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MammalsMammalsTIGERS TIGER, NO LAUGHING JOKE How is a tiger's face like your thumb? ANSWER: The stripes on the tiger's face are like your thumbprint. No two people have exactly the same thumbprint. And no two tigers have exactly the same stripe pattern. It takes a lot of muscle to move a 400-pound body (180 kilograms). And a tiger's body is packed with muscle. So it can leap 10 yards (9 meters) over level ground, or jump 15 feet (4.5 meters) in the air. Yet it can move so gracefully that it doesn't make a sound. Tigers are big-game hunters. They hunt water buffalo, wild pigs, deer, and other large animals. Water buffalo weigh more than a ton (900 kilograms). It would take 13 men to move such an enormous weight. Tigers are also big eaters. In a single year, one tiger must eat about Many people think that a big, dangerous tiger could easily kill all the prey it wants. But that's not true. In fact, the life of this big game hunter isn't easy. Most of the animals it tries to attack get away. It sometimes goes weeks without eating. And then it may hunt animals that can be dangerous, even for a tiger. To get enough food, tigers have to hunt day and night. They often hunt at night, because that's when deer and antelope are most active. Tigers also hunt at night because they are safe from humans then. When it hunts, a tiger usually sneaks close to its prey by hiding behind trees, bushes and rocks. Tigers cannot run fast for long distances. So they must get close to their prey before attacking. On their huge, padded feet, they can creep silently to within 20 feet (6 meters) of another animal without being heard. Its rear legs press beneath it, like a pair of giant springs about to be released. Then, in a series of explosive leaps, it attacks from behind. Next, the tiger grabs its prey with its claws and pulls it to the
ground. It bites the animal on the throat or on the back of the neck The tiger is a solitary animal, hunting mainly at night. The tiger's vision and sense of smell are relatively poor; the tiger will rely strongly on its sense of hearing, moving silently through the brush waiting to ambush its prey. The tiger's main diet consists of deer, antelope, wild pigs, and cattle. The man-eaters are all too often the sick and injured, too weak to hunt and capture wild animals. The tiger would much rather flee rather than stick around and put up a fight. Tigers are excellent swimmers and will often rest in pools of water
just to escape the heat, or, will swim from island to island such as in the SIBERIAN TIGER The largest of all living tigers lives in the coldest climate; but has thick fur to keep it warm. Its pale color makes it difficult to spot in the bleak, snowy landscape of Siberia and also makes it easier to get close to its prey. There are no more than 200 Siberian tigers living in the wild. INDIAN TIGER The Indian tiger is the most common tiger in the world today. In all, there are about 2,500 left, and most of them live in India. Hunting tigers used to be a sport for the rich people of India. But
it wasn't really a sport, because the tigers had little chance of escape. SUMATRAN TIGER Their stripes hide them as they stalk prey in the jungle. How? Their stripes look like the shadows of tall blades of grass, or like shadows and light playing across trees. For a fierce hunter, you'd think that food would be plentiful. Not true as most attacks fail. There may be weeks without eating. Some Sumatran villagers believe that the tiger holds magical powers and that it's very bad luck to kill them. SUMATRAN TIGER Tigers are among the most admired and most feared animals in the world. But we also think of beauty. We picture a tiger running swiftly through a jungle, or plowing through snowdrifts. Its muscles ripple. Its brilliantly striped orange and black coat gleams like satin. Its steely eyes glare into the distance as it looks for prey. This animal is a hunter. In fact, tigers are probably better than any other
land animal at capturing large prey single-handedly. Even so, the life of a
tiger is not easy. Finding food can be difficult, especially for a tiger
that is old or weak. What tigers have done to people is nothing compared to what people have done to tigers. Over the last 200 years, we have almost eliminated them in the wild. Today, they are one of the most endangered animals on earth. If humans do not disturb it, a tiger may live 20 years or more. Females
usually live longer than males, because the males live more dangerously. It isn't easy for people to tell a male tiger from a female, unless
the female happens to be with her cubs, because only females take care of
the young. Otherwise, the most obvious difference between males and females
is size. Male tigers are much bigger. An adult male Bengal or Indian tiger
usually weighs about 420 pounds (190 kilograms), and from head to rear, it
is roughly seven feet long (2 meters). Females are about a foot shorter (30
centimeters), and they weigh about one hundred pounds less (45 kilograms). Tigers once roamed over most of Asia. Some trekked over the frozen north, others climbed the jagged mountains of Central Asia, and many crept through the steamy jungles of the south. The tigers that lived in these different places gradually developed into a number of different types, or races. Although tigers have been able to live in different climates and landscapes, they have not been able to live alongside people. In fact, people have killed so many tigers that two races may already by extinct. The Bengal tiger is the most common tiger in the world today. In all,
there are about 2,500 Bengal tigers, and most of them live in India. The The Siberian tiger is the largest of all living tigers. It also lives
in the coldest climate, but it has very thick fur to keep it warm. And its
