping” involves a male twisting around another standing male and forcing him down. Neck biting often takes place during combat. Females usually have the last say in whom will mate with them.
Most female snakes lay eggs, and most abandon the eggs after laying them. Some species, however, build nests and protect and care for their eggs. Some snakes "shiver" to produce heat to incubate their eggs. Other snakes keep their eggs inside their bodies until they are almost ready to hatch, and some give birth to live babies. Boa constrictors and green anacondas nourish their babies through a placenta and a yolk sac.
Where winters are cold, many snakes will brumate – similar to hibernation, but brumating reptiles remain awake but inactive. Some snakes brumate by themselves under rocks, in burrows or inside fallen trees. Other snakes gather together in large groups.
THREATS TO SNAKES
Many snake species are in danger of extinction. Snakes are killed for their skins, or simply out of fear. Snake habitats are being disturbed and destroyed by humans, or invaded by other, more aggressive animals that humans have introduced.
Snakes are also victims of the “pet” trade, inhumanely kept in captivity for the amusement of humans. These wild animals are deprived of their natural lifestyle, confined to small enclosures, and endure stress and health ailments from their unnatural living conditions.
Koalas have soft, wool-like fur that is gray above and white below. Their fur is mostly white on the underside below the neck, and their ears have long white hairs on the tips. The koala resembles a bear, but is actually a marsupial, a special kind of mammal which carries its young in a pouch. They are rather small, round animals, weigh about 30 pounds and on average grow to be 2 feet tall.
Koalas can live as long as 17 years, although high mortality rates (due to car fatalities and dogs) for males lower their life expectancy to 2 to 10 years. The koala's historic range stretches across Australia. Today they can be found only in Queensland, New South Wales, Victoria, and South Australia. There are fewer than 100,000 koalas left in the wild.
Koalas prefer to live in eucalyptus forests, coastal islands, and low woodlands. They consume eucalyptus leaves and bark from 12 different eucalyptus tree species. They also consume mistletoe and box leaves.
Nocturnal mammals, koalas sleep for up to 20 hours a day. They are arboreal, which means that they live in trees. They do not live in big groups but rather prefer to be alone. Females are solitary and occupy distinct home ranges that they rarely leave. In the more fertile areas, these ranges overlap; in areas where suitable food trees are scarce they tend to be larger and more exclusive. Males are not territorial, but do not tolerate one another, particularly not during the breeding season. Dominant individuals attack subordinate ones, and most adult males carry scars on their face, ears and forearms as a result.
The koala does not make nests, but sleeps in a tree fork or on a branch. It climbs using its powerful claws for gripping, usually moving quite slowly but can climb rapidly when needed.
The koala will leap confidently from one tree to another if they are reasonably close together. Its climbing is aided by a pair of thumbs on each paw, and it is the only other animal aside from primates to possess fingerprints. Longer distances are traversed on the ground in a slow but effective waddle. If threatened, the koala breaks into a surprisingly athletic gallop, heading for the nearest tree and bounding up it to a safe height. There the koala waits for the intruder to go away. The koala is also rather adept at swimming.
Koalas breed once a year. Gestation lasts 35 days, after which one koala is born. A baby koala is referred to as a joey and is hairless, blind and earless. At birth the joey, only the size of a jelly bean, crawls into the downward facing pouch on the mother's belly (which is closed by a drawstring like muscle that the mother can tighten at will) and attaches itself to one of the two teats. Young remain hidden in the pouch for about six months, only feeding on milk. During this time they grow ears, eyes and fur. The joey then begins to explore outside of the pouch. At about 30 weeks it has begun to eat the semi liquid form of the mother’s excrement called "pap". The baby koala will remain with the mother for another six months or so, riding on her back, and feeding on both milk and gum leaves until weaning is complete at about 12 months of age. Young females disperse to nearby areas at that time; young males often stay in the mother's home range until they are two or three years old.
THREATS TO KOALAS
Once numbering in the millions, koalas suffered major declines in population during the 1920s when they were hunted for their fur. The koala was hunted almost to extinction. Today, habitat destruction, traffic deaths, and attacks by dogs kill an estimated 4,000 koalas yearly. In recent years, some colonies have been hard hit by disease, especially chlamydia. The koala requires large areas of healthy, connected forest and will travel long distances along tree corridors in search of new territory and mates. The ever increasing human population of the coastal parts of the continent continues to cut these corridors by agricultural and residential development, forestry and road building...marooning koala colonies in decreasing areas of bush. Although the species covers a massive area, only 'pieces' of Koala habitat remain. These pieces need to be managed, protected and restored in a coordinated way. Presently, many are being lost to weeds, cleared for agriculture, or carved up by developers.
