Mysteries and surprises abound in the nocturnal world of Leopards of Yala.

For more than a century, Yala National Park in Sri Lanka has been one of Asia’s most celebrated wildlife preserves, a lush windswept tropical forest rich in rare aquatic birds and abundant with ferocious predators, such as crocodiles and sloth bears. But only in very recent years has Yala’s big cat distinction been brought to light: It contains one of the world’s largest concentrations of leopards. NATURE takes viewers deep into the jungle habitat of these elusive animals, in Leopards of Yala.

Over a period of six years, Jehan Kumara, a businessman from Sri Lanka’s capital city of Colombo, and Dr. Ravi Samarasinha, a physician from the local countryside, devoted their spare time to tracking leopards in Yala. In the course of their work, they are joined by Scottish cameraman Gordon Buchanan, attracted to Yala by the lure of finding the only big cat he had never captured on film.

To order a copy of Leopards of Yala, please visit the NATURE Shop.

Online content for Leopards of Yala was originally posted April 2003.

On any other day, the bulky package might have gone through. But on this day, a postal worker in Sri Lanka decided something was not quite right. Soon, his suspicions were confirmed: Inside the paper wrapping was the soft and beautiful fur of a Sri Lankan leopard — an endangered species that is protected by international law. The poachers had struck again.

Around the world, leopards are in trouble. The big spotted cats have been hunted to extinction in some areas, and their habitat — which ranges from dry desert to moist jungle — is under pressure from growing human populations. As NATURE’s Leopards of Yala shows, leopard lovers in Sri Lanka and elsewhere are taking steps to protect these powerful creatures. But while parks and preserves have helped save leopard habitat, the cat’s striking pelt continues to make it an attractive target for poachers. While not as fashionable as they once were, a leopard fur can still fetch thousands of dollars on the black market.

In Sri Lanka, researchers believe poaching has helped reduce leopard populations by up to 75 percent over the last century. While firm numbers are scarce, biologists estimate that less than 500 of the big cats remain in the island nation, which lies off India’s southern coast. Most are thought to be in three national parks, including the Yala preserve featured in Leopards of Yala.

Leopard furs can be worth thousands of dollars on the black market.

To get a better picture of Sri Lanka’s leopard populations, the Sri Lanka Wildlife Conservation Society is currently helping sponsor several studies. Among other findings, researchers have confirmed that the Sri Lankan leopard is a genetically-distinct suspecies (Panthera pardus kotiya) that has its own unique habits. But studying wild leopards isn’t easy, as they are expert at hiding themselves in the forest’s brush and shadows. And they are most active at night, further complicating surveys.

Researchers are also keeping an eye on poaching, which the society calls “one of biggest threats” to Sri Lanka’s leopards. Over the last few years, they have documented at least 25 leopards killed by poachers, but “it is obvious that many more leopards must be killed island-wide that go unrecorded,” society officials note. They’ve also surveyed historical records, turning up dozens of cases — including the 1996 discovery of the postal package holding the finely-prepared leopard skin. As in many other cases, police were never able to find the poacher.

In their hunt for profit, leopard poachers threaten more than just the cats, biologists note. They also threaten to destabilize entire ecosystems by removing a top predator. “The vital role that the Sri Lankan leopard plays [as] the only substantial predator in the ecosystem cannot be overstated,” say wildlife society biologists. “Removing this top cat from the arid zone environment, for example, would have dramatic consequences for a host of species lower on the food chain.” If the leopards don’t keep populations of grazing animals in check, for instance, the grazers could soon denude important forests and grasslands.

Leopard lovers hope to prevent such ecological catastrophes by learning more about leopard habits and answering key questions, such as how much territory the big cats need to survive. And, eventually, they hope that people will see that a leopard’s skin is more valuable on a living animal than it is on a wall.

Can the secrets of our past be found in the jungle? And what can it tell us about our future?

Accompany researchers in NATURE’s Deep Jungle: The Beast Within as they explore tropical forests for clues about the origins of humans and what our own future might hold.

