Above - Photograph of the State Government algal bloom sign at North Brighton. (Media Credit: Madalyn Toet)

To swim or not to swim?

That is one of the many questions in South Aussies’ minds, especially in the lead-up to summer.

Context

The first signs of SA’s toxic algal bloom were recognised in early March this year, following reports of surfers’ falling ill, as well as brown foam and deceased sea life washing up on our state’s beaches.

The Government of South Australia describes algae as being a “natural part of our ecosystem” although some, like the Karenia species we are currently facing, have proved to be harmful to our environment.

“…This bloom is having a serious impact on marine life and the industries that rely on it – especially fishing, aquaculture and tourism,” said the Government of South Australia in their online media statement.

As a result of this widespread impact, the Government of South Australia has introduced a $28 million package to support research, communities, and industries in better understanding the toxic algal bloom.

What I’ve offered you here is a condensed version of events because, like all current events, they can be overwhelming. Over the past six months, we’ve been inundated with news on how to tackle the algal bloom and with this, the spread of misinformation has closely followed.

So here, this article sets out to debunk some of the myths that have been spread about SA’s toxic algal bloom.

MYTH 1: South Australian seafood is unsafe to eat

Whilst there are valid reasons for concern, seafood commercially sourced from South Australia is still safe to eat according to the Government of South Australia.

However, if you are catching any seafood that you plan to eat later, stick to these rules:

Above - Infographic detailing what SA seafood is safe to consume when privately caught. (Media Credit: Madalyn Toet).

MYTH 2: Algal bloom = no beach this summer

If the water is cloudy, stay away. If the water is clear, swim you may.

When visiting the beach, do your best to stay away from water that is discoloured or foamy.

If you do come into contact with this water and notice symptoms, rinse yourself with clean water as soon as you can.

Symptoms of irritation may include:

Skin irritation
Eye irritation
Coughing
Shortness of breath

MYTH 3: The bloom is causing a boom in shark attacks

South Australia’s Department of Primary Industries say that there is “no scientific evidence…to indicate that the algal bloom might make a shark attack more likely”, and this is supported by the research of Flinders University, South Australia.

However, professors and scientists at Flinders do say that increased shark observations may be linked to the toxic algal bloom along South Australia’s coast.

It’s important to note that this algal bloom is irritating our marine life, making it more difficult for them to breathe because:

1. Algal cells are damaging their gills (how they breathe).

2. Decomposing algae draws in oxygen, limiting what’s on offer to our sea life (aka oxygen).

With this stress, marine life has resorted to moving closer to shore in pursuit of cleaner and clearer water.

And what else is close to shore? Typically, swimmers and surfers.

So, this here – the stress the bloom has placed on marine life – may explain why sharks have moved closer to shore but remember there is no conclusive evidence to place the bloom as a cause for increased attacks.

MYTH 4: The bloom is caused by the ‘water getting warmer’

Yes, but it’s more than that.

According to the Government of South Australia, the algal bloom has been caused by three factors:

A marine heatwave (MHW) which has caused ocean temperatures to increase by 2.5 °C

The 2022/23 River Murray flood which is believed to have carried extra nutrients into the ocean - an ideal food source for algae. However, the time between the bloom and floods is making SA scientists question this as a likely cause as of recent.
A cold-water upwelling where wind has pushed away surface water, causing nutrient-rich water to resurface and replace it.

So, at a surface level the cause of the bloom being the ‘water getting warmer’ is somewhat true but to really understand the seriousness of the algal bloom, we need to understand its link to climate change.

I’m sure we’ve all heard the common misconception - a problem doesn’t exist if we’re not thinking about it. And unfortunately, this has been the approach many of us have taken to climate change.

We’ve used climate change as an umbrella term to describe the cause of extreme weather events: droughts, floods and the toxic algal bloom. And that’s fair because climate change is overwhelming and scary.

However, this approach has prevented us from being proactive and aware, particularly about the algal bloom. It’s taken the possibility of us not being able to enjoy the beach this summer for us to finally realise the seriousness of the bloom.

What now?

So, from here, I encourage you all to stay updated on the algal bloom and its development - all it takes is a quick Google search. It’s through understanding its causes and consequences that we can effectively tackle and prevent it from happening again.

Because we don’t want to be asking ourselves the same question - ‘to swim or not to swim’ - in twenty years time.

Debunking SA’s toxic algal bloom myths