An enormous algal bloom has invaded the South Australian coast. It is caused by the micro-algae Karenia mikimotoi, setting in motion one of the most unique and severe environmental disasters ever documented. What began as March’s small outbreak has since expanded to over 10 times that size—nearly the area of Kangaroo Island! It is sometimes associated with the deaths of hundreds of marine animals. With that war raging on land, experts are sounding the alarm for beachgoers to steer clear of contaminated waters.
The present marine heatwave, in concert with extraordinary ocean calm, has played a role in the bloom’s disturbing expansion. In addition, for the entire region, water temperatures are running about 2.5 degrees C above normal, a signature of long-term warming trends resulting from climate change. In places, this toxic algal bloom extends down as deep as 20 metres.
Scope of the Bloom
Dense foam and hundreds of dead marine animals surged onto beaches at Waitpinga and Parsons Beach on South Australia’s Fleurieu Peninsula. This eye-popping scene was the first news of the tide’s scary spread. Since then, carcasses of wildlife have been reported all over Kangaroo Island, Yorke Peninsula and many beaches south of Adelaide.
Environment Minister Susan Close asserted that the bloom’s record size is causing serious dangers to local ecosystems. She stated, “This is a larger bloom than has ever been seen before.” The extraordinarily out-of-whack state of affairs has sparked deep concern for the safety of marine life. It further threatens beachgoers who could be exposed to toxic algae.
“If you see that there is scum on the beach, if you see that there is discolouration in the water – stay away, don’t go in,” – Susan Close
Impact on Marine Life
The consequences of the bloom are severe. What we’re seeing is masses of dead marine life washing up on nearly every beach from Florida to Virginia. Just last week, a white shark washed up dead on Henley Beach. Our researchers are working hard to understand how this shark died. In April, they had already reported two other sharks dead at Port Willunga and Port Moorowie.
According to Dr. Mike Bossley, a marine biology expert with a deep understanding of marine ecology, the microscopic algae can be extremely dangerous. He described how these toxin-producing organisms can cover fish gills, causing suffocation and increased mortality with flipping and abnormal behavior.
“These microscopic algae can coat the gills of fish and it could be that they are basically being suffocated … that’s what’s causing them to act in strange ways,” – Dr Mike Bossley
Woman who was assessing the effects of the algae bloom on the Yorke Peninsula, attacked by eagle ray. This incident is yet another reminder of the strange behavior of marine animals during this unprecedented crisis.
Safety Precautions for Beachgoers
The present algal bloom is raising alarming risks to sea life as well as human beings. Environmental and health experts are advising caution for those who might visit contaminated beaches. Dr. Bossley discouraged entering waters with algae blooms, pointing out that it can be life-threatening.
“I would recommend people give careful thought to whether they go in the water where the algal bloom is happening … it’s quite dangerous,” – Dr Mike Bossley
Minister Close reiterated these warnings, advising that beachgoers shower off everywhere after coming in contact with possibly contaminated water.
“And if you have been in, wash yourself down thoroughly,” – Susan Close
Residents and visitors alike are contending with an unparalleled experience. As officials have pointed out, persistent, strong westerly winds will likely be key to dispersing the algal bloom.
“The only thing that is going to break this algal bloom up is a change in the weather and starting to get strong westerly winds,” – Susan Close