pale color makes it hard to see in the bleak, snowy landscape of Siberia. Sumatran and Javan tigers live on land south of the Asian continent. The body of a tiger is like a deadly weapon. It has the quickness and strength to take down animals twice its size. It has long, razor-sharp claws for grabbing its prey. And it has enormous teeth, which can easily kill large animals. But a tiger is also very quiet. It can sneak up on its prey without being seen or heard. And its stripes help it do this, because they make it easier for the tiger to hide. You will also discover another reason why a tiger's stripes are interesting. You can learn to tell one tiger from another by its stripes. Like other cats, tigers usually keel their claws hidden beneath the fur. This way the claws do not wear down too quickly. And they won't make noise when the tiger steps on rocks or hard ground. When it wants to use its claws for grabbing or scratching, the tiger will extend them. Tigers have longer canine teeth than any other predator. One of these
teeth is at least 10 times longer than the biggest tooth in your mouth. CUB LIFE Tigers and other predators play an important role in nature. By killing deer and other prey, they keep the numbers of these animals under control. And because of this, the animals that survive are healthier. If there were no tigers in the wild, the number of prey animals would grow too fast. At first, they would eat so much that they would destroy many plants. And then many of these animals would go hungry. A big, hungry tiger can eat about 100 pounds of meat (45 kilograms) at one sitting. This is about one fifth of its total weight. That would be like a 10-year-old human eating 40 hamburgers in one meal. Of course, a tiger has to eat this much because it often goes several days without eating anything. On occasion, a tiger will attack a baby rhino. This can be dangerous though, because the mother rhino is probably close by. And even a tiger does not want to make a four-thousand-pound rhino (1,800 kilograms) angry! If a tiger is hungry enough, it may even attack a bear. But that may be a big mistake. Baby tigers look like cute kittens. At birth, they are about 12 inches
long (30 centimeters), and they weigh less than two pounds (one kilogram). A mother tiger usually gives birth to two, three, or four cubs at a time. This is necessary so that at least one of her cubs will survive. Many predators attack tiger cubs. To help keep them safe, the mother stays with her cubs for three or four years. During this time, the young tigers have a lot to learn from her if they are to hunt and survive on their own. Animals, unlike man, must either capture prey, or, evade predators. In order for these animals, such as the tiger, to get close enough to its prey for the attack, these animals must be able to hide, or blend in with the background. That way the prey animal does not know that they are there… The tiger uses what is known as disruptive camouflage, which means that instead of blending in with it's surroundings, the tiger uses it's stripes to break it's outline, or familiar shapes into smaller unfamiliar shapes. Like all young animals, cubs are full of energy. They spend their days wrestling, chasing each other, and darting after butterflies. All this exercise helps prepare them for their first real hunt. And they are ready for this when they are about six months old. It's hard to believe that in just six months, a playful little cub will be a ferocious hunter. By then, it will weigh almost 200 pounds (90 kilograms) and have four big canine teeth for attacking prey. A female tiger is one of the most loving and caring mothers in the animal kingdom. She cuddles her babies to keep them warm. She feeds them and protects them from enemies. For three years or more she looks after them, teaching them how to hunt and survive in the wild. This cub is only a few weeks old. In the wild, cubs are usually born in caves and other protected places. The mother keeps them there and brings them food for about three months. After that, the cubs are big enough to follow her as she hunts for prey. The life of a baby tiger can be dangerous. If a mother leaves her cubs, even for a short time, they may be attacked by predators. Some of the animals that like to eat tiger cubs are leopards (left), pythons (below left), and hyenas (below right). LEOPARDS CLOUDED LEOPARD: PRECIOUS CARGO One chapter in the Zoological Society's clouded leopard story began
early in 1983 with the arrival of a young pair of cats from the People's In the exhibit, the female was accidentally exposed to a male, which severely mauled her right foreleg and shoulder. The injury was so severe that, because of the initial trauma and resulting fast-spreading infection, amputation of the leg and affected scapula were required to save her life. The difficult surgery was masterfully conducted. Intensive care was required for more than two months. The veterinary staff and a hospital team kept the cat alive through repeated tube-feeding and frequent hands-on care, despite the cat's aggressive distrust of such treatment. Following many weeks of this regimen, the cat responded and made sufficient recovery to allow her return to the leopard exhibit. A primary hurdle had been cleared -- the female had survived the injury. Next to be resolved were her adjustments to life on three legs and finding a method which would allow her reintroduction to the Chinese male. First, the mammal staff placed the cat in a program designed to help her grow accustomed to life with three legs. After several months of satisfactory progress, the staff decided to place her with the male, who had been kept in a separate but adjoining room. The animals were allowed to make contact as they chose. To the relief of all, the reintroduction was successful. The cats proved to be compatible, and, shortly after reintroduction, breeding took place. On the morning of April 25, 1984, final proof of the success of a long and difficult management program arrived-- a litter of two cubs. One cub did not