Eels can be found all over the globe, in fresh and salt water ecosystems alike. But today, risk of over-fishing and the presence of dams and other obstacles that prevent eels from reaching their oceanic spawning grounds pose new threats to an animal that once roamed the planet alongside the dinosaurs. Artist, writer, and naturalist James Prosek explores the mysterious world of the eel.

Get an intimate look at the wildlife of Lapland, a region in northern Finland, the fabled home of Santa Claus and actual home of reindeer, great gray owls, wolverines, eagles, wolves, musk oxen, brown bears and more.

In Europe’s highest mountain range, discover how Eurasian lynx, griffon vultures, ibex, marmots and more face extreme seasonal fluctuations, from volatile thunderstorms and landslides of summer to avalanches and frozen temperatures of winter. In Part One of the miniseries “The Alps”, enjoy the Alps in spring and summertime as newborn animals grow up to face the coming brutal winter.

In the second and final part of NATURE’s miniseries “The Alps,” experience the hostile and bitter cold ecosystems of the Alps, shaped by snow blizzards and avalanches.

From early spring to late summer, follow new animal mothers through the trials of raising a family in the Rocky Mountains. Cranes migrate north to give birth, a bison mother protects her lambs from threats and young mountain goats learn to climb.

Young animals face new challenges as winter envelopes the Rocky Mountains, and spring means the end of childhood. A grizzly mom prepares her cubs for hibernation, a mountain lion raises her kittens and a bison calf must learn to survive the snow.

Examines the variety of plants and animals living in the Sargasso Sea, a gigantic floating bed of seaweed near Bermuda.

This program features the Kogi tribe who live in the Sierra Nevada de Santa Marta in Columbia. They are pre-Columbian peoples, and consider themselves as the elder brothers of humankind. They insist that it is the modern world, the younger brothers, who are destroying the harmony of life on earth.

The activities of an elusive female leopard are traced over a two-day period on the hot plains of Africa.

Explores the selection process among different species for choosing a mate, whether it’s for life or just for the day.

Cats command our attention and our devotion. These fascinating creatures have been perplexing people for thousands of years.

For centuries, the Tuareg people have braved the brutal Sahara to trade in salt, a precious cargo once worth its weight in gold. In this episode of AFRICA, Adam Ilius,salt production a young boy of nine, crosses hundreds of miles of desolate and dangerous desert on his first trans-Saharan salt caravan. After months of traveling, will Adam make it to Bilma, Niger to sell the caravan's salt for necessary food and clothing? Or will the shifting sands of the desert spell disaster for this tenacious group?

Scientists have discovered that natural poisons and venoms contain chemicals that can be used to create drugs for treating everything from chronic pain to cancer.

Patricia Clarkson narrates this look at the relationship between the sycamore fig tree and the tiny fig wasp, which is so small it could fly through the eye of a needle. The trees, which flourish in Kenya, produce fruit that provides nourishment to more wildlife than any other tree in Africa, but without the pollination the wasp provides, that might not occur. The documentary also examines other creatures that make the trees their homes, including gray hornbills (one of Africa's largest birds).

They are among the most reliable witnesses to a crime — expert in their testimony and bulletproof in their account. Yet they never utter a single word. They are the animals, plants, and insects that are being recruited by a special breed of forensic scientists to solve the most seemingly impenetrable of crimes.

"Jaguar: Year of the Cat" follows the predator in its native rain forests of Belize. Included: a pair stalk turtles, peccaries and armadillos; scenes of the habits of their animal neighbors, including toucans and ocelots.

A chronicle of hippopotamus life along the banks of Zambia's Luangwa River includes footage of males fighting over territory; females protecting their young; the hippo's importance to river ecology; and societal rituals involving the head male of the pod. Mark Hamill narrates.

Underdogs tells the poignant story of two misfit dogs whose lives were turned around by people who saw their potential for greatness.

A study of cheetah behavior follows a mother and her cubs on the Serengeti plains.

A gorilla orphanage and a proposed forest reserve may save the lowland gorilla.

The two-hundred-foot walls of ice in Glacier Bay overwhelm the senses, but they also surround the most beautiful sights Alaska has to offer — the Northern Lights, the roaming grizzly bears, and the humpback whales. The glacier itself is also creating new life — it has retreated some 70 miles up the bay, wiping the ecological slate clean, allowing new plants and animals to start again from scratch.

Charting the declining fortunes of a pride of "Crater Lions" that lives in Tanzania's Ngorongoro Crater. Included: lion attacks on buffaloes; a young cub's encounter with jackals; efforts to repopulate the pride; wildebeests, elephants

How does such a seemingly passive life form accomplish the complex task of reproduction?

Filmed in the mountains of Montana, this poignant, engrossing chronicle focuses on an extraordinary stallion, whose life has been recorded since his birth in the wild in 1995 by Emmy-winning filmmaker Ginger Kathrens.

Everyone loves macaws. Playful, intelligent, beautiful, they are the stars of parrot parks and zoos, and the cherished pets of devoted owners around the world. All of which makes them prime targets for poachers, who can make enormous profits from illegal sales of the birds. Thousands are smuggled from the wild each year, and many die in the process. In the forests of South America, several species of macaw are severely endangered. But there is hope on the horizon. Dr. Charlie Munn, a wealthy American who is also a leading ornithologist and world expert on parrots, has begun a campaign to promote eco-tourism as a means of saving the birds. Employing former poachers as conservationists, and providing locals with the means to start and maintain a trade in tourism instead of smuggling, he’s betting that instead of buying birds, their fans will pay to see them in the wild.