The testing, conducted by the Department for Environment and Water (DEW) and Department of Primary Industries and Regions (PIRSA), shows the algae is present in the Coorong North lagoon between Seven Mile Basin and Long Point.

Experts believe the current Karenia algae strain flowed through the Murray Mouth and into the lagoon during the May 26 storm and May 27 high tide.

Further testing will be undertaken to determine the specific Karenia strain.

The Karenia mikimotoi algae has been detected in numerous locations along the Fleurieu Peninsula, Yorke Peninsula and Kangaroo Island since March this year.

Water testing in the Coorong will be undertaken weekly to understand how the situation is developing and to inform any potential future management options.

The composition of the Coorong means that it flows naturally to the open Murray Mouth and vice versa when high ocean tides can enter the lagoon.

This current algal bloom is constantly changing, meaning that its spread and dissipation is dictated by the weather and ocean conditions.

The dynamic nature of the algae means its effect on people, coastal industries and the ecosystem is unpredictable.

Unfortunately, there is no feasible method to dilute or dissipate the bloom. However, Government agencies, including DEW, PIRSA, the Environment Protection Authority (EPA) and SA Health continue to monitor the situation.

SA Environment Minister Susan Close said the outbreak followed three key events.

In 2022/23 the state experienced flooding along the River Murray, which saw run-off enter the Southern Ocean. . . .

After that, in 2023/24 a cold upswelling brought nutrient rich water to the surface.

And in September 2024, a marine heatwave began, which saw temperatures 2.5 degrees Celsius above normal levels.

On March 15, surfers and beachgoers reported illnesses after visiting Waitpinga Beach on the Fleurieu Peninsula.

By March 16, a brown foam and dead sea life were found on the beach, marking the beginning of a months-long crisis along SA's coastlines.

Dr Close said all of those events could be attributed to climate change. . . .

Karenia mikimotoi doesn't actually produce a toxin but it does produce what's called reactive oxygen species so this can damage the gills of fish and it can affect skin cells," she said.

"What this damaging the gills of the fish means is marine animals basically drown if their gills become too damaged."

Other dead sea mammals have been found dead along the coast, including dolphins and sea lions.

The official advice is that Karenia mikimotoi isn't toxic to mammals.

The government said it was not uncommon for marine mammal carcasses to wash ashore after winter storms.

SA authorities are performing autopsies to determine the cause.




According to the latest science, nothing can be done to dilute or dissipate the bloom.

When it first appeared, scientists predicted a cold winter front would help dissipate it.

But the ongoing marine heatwave and drought conditions meant rain did not arrive until winter, and the storm fronts have done little to hamper the bloom so far. . . .

What has the impact been?
The bloom has killed thousands of sea creatures, decimated local sea habitats and has spread at an unprecedented level.

It has had a huge impact on commercial fishing, tourism and other businesses who operate in or near the sea.

So what's next?
Flinders University Associate Professor of Natural Sciences (Oceanography) Jochen Kaempf has developed a computer model to predict where the algae will spread next.

While awaiting peer review, the model predicts the bloom will ease over winter, but worsen next summer.

"There is nothing you can actually do to prevent it. The only thing you can do is you can hope that there is enough of the zooplankton, which are swimming, small marine plankton that actually eat, take up enough of the algae so that it can't re-evolve in the next summer when the water gets warmer again," Professor Kaempf said.

"The only thing that can actually only clear it up is if it's consumed, if it's eaten by other marine organisms of the food chain."So what's next?
Flinders University Associate Professor of Natural Sciences (Oceanography) Jochen Kaempf has developed a computer model to predict where the algae will spread next.

While awaiting peer review, the model predicts the bloom will ease over winter, but worsen next summer.

"There is nothing you can actually do to prevent it. The only thing you can do is you can hope that there is enough of the zooplankton, which are swimming, small marine plankton that actually eat, take up enough of the algae so that it can't re-evolve in the next summer when the water gets warmer again," Professor Kaempf said.

"The only thing that can actually only clear it up is if it's consumed, if it's eaten by other marine organisms of the food chain."

[url]https://en.wikipedia.org › wiki › Leafy_seadragon[/url]
The leafy seadragon (Phycodurus eques) or Glauert's seadragon, is a marine fish. It is the only member of the genus Phycodurus in the family Syngnathidae.[/size] Photo.

Description
A photosynthetic species with several oval to round yellow-brown chloroplasts, each with a pyrenoid. The large ellipsoidal nucleus is located in the left hypothecal lobe. No thecal plates are present. Cells are small, broadly oval to almost round and compressed dorso-ventrally. Cells are slightly longer than wide with a characteristic long and straight apical groove to the right of the sulcal axis. The apical groove extends from the ventral side to the dorsal side of the epitheca creating a slight indentation at the apex of the cell. Cells range in size from 18-40 µm in length to 14-35 µm in width .The epitheca is broadly rounded and smaller than the hypotheca. The hypotheca is notched by the widening sulcus at the antapex resulting in a lobed posterior. The wide and deeply excavated cingulum is pre-median, and is displaced in a descending spiral about 2 times its width. The sulcus slightly invades the epitheca extending from above the cingulum to the antapex (adapted from http://www.nmnh.si.edu/botany/projects/dinoflag/Taxa/Gmikimotoi.htm).

Habitat
A planktonic species first described from western Japan. This species is a recurring bloom former in coastal waters of Japan and Korea; red tides commonly occur in warmer months and are associated with massive fish and shellfish kills. Reported to be eurythermal¹ and euryhaline², populations of G. mikimotoi could presumably over-winter as motile cells, which could then serve as seed populations for a summer red tide. Moreover, studies conducted in Omura Bay, Japan, revealed that this species can tolerate anoxic³ or near anoxic conditions utilizing sulfide from the sediment.

Key Characteristics
Cells have a distinct swimming pattern: turning over through water, like a falling leaf.

Created: 26 April 2002 by M.D. Guiry.

Last updated: 28 May 2024