survive, but the other was taken to the Children's Zoo to be raised by the nursery staff. UNIQUE FELINE The clouded Leopard has intrigued its public, been sought after for its fur, and mystified those who would try to categorize it. During the early morning hours of April 25, 1984, a discovery was made which was the culmination of a saga, which held elements of zoo diplomacy and goodwill, tragedy and suspense, cooperation and success. The discovery climaxed a chain of events surrounding this paradoxical cat. This cat has behavioral and physical traits typical of the small cats, genus Felis, and the big cats, genus Panther. A paradox to taxonomists and zoologists, it has been assigned to its own genus, Necrfelis, and is considered a bridge between the two larger genera. A relationship to the extinct saber toothed cat has even been suggested, based on the physical characteristic of having, in proportion to body size, the longest canines of all living felines. Its canine structure is also similar to that of the saber-toothed cat. The clouded leopard has a body size ranging from 24 to 42 inches (616- The clouded leopard was once believed to be exclusively arboreal and nocturnal. Recent observations in captivity and in the wild indicate, however, that it may be considerably more terrestrial and diurnal than previously thought. It is believed to prey upon birds, young buffalo, cattle, deer, goats, monkeys, pigs, and porcupines. The species is difficult to manage in captivity because of a tendency to be highly aggressive toward other species and humans. The exceptionally long canine teeth can easily inflict mortal injury. True to its paradoxical reputation, however, some cats may become extremely affectionate toward humans, even permitting and seeking physical contact. NORTH CHINESE LEOPARD This leopard is so rare that humans almost never see it in the wild. It makes its home in a great tangle of fallen trees and shrubs. When it kills smaller animals it devours them right away. But when it comes to larger prey, like deer and wild goats, the leopard drags the animal home to save for several meals. Don't be scared. The teeth of this snarling leopard won't hurt you. On the contrary. It's the snow leopard that should be afraid. Its relatives in the wild are in constant danger from poachers who want to shoot them for their pelts and teeth. Even though shooting leopards is illegal, it's considered "good business." That's because some people still wear leopard fur coats, and others believe that leopard teeth earrings and necklaces have special powers. SNOW LEOPARD: COLD WEATHER CAT The shy, nocturnal and virtually unknown Snow Leopard is classified with the big cats, but shares some small cat characteristics, for example it doesn't roar and it feeds in a crouched position. The Snow leopard has to contend with extremes of climate and its coat varies from fine in summer to thick in winter. The surfaces of its paws are covered by a cushion of hair, which increases the surface area, thus distributing the animal's with more evenly over soft snow and protecting its soles from the cold. Snow leopards are solitary except during the breeding season, (January
to May), when male and female hunt together, or when a female has young. Snow leopards are extremely rare in many parts of their range due to the demand for their skins by the fur trade. Although in many countries it is now illegal to use these furs, the trade continues and the species remains under threat. SNOW LEOPARD They live in the snow-covered mountain peaks of Central Asia. How high do these Asian Mountains rise? They reach 20,000 feet in altitude. The snow leopard's long, thick fur keeps it warm even in the frosty
air, and its creamy white and gray color camouflages it in the snow. HYENS SPOTTED HYENA This hyena is also known as the "laughing" hyena. Sometimes a hyena lets out a cry that resembles a wild human cackle. Did you know that a hyena can gorge up to 33 pounds of meat extremely fast? It needs to eat fast because as many as 50 other hungry hyenas may be next to it, noisily feeding on the same piece of meat. Scientists have seen 38 hyenas devour a zebra in 15 minutes, leaving only a few scraps behind. The hyena is famous for eating animal parts that other meat-eaters won't touch. You might even see it stamping and biting on an ostrich egg, trying to eat it. After devouring everything in sight, the hyena spits out the horns, hooves, and bone pieces, ligaments and hair. If there are leftovers, it buries the meat in a muddy pool. The hyena's good memory leads it back to the hidden food when it's hungry again. The spotted hyena hunts at night. Hyenas were once thought to be just scavengers (animals that eat the meat left behind by predators). But now we know that they're very good at finding their own food, too. Hunting together in large packs, hyenas have a very effective way of catching their favorite food. One hyena scares a herd of wildebeest, looks for the weakest member of the herd, and then begins a chase. The other hyenas join in the attack, and a wildebeest feast is soon ready. If you've ever heard the expression "laughing hyena" and wondered where it came from, it was inspired by the strange, laughter-like sound hyenas make when they're being attacked or chased. EATING HABITS True hyenas have thickset muzzles with large ears and eyes, powerful jaws and big cheek teeth to deal with a carnivorous diet. They walk on four- toed feet with five asymmetrical pads and nonretractile claws. The tail is long and bushy (less so in the spotted hyena). Spotted hyenas will eat almost anything, but in the wild much of their food comes from mammals heavier than 44 lb. which they mostly kill for themselves. The frequency of hunting depends on the availability of carrion; spotted hyenas will loot the kills of other carnivores, including lions. Group feeding is often noisy, but rarely involves serious fighting. Instead, each hyena gorges extremely rapidly on up to 33 lb. of flesh. Pieces of a carcass may be carried away to be consumed at leisure or, occasionally, stored underwater. It seems that the success of spotted hyenas is ensured through