In contrast to the situation on much of the mainland, where populations are declining, the koalas of many island and isolated populations have flourished. In the absence of predators and competition, combined with an inability to migrate to new areas, koala populations can become unsustainable. Although culling has been suggested as a means to reduce koala numbers, this has met with fierce opposition both domestically and internationally, and the species remains protected. The popularity of the koala has made the possibility of a cull politically improbable, with any negative perception likely to impact on tourism and a government's electability. In place of a cull, sterilization and translocation programs have had only limited success in reducing numbers thus far, and remain expensive. There is evidence that koalas relocated to the mainland have difficulty establishing themselves in the different circumstances. A mooted alternative to the complex sterilization method, wherein the animal must first be captured, are hormonal implants that can be injected via darts.
Koalas displayed to the public for human entertainment are disturbed constantly by human visitors, putting them in an alert state which interrupts their normal activity resulting in chronic stress. This is even more hazardous for koalas than for other species, since koalas have an extremely low energy diet of eucalyptus leaves and must minimize energy by sleeping 18 to 20 hours a day. Even in captivity, koalas need to sleep most of the day. Some “wildlife parks” and zoos even allow hands-on experiences with koalas, increasing their level of stress.
Magpies are small to medium sized birds found throughout the globe. There are about 20 species of magpie spread across Asia, Europe, Africa, North America and parts of Australia. Magpie inhabit grasslands, open woodlands, farmlands, hedgerows, gardens and parks.
Magpies are closely related to crows, but the magpie has very distinguishable black and white feathers. The size of the magpie varies depending on species. Magpies looks much larger than they really are; their tails make up half their length. The average weight of a magpie is only half that of a pigeon.
The upper part of a magpie body and wings are black-colored with an iridescent green, blue and purple sheen. Their bellies, parts of their wings, flanks and ramps are covered with white plumage. Magpies have long, pointed beaks. Their wings are short and rounded. Their tails are long and wedge-shaped. Female magpies and male magpies look alike.
Magpies are known for being incredibly intelligent birds, and their ability to mimic the sounds of other birds. They are self-aware and are able to recognize their own reflections in mirrors. Magpies communicate via loud rattling calls.
Magpies are dominant and curious birds. They are very social and gregarious. Magpies have a confident demeanor and are often seen strutting about. They recognize and scold humans who they perceive to be threats to their nests.
Despite possessing large wings, magpies do not usually take long flights. They prefer to stay close to cover. When in flight, their long tails make it easy to maneuver through the air and rapidly change direction. Magpies will hide in bushes and trees to catch prey and hide from predators. They are able to sense approaching danger very quickly.
Magpies are omnivorous birds, feeding on a variety of seeds, nuts, fruits, insects, eggs, mammals, reptiles and amphibians. Magpies take advantage of new food sources created by humans.
Magpies have a reputation for collecting shiny objects to decorate their nests, but research shows that objects that are shiny actually repel magpies.
Magpie couples typically remain in their territories, but non-breeding magpies wander widely in bands or gangs. Magpies live in loose flocks during the summer months, and in large communities of about 200 birds during the winter months.
Magpies mate for life. Magpie mating season takes place in spring when the weather begins to warm. They usually build huge nests in the trees. If there are no suitable trees, magpies will build nests on the ground. A magpie nest has a roof, and often two entrances. Some magpies build open nests. Nests can take 50 days to construct. Old nests are often repaired and reused, or a new nest is built on top on the old nest. Female magpies lay up to 8 small eggs. Magpie babies hatch after an incubation period of about 3 weeks. Female magpies incubate the eggs; male magpies provide food for the mother. Both magpie parents take care of their babies. Magpie chicks are able to fly in about 3 to 4 weeks. They remain with their parents for about 2 months, then fly off to join other juvenile magpies.
Natural predators to magpies include dogs, foxes, cats and other birds.
Magpies live about 6 years in the wild.
THREATS TO MAGPIES
In some parts of the world magpie populations are in decline due to habitat loss, animal agriculture, pollution, pesticides and changes in climate.
Magpies are often considered pests, but they are an important part of the ecosystem. Magpies help control insect populations, clean up dead animals and garbage, and their nests are used by many other animals. Although magpies prey on songbirds, they do not have a significant impact on songbird populations. The real reason for the decline in small bird populations is habitat destruction. The misconception that magpies are pests results in thousands being caught and killed every year.
