Kayaking Havasu National Wildlife Refuge – February 25, 2012

Kayaking the backwaters of the Colorado River north of Lake Havasu on February 25, 2012
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America Before Columbus — Part 1/3 — (National Geographic Documentary)

America Before Columbus -- Part 1/3 --  (National Geographic Documentary)

History books traditionally depict the pre-Columbus Americas as a pristine wilderness where small native villages lived in harmony with nature. But scientific evidence tells a very different story: When Columbus stepped ashore in 1492, millions of people were already living there. America wasn’t exactly a New World, but a very old one whose inhabitants had built a vast infrastructure of cities, orchards, canals and causeways.
The English brought honeybees to the Americas for honey, but the bees pollinated orchards along the East Coast. Thanks to the feral honeybees, many of the plants the Europeans brought, like apples and peaches, proliferated. Some 12,000 years ago, North American mammoths, ancient horses, and other large mammals vanished. The first horses in America since the Pleistocene era arrived with Columbus in 1493.
Settlers in the Americas told of rivers that had more fish than water. The South American potato helped spark a population explosion in Europe. In 1491, the Americas had few domesticated animals, and used the llama as their beast of burden.
In 1491, more people lived in the Americas than in Europe. The first conquistadors were sailors and adventurers. In 1492, the Americas were not a pristine wilderness but a crowded and managed landscape. The now barren Chaco Canyon was once covered with vegetation. Along with crops like wheat, weeds like dandelion were brought to America by Europeans.
It’s believed that the domestication of the turkey began in pre-Columbian Mexico, and did not exist in Europe in 1491. By 1500, European settlers and their plants and animals had altered much of the Americas’ landscape. While beans, potatoes, and maize from the Americas became major crops in continental Europe.
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Killer Whale vs Great White Shark (National Geographic Documentary)

Killer Whale vs Great White Shark (National Geographic Documentary)

The great white shark and the killer whale are the most formidable predators in the sea. These animals are so dangerous that they would never challenge each other…or so we thought. One morning, off the Californian coast, a boatload of tourists witnessed the ultimate clash of the titans: an unexpected killing challenges the great white shark’s supremacy as the ultimate predator when one became prey to a killer whale.

The Whale That Ate Jaws examines this extraordinary incident. Featuring amazing underwater footage of two whales feeding on the shark, this show reveals an astonishing new perspective on the relationship between the ocean’s two top predators.

We share information only for educational purposes

Amazing footage of a Killer Whale (Orca) attacking and partially eating a Great White shark, filmed by a whale watching tourist. During a whale watching trip for tourists near the marine sanctuary of the Farallon Islands, a Killer Whale was spotted and filmed as it broke the surface with a Great White shark gripped in its jaws. This was not only the first filming of such an incident, but also the first time marine biologists had even heard of such an attack. This incident lead to further research on the subject, finally convincing marine biologists that the Killer Whale was the top predator in all the oceans.

Killer whales are very sophisticated and effective predators. Thirty-two cetacean species have been recorded as killer whale prey, from examining either stomach contents, scarring on the prey’s body, or feeding activity. Groups even attack larger cetaceans such as minke whales, gray whales, and rarely sperm whales or blue whales.

Hunting large whales usually takes several hours. Killer whales generally choose to attack young or weak animals, instead. However, a group of five or more may attack a healthy adult. When hunting a young whale, a group chases it and its mother until they wear out. Eventually, they separate the pair and surround the calf, preventing it from surfacing to breathe, drowning it. Pods of female sperm whales sometimes protect themselves by forming a protective circle around their calves with their flukes facing outwards, using them to repel the attackers. Rarely, large killer whale pods can overwhelm even adult female sperm whales. Adult bull sperm whales, which are large, powerful and aggressive when threatened, and fully grown adult blue whales, which are possibly too large to overwhelm, are not believed to be prey for killer whales.

Other marine mammal prey species include nearly 20 species of seal, sea lion and fur seal. Walruses and sea otters are less frequently taken. Often, to avoid injury, killer whales disable their prey before killing and eating it. This may involve throwing it in the air, slapping it with their tails, ramming it, or breaching and landing on it. Sea lions are killed by head-butting or after a stunning blow from a tail fluke. In the Aleutian Islands, a decline in sea otter populations in the 1990s was controversially attributed by some scientists to killer whale predation, although with no direct evidence. The decline of sea otters followed a decline in harbour seal and Steller sea lion populations, the killer whale’s preferred prey,[Note 1] which in turn may be substitutes for their original prey, now decimated by industrial whaling.

In steeply banked beaches off Península Valdés, Argentina, and the Crozet Islands, killer whales feed on South American sea lions and southern elephant seals in shallow water, even beaching temporarily to grab prey before wriggling back to the sea. Beaching, usually fatal to cetaceans, is not an instinctive behavior, and can require years of practice for the young. “Wave-hunting” killer whales spy-hop to locate Weddell seals, crabeater seals and leopard seals resting on ice floes, and then swim in groups to create waves that wash over the floe. This washes the seal into the water, where other killer whales lie in wait.

Killer whales have also been observed preying on terrestrial mammals, such as deer and moose swimming between islands off the northwest coast of North America. Killer whale cannibalism has also been reported based on analysis of stomach contents, but this is likely to be the result of scavenging remains dumped by whalers. One killer whale was also attacked by its companions after being shot. Although resident killer whales have never been observed to eat other marine mammals, they occasionally harass and kill porpoises and seals for no apparent
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A preview of The End of America, the Channel 4 TV documentary (first broadcast in Britain in 2000) based on my book, Life On Mars, about my move to South Beach in Miami in the 1990s. Directed by Laura Ashton, the documentary features music by Andrew Hale and songs written and performed by John Hood.
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Most Amazing Moments National Geographic #Mind Blow (Full Documentary)

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Cave People of the Himalaya | National Geographic Documentary

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The BEST channel for all your Space & Universe, Science, Technology and Nature documentaries, all in HD! Weekly updated! So keep an eye on this channel and don’t forget to subscribe! All video will be 720p at least, HD guaranteed!

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Lake Mead National Recreation Area Las Vegas, Nevada USA | Travel videos Guide

Lake Mead National Recreation Area is a U.S. National Recreation Area located in southeastern Nevada and northwestern Arizona. Operated by the National Park Service, Lake Mead NRA follows the Colorado River corridor from the westernmost boundary of Grand Canyon National Park to just north of the cities of Laughlin, Nevada and Bullhead City, Arizona. It includes all of the eponymous Lake Mead as well as the smaller Lake Mohave – reservoirs on the river created by Hoover Dam and Davis Dam, respectively – and the surrounding desert terrain and wilderness.[4] More info visit: http://en.wikipedia.org/wiki/Lake_Mead_National_Recreation_Area

Lake Mead National Recreation Area
Lake Mead National Recreation Area Las Vegas, Nevada
Lake Mead National Recreation Area Las Vegas, Nevada USA
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