individual and cooperative hunting and sharing of food between adults. WHY THEY LAUGH Hyenas are often called "solitary," a label which obscures the fact
that their social systems are among the most complex known for mammals. Calls audible to the unaided human ear include whoops, fast whoops, yells and a kind of demented cackle that gives this species its alternative name of laughing hyena. Whoop calls, in particular, are well-suited to long- range communication as they carry over several kilometers; each call is repeated a number of times, which helps the listener to locate the caller, and each hyena has a distinctive voice. Infant hyenas will answer the pre- recorded whoops of their mothers, but not those of other clan hyenas. LIONS AFRICAN LION: FAMILY CATS Lions are among the most admired animals on earth. Their strength and
beauty, combined with their bold nature, have fascinated people for ages. But lions don't always lead the easy lives of kings. They often need to work hard to survive. Lions are meat eaters, or carnivores, so they must hunt other animals for food. And sometimes prey is hard to find. When food is scarce, a lion may go for days without eating. Lions are members of the big cat family, which includes tigers, leopards, and jaguars. The main difference between the big cats and all other cats is that generally big cats can roar but cannot purr. Other cats can purr but cannot roar. The lion is one of the biggest cats in the world. Only the Siberian tiger is larger. A male lion may be 9 to 10 feet long (3 meters) and can weigh 500 pounds (227 kilograms) or more. Female lions are smaller. The average female is 7 to 8 feet long (2 l/2 meters) and weighs 270 to 350 pounds (140 kilograms). Lions are different from most other cats in that they live in groups called prides. They hunt together, guard their territory together, and raise their young together. Lions that live in groups can catch more food than a single lion can. And they can protect themselves better. Also, lions that are born into groups have a large family to care for them. There are two different kinds, or subspecies, of lions: the African
and the Asiatic. Most of the lions in the world today are African lions. Lions sometimes climb high up into trees to rest on their branches and escape the biting insects below. The body of a lion is made for catching prey. Most of the time, lions
try to get very close to their prey before they attack it. Then they make a
big leap and grab the prey. To help them get close without being seen,
lions have golden-brown coats that blend in with the land around them. And
to help them leap, they have strong muscles in their legs. A lion can leap Lions do most of their hunting at night, so they have wonderful hearing and eyesight to help them find prey in the dark. Their hearing is so sharp, they can hear prey that is more than a mile away. Lions can turn their ears from side to side to catch sounds coming from almost any direction. When a lion is moving through tall grass, it may not always be able to see its prey -- but it can always hear it. The eyes of lions are the biggest of any meat-eating animal. Like the eyes of other cats, they are specially made for seeing at night. Lions often work together when they hunt. By doing this, they increase their chances of getting food. A lion that hunts alone may have a hard time catching prey. Most of the hunting is done by a team of females. They divide the job among them, with each female doing part of the work to catch the prey. Some of the females scare prey animals and make them run -- while other females lie in ambush to grab the fleeing animals. The extra strength of a male is sometimes needed to bring down larger animals, like wildebeest or buffalo. And larger animals are the best prey, because they provide more meat. No matter how good a lion is at hunting, it misses more prey than it catches. Sometimes lions will go for days without eating. If lions can't find enough of their regular prey, they will eat smaller animals like hares and tortoises -- and even porcupines. When they can, lions get their food by taking it away from other animals. This is often easier than hunting. In some parts of Africa, much of the food that lions eat is taken away from hyenas. When food is really scarce, lions will eat almost anything they can find -- including snakes, locusts, termites, peanuts, fruit, and rotten wood. Baby lions are called cubs. And like most baby animals they need lots of loving care. A lion cub is totally helpless at birth. It is blind and can barely crawl. And it weighs less than 5 pounds (2 kg). Cubs are born in-groups called litters. Usually, there are three cubs in a litter. But sometimes there are as many as five. For the first few weeks of their lives, the cubs stay hidden in a safe place away from the pride. Then their mother brings them out to join the "family." In a pride, all of the females help take care of the cubs. When one mother is away hunting, the other lions feed and watch over her young. But sometimes, all of the adults join the hunt. Then the cubs are hidden in the tall grass or among the rocks. A cub is born with dark spots all over its body. Some people think that the spots may make it harder for predators to see the cubs when they are hidden. A mother lion carries her babies in her mouth -- just like a motherhouse cat. To keep predators from finding the cubs, she moves them to a new hiding place every few days. AFRICAN LION: FUTURE Asiatic lions are endangered, and African lions have less living space than in times past. This is because people are taking away their homes, or habitats. The human population in Africa and Asia is rapidly growing, and people are turning more and more land into farms and ranches. This means that the lions have less food to eat and so it is harder for them to live. Fortunately, wildlife organizations throughout the world are working hard to save the lions' habitats. And governments in both Africa and India have set aside special land where lions can live in safety. AFRICAN LION: THE MANE CAT Most experts agree that a lion will attack a human only if provoked. The lion is the largest of the African cats, weighing up to 200