In a bid to understand the genesis of human aggression, primatologist David Watts travels to Uganda’s Kibale National Park to study chimpanzees. In the past, researchers had witnessed these primates hunting, killing, and eating colobus monkeys. Watts, however, made a chilling new discovery that these primates also hunted and murdered their own kind. The theory under investigation is that violence may help chimp groups cement social ties.

In Brazil, clever capuchin monkeys use heavy rocks to crack open nuts for food. “Deep Jungle: The Beast Within” marks the first time the behavior has been captured on film. Tool use, which was previously thought to be a skill only of primates — humans and chimps — reminds us that human abilities arose long before the evolution of our species.

In Central America and Cambodia, archaeologists ponder the ruined remains of ancient cities that once flourished in the jungle. What might have happened to these lost civilizations? And can modern cities avoid the fate that befell those that came before?

In the Central African Republic, primatologist Chloe Cipolletta enlists the help of the BaAka people in her effort to preserve the jungle’s future. The BaAka have lived in the forest for generations, and are experts at tracking the elusive western lowland gorilla. Together, Chloe and the BaAka are gaining the gorilla’s trust and in return, the BaAka are learning to see the gorillas as more than a threat.

To order a copy of Deep Jungle, please visit the NATURE Shop.

Online content for Deep Jungle was originally posted in May 2005.

The Brazil Nut Industry — Past, Present, and Future
http://www.nybg.org/bsci/braznut/BrazilNut.html
Learn everything about the Brazil nut tree, from its phenology to its natural history.

Stranglers and Banyans: Amazing Figs of the Tropical Rain Forest
http://waynesword.palomar.edu/ploct99.htm
Get a sense of the amazing and bizarre behaviors of the wild fig trees that grow in the jungle.

BBC Radio: Adventures of the Spider Man
http://www.bbc.co.uk/radio4/science/spiderman.shtml
Listen to Martin Nicholas as he discusses his passion for spiders, preparations for his trip to Peru to find the chicken-eating spider, and finally, his successful sighting of the infamous tarantula.

Ask the Scientists: Bee Lines
http://www.pbs.org/safarchive/3_ask/archive/bio/
81_jniehanddroubik_bio.html
Bee experts David Roubik and James Nieh discuss their research on bees and bee communication.

Amazonia
http://nationalzoo.si.edu/Animals/Amazonia/glimpes.cfm
Learn more about the Amazon’s unique animals and plants. Take a virtual tour of the National Zoo’s Amazon exhibit, where visitors can view more than 350 species of plants and dozens of species of mammals, birds, insects, and more.

Passport to the Rainforest
http://passporttoknowledge.com/rainforest/intro.html
Explore the world’s largest rainforest through articles, video clips, and hands-on activities.

Monitoring the Brazilian Amazonian Forest
http://www.grid.inpe.br/
Satellite images show the yearly increments of deforestation in the Brazilian Amazon from 2000 to 2001.

PBS: Journey Into Amazonia
http://www.pbs.org/journeyintoamazonia/
JOURNEY INTO AMAZONIA features the swollen rivers, flooded forests, and dense canopy of the vast rainforest recognized as one of Earth’s natural wonders.

RELATED NATURE EPISODES

Deep Jungle: New Frontiers
http://www.pbs.org/wnet/nature/deepjungle/ep1/
Part I of the Deep Jungle miniseries.

Deep Jungle: The Beast Within
http://www.pbs.org/wnet/nature/deepjungle/ep3/
Part III of the Deep Jungle miniseries.

BOOKS

Pearce, Fred. DEEP JUNGLE. Cornwall, England: Eden Project Books, 2005.

Goulding, Michael. THE SMITHSONIAN ATLAS OF THE AMAZON. Washington, DC: Smithsonian Books, 2003.

—. AMAZON: THE FLOODED FOREST. New York: Sterling, 1990.

Raffles, Hugh. IN AMAZONIA: A NATURAL HISTORY. Princeton: Princeton University Press, 2002.

