Many Caribbean reefs are now dominated by sponges.
Marine sponges are ancient organisms that have survived mass extinctions. Many are more tolerant of climate change and may dominate over corals in future reef systems.
Some fish fared better than others amid the extreme temperatures of the 2016 heatwave.
Rick Stuart-Smith/Reef Life Survey
The 2016 heatwave that caused mass bleaching on the Great Barrier Reef didn't just kill corals - it also significantly changed the makeup of fish communities that call these reefs home.
Corals near Lizard Island on the northern Great Barrier Reef experienced some of the worst bleaching in 2016.
XL Catlin Seaview Survey/AAP Photo
The 2016 bleaching on the Great Barrier Reef was the worst on record. Now a new analysis points the finger squarely at human-induced warming, and warns that the entire reef's future is at stake.
A volunteer diver surveys marine life at Lord Howe Island.
Rick Stuart-Smith/Reef Life Survey
Reef Life Survey, a citizen science project where hundreds of volunteer scuba divers survey thousands of ocean sites, has revealed new insights into marine mysteries.
How the Great Barrier Reef can be helped to help repair the damaged reef.
Corals on the Great Barrier Reef that are tolerant to warmer waters can be used to help repair other parts of the reef damaged by recent coral bleaching events.
The extent of future coral bleaching is likely to vary from place to place.
AAP Image/Bette Willis
Regional variations in sea temperature can make all the difference between a coral reef suffering major bleaching or surviving as a refuge for corals, new research shows.
A taste of things to come? Storm damage on Sydney’s northern beaches in 2016.
The ocean warming that might increase the threat of a catastrophic storm could also create the conditions for a natural defensive barrier.
Regional solutions can spread across the planet.
Whitespotted surgeonfish (
Acanthurus guttatus), found in the Indo-Pacific, crop the upper portion of algae while feeding, preventing macroalgae from becoming established on reefs.
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.
A mass proliferation of
Noctiluca scintillans, a red tide forming dinoflagellate at Clovelly Beach, NSW. It can form dense aggregations that deplete oxygen and produce ammonia.
They give us part of the air we breathe but microscopic phytoplankton can also be toxic. They are also on the move thanks to climate change so a new Australian database hopes to monitor any changes.
Antarctica’s delicate ecosystem could be under threat from invasive species.
A warming Earth could see invading species arrive in Antarctica via the floating "taxi service" of the sea. That could be a threat to the southern continent's delicate ecosystem.
The third global bleaching event is currently underway but new research has revealed mechanisms that boost coral resistance to heat stress. Copyright: XL Catlin Seaview Survey.
Corals are under threat from warming seas, and new research shows that even the toughest corals will suffer.
Soon the oceans will be too warm to support thriving coral reefs.
USFWS - Pacific Region/Flickr
Corals are experiencing only the third global bleaching event in recorded history, caused by warming seas. But worse is yet to come.
Acehnese fishers are among the quarter of the world’s population who live on the coast, and for whom climate-driven changes to the oceans would make life much harder.
Hotli Simanjuntak/EPA/AAP Image
Failing to stick to the world's agreed global warming limit of 2C won't just affect the atmosphere - it will play havoc with the oceans too, potentially ruining ecosystems on which much of humanity depends.