South Coast Algal Bloom

The Hon. T.A. FRANKS (15:49): 'After almost 100 years on the planet, I now understand the most important place on Earth is not on land, but at sea.' So said Sir David Attenborough recently. The algal bloom of Karenia mikimotoi, which persists in waters off South Australia's coast, has now been with us for over two months. Indeed, many South Australians will have lamented its impact on their recent school holidays. These too fell during a period of warmer than usual weather, one which continues to this day, an unmistakable impact of climate change.

This algal bloom is with us because of climate change. Reports of something being not quite right in the waters off our coast first began to appear in early March. Since then, we have seen so many reports of the death of aquatic wildlife off our coast. Human health has also been hit, with reports of irritated skin and eyes and flu-like symptoms. Unlike other animal species, though, we have been able to avoid, reduce or minimise our exposure to the algal bloom. Aquatic species in particular, of course, are less fortunate.

The breadth of aquatic species impacted is astounding. Some of the earliest to be found dead on our beaches in unusually high numbers were leafy sea dragons, our state's marine emblem. The leafy sea dragon is listed as near threatened. By late March, the cause had been identified by a lab at UTS and has now been confirmed, with the diagnosis being made by multiple other labs. Dead octopi were next to be reported, in this instance on Basham Beach at the beginning of April. They were followed by seals and thousands of pipis at Goolwa. Early May saw sharks and rays dead along the beaches of the Yorke Peninsula and a great white shark dead on the foreshore of Henley Beach in metropolitan Adelaide just a few weeks ago.

This is only what we are seeing on our beaches. Chances are that there are much higher numbers of dead aquatic animals littering the sea floor. It is not unreasonable to expect that species of all sorts will have been impacted and that recovery is a long-term proposition, with a quick bounce back highly unlikely. We now know the algal bloom is approximately the size of Kangaroo Island and nearly 20 metres deep. For those of you trying to do the mental gymnastics and work that out, Kangaroo Island is some 4,374 square kilometres. Algal blooms such as this are brought on by increased temperature, rainfall, or lack thereof, reduced water quality and elevated levels of pollutants.

While I cannot comment on the levels of pollution in the waters off our coast, we have had warmer than usual temperatures and we have certainly had decreased rainfall. One of the impacts of climate change is of course warmer ocean temperatures, and while we see elevated temperatures on land and suffer their impacts, it is our oceans, mostly out of sight to us, that will bear the brunt of climate change. They absorb, as the Deputy Premier recently reminded us in the other place, 90 per cent of the global warming that has occurred in recent times. Warmer oceans are more acidic and carry less oxygen. One of the flow-on effects of this is a reduced mix of oxygenated water at the surface with the waters which naturally contain less oxygen.

The vast majority of the species impacted by the algal bloom are species which live in seagrass beds or shallow sandy areas. These are the least able to move away from conditions such as this and, when we take into account the size of the bloom, have little or no chance of moving the kind of distance they would need to to escape the bloom, even if their gills were not impacted as they are by the bloom itself. The scientific studies proved conclusively that after 3½ hours of exposure to Karenia mikimotoi, more than 80 per cent of fish gill cells had died. It is hard to see how any species with severely reduced lung capacity in water with lower than usual oxygen levels could survive for long, let alone travel the large distances they would need to do to recover.

So where to from here? Whilst we are told there is nothing we can do except wait, in this particular circumstance, for weather conditions to change and disperse this bloom, it is obvious we need to throw everything we have at climate change, and that part includes better resourcing of our departments such as DEW and PIRSA so they can respond quickly to identify the causes of outbreaks such as this.

Governments do not have to go it alone, of course, and citizen scientists and professional scientists are ready, willing and able to assist, as they always have been, but we could amplify their contribution if better access was available to the data and the testing results in a more transparent and timely way. With that, community trust will be bolstered if we have the transparency that we need for the scientists to get on and do their jobs.