kilograms (440 pounds). Of the big cats, only the tiger is of greater size. LION: NO LONGER KING You may have believed that African lions are the kings of the jungle. Lions, of course, are big cats, but they're different from tigers,
leopards and other big cats because they are very social animals. They live
in a group called a "pride," which can have as many as 35 lions in it. Hunting is how the lions get their food. They eat animals such as zebras, gazelles, hartebeests, gnus and even buffalo. Lionesses do most of the hunting but when it comes to eating, the adult males get their share first. Lions often hunt together. A couple of lions may chase the prey and herd it toward other lions hiding in the grass. Then the hiding lions leap out and ambush the prey. When lions eat, they often eat a whole lot of meat all at once. It's possible for a wild lion to eat up to 40 pounds of meat at one sitting. But then it may fast for several days and not eat anything. While it's fasting, the lion may be very, very lazy and just sleep a lot ... until its time to eat again. If you've ever heard the roar of a lion, you know what a thundering sound it is. It's very possible for a lion's roar to be heard five miles away if the wind conditions are right. Lions often roar just after the sun goes down. Male lions have manes around their necks. A young male will start to grow a mane when he's about a year old. It's believed that the mane helps protect the neck areas of males when they fight with each other. Baby lions are called cubs. A lioness will usually have three or four cubs in an area protected by rocks or brush. Many animals are born with their eyes closed, but it's possible for a lion cub to be born with its eyes open. The cubs are very playful and love to wrestle and stalk each other. Lionesses often care for each other's cubs, which is a little bit like baby-sitting. Although African lions aren't an endangered species, there's a lion subspecies that lives in Asia that is very rare and endangered. So remember: While you may not be able to call a lion the king of the jungle, there's certainly no reason you can't call him the king of beasts. ASIAN LION In the past, you could find hundreds of thousands of these lions in the Middle East and Asia. Now, they number only 180, living on a small wildlife preserve in India. Like the African lion, they've suffered from the destruction of wild lands and from over hunting. Once, people thought that Asian lions had shorter manes than African lions, but that's not the case. Both can have either long or short manes. WOLVES COYOTE: PLACE IN THE FOOD CHAIN Every animal on earth lives by eating some other living organism --
plant or animal. The sequence of eaten and eater is called a food chain. The coyote is called an ultimate consumer because nothing hunts it for food. But this food chain is a closed circle, the final link -- coyote -- being fastened to the first -- the grass. When the coyote dies, its chemicals are broken down by bacteria and returned to the soil, where they nurture more plant growth. Like many wild dogs, the coyote is usually active at night, when it can hunt safely. You can often see a coyote in the early evening and morning, as it goes to and from its nighttime activities. Coyotes can run as fast as 40 miles per hour, and at slightly slower speeds, they can run for miles. If a coyote can stay close to its prey, it has a good chance of getting a meal. DHOLE In hunting style, the dhole is like the hyena. It hunts in a pack with other dholes, whining, barking and whistling as they go. Whistling usually means that the hunt is unsuccessful, and the pack should reassemble for another try. It is almost impossible for a single dhole to kill a deer, but five to twelve dholes can manage it together. After the kill, dholes compete for the morsels by eating very fast. A dhole can chew up almost nine pounds of meat in an hour. Strong, wise, brave -- all these words describe the gray wolf. But another word needs to be added to the list: endangered. Two hundred years ago, the gray wolf roamed throughout North America. Today, the gray wolf continues to feel the impact of an expanding human population. That, and the popular belief that wolves shouldn't live near humans, continues to threaten their presence on our planet. GRAY WOLF Did you know that the gray wolf is the largest member of the dog family? Apart from man, it once was the most widespread mammal outside the tropics. As humans move into its habitat, the wolf had to move out. Did you know that after humans, wolves may be the most adaptable creatures of all? They're able to live in a wider variety of climates and habitats than most other animals and can survive on many different kinds of food. BEST LEFT UNPROVOKED Wolves prey on many species in the north -- musk ox, caribou, moose,
deer, hares and even rodents. These carnivores are among the most maligned
of all animals, victims of false myths and legends and systematic programs
of extinction. They are accused of attacking humans and destroying entire
herds of domestic animals. But their depredations of livestock are less
severe than often claimed. And unprovoked attacks by healthy wolves in The world will be a far lonelier place if the last wolf dies. As biologist Ernest P. Walker wrote in his book, MAMMALS OF THE WORLD, "The howl of the wolf and coyote, which to some people is of more enduring significance than superhighways and skyscrapers, should always remain a part of our heritage." . PRIMATS APES: FUTURE The future of apes is up to us. All of the great apes are already on
