Blue Waves = Red algae

blindboy's picture
blindboy started the topic in Monday, 25 Aug 2014 at 10:05am

The blue glow is produced by red algae.

blindboy's picture
blindboy's picture
blindboy Monday, 25 Aug 2014 at 10:08am

Red algae are potentially harmful and lifeguards generally close the beach if there are visible blooms. So very pretty but an indicator of poor water quality. There were a few reports yesterday of red algae on the tide lines so a little caution might be advisable before jumping in on the northern beaches this morning.

stunet's picture
stunet's picture
stunet Monday, 25 Aug 2014 at 10:17am

Yesterday there was an outbreak of pink algae at Thirroul. Not just a shade of pink either, it was deep pink similar to the lake on the way into Cactus (if you've ever seen that). When it came through the lineup the water looked as if someone had dumped a load of pink paint. The particles were extremely fine, not like the red algae often seen up the north coast, but more cloudy.

Probably would've looked great once the sun went down.

stunet's picture
stunet's picture
stunet Monday, 25 Aug 2014 at 10:19am

You sure it's an indicator of bad water BB? I see red algae often up at Forster/Pacific Palms where the water quality is great. I always assumed it somehow was linked to fresh water - run off from rainwater or lakes.

blindboy's picture
blindboy's picture
blindboy Monday, 25 Aug 2014 at 11:32am

I am sure Stu. They are linked to nutrient load so would be quite likely in the Forster/Pacific Palms area as the lakes would carry run off from septic tanks and fertiliser. As an aside the water quality around Forster itself can be very poor unless they have recently upgraded their treatment works. Red algae do not necessarily indicate the presence of pathogens but as they can produce toxins themselves they are worth avoiding. The blooms have been increasing steadily over the years related to greater nutrient load from increased population and possibly warming from climate change.

freeride76's picture
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freeride76 Monday, 25 Aug 2014 at 12:28pm

Not quite a definite correlation between the common red algal blooms inshore and nutrient load.
http://www.water.nsw.gov.au/Water-Management/Water-quality/Algal-informa...

They usually appear here on the North Coast with the first strong surges of the EAC in December.

the_b's picture
the_b's picture
the_b Monday, 25 Aug 2014 at 12:36pm

Often see the north coast red algae blooms after a noreaster and/or EAC currents causing an upwelling. Nutrient rich deep waters come to the surface.

Was out off longy in the tinny on Sunday and saw areas with what looked like coral spawn.

blindboy's picture
blindboy's picture
blindboy Monday, 25 Aug 2014 at 1:38pm

Point taken freeride but it is still nutrient load just from upwelling rather than run off. In Sydney the sewer outfalls are in deep water. I am not sure if they could be involved in the upwellings or not but will do some research.

Craig's picture
Craig's picture
Craig Monday, 25 Aug 2014 at 1:52pm

Yeah BB is on the money.

You get it a lot around the Forster area due to the EAC breaking away from the coast around Sea Rocks resulting in eddy formation and deep water upwelling. Similar occurs at other breakaway points/upwelling regions further up the North Coast.

But you also get it from excess nutrient loads being flushed into the ocean, ie fertilisers etc.

Main problem with the algae is that it they produce neurotoxins as well as depleting the water column of oxygen, making it anoxic.

blindboy's picture
blindboy's picture
blindboy Monday, 25 Aug 2014 at 4:24pm

Craig, not sure that these ones produce neurotoxins. They are probably Noctiluca which cause problems by excreting ammonia.

Craig's picture
Craig's picture
Craig Monday, 25 Aug 2014 at 4:27pm

Ah cool, not totally across what they produce but know they suck up the oxygen and also put a blanket over the ocean, hence stopping any more oxygen mixing in from the atmosphere.

Craig's picture
Craig's picture
Craig Tuesday, 26 Aug 2014 at 11:20am

Got some shots last night of the bioluminescence, never seen anything so amazing! Never knew it was that bright and vivid, like glowsticks bouncing in the surf!



zenagain's picture
zenagain's picture
zenagain Wednesday, 20 May 2020 at 11:08am

I'm guessing some of these were filmed on GlowPro TBB?

AlfredWallace's picture
AlfredWallace's picture
AlfredWallace Wednesday, 20 May 2020 at 12:05pm

FYI. Inland Pink lakes away from the coast are generally made up of halophilic (high-hyper saline) fine green micro algae mostly of the type Dunaliella salina. The pink colour is the result of the production of carotene. Carotenoids make their way in the food chain and are a readily consumed by shrimps/prawns hence the colour.