South Australia’s toxic algal bloom causes ocean crisis as sea life die

Marine life off the southern Australian coast is being suffocated by a blanket of toxic algae*, which is tipped to worsen significantly as the state struggles with another stretch of unseasonably* dry weather.

The microorganism* karenia mikimotoi has grown to the size of Kangaroo Island, spreading along parts of South Australia’s Fleurieu Peninsula and the Yorke Peninsula.

One of the state’s leading voices in marine conservation has described the algae bloom as the most alarming marine event in SA’s history.

Environment Minister Susan Close told The Advertiser that higher sea temperatures – 2.5 degrees warmer than usual – combined with calm conditions and small swell had created the perfect storm for the algae to spread.

Dr Close declared the bloom “the most serious natural marine challenge we’ve had”, explaining why the algae is so deadly to sea life.

“It gets into their gills and poisons them,” she said. “Overnight the algae sucks up oxygen from the ocean and anything that’s underneath it becomes oxygen starved.

“We are seeing a lot of marine life dying and it’s disturbing and in fact distressing for people to see that.”

Despite the bloom killing marine life across the state, it is not toxic if consumed by a human.

The algae bloom is expected to worsen over the next week, with the Bureau of Meteorology* forecasting little to no rain or wind across Adelaide this week.

But Dr Close, also the Deputy Premier, was hopeful the algae would be broken up by strong winds by the end of the month.

“It’s also incredibly challenging to be dealing with a natural event that we can’t control; the lack of power that we have over ending this bloom is very distressing for people,” she said.

“This has been a really distressing and challenging experience. I’m hopeful it will come to the end in the next few weeks.”

Renowned* marine conservationist Mike Bossley said more than 50 protected sea dragons found washed up on Sunday along a stretch of Foul Bay, on the south coast of the Yorke Peninsula, was the worst impact of the bloom he has seen to date.

“I’ve been walking beaches for years and years and years, and I might see one (weedy sea dragon) every five years, but to suddenly have (52) of them washed up on one beach at one time, it’s just phenomenal,” Mr Bossley said.

“It’s alarming in both the short term, in that lots and lots of more animals are dying than we would normally see dying, but also in the longer term, we don’t know what the economic and environmental impact of the bloom’s going to be.

“It could change what species are occurring in the Gulf and what numbers they’re occurring in. It could have an impact on their recreational and commercial fishing activities in the Gulf.

“And if indeed, as seems almost certain, this whole bloom is as a consequence of climate change, then that’s extremely concerning for the future of us here and the planet in general.”

Since February, millions of fish and sea creatures across more than 200 species have died because of the phenomenon, which was described by not-for-profit OzFish SA as a “toxic blanket” smothering marine life.

Roanna Horbelt, the owner and operator of Kangaroo Island-based research and touring company RAD KI, said she had spoken to 30 or 40 people who had all “picked up dozens” of leafy sea dragons at the island.

Ms Horbelt said that before the algal bloom, she had only ever found one leafy sea dragon on the beach.

On Sunday, Ms Horbelt took photographs showing a mass of algae blobs covering the sea at Cape Cassini.

She said she observed the same shocking sight all the way up to Snelling Beach, about 37km away.

“We’ve actually been monitoring the water temperatures all year this year, and they’ve been an average of at least three degrees higher than any other year,” Ms Horbelt said.

“It’s like a bushfire in the oceans; it’s wiping out everything.

“It’s tough. It’s really, really bad.”

In a second community update on the crisis within a week, Kangaroo Island Council Mayor Michael Pengilly last week said local fishers were “being directly impacted and unable to operate in some areas” on the island.

While authorities had been forced to euthanise* 50 sick kangaroos at Tunkalilla on the Fleurieu Peninsula near the algae outbreak, an investigation has since found that toxic grass rather than algae had caused them to fall ill.

WATCH THE VIDEO

POLL

GLOSSARY

• algae: a simple, non-flowering aquatic plant
• unseasonably: in a way that is unusual for that time of the year
• renowned: famous or well known as an expert
• meteorology: the study of the atmosphere, especially weather
• microorganism: an organism that is so small you need a microscope to see it, such as fungus, algae and bacteria
• euthanise: to kill an animal in a humane way because it is ill, in great pain or dying

EXTRA READING
‘Barbie’ pink water could be algae
Woman trapped in mountain of ‘cornflake’ algae
Dolphins dance through glowing algal bloom

QUICK QUIZ
1. How big is the algal bloom?
2. How is it harming marine life?
3. What sea conditions have led to its growth?
4. What is the algae called?
5. What change in weather could break it up?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Bushfire in the ocean
This toxic blanket has been described like a “bushfire in the ocean”. Work with a partner and brainstorm some ideas that scientists could work on to help break this algae up or keep sea life safe from its toxicity.

List your ideas below;
–
–
–
–
Time: allow 10 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking

2. Extension
If global warming is responsible for the higher sea temperatures, what effect is this going to have on marine life going forward?

What should or could we be doing about this?

Time: allow 10 minutes to complete this activity
Curriculum Links: English, Science, Personal and Social, Critical and Creative Thinking

VCOP ACTIVITY
Punctuation thief
Pick a paragraph from the article, or about three sentences together if that’s easier, and rewrite it without the punctuation. At the bottom of the page write a list of all the punctuation you stole and in the order you stole it. For example; C , . C .

Then swap your book with another person and see if they can work out where the punctuation needs to be restored.

Make it easier: Underline where you stole the punctuation from but don’t put the list at the bottom in order.

Make it harder:

• Don’t put the punctuation in order at the bottom.
• Underline where you took the punctuation from, but don’t tell them what pieces you took.
• Just tell them how many pieces you took, but not what they are.
• Don’t give them any clues!