Dolphins belong to the same zoological order as whales. They are part of the family of toothed whales that also includes killer and pilot whales. They are mammals and breathe through a blowhole on the top of their head. Most dolphins have acute eyesight, both in and out of the water, and their sense of hearing is superior to that of humans. Though they have a small ear opening on each side of their head, it is believed that hearing underwater is also, if not exclusively, done with the lower jaw which conducts the sound vibrations to the middle ear via a fat filled cavity in the lower jaw bone. Hearing is also used for echolocation, which is an ability all dolphins have. The dolphin's sense of touch is also well developed.
The tucuxi is the smallest of the dolphin species. It is about five feet in length and weighs about 100 pounds. The largest dolphin species is the orca. Male orcas are about 18 feet in length and weigh about 19,000 pounds. Most species have a long lifespan. Some individuals may have lived for more than 100 years.
All but five of the 34 dolphin species live in tropical and temperate oceans. Five species live in rivers: baiji (Chinese River dolphin), boto (Amazon River dolphin), franciscana (La Plata River dolphin), Ganges River dolphin and Indus River dolphin. The baiji has been declared functionally extinct.
Using echolocation to find prey, dolphins eat a variety of food including fish, squid and crustaceans. Dolphins often hunt together, surrounding a school of fish, trapping the fish, and taking turns swimming through the school and catching fish. Dolphins will also follow seabirds, other whales and fishing boats to feed opportunistically on the fish they scare up or discard.
Dolphins are well known for their agility and playful behavior, making them a favorite of wildlife watchers. Many species will leap out of the water, spy-hop (rise vertically out of the water to view their surroundings) and follow ships, often synchronizing their movements with one another. Scientists believe that by swimming alongside ships, a practice known as bow-riding, dolphins conserve energy. Dolphins live in social groups of five to several hundred.
Dolphins are widely believed to be among the most intelligent of all animals. Dolphins often leap above the water surface, sometimes performing acrobatic figures. Scientists aren't quite certain about the purpose of this behavior, but it may be to locate schools of fish by looking at above water signs, like feeding birds. They could also be communicating to other dolphins to join a hunt, attempting to dislodge parasites, or simply doing it for fun. Play is a very important part of dolphins' lives and they can often be observed playing with seaweed or playfighting with other dolphins. They have even been seen harassing other creatures, like seabirds and turtles. Dolphins also seem to enjoy riding waves and are frequently seen 'surfing' coastal swells and the bow waves of boats. They are also famous for their willingness to occasionally approach humans and playfully interact with them in the water. There are many stories of dolphins protecting shipwrecked sailors against sharks by swimming circles around the swimmers. A school of dolphins is also said to have pushed a fishing boat that was returning back out to sea after sensing the underwater disturbances generated by the 2004 Asian Tsunami.
Dolphins are social animals, living in pods (also called "schools") of up to a dozen animals. In places with a high abundance of food, schools can join temporarily, forming an aggregation called a superpod; such groupings may exceed 1,000 dolphins. The individuals communicate using a variety of clicks, whistles and other vocalizations. They also use ultrasonic sounds for echolocation. Membership in schools is not rigid; interchange is common. However, the animals can establish strong bonds between each other. This leads to them staying with injured or ill fellows for support.
Some dolphins teach their offspring to use tools. The animals break off sponges and put them onto their mouths, protecting the delicate body part during their hunt for fish on the seabed. This knowledge of how to use a tool is mostly transferred from mothers to daughters in dolphins, unlike simian primates, where the knowledge is generally passed onto all the offspring, irrespective of sex. The technology to use sponges as mouth protection is not genetically inherited, but a taught cultural behavior.
THREATS TO DOLPHINS
Threats to dolphins include marine pollution, habitat degradation, harvesting, low frequency sonar and entrapment in fishing gear. Some dolphin species face an uncertain future, especially the Amazon river dolphin and the Ganges river dolphin, which are critically or seriously endangered. Pesticides, heavy metals, plastics, and other industrial and agricultural pollutants that do not disintegrate rapidly in the environment concentrate in predators such as dolphins. Injuries or deaths due to collisions with boats, especially their propellers, are also common. Various fishing methods, most notably purse seine fishing for tuna and the use of drift and gill nets, kill many dolphins. In some parts of the world dolphins are killed in harpoon or drive hunts.
Hundreds of orcas, dolphins and other members of the dolphin family are held in captivity in the United States. While the Marine Mammal Protection Act (MMPA), passed in 1972, makes it more difficult to capture marine mammals from the wild, aquariums can still apply for permits or import animals caught in other countries. Whether wild caught or captive born, orcas and dolphins in captivity are sentenced to a life of confinement deprived of normal social and environmental interaction. Captured orcas and dolphins are confined to tanks as small as 24 feet by 24 feet wide and 6 feet deep. In tanks, the reverberations from their own sonar bouncing off walls drives some orcas and dolphins insane. Tanks are kept clean with chlorine, copper sulfate, and other harsh chemicals that irritate animals' eyes, causing many to swim with their eyes closed. Captured dolphins and orcas are often forced to learn tricks through food deprivation. Marine parks may withhold up to 60 percent of food before shows so that the animals will be "sharp" for performances. The stress of captivity is so great that some commit suicide.