the endangered species list, and all of the lesser apes are as well. Gorillas and orangutans appear to have no natural enemies, and chimpanzees have very few. Gibbons, because they move so fast and live so high up in the trees, are safe from any animal. Nothing could threaten any of the apes with extinction until man started hunting them, capturing them, and destroying the wild lands in which they live. Today, hunting of apes is against the law everywhere, and there are strict regulations controlling the capture of wild apes. But illegal hunting and trapping continues. And the greatest threat of all -- the destruction of wild lands -- grows greater every day. Tropical forests are being cut down faster today than ever before ... at the rate of one acre every second, according to a recent report. At this incredible pace, the homes of many wild creatures -- including apes -- are simply disappearing. Most endangered of the apes are the mountain gorillas. Today, there are less than 500 in Central Africa. And the other apes are not much better off. Nobody is really sure how
many pygmy chimpanzees or bonobos survive in the jungles south of the Congo Fortunately, there are people who are trying to save the magnificent apes. In Central Africa, governments are working to protect the last remaining homes of mountain gorillas. They have even organized guards that patrol the borders of gorilla preserves to keep the gorillas safe from hunters. The World Wildlife Fund and other groups are raising money to buy land and make sure that it will never be taken away from gorillas, chimpanzees, orangutans, and gibbons. And scientists everywhere are studying the apes to find new ways to help them. BONOBO OR PYGMY CHIMPANZEE Biologists who have studied the behavior of these animals say they are the smarter of two species of chimpanzees. Their hair is parted at the middle and wisps out to the sides of the head, giving them an obvious physical distinction from the common chimpanzee. Both species of chimps are intelligent. They belong to the select animals that make and use tools. You might see a chimp defend himself with a tree branch, or take a twig and turn it into a useful devise for gathering or eating foods. Chimps also communicate with many gestures and vocalizations. People may feel especially drawn to chimps because of some similar behaviors. Young chimps laugh when they're tickled. Bonobos quarrel over food, but hug and kiss to make up. BONOBO: WORKSHOP IN CONSERVATION The bonobo or pygmy chimpanzee, is one of only four living species of
great apes. The other three species, the gorilla, orangutan, and common
chimpanzee, have received far greater attention until now. Not even
recognized as a separate species until 1929, the bonobo still remains much
of a mystery in its native habitat, the central rain forests of Zaire. The bonobo is as rare in zoos (there are less than 80 in captivity
worldwide) as it is in the wild (estimates range from 5,000 to 20,000). In No effective conservation plan for the bonobo could be developed
without firsthand knowledge of the only country that is home to this
critically endangered ape. International conservation projects are as much
a people issue as an animal issue; therefore, the needs of the local In light of the increasing awareness of the need to preserve the
world's biodiversity, it is quite surprising how little attention Zaire has
received. The extent and variety of the biological resources in Zaire's
forest ecosystems is matched by few other tropical countries. After Brazil, THE GORILLA SUBSPECIES Three subspecies of gorillas are currently recognized. Almost all zoo
gorillas are western lowland gorilla (Gorilla gorilla) native to west A very few eastern lowland gorillas (Gorilla gorilla graueri) native to eastern Zaire, live in zoos. Mbongo and Ngagi, the two "mountain gorillas" who lived at the San Diego Zoo in the 1930s and 1940s, would now be classified as eastern lowland gorillas. These gorillas are considered the largest subspecies on average, and generally have blacker hair than western lowland gorillas. They number approximately 3,000 to 4,000 and are classified as endangered. No mountain gorillas (Gorilla gorilla beringei) exist in captivity, but these are the most-studied gorillas in the wild. They live in the mountainous border regions of Rwanda, Uganda, and Zaire. Only about 600 individuals exist, in two separate populations, and they are classified as endangered. Mountain gorillas are distinguished physically by their large size and extra-long, silky black hair. A number of skeletal differences exist between the three subspecies as well. It would be interesting to see if DNA sequence comparisons could help us understand the phylogenetic (evolution of a genetically related group as distinguished from the development of the individual organism) relationships of the gorilla subspecies. This could help anthropologists understand the mechanisms and rates of primate evolution. It could also be important if gorilla populations ever become so critically depleted that interbreeding of different subspecies were contemplated. At CRES, we are comparing DNA sequences from gorillas of all three subspecies. Only a few gorillas have been tested so far, but to date it appears that the relationships between the subspecies generally follows the geographic location of populations. Western lowland gorillas have a large range, and many DNA sequence
differences exist between different individuals of this subspecies. Western
lowland gorillas are separated by 600 miles from eastern lowland gorillas,
