Plant-eating fish control the spread of seaweed and algae on coral reefs. New research explaining why populations of these fish vary from site to site could lead to better reef protection strategies.
How you tell one whale shark from another? Spots and stripes.
Cool-water kelp forests are being eaten by tropical species moving south on warming waters.
Scientists think the European eel spawns thousands of miles away in the Sargasso Sea – but no one has ever seen an eel there.
Most ocean species start out as larvae drifting with currents. Using underwater robots, scientists have found that larvae use swimming motions to affect their course and reach suitable places to grow.
Marine parks need to cover large swathes of ocean, but they also need to cover the right areas if they are to deliver the best conservation. New research off Australia's northwest suggests how.
Tiny animals along for the ride, called epibionts, could be used as living data-loggers. Researchers can glean info from them that could help inform turtle-friendly fisheries management decisions.
Could this new technology do for the microscopic marine world what the first telescopes did for the heavens above?
A 10-week surge in ocean temperatures off the Western Australian coast has killed off large patches of kelp forest, the "biological engine" of Australia's southern reefs.
'Smell-free seas' would be a disaster for marine life.
What scientists first thought was an ancient species that had survived undiscovered for many millions of years, turns out to be part of something equally mysterious.
An estimated one-third of corals have now died in the parts of the Great Barrier Reef hit hardest by bleaching, meaning recovery could take years or even decades.
New research suggests turtle hatchlings work together with clutch mates to escape their underground nests.
The next cancer breakthrough could be found in international waters – but who's in charge of the high seas?
The Great Barrier Reef might get all the attention, but what about our western coral reefs? Warmer waters and human impacts mean these reefs are in trouble.
The 2011 Japan tsunami illustrates how more marine creatures are crossing the oceans than ever before - and not all of them are friendly travellers.
Many corals can't make it through the bleaching events caused by warming ocean waters. But some can – and scientists are trying to learn more about the sources of their resilience.
Much of what we know about these elusive eels' life cycle has been based on circumstantial evidence. Now for the first time, scientists tracked an adult eel to its distant spawning ground.
Fish numbers are rapidly dwindling globally, and fishery subsidies are one of the key drivers behind this decline.
Blue bottles have been washing up on beaches lately, but what exactly are they? And are you really supposed to pee on their stings?