One of Australia’s most unique underwater events is facing a new challenge. The Australian giant cuttlefish mating aggregation—the world’s only large-scale cuttlefish gathering—has seen the first major decline in numbers since the event was protected from commercial fishing nearly 14 years ago.

Polarization vision is used to break the countershading camouflage of light-reflecting silvery fish researchers suggest.

Humboldt Squid found to spend many hours in a band of oxygen-poor water at a depth of more than 500 m in the California current.

Squids, octopus and cuttlefish (who all belong to the phylum of molluscs) are among the most intelligent animals in the sea, and definitely the most intelligent marine invertebrates. We should in fact ask ourselves if the human mind is capable of thinking as fast as these creatures do.

An octopus at the Fitzgerald Marine Reserve in California hauls itself out of the water, and moves across land, before sliding back into the water. Octopuses do this in nature to escape predators, and also to find food of their own in tidal pools.

International researchers have collected venom from octopuses in Antarctica for the first time, and could open a new frontier in drug development and even washing detergents

Most cephalopods—the group in which scientists classify octopuses, squid, cuttlefish and nautiluses—can change color faster than a chameleon. They can also change texture and body shape, and if those camouflage techniques don’t work, they can still “disappear” in a cloud of ink, which they use as a smoke-screen or decoy.

Outsized sperm produced to thwart larger males’ chances of impregnating females.

Low frequency sound found to cause lesions in sensory organs of squid, octopus and cuttlefish

Shining Symbiosis: Bobtail squid and their bacteria buddies