Smith, Nigel, et al. THE AMAZON RIVER FOREST: A NATURAL HISTORY OF PLANTS, ANIMALS, AND PEOPLE. Cambridge, UK: Oxford University Press, 1998.

Weil, Andrew. THE LOST AMAZON: THE PHOTOGRAPHIC JOURNEY OF RICHARD EVANS SCHULTES. New York: Chronicle Books, 2004.

In the Amazon — the world’s largest rainforest — trees fight to the death for water and sunlight. Giant spiders as big as dinner plates take shelter in underground lairs. Buzzing bees and scurrying mammals help hold together an amazing web of life that centers on the Brazil nut tree. One of the world’s largest rivers carries floodwaters that turn forests into massive lakes.

NATURE’s Deep Jungle: Monsters of the Forest takes you into the depths of the Amazon, home to millions of marvelous species. Here you will be treated to a front-row seat while….

Bee expert David Roubik takes on a hive of bees in the Peruvian jungle in an effort to understand the bizarre relationship among the bees, a fragrant orchid flower, and the towering Brazil nut tree.

Tarantula expert Martin Nicholas searches for a spider so big and fierce it can reputedly attack a chicken.

A sneaky strangler fig tree takes on a 160-foot-tall Brazil nut tree — and wins.

It’s all part of the amazing web of life that is the Amazon.

To order a copy of Deep Jungle, please visit the NATURE Shop.

Online content for Deep Jungle was originally posted in April 2005.

The foundation for the massive sandstone massifs was laid when South America and Africa made up the continent Godwanaland. Water and air are thought to have transported sand from nearby eroding mountain ranges to the area that would become the Guyana Highlands, home to the tepuis. When South America broke apart from Africa, about 180 million years ago, fissures and fractures formed in the highlands’ sandstone plateaus known as the Roraima Group. Forces within the earth lifted up some sections of the plateaus higher than others. Erosion over millions of years did the rest. Made of sandstone and quartz, the tepuis have been in their present form for the past 3 to 4 million years.

The towering tabletop mountains are found mostly in southeastern Venezuela, though some examples exist in northern Brazil and western Guyana. The largest and most imposing examples are located in Venezuela’s Canaima National Park.

The soil on top of the tepuis is acidic and poor in nutrients — a fact that makes some of the Lost World’s best-known plants carnivorous. On the top of some tepuis, dwarf forests can be seen; on others, meadows. Peat covers many of the summits. Jagged piles of quartz and sandstone jut out of the mountains’ surrounding savannas and jungles.

This is a humid environment and the area is crisscrossed with rivers and waterfalls (often seasonal), among which the 3,212-feet-tall Angel Falls — the world’s highest waterfall, located on the Churún River — serves as the star attraction. River beds of solid jasper in reds or oranges also provide an exotic touch — one of the most popular stops for tourists is at Jaspé Falls.

Temperatures generally range from 46° to 68° Fahrenheit. On the top of Mount Roraima, temperatures have dipped as low as 33.8° F, but no frost has been recorded. Rainfall is plentiful (79 to 157 inches per year) and humidity consistently high.

Angel Falls is more than three times the height of what famous monument?

The Empire State Building

The Eiffel Tower

The Great Pyramid of Giza

The Sears Tower

Want to go to Angel Falls? Prepare for an adventure. If you opt to depart from Canaima National Park on a dugout canoe with a Pemón guide, travel time can take up to three days during the dry season (roughly December to April) with plenty of canoe-carrying thrown in. During the wet season, canoe travel can be quite dangerous; some guides will outright refuse to go. If water doesn’t work, Avensa, Venezuela’s national carrier, also runs daily flights over the falls as part of a tour package to Canaima National Park. Failing that, there’s a less popular cross-country trek to the falls from Kavak or Uruyen tourist camps. Travel time? Between 6 to 10 days of hiking.

Producer: Ronnie Godeanu
Writer: Karen de Seve
Art Director: Sabina Daley
Graphic Art: Karen Mattson
Technical Director: Brian Patrick Lee
Scientific Consultant: Gianna Scaralia

Thirteen Online is a production of Thirteen/WNET New York’s Kravis Multimedia Education Center in New York City. Anthony Chapman, Director of Interactive & Broadband.