The pygmy hippopotamus is a medium-sized herbivorous mammal inhabiting the humid forests and swamps of West Africa. The pygmy hippopotamus is very rare and is severely threatened by hunting and habitat loss.
Pygmy hippopotamuses inhabit Cote d'Ivoire and Liberia in western Africa, with small populations in neighboring Guinea and Sierra Leone. The pygmy hippopotamus prefers swampland and dense, lowland tropical forests. They spend most of their time foraging for food and resting on land.
The pygmy hippopotamus is closely related to the common hippopotamus, but is better adapted to dense forest environments. Pygmies are much smaller in size – weighing just a fifth of their cousin's weight. The pygmy hippopotamus has a sleeker body and narrower mouth and spends much less time in the water than the common hippopotamus. While the pygmy hippopotamus is semi-aquatic, they have fewer webbed toes to aid them in moving effectively on land. Their eyes are on the sides of their head, instead of on the top, to see better in the forest.
The pygmy hippopotamus has smaller canines, or tusks, than the common hippo. Their bodies are long and barrel-shaped, covered in slate-gray skin that lightens towards the underside. The head of the pygmy hippopotamus is small in relation to the body, and the mouth is narrow.
The pygmy hippopotamus does not live in herds like the common hippopotamus. They are mostly solitary or live in pairs. Pygmy home ranges often overlap and they are known to tolerate others in their territory. Males, called bulls, have larger territories than females, called cows. They both mark their homes with their droppings. Pygmy hippopotamuses spend most of the day resting in cool mud or in the burrow of animals. Being mostly nocturnal, the pygmy hippopotamus forages in the forest at night.
Pygmies are herbivores, feeding on a variety of plants and fruits. While the common hippopotamus eats mostly grasses, the pygmy hippopotamus has a much more varied diet including ferns, shrubs, leaves, grasses and fruits that have fallen to the forest floor. Pygmy hippos have multi-chambered stomachs that function like hoofed land animals, but they are more closely related to whales. Like the common hippopotamus, they do not chew their cud.
Pygmy hippopotamuses follow well-trodden trails and established tunnels when foraging, and can run at incredible speeds to escape danger. Spending most of their time on land, pygmy hippos enter the water when threatened. Pygmy hippos are excellent swimmers and have strong muscular valves that close off their ears and nostrils when they are in water.
Pygmy hippos are shy and quiet. They communicate primarily through body language. If alarmed, they release their breath with a loud huff. Signs of submission include lying and urinating while wagging their tails.
Pygmy hippopotamuses cannot sweat and their skin easily dries up. A pink, oily substance is secreted through their skin glands to prevent sunburn. It also has anti-bacterial properties that keeps wounds clean and prevents infections in dirty water.
Pygmy hippopotamuses can be more aggressive during the breeding season. Males will bare their teeth and sometimes fight to win females. Gestation lasts for six to seven months. The mother pygmy hippopotamus gives birth to a single baby in a den or in the water. Pygmy hippopotamus babies are weaned by eight months old. They then join their mothers on foraging trips.
Being large animals, the pygmy hippopotamus has few natural predators. They are sometimes stalked by leopards. Calves are preyed on by large snakes and wildcats when the mother is foraging. Unlike their larger cousins, pygmy hippos prefer to flee from danger rather than fight. They also use lunging, rearing, head shaking and water scooping tactics to scare off predators.
THREATS TO PYGMY HIPPOPOTAMUSES
The biggest threat to the pygmy hippopotamus is humans. Despite being protected by law, pygmy hippopotamuses are hunted for their meat and teeth. Their habitats are quickly being destroyed for animal agriculture. Their rivers are now polluted. Logging is illegal in many parts of their natural range, but continues to happen. There are fewer than 3,000 pygmy hippopotamuses left in the wild.
The pygmy hippopotamus is listed as Endangered in its natural environment and is severely at risk of extinction. The sub-species in Niger is Critically Endangered, and may already be extinct.
Pandas are famous for their black and white markings. The legs, shoulders, ears and oval patches around the eyes are black, and the rest of the coat is white. Good tree climbers, pandas can also swim to escape predators. Pandas use an enlarged wrist bone that looks like a thumb to grasp objects like bamboo. They weigh an average of 200 to 300 pounds and reach six feet in length.