and substantial sequence differences exist between the two groups as well. LION-TAILED MACAQUES: BACKGROUND The macaques, a genus of some 13 to 20 species (there is disagreement among taxonomists on the actual number), are found in North Africa and throughout southern Asia from Afghanistan to Japan. The most familiar form is the rhesus monkey, which is often seen by tourists in the towns and cities of India. Fossils dating to six million years indicate that the macaques originated in northern Africa and once roamed over Europe as far north as London. These earlier macaques were not very different in appearance from the Barbary monkeys that survive today in Morocco, Algeria, and on Gibraltar. However, once the Macaques reached Asia, at least by three million years ago, they diversified into a variety of forms. Few are as distinctly different as the lion-tails, with their black coats, silver facial ruffs, and strongly arboreal habitats. Lion-tails are one of the two macaque species that are listed as in danger of extinction, but we may realistically expect the Tibetan, Formosan, and Sulawesian species to fall into that category before the year 2000. Their geographical range snakes along the slope's and highest crests
of the Western Ghat Mountains where, today, the forest is reduced to about
one percent of the total land cover. Like its captive counterpart, the wild
living lion-tail was ignored by primatologists until well into the 1970s. In the wild state, lion-tail groups average about 20 individuals, usually with more than a single adult male present. Males are larger than females by about a third and are typically ranked relative to one another in a social hierarchy. Males usually emigrate from their natal group to join another during the early stages of adulthood. Being macaques, lion- tails are intensely social and are highly aggressive toward unfamiliar individuals. Preliminary work on our captive population indicates that much of the behavior between group members is dependent upon one's relationship to a small number of female-headed lineages. It is possible to have up to four living generations within each matriline and four or five matrilines within a group. Dominance relationships among and within matrilines play a crucial role in the everyday life of females and their offspring, as they do for adult males. One's social position determines access to essential resources such as food, perches, and social partners. LION-TAILED MACAQUES: FUTURE PLANS This highly endangered primate has been exhibited at the San Diego Zoo since 1923. In 1979, the existing population of three males and three females was relocated to the Primate Research Pad for concentrated study of their reproductive biology. Within the next decade their reproductive cycles were characterized, as were their sexual and social behavior, parturition and infant rearing, and various other aspects of the captive experience. Nearly a dozen scientific papers from these studies have been published in peer-reviewed journals or as book chapters. BY 1989 the Zoo's captive population had grown to 38 individuals. This same year the program undertook a significant change in direction. Seven individuals, including five born at the Primate Research Pad, were released into a state-of-the-art exhibit in Sun Bear Forest. Although these individuals are no longer under study, it was knowledge gained over the previous decade that contributed to the design of an exhibit facility which, by anyone's criteria, is an outstanding success. A second troop of 11 individuals was simultaneously relocated to the newly constructed 3/4-acre breeding kraal at the Wild Animal Park. It is this population which will be a major research focus during the next five years. This troop has been exempted from Species Survival Plan management, a program of the American Association of Zoological Parks and Aquariums, providing freedom to pursue several interesting lines of inquiry. One of these has to do with the impact of traditional management regimes on certain life history parameters. The second investigation will pursue experiments designed to prepare the troop for reintroduction to suitable habitat in India in five to seven years. The lion-tailed macaque is by nature a highly social mammal. Group members are organized in a social hierarchy that appears to remain stable over many years. Individual troops are highly xenophobic. This trait, combined with natural aggressiveness, results in potentially fatal conflict when new individuals are introduced. In the wild state, males will leave their natal troop at sexual maturity and join a new one. Females remain in their natal troops throughout their lives. Transfer by males is accompanied by a substantial amount of
aggression, but is presumably a necessary event to preclude inbreeding. It is relevant to ask if the ongoing disturbance of the social order through frequent inter-institutional transfers might negatively impact on such parameters as infant mortality, female fecundity, and perhaps even the neonatal sex ratio. Our kraal group has been together for the past 24 years, the only social disturbances having been the replacement of breeding males. We have learned how to integrate new males into groups with a minimum of social upheaval. We therefore have a unique opportunity to compare findings from our relatively undisturbed population with those from more traditionally managed populations in other zoos over the next several years. Preparation of this same troop for reintroduction to the wild has two components. The first entails a number of experimental procedures designed to "teach" natural foraging, avoidance of predators (including humans), and appropriate social cohesiveness. In addition, the troop must be routinely evaluated for any pathogens that would pose a hazard to the existing wild population. The second component is evaluation of potential release sites in the wild. The area selected for a test-case reintroduction must not only be protected from human activity, but must contain adequate food and shelter to insure the long-term survival of the troop. CRES anticipates working closely with Indian colleagues on this aspect. NIGHTTIME IS THE NORM: LABOR AND BIRTH IN THE LION-TAILED