Given the large number of dead fish washed up along the metro coast today, here's the latest comprehensive update. The little bit I contributed is in the appendix at the end!greatsouthernreef.com/2025-algal-bloom-june-update

Hi Ian. Is Spencer Gulf still good ?

So, there is no real cause of this bloom ?. Random natural event ?

The primary causes of the bloom are pretty well established: a nutrient-rich upwelling off the SE coast + warmer than usual sea surface temperatures + mostly light winds through summer and autumn. The microalgae are always around to some degree but these conditions were ideal to let some of the key species proliferate. Once they get to to a certain level, then all kinds of largely unpredictable things happen: other species can come into or leave the mix; levels of dissolved oxygen in the water can drop dramatically as the algae die off; and so on.

Spence Gulf seems OK still. The most recent storm pushed the bloom further up into Gulf St Vincent, including more on the eastern side, leading to the high numbers of dead fish found on the metro and mid-coast beaches over the last few days. There are no real signs that the bloom is dropping off any time soon.

I can't seem to find it, but I remember a some time back reading a science news article about ships transporting jellyfish in their ballast tanks, and these animals ending up and infesting unexpected locations. I was wondering if this could be a possible scenario for this algae ?

Looks like Moonta and the great lake are going to be my goto places for the time being. But I suppose Spencer will get infected eventually ?

BTW, thanks for keeping everybody informed Ian. I'm not on Whats App, but a mate has been txting me screenshots of your posts on that platform.

Not sure if this is another ABC beatup ?, but the protagonist is saying 18 months. Then she goes on to say this could be a interannual or regular event. This is turning into the COVID of the gulf

www.abc.net.au/news/2025-06-30/sa-algal-bloom-update/105476558

Not a beat-up in this case. Your analogy with covid is pretty apt in lots of ways...

Ok, that is really sad news. For me, it means limited sailing after work during summer (depending on how sick this sh~t it makes me). But I feel it for the seafood industry. These people are going to be out of work by the looks.

Regarding accidentally spreading this sh!t, what precautions do I need to take when cleaning gear ?. Is this sh!t hardy ?, or easy to kill ?. I was thinking if I sailed metro, then sailed Lake George or Porter lagoon. I've got separate boards and sails for ocean and lakes, but extensions and masts are shared. And then I have my harness etc. Zero all my boards ?