The shrinking range of the panda is limited to parts of Szechuan, Shensi and Kansu provinces in central and western China. Only around 1,000 pandas exist in the wild, and about 60 in zoos. The panda’s lifespan in the wild is unknown but in captivity averages more than 20 years.
The panda lives in thick bamboo and coniferous forests (evergreens with seed cones) at 8,500 to 11,500 feet elevation. The panda’s digestive system does not absorb the fiber, so it must eat a lot. Despite being taxonomically a carnivore, the panda has a diet that is overwhelmingly herbivorous. The giant panda eats shoots and leaves, living almost entirely on bamboo. Pandas are also known to eat eggs, the occasional fish, and some insects along with their bamboo diet. These are necessary sources of protein.
These solitary animals spend most of their days feeding. Although they live in cold forests, pandas do not hibernate. They move to lower elevations during winter to keep warm and to higher elevations in summer to stay cool. They do not have permanent homes but sleep at the bottom of trees and under stumps and rock ledges.
After a gestation period of 125 to 150 days, a mother panda gives birth to one or two young, but only one survives. Eyes open at six to eight weeks, and the cub starts to move around at three months. Weaned at six months, the cub becomes independent after a year.
For many decades the precise taxonomic classification of the panda was under debate as both the giant panda and the distantly related red panda share characteristics of both bears and raccoons. However, genetic testing seems to have revealed that giant pandas are true bears and part of the Ursidae family. Its closest bear relative is the Spectacled Bear of South America.
The giant panda has long been a favorite of the public, at least partly on account of the fact that the species has an appealing baby like cuteness that makes it seem to resemble a living teddy bear. The fact that it is usually depicted reclining peacefully eating bamboo, as opposed to hunting, also adds to its image of innocence. Though the giant panda is often assumed docile because of their cuteness, they have been known to attack humans, usually assumed to be out of irritation rather than predatory behavior.
THREATS TO PANDAS
The future of pandas is threatened due to habitat loss from increasing human populations; poaching; and periodic bamboo die-offs. Giant pandas are an endangered species. Their main threat is habitat destruction. As the population of China continues to grow, panda habitat, and the bamboo they feed on, is lost to development. Mining and agriculture also threaten panda habitat, as well as tourists.
Since pandas reproduce so infrequently, it is difficult for their population to recover. Wildlife reserves in parts of China seek to maintain habit for pandas, though China has been criticized for showing little interest in true conservation. The Chinese government rents pandas to zoos around the world.
Few pandas have been born in zoos, and only a handful of those have been released into the wild; the majority of which did not survive. The enormous amount of money spent on panda breeding programs has been criticized, as the money could be used much more effectively by saving wild habitats.
Zoo pandas suffer the same stresses all wild animals face in captivity. They are moved from zoo to zoo, usually more for political and economic reasons rather than genetic management. Their natural habitat can never be truly simulated, leading to changes in behavior, prolonged inactivity, health problems, stereotypical behavior and lower levels of immunity creating higher susceptibility to illness and disease. Putting pandas' welfare above propaganda and profits, pandas should be put in refuges out of the public eye to eliminate the stress they endure due to such exposure.
Hippopotamus is an herbivorous, river-living mammal of tropical Africa. The large hippopotamus, hippopotamus amphibius, has a short-legged, broad body with a tough gray or brown hide. Males stand about 5 feet high at the shoulder and weigh about 5 tons; females are slightly smaller. Their mouths are wide, and the incisors and lower canines are large ivory tusks that grow throughout life. Their eyes are near the top of their heads, so they can see when nearly submerged.
The large hippopotamus outweighs all the many fresh water semi-aquatic mammals that inhabit our rivers, lakes and streams. The pygmy hippopotamus, though, are only 30 inches tall at the shoulder and weigh about 400 pounds. They tend to be solitary and spend much of their time on the shore, sleeping by day in thickets.
Recent DNA studies indicate that whales are most closely related to hippopotamuses. Hippopotamuses are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Artiodactyla, family Hippopotamidae.
Hippopotamuses usually live in herds of about 15 animals. Much of their time is spent standing or swimming underwater, where they feed on aquatic plants; they must rise to breathe every 5 minutes or so. At night, groups of animals feed on the shore.
The ancient Egyptians both feared and revered the hippopotamus. The word hippopotamus comes from the Greek for “river horse” and the hippo, once indigenous to Egypt, flourished there. They grazed along the fertile banks of the Nile River and swimming in its muddy waters. Hippos may seem slow and lumbering, but they can be ferocious, deadly killers. These prolific animals multiplied until the river was thick with them. They destroyed crops, up ended fishing boats and killed the men as they fell into the river. The ancient kings found sport in great hippopotamus hunts that would thin out the herds. Hunts became bloody battles between man and beast. The hippo is no longer found in Egypt. They were wiped out of that country in modern times because of the crop damage they caused, but the hippo still thrives in other parts of Africa.
