Fish
There's a peculiar fish in the Venezuelan mountains that climbs boulders with its mouth – and biologists are obsessed with it
Researchers believe the animal – which lives in the mountains east of the Orinoco River – is the missing link between two strange fish families.
Fish Doorbell: the underwater livestream saving fish in the Netherlands
What is the Fish Doorbell and how is it helping local wildlife? Dive in for the full story...
It barks like a dog, has razor-sharp teeth and is a horror movie favourite – but is this scary-looking fish just misunderstood?
It's been made famous in horror films for its ferocious nature, but is this creature really that deadly? We find out once and for all.
Expedition team has "unforgettable encounter" with one of New Zealand's most remarkable creatures
Researchers have captured footage of nearly 30 New Zealand longfin eel ahead of their 1,000-mile migration to Tonga. After their epic journey, the eels lay their eggs and die – but how do the young get back home?
These divers spent 12 days carrying bags of shrimp and staring at fish in the Mediterranean Sea – here's why
The researchers wanted to find out if wild fish can recognise individual human beings – so, can they?
Electric organs, venomous spines and eyes that migrate – meet the world's most peculiar fish
These ambush predators can also create a vacuum that sucks prey right into their mouths.
This may be the most astonishing ambush attack you'll ever see
The zebra shark didn't see this coming...
This new species has been named after a character from Studio Ghibli – here's why
Chinese researchers have discovered a new fish species, naming it after a Studio Ghibli character because of its face paint-style markings
How an electric eel works and the maximum shock it delivers... (you wouldn't want to be be hit by its deadly high-voltage charge)
Did you know electric eels can produce a hefty shock of 600 volts if needed? Matt Doggett take a look at how and why electric eels produce electricity
Is there really no such thing as a fish?
It's a saying you might be familiar with, particularly if you listen to the popular podcast by the QI Elves, but how true is it? Is there really no such thing as a fish?
A great predator is slipping through a hidden passage into the rivers and lakes of Alaska
The long, slender hunter has razor-sharp teeth and poses a threat to native wildlife, say researchers.
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...