Fish
Diver films close up of a shark's extraordinarily powerful secret weapon - and it's not its jaw - when hunting prey
Thresher sharks have an unusual way of hunting prey – which means their elongated tails aren’t just for show
Why are pufferfish so deadly poisonous - able to kill a human - and how on earth do they avoid poisoning themselves?
Helen Scales takes a look at the highly poisonous pufferfish
How and why do male seahorses get pregnant?
Matt Doggett explains why it's the male seahorse that become pregnant, rather than the female
When scientists went into an underground river in the Philippines, they found a ghostly creature living in the shadows
They named the newly described animal after Hades – Greek god of the dead and king of the underworld.
Shocking, drastic decline in Mediterranean shark numbers despite protection
Shark numbers falling despite conservation efforts across Med, researchers say
Whale shark mating strategy involves aggressively stalking and biting the female, rare footage reveals - but does she respond?
Rare footage has captured an adult whale shark following and biting a female, revealingthe elusive mating rituals of the biggest fish in the ocean
With razor-sharp and a 36mph top speed, this is one intimidating, fearsome ocean predator - that has been known to attack humans
All you ever needed to know about the barracuda
Why evolution experts are so consumed by this deep-sea fish
The animal lives in almost perpetual darkness, up for 4km beneath the surface of the sea.
What's the fastest fish?
Wondering how fast fish can swim? Stuart Blackman seeks out the record breakers
Can fish drown?
Can fish drown? What about other species that spend their lives underwater? We explain the science of breathing underwater and what can go wrong
There's a shark rush hour? Yes - scientists reveal the secrets of the ocean's 'Shark Highway'
This rush hour is one you probably don't want to get stuck in
The largest dam-removal project in US history has finally been completed. Now something truly amazing is happening
Four dams were dismantled on the Klamath River – this remarkable video shows what happened when the final barrier fell...
Meet nature’s deadliest sniper: This fish shoots down prey with lethally-accurate water jets, from over 3 metres away
How do sharks mate? Shark sex is a rarely seen but lively business – here’s how they do it
Just how do sharks mate? Stuart Blackman explains
Great white shark: your expert guide to the ocean's ultimate apex predator that can detect blood from 3 miles away
All you need to know about great white sharks, including why they are not as deadly as often feared
Do fish drink water?
Do fish drink? or do they absorb water? Stuart Blackman takes a look
Meet the tiny shark that uses its saw-like teeth like a cookie cutter, ripping circular chunks of flesh from its prey
Discover the weird 'doomsday' fish, the eerie sea serpent-like monster that, according to legend, can 'foresee' deadly tsunamis
Meet the mysterious oarfish, the deep swelling sea serpent that's known as harbingers of doom”.
World's grumpiest fish discovered in the Red Sea. And scientists have given it the perfect name
At less than 2cm long, this grouchy goby is a tiny but fierce predator
There's a rare fish in the Red Sea that looks like a guitar – and it may soon be lost forever
The critically endangered halavi guitarfish could be extinct in a few years’ time if nothing is done to save it, say scientists
Why is the blobfish so ugly?
We take a look at why the unfortunate blobfish has been labelled as the ugliest fish in the world
Are rays just flattened sharks? No, say the experts at The Shark Trust, there's a bit more to it than that and rays and sharks are quite different...
Uncover the similarities and differences that set sharks and rays apart.
Watch incredible footage of a tiny flamboyant cuttlefish hatching from its egg. Is this the cutest baby fish in the ocean? It's certainly the prettiest
See the moment this ‘walking’ cephalopod takes its very first steps
Meet the eel that makes an astonishing 6,000 mile journey, from European rivers to the tropical Sargasso Sea - and back again
The incredible migrations of eels have long fascinated scientists. Phil Gates explores their epic journey and the reasons behind it