After elephants and the white rhinoceros, the hippopotamus is the third largest land mammal on earth. On land, the enormous weight of a hippo is distributed evenly and is adequately supported by the four webbed toes on each of their feet. These animals are grayish in color with thick skin that is virtually hairless. The hippo has no sweat or sebaceous glands and must rely on the water to keep cool. A hippo’s skin has the unusual property of secreting a red fluid that protects them from the sun. This specialized excretion may also be a healing agent.
Female hippopotamus bear a single young and will give birth either on land or in shallow water. The mother helps the newborn to the surface of the water. In time, she will teach her baby to swim. Newborns can be seen in the river, resting on their mothers' backs. At birth, a baby hippo will weigh from 55 to 120 pounds. The mother must protect the baby from crocodiles in the water and lions on land. She must also ward off male hippos. Strangely, males do not bother baby hippos when on land, but they will attack them in the water.
Adult hippos can stay under water for up to six minutes. A young hippo can only stay submerged for about half a minute. In order to suckle under water, the baby must take a deep breath, close its nostrils and ears and then wrap its tongue tightly around the teat to suck. This instinctive behavior is the same when the baby suckles on land. Baby hippos start to eat grass at 3 weeks, but will continue to nurse until they are about one year old.
Hippos are usually found in groups of just over a dozen, presided over by a territorial bull. They have flexible social systems defined by food and water conditions and hierarchy. Periods of drought will force them to congregate in large numbers around a limited water supply. This overcrowding disrupts the system, and under these conditions there will be higher levels of aggression. Fights for dominance will be brutal with loud and frequent vocalization. Hippos can bear the scars of old, deep wounds sustained in such battles. A hippo establishes status and marks territory by spreading its excrement with its flat, paddle-like tail.
Hippos move surprisingly well, climbing adeptly up steep riverbanks to grazing areas. They spend the heat of the day in the water, leaving it to graze at night. Apparently creatures of habit, they enter and exit the water at the same spot. They will graze four to five hours, usually covering one or two miles. The amount of grass consumed is relatively modest for animals their size. A hippo’s appetite is in proportion to its sedentary life.
THREATS TO HIPPOS
The hippopotamus is hunted for meat, and Africans have used the hide for shields and whips. Once widespread in Africa, the animal is now rare except in unsettled areas and reserves.
Despite the fact that ditches and low fences can easily deter them from encroaching on cultivated areas, hippopotamus are slaughtered by the hundreds each year. These “controlled management” schemes are put forth less for crop protection than for the meat they yield. The fat and ivory tusks of the hippo are also of value to humans, as is the hippo’s grazing land. The hippos’ range was once from the Nile delta to the Cape, but the mighty river horse is now mostly confined to protected areas.
Tigers (Panthera tigris) are mammals of the Felidae family and one of four "big cats" in the panthera genus. They are predatory carnivores and the largest and most powerful of all living cat species. The Indian subcontinent is home to more than 80% of the wild tigers in the world. Tigers breed well in captivity, and the captive population in the United States may rival the wild population of the world.
Most tigers live in forests or grasslands, for which their camouflage is ideally suited, and where it is easy to hunt prey that is faster or more agile. Among the big cats, only the tiger and jaguar are strong swimmers; tigers are often found bathing in ponds, lakes, and rivers.
Although different subspecies of tiger have different characteristics, in general male tigers weigh between 400 and 715 pounds and females between 264 and 400 pounds. The males are between 5 feet 10 inches to 9 feet 1 inch in length, and the females are between 7 feet 6 inches and 9 feet in length. Of the living subspecies, Sumatran tigers are the smallest, and Amur or Siberian Tigers are the largest.
The stripes of most tigers vary from brown or hay to pure black. White tigers have far fewer apparent stripes. The form and density of stripes differs between subspecies, but most tigers have in excess of 100 stripes. The now extinct Javan tiger may have had far more than this. The pattern of stripes is unique to each animal, and thus could potentially be used to identify individuals, much in the same way as fingerprints are used to identify people. This is not, however, a preferred method of identification, due to the difficulty of recording the stripe pattern of a wild tiger.
It seems likely that the function of stripes is camouflage, serving to hide these animals from their prey. Few large animals have color vision as capable as that of humans, so the color is not as great of a problem as one might suppose. Tigers have red color vision. The stripe pattern is found on a tiger's skin, and if you shaved one, you would find that its distinctive camouflage pattern would be preserved.
