Australia's environment is improving, but climate change is 'accelerating' damage to marine ecosystems and wildlife

Australia's environment experienced above average conditions for the fifth consecutive year in 2025, but climate change continues to inflict "serious and accelerating damage" on marine ecosystems while driving more species toward extinction, according to the 2025 Australia's Environment Report, led by The Australian National University (ANU) in collaboration with TERN.

The report found the number of species listed as threatened under federal law has grown to 2,175—a 54% increase since 2000, with 39 new listings in 2025.

Meantime, sea surface temperatures around Australia reached its highest-ever recorded level in 2025.

The report also found that heat stress across 79% of satellite-monitored reef locations around Australia exceeded their once-in-a-decade threshold—more than any previous year in the 40-year record.

This led to a sixth mass bleaching event on the Great Barrier Reef, while a toxic algal bloom driven by warm waters spread across nearly a third of South Australia's coastline. The algal bloom, which persisted for most of the year, killed countless animals and impacted the health of coastal residents and beachgoers.

"Despite good rainfall across most of Australia improving soils and vegetation, marine ecosystems and wildlife continue to bear the cost of a warming climate," the report's lead author ANU Professor Albert Van Dijk said.

"These extreme marine heat waves are the underwater equivalent of the Black Summer bushfires—large-scale, climate-driven mass mortality events that used to be rare but are now happening more often."

In 2025, Australia's environment scored a 7.4 out of 10 at the national scale, marking the fifth consecutive year of above average conditions. The four years prior saw the country score between 6.5 and 8.5 out of 10, after extremely low scores between 0.4 and 2.0 out of 10 in the disaster years of 2019 and 2020 during the Black Summer bushfires.

According to Professor Van Dijk, Queensland had a "standout" year in 2025, with exceptional rainfall and extensive wetland flooding carrying the state's score to 8.3 out of 10.

"Conditions also improved in South Australia and Western Australia in 2025. But parts of southern and southeastern Australia endured a third consecutive dry winter, with notable score declines in Victoria, Tasmania and the Australian Capital Territory, as well as in the Northern Territory," he said.

"A highlight of the year was the spectacular filling of Kati Thanda–Lake Eyre. Exceptional rainfall across central Queensland sent floodwaters surging through the Channel Country river systems in the most significant inundation in at least 15 years, triggering mass hatching of invertebrates, fish breeding and the arrival of waterbirds from across the continent."

Professor Van Dijk said the devastating impacts of the Black Summer bushfires continue to linger like a bad smell, accounting for more than half of all species listed or uplisted as threatened since 2019, while invasive species remain a persistent and largely irreversible pressure across the landscape.

TERN's Threatened Species Index—which tracks population trends of listed species over time—shows that threatened species have declined by an average of 59% since 2000.

New data reveals that reptiles have declined by 88% and frogs by 67% on average since 2000. This is the steepest long-term declines of any group measured to date.

"Threatened mammals fared best, with populations showing signs of stabilization in recent years, likely reflecting a combination of good rainfall and the measurable benefits of predator control and habitat restoration," Professor Van Dijk said.

"The extinction crisis is real, and it is worsening. And increasingly, climate change is the thread running through it, compounding habitat loss, interacting with invasive species, and intensifying fire. That's what makes it so hard to tackle."

However, Professor Van Dijk stresses that Australia's environment is not doomed. He says in many respects it is in better shape than it was a decade ago. But we must drastically cut emissions to prevent the worst impacts on our nation's environment and ecosystems from unfolding.

"Climate change is the threat we don't yet control, and decades of warming are already locked in. That means reducing emissions remains as urgent as ever. Managing our way through climate change will remain the defining environmental challenge of our time," Professor Van Dijk said.

Conducted annually, the report's authors analyze vast amounts of satellite station and field measurements and give the country a National Environmental Condition Score—an index tracking rainfall, river flows, vegetation, soils and temperature.

More information:
The full report and score cards for individual regions are available online at https://ausenv.tern.org.au/aer.html.

Provided by Australian National University