Species native to the Great Barrier Reef are more likely to face extinction through climate change than marine life elsewhere that can adapt by “invading” new regions, according to new research.



The largest study to date on the impacts of climate change on marine biodiversity found that many species would cope by finding new waters.

However, tropical species with narrower ranges were more likely to die out in a rapidly warming climate, the international research team found.

And the unknown effects of “invaders” encroaching on “natives” would pose “unprecedented challenges” for conservation, they warned.

One of the researchers, John Pandolfini from University of Queensland’s ARC centre of excellence for coral reef studies, said the richness of marine biodiversity would change markedly and vary considerably region to region.

He said the study of almost 13,000 species “gave us hope that that species have the potential to track and follow changing climates but it also gave us cause for concern, particularly in the tropics, where strong biodiversity losses were predicted”.

“This is especially worrying, and highly germane to Australia’s coral reefs, because complementary studies have shown high levels of extinction risk in tropical biotas [local marine populations], where localised human impacts as well as climate change have resulted in substantial degradation,” Pandolfini said.

The modeling relied on blending “climate velocity trajectories” – a measurement which combined the rate and direction of shifting ocean temperatures over time – with information about what temperatures and habitats species can tolerate.

CSIRO professor Elvira Poloczanska said the study showed that climate change would drive a new sameness in marine life populations across the world.

“Ecological communities which are currently distinct, will become more similar to each other in many regions by the end of the century,” Poloczanska said.

University of the Sunshine Coast researcher David Schoeman said the model suggested there was still time to prevent major climate-driven extinctions outside the tropics.

“Results under a scenario in which we start actively mitigating climate change over the next few decades indicates substantially fewer extinctions than results from a business-as-usual scenario,” Schoeman said.

However, the prospect of new blends of marine life populations through climate-driven migration was “possibly more worrying”.

“We have little idea of how these new combinations of species in ocean systems around the world will affect ecosystem services, like fisheries,” he said.

“We should be prioritising ecological research aimed specifically at addressing this question.”

Pandolfi said the broad geographic connections of climate change effects shown by the study underlined the need for international cooperation on conservation.

Climate Velocity and the Future of Global Redistribution of Marine Biodiversity is published in Nature Climate Change.