Marine biologists and environmentalists in South Australia are on red alert after a potentially catastrophic algal bloom nicknamed Karenia mikimotoi. Recent reports of illness among surfers and the subsequent appearance of yellow foam at Waitpinga Beach on March 17 have fanned their fears. The impact of the bloom on recreational activities has been profound. It has contributed to the death of millions of marine species all across the state’s coastline.
A juvenile common thresher shark that washed ashore along Moana Beach (and later Seaford). This very sad occurrence brought national attention to the dangerous effects of the bloom. Investigators found a recently deceased juvenile white pointer shark lying on the coast. Its pretty pink underside drew gasps from the thronging spectators. This shark was found at Port Willunga in April, fueling fears of what this would mean for our broader marine ecosystems.
Impact on Marine Species
The algal bloom has moved quickly beyond its initial extension. This increase led to extreme water red tide phenomenon as seen at Brown Bay close to Port MacDonnell in late April. Poo foam Easter weekend of 2021 at Knights Beach, Port Elliot. PIRSA officers encountered a harrowing scene when collecting the remains of multiple sharks. Included in that tally was a juvenile white pointer that sadly died on Good Friday at Point Willunga, and a 2.7-meter shark found near Port Moorowie on the Yorke Peninsula.
Toxicology tests are still ongoing to determine if the algal bloom was a factor in any of these deaths. The reality on the ground continues to evolve quickly. Dead sharks, rays, and other marine life continue to wash ashore due to the spread of this devastating bloom.
“But it’s quite a few washing ashore in a small time frame.” – Professor Charlie Huveeners
Rotting marine corpses often float to the shore. Callers to ABC Radio Adelaide have described many more from places such as Stansbury and Marion Bay on the Yorke Peninsula.
The Cuttlefish Crisis
One species hit hard by the algal bloom has been the Australian giant cuttlefish. These unusual events include large numbers of dead cuttlefish washed up on beaches – particularly at Victor Harbor in March. Eyewitnesses have described thousands of dead cuttlefish drifting between Kangaroo Island and the mainland. This sight made for a horrific scene for marine life supporters and scientists the same.
In one poignant instance, the bones of juvenile cuttlefish formed a heart shape on a beach, symbolizing the fragility of marine life amid ecological crises. Asher Dezsery, a longtime environmental watchdog, observed the peculiar nature of the overabundance of these deaths.
“Usually you’d see them on the beach and not worry about them,” – Asher Dezsery
Deszery said there was growing concern about this year’s cuttlefish migration to Whyalla’s cuttlefish coast. This shocking loss of life has begun to raise alarming concerns over the health of our marine environment.
Research and Community Involvement
In light of these alarming developments, marine biologists are calling for increased community involvement in monitoring and reporting marine life conditions. Brad Martin underscored the importance of a systematic method of data collection that allows for data aggregation and cross-analysis leading to more thorough insight.
“We really want to be able to take those conversations, that information and get it into a platform that can be used for analysis,” – Brad Martin
Professor Charlie Huveeners from the Southern Shark Ecology Group is busy sampling marine organisms. Coloran has been studying them for a more comprehensive understanding of the bloom’s effects. He went on to elaborate on the profound impacts this phenomenon would have on fish runs, birds numbers, mammals and more.
“Everything from recreational species being impacted through to our iconic species such as leafy sea dragons and sea devils.” – Professor Charlie Huveeners
Professor Huveeners added that by knowing what these impacts are we can better assess the condition of marine life in impacted regions. This understanding forms a unique basis for further research.
“It provides an opportunity to understand what marine life is in the area,” – Professor Charlie Huveeners
As communities deal with these worsened ecological challenges, they are increasingly forced to ask what sort of coastal environments they will be able to preserve for the future. This spate of developments is discouraging, as David Place has articulated.
“It felt like a ghost town down there,” – David Place