Tigers have the longest and biggest canine teeth of all the wild cats. A tiger's canines are larger and longer than those of a similar-sized lion. The reason for this is likely due to the habit of preying on large herbivores in its habitat whose bones are thick and large; the tiger's canines have to be strong enough to break the bones of their prey. Moreover, as tigers hunt alone to bring down their prey, they have to work harder than lions, which hunt in groups.
Tigers often ambush their prey as other cats (including the domestic cat) do, overpowering their prey from any angle, using their body size and strength to knock prey off balance. Once prone, the tiger bites the back of the neck. For large prey, a bite to the throat is preferred. After biting, the tiger then uses its muscled forelimbs to hold onto the prey, bringing it to the ground. The tiger remains latched onto the neck until its prey dies. Powerful swimmers, tigers are known to kill prey while swimming. Some tigers have even ambushed boats for the fishermen on board or their catch of fish.
In the wild, tigers are one of the highest-jumping mammals, perhaps second only to the puma. Their forelimbs, massive and heavily muscled, are used to hold tightly onto the prey and to avoid being dislodged, especially by large prey such as gaurs. A single tremendous blow of the paw can kill a full-grown wolf.
Adult tigers are mostly solitary. They do not maintain strict territories, but their home ranges are often maintained unless threatened by other tigers. They follow specific trails within their ranges. Male home ranges may overlap those of many females, but males are intolerant of other males within their territory. Because of their aggressive nature, territorial disputes are violent and often end in the death of one of the males. To identify his territory, the male marks trees by spraying urine and anal gland secretions on trees as well as by marking trails with scat.
Males show a behavior called flehmen, a grimacing face, when identifying the condition of a female's reproductive condition by sniffing their urine markings. A female is only receptive for a few days and mating is frequent during that time period. A pair will copulate frequently and noisily, like other cats. The gestation period is 103 days and 3-4 cubs are born. The females rear them alone. Wandering male tigers may kill cubs to make the female receptive. At 8 weeks, the cubs are ready to follow their mother out of the den. The cubs become independent around 18 months of age, but it is not until they are around 2-2 1/2 years old that they leave their mother. The cubs reach sexual maturity by 3-4 years of age. The female tigers generally own territory near their mother, while males tend to wander in search of territory, which they acquire by fighting and eliminating a territorial male.
In the wild, tigers mostly feed on deer, wild boar, and wild cattle, including gaur and water buffaloes, young rhinos and elephants, and sometimes leopards and bears. Siberian tigers and brown bears are a serious threat to each other and both tend to avoid each other. Of all the land carnivores, the tiger is the only species that has been known to charge and take down a full-grown male elephant, one-on-one. However, due to the depletion of both species, these extraordinary confrontations become exceedingly rare and are hardly ever witnessed by humans in the wild.
THREATS TO TIGERS
Humans are the tiger's only serious predator, who often kill tigers illegally for their fur. Also, their bones and nearly all body parts are used in Chinese medicine for a range of purported uses including pain killers and aphrodisiacs. Poaching for fur and destruction of habitat have greatly reduced tiger populations in the wild, and it has been placed on the endangered species list.
The biggest threats to the tiger's survival are poaching, loss of habitat and the black market. In an effort to protect tigers from poachers and the rapidly increasing loss of land, wildlife reserves have been established. Most reserves, however, are isolated islands of habitat giving tigers little chance of survival due to disease, difficulty in acquiring mates and in-breeding. These “protected areas” are also difficult to defend from poachers. Habitat protection, combined with the promotion of alternatives to traditional Chinese remedies and stricter law enforcement, is vital to saving tigers.
Tigers have long been victims of the animal entertainment industry; forced to perform in circus acts or sentenced to a life in captivity for human entertainment. Animals used in the circus spend the majority of the year imprisoned in small cages or on chains, traveling from show to show. The training endured by circus animals is almost always based on intimidation; trainers must break the spirit of the animals in order to control them. Zoos are designed with the needs and desires of the visitors in mind, not the needs of the animals. Many animals in zoos exhibit abnormal behavior as a result of being deprived of their natural environments and social structures. Most animals in zoos were either captured from the wild or bred in captivity for the purpose of public display, not species protection. Captive bred zoo animals are rarely placed in the wild.
Of the three subspecies of gorilla, the mountain gorilla is the largest and rarest. Remarkably strong, the mountain gorilla has a short trunk and a broad chest and shoulders. Males develop a streak of silver hair on their backs when they mature and are called "silverbacks."
