In this absolutely incredible footage from EarthTouchTV, watch hundreds of thousands of sardines off the coast of South Africa swarm at the center of an animal feeding frenzy. With Earth-Touch divers right in the middle of the action, large, hungry predators — sharks, dolphins, diving gannets, and a 20 to 30 ton Bryde’s whale — all take part in this intense and fascinating sardine run.

There are hours of nature and underwater videos in the archives.

To celebrate World Ocean Day 2013, director and animator Akiko McQuerrey created a Papa Cloudy stop-motion music video: Overfishing Song from Papa Cloudy’s Restaurant.

Overfishing—catching fish faster than they can reproduce—is an urgent and devastating issue, and may be the single biggest threat to ocean ecosystems… The global fishing fleet is operating at 2.5 times the sustainable level—there are simply too many boats chasing a dwindling number of fish.

What can we do to help? With more sustainable practices, our oceans can be healthy and plentiful for everyone. Recommendations from the Monterey Bay Aquarium suggest that we select sustainable fish from restaurants and stores, and diversify the kinds of fish we eat beyond just the popular choices.

To help make these choices easier, they created a Monterey Bay Aquarium Seafood Watch pocket guide and mobile app. They even have recipes and more information about how to solve our ocean challenges.

Yay!! for clear underwater footage of unusual animals, (yes, even when they’re busy eating each other for lunch), via jtotheizzoe:

The Sea’s Strangest Square Mile

Sit back and let your eyes soak up this goggle-fogging journey to the Lembeh Strait near Indonesia by Shark Bay Films. It’s known as one of the richest homes of odd coral reef creatures on Earth.

Lightning-quick eels! Coral-colored, pregnant frogfish stuffing their bellies with wriggling prey! Baby cuttlefish!! BABY CUTTLEFISH!!!

(via kottke)

More animals with camouflage skills are hiding in the archives. Plus, cephalopods, because.

Like an elusive, caped creature in the ocean, a female blanket octopus glides through the water. We know this video is of a female of the species because she is around two meters (6.6 feet) long. In contrast, the male blanket octopus is less than 3 centimeters wide. Yes, centimeters!

Differences in males and females of a species is called sexual dimorphism, and can include size, coloring or ornamentation, form or structure, and behavior. A few examples of this include peacocks, peacock spiders, birds of paradise, lions, elk, and even humans. The BBC is a good start for further viewing.

This clip is from Oceans, a French documentary film by Jacques Perrin (released in the US by Disneynature). You can watch another clip from the movie here.

via Scientific American’s Octopus Chronicles.

Watch this BBC clip of fish and frogs living out of water, featuring the lung fish, a burrowing desert frog, and the thorny devil lizard.