The latest State of the Environment report paints a "particularly grim" picture for Western Australia, according to scientists, with mammal extinctions, bushfires and water availability highlighted as key areas of concern.
Written by independent scientists from around Australia, the report found all aspects of the Australian environment were under pressure, and most were declining.
This was due to climate change, habitat loss, invasive species, pollution and resource extraction.
The report looked at the environment through a national lens.
But Curtin University botanist Kingsley Dixon, who was a contributing author of the report, said there were several specific and alarming observations for WA highlighted in the report.
He said one of the key concerns related to the rate of mammal extinctions.
“We’re just 9.6 per cent of the population and yet we've got a third of the mammal extinctions alone in the state,” Professor Dixon said.
Over the past two centuries, Australia has lost more mammal species than any other continent, according to the report.
It said that, of the 20 mammal species most at risk from extinction over the next 20 years, most were from northern Australia and south‑west WA.
Professor Dixon said it was crucial to turn this around.
"South-west WA is one of the richest places for unique animals, plants and bushland areas [in the state]," he said.
Professor Dixon said the report showed there had been no progress in the past five years.
"This is a wake-up call for WA, that 'business as usual' is not appropriate and [we] can't keep going the way we are for the next five years if we are to alter the way the environment of WA will be sustained into the long term, particularly with climate change," he said.
Water availability and extinctions
Another key observation for WA was declining — or shifting — water availability, and salinity issues due to climate change and clearing.
Dryland salinity adversely impacts agriculture and available water resources, as well as biodiversity and wetlands.
The report found freshwater streams and rivers have become increasingly saline, and said that south‑western Australia was particularly affected by salinity.
It referenced a 2018 review that found government agencies had failed to prevent and mitigate land degradation throughout the south‑west.
Declining ground water availability was also flagged, particularly for WA with the Gnangara groundwater system Perth's lowest‑cost and largest source of good‑quality water.
"In south‑west WA, groundwater levels have generally been declining for the past 40 years as a result of decreasing rainfall coupled with increasing groundwater demand," the report said.
However, it said, groundwater trends in the previous five years have been mostly stable, with measures to reduce and redistribute groundwater extraction undertaken.
In June, the WA government released the new Gnangara groundwater plan, which aims to improve declining groundwater levels in Perth.
Increased climate extremes and emergencies
The report said climate change was increasing the risk of more intense and more frequent weather extremes, including bushfires, droughts and floods.
It said rainfall had decreased in south-west WA since the 1970s, and increased in north-west Australia over the same period, with indications of shorter but more intense rainfall events.
"Although Australia is no stranger to extreme events — such as tropical cyclones, hailstorms, blizzards, flooding rains, storm surges, heatwaves and bushfires — climate change is affecting the frequency, intensity and distribution of these events," the report noted.
"[It's] even creating new forms of environmental impact — for example, fires that increase lightning strikes from the firestorms they create, and smoke‑induced oceanic phytoplankton blooms."
It is a threat well known to WA's State Emergency Services.
DFES commissioner Darren Klemm said he had not had an opportunity to read and digest the report yet, but he would in coming weeks.
"We will check things out and check it against our current predictions, with a clear focus to keep the community safe," he said.
The state government is reviewing WA's bushfire planning, and building frameworks to ensure plans are based on scientific evidence and adapted to the state's landscapes and its bushfire risks.
Marine life and ecosystems under threat
The state's marine ecosystems are in one of the few categories assessed as being in good, stable condition.
Increases in the biomass of both phytoplankton and zooplankton have been reported since 2016, according to the report.
But Curtin University coral taxonomist Zoe Richards, who contributed to the report, said the overall picture for WA’s coral reefs was not positive.
"WA used to fare quite well, especially with the marine ecosystems, but these days the same impacts that were affecting the eastern states are starting to impact the west coast," she said.
She said one of the most shocking events of the past five years was the 2016-17 widespread coral-bleaching event, which drastically impacted the Scott Reef ecosystem.
Dr Richards said the report showed that small, local actions — such as cleaning up water quality — could be successful.
But she said the outcomes largely boiled down to climate change.
"Hopefully, this report — and this very dire picture that it paints for all ecosystems — will be impetus enough for our government to finally enact solid and ambitious actions to curb these problems and protect our incredible native fauna that we have in Australia," Dr Richards said.