Male mountain gorillas reach an average of 6 feet tall (when standing upright) and weigh 400 to 500 pounds, making them the largest of the great apes (chimpanzees, orangutans, and gorillas). Females are smaller, standing an average of 4 to 5 feet tall and weighing 150 to 200 pounds.
The dense, forest ecosystems of the mountains of East Africa are the last remaining habitat of the mountain gorilla. Fewer than 650 mountain gorillas survive today in two geographically isolated populations. Approximately 320 gorillas inhabit the Virunga volcanoes region of Rwanda, Zaire, and Uganda, while the remaining number inhabits Uganda's Bwindi National Park. Gorillas live up to 53 years.
Mountain gorillas eat large amounts of vegetation and spend about 30 percent of each day foraging for food. They consume roots, leaves, stems of herbs, vines, bark from trees, shrub-sized plants, and bamboo shoots.
Mountain gorillas are shy, retiring animals. They live in social groups of 2 to 35 individuals. An adult male silverback is the leader and protector of his band, which consists of females and offspring. Silverbacks will charge anything that threatens them or their group and are known for their chest beating displays when in danger.
A silverback is an adult male gorilla, typically more than 12 years of age and named for the distinctive patch of silver hair on his back. A silverback gorilla has large canines that come with maturity. Blackbacks are sexually mature males of up to 11 years of age. Silverbacks are the strong, dominant troop leaders. Each typically leads a troop of 5 to 30 gorillas and is the center of the troop's attention, making all the decisions, mediating conflicts, determining the movements of the group, leading the others to feeding sites and taking responsibility for the safety and well being of the troop.
Males will slowly begin to leave their original troop when they are about 11 years old, traveling alone or with a group of other males for 2–5 years before being able to attract females to form a new group and start breeding. While infant gorillas normally stay with their mother for 3–4 years, silverbacks will care for weaned young orphans.
If challenged by a younger or even by an outsider male, a silverback will scream, beat his chest, break branches, bare his teeth, then charge forward. Sometimes a younger male in the group can take over leadership from an old male. If the leader is killed by disease, accident, fighting or poachers, the group will split up, as animals disperse to look for a new protective male. Very occasionally, a group might be taken over in its entirety by another male. There is a strong risk that the new male may kill the infants of the dead silverback.
Females reach breeding age at about 10 years old. They typically bear young every four to five years, giving birth after a gestation period of eight to nine months. Young gorillas cling to their mother's chests until they are old enough to ride on her back. A young gorilla remains with its mother until 5 years of age.
Gorillas are closely related to humans and are considered highly intelligent. A few individuals in captivity, such as Koko, have been taught a subset of sign language. Gorillas are known to use tools in the wild; as all of the great apes are now known to use tools.
THREATS TO GORILLAS
The eastern gorilla is listed as endangered on the IUCN Red List, with the mountain gorilla listed as Critically Endangered. The western gorilla and its subspecies are also listed as Critically Endangered. Threats to gorilla survival include habitat destruction and poaching for the bushmeat trade. The Ebola virus also threatens gorillas.
Gorillas are often victims of captivity for human entertainment. Even under the best of circumstances, captivity is cruel for gorillas. Confined to tiny cages and gawked at by crowds, animals in exhibits and acts endure constant stress. They may suffer from temperature extremes and irregular feeding and watering. Without exercise, they become listless, their immune systems are weakened, and they become prone to sickness; many resort to self-mutilation in reaction to stress or boredom. Mental illness is rampant among confined animals. Torn from their families and deprived of all dignity, every part of their lives is controlled by their captors.
Animals used in film, television, advertising or as sports mascots are ripped away from their mothers as infants. They are forced to spend most of their lives in small cages. They often live alone, resulting in severe psychological anxiety. “Performing” is stressful, confusing and often torturous. Training methods may involve beating the animals, causing them to be constantly anxious and fearful. When the animals become too large to handle, they are often dumped at shoddy roadside zoos and other substandard facilities, where they spend the rest of their lives in small, barren cages—many in solitary confinement. “Retirement” from entertainment is a long life of misery for these highly intelligent and sensitive animals. The American Humane Association’s (AHA) “No Animals Were Harmed” seal of approval is extremely misleading. AHA does not monitor living conditions of animals off set, during pre-production training, or during the premature separation of infants from their mothers.
While zoos and aquariums may appear to be educational and conservation-oriented, most are designed with the needs and desires of the visitors in mind, not the needs of the animals. Many animals in zoos and aquariums exhibit abnormal behavior as a result of being deprived of their natural environments and social structures. When the facility breeds too many animals they become "surplus" and often are sold to laboratories, traveling shows, shooting ranches, or to private individuals who may be unqualified to care for them.