Bass Strait

• And if you’re fishing off Sydney and catch a tropical coral trout, you might wonder what’s going on.
• The ocean has absorbed the vast majority of the extra heat trapped by carbon dioxide and other greenhouses gases.
• It’s no wonder heat in the oceans is building up rapidly – and this year is off the charts.
• In Australia, at least 200 marine species have shifted distributions since 2003, with 87% heading south.

Here are eight species on the move

• Branching coral (Pocillopora aliciae) Historic range: northern NSW Now: Look out for this pale pink beauty south of Port Stephens, not far from Sydney.
• Seemingly immovable species like coral are fleeing the heat too.
• They’re already providing habitat for a range of other shifting species like tropical fish and crab species.
• Look for red, threadfin, and redthroat emperors in southwest WA as the Leeuwin current carries these warm water species south.
• As WA fisheries expert Gary Jackson has said, this current is a warming hotspot, acting like a warm water highway for certain marine species.
• That’s bad news for kelp forests and the species which depend on them.

You can help keep watch

• If you spot a creature that wouldn’t normally live in the waters near you, you can upload a photo to log your sighting.
• For example, avid spearfisher Derrick Cruz logged a startling discovery with Redmap in 2015: A coral trout in Sydney’s waters.
• As he told us: “I’ve seen plenty of coral trout in tropical waters, where they’re at home within the coral.
• But it was surreal to see one swimming through a kelp forest in the local waters off Sydney, much further south than I’ve ever seen that species before!” How does tracking these movements help scientists?