©1998 Thirteen/WNET New York

All Rights Reserved

Television Credits

A Co-Production of Thirteen/WNET and Survival Anglia Ltd.

Funder Credits

Funding for the TV series NATURE is made possible in part by Park Foundation. Major corporate support is provided by Canon U.S.A., Inc., Ford Motor Company, and TIAA-CREF. Additional support is provided by the nation’s public television stations.

We recommend these Web sites for those interested in the subjects shown on the program. All links are valid as of October 6, 2000.

Golden Lion Tamarin Basic Facts
http://nationalzoo.si.edu/conservationandscience/endangeredspecies/gltprogram/learn/basicfacts.cfm
Information from the National Zoo.

Marmosets and Tamarins
www.snowcrest.net/goehring/a2/primates/marmoset.htm
General information on these miniature monkeys.

Project Tamarin
http://proyectotiti.com/
A program to shore up the endangered cotton-top tamarin of Colombia, with fact sheets, a photo gallery, and extensive links.

Golden Lion Tamarin Reintroduction
http://nationalzoo.si.edu/ConservationAndScience/EndangeredSpecies/GLTProgram/
An article about the National Zoo’s effort to save golden lion tamarins from extinction.

The Belize Zoo — Margay
www.belizezoo.org/zoo/zoo/mammals/mar/mar1.html
An entry from the Belize Zoo’s animal archive, with information, photos, and a short video clip.

Print Resources

For those interested in the subjects shown in GREMLINS: FACES IN THE FOREST, we recommend the following books.

——. GRIZIMEK’S ANIMAL LIFE ENCYCLOPEDIA. Zurich: Kindler Verlag A.G., 1984.

Ancona, George. THE GOLDEN LION TAMARIN COMES HOME. New York: Macmillan, 1994.

Goldizen, Anne Wilson. TAMARINS AND MARMOSETS: COMMUNAL CARE OF OFFSPRING IN PRIMATE SOCIETIES. Chicago: The University of Chicago Press, 1987.

Macdonald, David, ed. THE ENCYCLOPEDIA OF MAMMALS. New York: Facts on File Publications, 1993.

Woolly monkeys live high in the trees.

The marmosets and tamarins of the NATURE program GREMLINS: FACES IN THE FOREST share the jungle with many other creatures. Here’s a look at some of them.

Woolly monkeys live in the South American rainforest from northern Colombia to Peru. Like marmosets and tamarins, they live in large families with as many as 20 other individuals. But those families grow slowly: female woolly monkeys give birth about every two years, which means that they are more vulnerable to population depletion from hunting and habitat loss. They inhabit a higher stratum of the forest world than gremlins do, remaining in the treetops a hundred feet above the smaller monkeys.

A member of the raccoon family, the kinkajou resides in Central and South America. It has a long, thin tongue that it uses to retrieve nectar from flowering plants, although it also eats fruit.

The boa constrictor is a predator to avoid in the Amazon jungle. Its decorated body blends in well with leaves, both on trees and on the ground. Rather than inject a victim with poisonous venom, the boa constrictor strangles its prey and swallows it whole, then digests it over three to four days, as you can see happen to a marmoset in the NATURE program. Adept tree climbers, boas can seize birds from midair. To swallow animals larger than their heads, the snakes unhinge their jaws.

Margays are excellent climbers.

Margays, also known as tiger cats, are small felines whose spots act as camouflage in the dense forest. The margay is the most agile climber of all the cats: it is the only member of the cat family whose ankle joints can rotate enough to allow it to climb down trees headfirst. Margays hunt after dark, relying on excellent night vision and a keen sense of smell.

The three-toed tree sloth, another creature of the trees, can barely walk on land. Saddled with an extremely slow metabolism that digests only leaves, the sloth moves at a crawling pace to conserve energy. Using its three claws as hooks to pull itself through the trees in search of leaves to eat, the three-toed sloth reaches a maximum speed of 0.15 miles per hour as it climbs.