Top 10 Viral Animal Videos of the Year

We laughed, we gasped, and we learned from these videos in 2015.

Over the past year we’ve shared some great viral videos from around the Internet, including a few that were created by National Geographic staff, explorers, and partners. Many of these videos featured animal behaviors that were relatively unknown and surprising.

Human beings share the planet with hundreds of thousands of other species. Although many have been named and characterized by scientists, there are still many things experts can’t yet explain. At the same time, the proliferation of smartphones and affordable video cameras has brought an avalanche of new recordings of natural phenomena, some never previously documented.

This wealth of content has also raised new ethical questions. How do we know a video is real and not altered in some devious way? Did the person doing the filming cause harm by their actions or by their very presence? Does spreading word of a rare animal put it at risk from poachers or others? Is a behavior being taken out of context, resulting in misinformation and fear?

There aren’t easy answers to these questions, although in our reporting we’ve done our best to verify what we cover, provide multiple viewpoints, avoid harm, put things in context of science and conservation, and be transparent.

With those things in mind, we look back at the most popular viral videos we covered in 2015:

One of our most popular stories of the year dealt with a fairly recent viral trend: scaring pet cats with cucumbers. Although some cats don’t seem to react to a clandestinely placed vegetable, others leap into the air, as if they’re terrified of an intruder.

Cat behavior experts say the cats are responding with a natural defensive impulse, as if encountering a potential predator. The experts also advised against trying it at home for fear of stressing out pets without good reason. That advice inspired a vigorous debate among our readers and online.

Paddleboarders off a popular beach in Southern California recorded an encounter they had this summer with a group of juvenile great white sharks, riveting the Internet and drawing criticism from viewers who thought the paddlers should have headed for shore at the sight of sharks.

A great white shark expert we spoke to said the juvenile fish were likely curious but not dangerous, although he cautioned that it’s best to leave wild sharks be.

Deep Blue (The biggest shark ever filmed) second part

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Another popular viral video from this summer showed “Deep Blue,” a 20-foot (6-meter) long great white. The video was made by a biologist and diver off Mexico’s Guadalupe Island.

The scientist thinks the shark may be the largest ever filmed. The animal was also most likely pregnant, further suggesting that the species is making a slow recovery, after years of declines due to overfishing.

Watch this incredible footage of Dottie the female Texas Barn Owl defending her nest against a snake that attempted to...

Posted by Bird Cams on Friday, May 8, 2015

In May we shared a video of a Texas barn owl defending her nest and owlets from an invading snake. The video was captured on a livecam set up by the Cornell Laboratory of Ornithology.

“All of us here were pretty impressed with the reaction of the female owl, of the decisiveness and accuracy of her first disabling strike on the snake,” said Cornell’s Charles Eldermire. “And of course [we were] relieved when the snake was evicted from the box.

A video uploaded to YouTube in May shows a retired circus lion named Will experiencing the feel of grass for the first time, in a sanctuary in Brazil. (Learn about the retiring of circus elephants.)

“That video made my day,” one commenter wrote.

Another video of a mother protecting her young from predators was uploaded in June. It shows a cottontail battling a black rat snake. A biologist says the rabbit tried to disembowel the snake.

“Not so cute and cuddly, are they?” said Dana Krempels of the University of Miami.

In this video from May, a hiker in Sweden scares off an approaching brown bear by shouting and making himself look bigger.

That’s a good idea, experts say, as is hiking with a buddy and making noise to avoid startling dangerous animals.

National Geographic Emerging Explorer David Gruber discovered a biofluorescent sea turtle near the Solomon Islands and shared it in this exclusive video. The critically endangered hawksbill sea turtle was glowing red and green and is the first reptile scientists have seen exhibiting biofluorescence—the ability to reflect the blue light hitting a surface and re-emit it as a different color.

"I've been [studying turtles] for a long time and I don't think anyone's ever seen this," says Alexander Gaos, director of the Eastern Pacific Hawksbill Initiative, who was not involved in the find. "This is really quite amazing."

Scientists have yet to explain why the turtle was glowing or how widespread the behavior is, although they have also identified it in loggerhead sea turtles. (See their recent paper.)

In a YouTube video that went viral this summer, an octopus trudges along the ocean floor carrying two halves of a coconut. Suddenly it stops, pulls them together and climbs inside.

The behavior has touched off a debate among scientists about whether it constitutes true tool use. A more important question is whether the mollusk also put some lime in that coconut.

In July, camera-trap footage revealed a genet “riding” on the back of a black rhinoceros in South Africa. The mongoose relative was likely searching for food, says Craig Sholley, a wildlife biologist and vice president of the African Wildlife Foundation. That includes insects disturbed by the heavy rhino and parasites on the larger animal.

The rhino may also offer a perch from which the genet can scan for prey or avoid predators.

With the increase in use of camera traps by scientists, photographers, nonprofit groups, and even hobbyists, such unusual interactions are more likely to be documented.

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