NATURE has been the benchmark of natural history programs on television, capturing the splendors of the natural world from the African plains to the Antarctic ice. The series has won more than 600 honors from the television industry, parent groups, the international wildlife film community and environmental organizations, including 10 Emmys, three Peabodys and the first award given to a television program by the Sierra Club. A few NATURE films are featured below, including links to the full films, as well as episode-related video, articles, interviews, and more.

Salmon: Running the Gauntlet

The Columbia River Basin A mature Sockeye salmon about to be netted and taken to Eagle Hatcheryonce teemed with young salmon heading toward the ocean and mature salmon returning to their home rivers and streams to spawn. Now, many salmon species of the Pacific Northwest are extinct, and thirteen, including the iconic sockeye salmon, are currently endangered. When European Americans arrived in the area 150 years ago, the subsequent growth and change in population severely affected the ecosystems. Overfishing, habitat destruction, and dam construction contributed to salmon’s decline, which led, in the late-nineteenth century, to a new government-sanctioned industry created to restore dwindling salmon populations: hatcheries. Today, the salmon hatcheries of the Pacific Northwest provide controlled environments where early developmental stages of the salmon lifecycle are replicated within the confines of concrete walls; eggs are artificially fertilized and incubated in tubes and plastic bags, and young salmon are raised in tanks before being released into the wild.

Regrettably, however, those very systems set up with the intention of saving salmon are contributing to the species’ devastating decline. The hatcheries’ controlled environment strips salmon of the genetic diversity and natural instinct critical for their survival in the wild. Once released into open rivers and streams, these populations of fish are vulnerable to a variety of challenges they are unprepared to meet. Though ambitious efforts have been made to monitor and assist hatchery salmon in the wild -- from barge and truck transportation around dams, to predator relocation programs -- the results of those efforts have been essentially unsuccessful. It remains to be seen if the various efforts of legislators, biologists, engineers, and conservationists, including author David James Duncan and filmmaker Jim Norton, can restore salmon numbers, and in the process, restore the vital role salmon play in the health of the land, and in the lives of the animals and people that depend on them.

Watch the full episode of Salmon: Running the Gauntlet

Crash: A Tale of Two Species

With itsRed Knot armored shell, ancient anatomy, and 350-million-year lineage, the horseshoe crab almost seems too inconspicuous to stir up controversy. Yet this humble creature is at the very center of a collision between three completely different species.

For many decades, humans have harvested the horseshoe crab for use as fishing bait. Since the 1970s, we have also used horseshoe crab blood for medical purposes. The horseshoe crab’s unique blood has powerful properties valued by the biomedical industry that has created a lucrative industry. But we may have gone too far. Horseshoe crab numbers have declined significantly since the early 1990s. And, naturally, so did their egg numbers.

This is especially important to a small shorebird that is a global traveler of the most impressive kind. The red knot makes one of the longest migrations of any animal -- a journey that takes it from one end of the earth to the other. To accomplish this feat, it relies on the eggs of the horseshoe crab. Without these eggs, the red knot is in danger. Now, conservationists and scientists like Larry Niles are collecting data, and looking for creative solutions to guarantee the survival of both species.

Watch the full episode of Crash: A Tale of Two Species.

Cuba: An Accidental Eden

Cuba may have been restrictedYellow Polymita snail politically and economically for the past 50 years, but its borders have remained open to wildlife for which Cuba’s undeveloped islands are an irresistible draw. While many islands in the Caribbean have poisoned or paved over their ecological riches on land and in the sea in pursuit of a growing tourist industry, Cuba’s wild landscapes have remained virtually untouched, creating a safe haven for rare and intriguing indigenous animals, as well as for hundreds of species of migrating birds and marine creatures. Coral reefs have benefited, too. Independent research has shown that Cuba’s corals are doing much better than others both in the Caribbean and around the world.

Scientific research in Cuba on creatures such as the notoriously aggressive “jumping” crocodile, and the famous painted snails, paired with long-term ecological efforts on behalf of sea turtles, has been conducted primarily by devoted local experts. As the possibility of an end to the U.S. trade embargo looms, Cuba’s wildlife hangs in the balance. Most experts predict that the end of the embargo could have devastating results. Tourism could double, and the economic development associated with tourism and other industries could change the face of what was once a nearly pristine ecosystem. Or Cuba could set an example for development and conservation around the world, defining a new era of sustainability well beyond Cuba’s borders.

Watch the full episode of Cuba: An Accidental Eden.

River of No Return

Deep in the heart of Idaho Sunset on Middle Fork of the Salmon Riverlies the Frank Church-River of No Return Wilderness, part of the largest roadless area left in the lower 48 states. At 2.5 million acres, it is larger than Yellowstone, yet most people have never even heard of it. Designated a federally-protected wilderness in 1980 by Congress, the region is full of deep canyons and mountain forests, rivers and abundant wildlife. Otters and elk, deer and coyotes, blue birds and bighorn sheep, and newly-restored wolf populations all thrive there. Today, nine packs of wolves roam freely through the park, each pack dependent on family -- raising their young and hunting together.

Working with the Nez Perce Tribe in Central Idaho, wolf biologist Isaac Babcock spent 13 years participating in the wolf reintroduction program organized in the area. Wanting to share the raw beauty of the land and the wolves with his new wife, Bjornen, Isaac proposes spending a year there as an unconventional honeymoon, documenting their days as they go along.

Watch the full episode of River of No Return after the April 18 premiere on PBS.

Frogs: The Thin Green Line

Frogs have been living on this planet for more than 250 million years, and over the centuries, have evolved into some of the most wondrous and diverse creatures on earth. Today, however, all their remarkable adaptations and survival tactics are failing them. Recent discoveries are startling: more than a third of all amphibians -- most of which are frogs and toads -- have already been lost, and more are disappearing every day. It is an environmental crisis unfolding around the globe, traveling from Australia to North and South America. Habitat loss, pollution and a human population that has doubled in the past 50 years have set the stage for their diminished numbers. But now, a fungus called chytrid has been identified as the major culprit, and so far the spread of the fungus can’t be stopped. Chytrid continues to move quickly, extinguishing entire frog populations in a matter of months. Scientists have taken drastic measures to counteract it, such as evacuating frogs from the wild and sheltering them in a sterile environment.

Frogs may seem small and insignificant, but their bodies may hold the key to important new discoveries in medical research.  Scientists are finding that chemical compounds found in frogs’ skins can be used to treat pain and block infections, and are even being explored as HIV treatments. Our chances for the discovery of future medical miracles may be slipping away with the disappearance of these tiny creatures in our midst.

Their impact on the world’s ecosystems is great. Frogs sit right in the middle of the food chain, and without them, other creatures are disappearing, too. We are only just beginning to understand what life may be like without them. The race is on to stem the tide -- before the next frog crosses the thin, green line.

Watch the full episode of Frogs: The Thin Green Line.

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