In this episode, Doc Gruber and a colleague are testing a shark repellent. If effective, it could help save the lives of divers, swimmers and surfers all over the world.

Here's some more stunning underwater footage. This time it's hammerhead sharks and stingrays, a wahoo and some striped eels, all filmed near the Cocos Island in the Caribbean. Take a look!

Samuel Gruber's team films white-tipped sharks and barracuda feeding at night off Cocos Island. Enjoy!

Plastic pollution poses one of the biggest known threats to the ocean and all related ecosystems. Pollution comes in many forms, and agriculture is one important key to bringing about necessary change. All of us are key players, since we all eat food.

Merve feels lucky to live in Kamloops, a small city in southwest Canada, and you can see why! It’s a beautiful place, surrounded by wilderness on all sides. Merve tells us about the area's mountains, grasslands, rivers and lakes, the gold rush of the late 19th century, and its wealth of fascinating wildlife.

In this beginner-level video, Luana teaches us about plants. She talks about the functions of the various parts of a plant, and offers tips on watering plants that grow indoors and outdoors.

Here's the trailer for an inspiring film about the efforts of ordinary people to make the world a more sustainable place. Experts talk about the necessity of taking action.

John talks about the importance of the city park, no matter how small, in the modern world. He enjoys the open space, fresh air, and sun on his face. He also likes the changing seasons, which mark the passing of time.

Interview by Sustainable Coastlines for Love your Coast: a collaborative ongoing project aimed at protecting and regenerating coastlines. Footage taken in Hawaii by Jack Johnson and his team in November 2010. Music: "Flake" by Jack Johnson

This video takes a look at hydrothermal vents and the novel life forms that thrive there in the absence of sunlight, fueled by underwater volcanoes. One of these harsh environments is the Axial Seamount off the West Coast of the United States.

We all know that crows are smarter than the average bird, but will 007 be able to solve the complex puzzle and retrieve his reward?

Just how smart are dolphins? Can they tell their own reflection apart from another dolphin? Here we see examples of "self-directed" behaviors that answer this question.

This is a travel video exploring a part of Somerset, a county in southwest England. It's an ideal vacation spot for people interested in walking, cycling, and eating the delicious local cheese in Cheddar.

Meet the captain of the environmental group Greenpeace’s recently launched ship “The Rainbow Warrior III”. He describes the vessel, his love for sailing and his commitment to preserving our planet. Enjoy!

The Great Barrier Reef is the world's largest coral reef system and one of the most diverse and rich ecosystems on the planet. It is now in great danger, as the Australian and Queensland governments are giving coal companies permission to dig up coal and ship it out through the Great Barrier Reef.