MACAQUE Lion-tailed macaque neonates (newborns) are born with black fur, and their faces, hands, and feet are pink and hairless. Their characteristic silver manes do not begin to grow in until the babies are several weeks old, and their faces gradually acquire the black pigmentation of adults. When the lion-tailed macaque breeding and management program began at the CRES primate facility more than ten years ago, little was known about the gestation, labor, and delivery of infants in this species. There was extensive documentation of parturition in some other macaques, but no comparable data were available on the much rarer lion-tailed macaque. How long is the normal gestation length? At what time are births most likely to occur? How long does labor last? What factors indicate that there may be a delivery problem requiring veterinary intervention? Answers to these and other important questions were needed in order to ensure the best captive management procedures and to maximize the breeding success for this species. The primary reason these data had not been collected previously is that most new infants were usually discovered in the morning, after the keepers arrived at work. We began collecting data on each lion-tailed macaque birth by setting up 24-hour "birth watches" that began several days before the dam was due to deliver. Conception dates were determined partially through hormone data from daily urine samples, and also by keeping careful track of menstruation, sex-skin swellings, and mating episodes. Parturition-date predictions were based on the 168-day gestation length documented for the rhesus macaque. However, because this is an average length, we began our observations about ten days before the due date in order not to miss the early deliveries. The birth watch involved round-the-clock observations at 15-minute
intervals during successive, 4-hour shifts. Observations were recorded by
keepers, technicians, and trained volunteers. As soon as any signs of
straining or birth fluids were noted, continuous notes were kept and each
subsequent contraction or birth-related event was timed and recorded. The first birth was to an experienced mother (this was her third
delivery) and was documented on videotape. After nearly 8 full hours of
labor and 188 contractions, the dam gave birth to a healthy, female infant. Over an 8-year period, we were able to collect data on 18 births from Our study determined that the average number of contractions to delivery for lion-tails was 54. The female with the longest labor also had the largest number of contractions (454). In her next delivery, the infant arrived after only 14 contractions, the lowest number recorded during the entire birth study. Based on the average number of contractions seen in 17 successful deliveries, and one ending in stillbirth, contraction frequencies approaching 75 to 100 in number may serve as a warning that intervention will be necessary. The average length of gestation for 14 pregnancies in our colony was Expulsion of the placenta always took place within about 20 minutes
after parturition, and usually it was immediately consumed by the mother. The lion-tailed macaque breeding colonies are now located in the Sun ZOONOOZ, May, 1990 "Nighttime Is the Norm: Labor and Birth in the Lion- tailed Macaque," by Helena Fitch-Snyder, Animal Behavior Specialist/CRES and Donald Lindburg, Ph.D. Behaviorist/CRES. MORE ON IGUANAS The environment in which a lizard lives may determine how easily its
scent marks can be located by other lizards. Both desert iguanas Desert iguanas have scent marks that are nonvolatile, which means that they evaporate very slowly into the atmosphere. These marks are also extremely resistant to chemical breakdown at high temperatures. The low volatility and thermal stability of desert iguana scent marks ensures that they persist under harsh desert conditions, a necessary quality if they are to be used effectively for territory marking. Although these characteristics make scent marks more durable in desert environments, they pose a problem for desert iguanas attempting to detect them if the marks are not volatile; they may be difficult or impossible to locate using smell. Desert iguanas avoid this problem by combining a unique type of visual signal with their scent marks. One striking property of desert iguana scent marks is that they strongly absorb ultraviolet light. Although these wavelengths are invisible to human eyes, they appear dark to animals able to see ultraviolet light -- much as ultraviolet-absorbing honey guides on flowers look black when UV- sensitive camera film is used to view them. Recent studies have shown that desert iguanas are able to see long-wave ultraviolet light, and they may use this adaptation to detect scent marks from a distance. After scent marks are localized using visual cues, desert iguanas can approach and investigate them in more detail through tongue-flicking. Although it is not known to occur in mammals, visual sensitivity to ultraviolet light has been shown in certain insects, spiders, fish, frogs, and birds. The ability of desert iguanas to detect ultraviolet light may help them solve some of the problems associated with finding scent marks in a desert environment. In contrast to those of desert iguanas, the scent marks of green iguanas contain a variety of volatile chemical compounds, and they do not absorb ultraviolet light. Behavioral studies indicate that green iguanas, unlike desert iguanas, can detect these scent marks by smell alone. Because the chemical components of green iguana scent marks remain active and transmit well under the humid conditions of tropical forests, green iguanas do not appear to need a visual cue in order to locate scent marks. Research on both iguana species demonstrates how the environment in which animals live can influence the nature of the communication signals they employ. |
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