00:00Yes, so what we've got is tubing that sits on the sea floor and then compresses pump
00:08air at high pressure through holes in the tubing, effectively creating an underwater
00:14fence of bubbles that bubble up through the water to the surface and prevents things moving
00:20in and out of the bubble curtain.
00:24So we can see some pictures of a bubble curtain in action right now.
00:27Now when will this curtain be turned on?
00:32So the beauty of this technology is, now it's currently being put in place, you don't need
00:38to switch it on until you really have to.
00:40So the algal bloom is slowly working its way north up towards the cuttlefish.
00:45We don't know if it will reach the aggregation or not, but if it does, that's when it can
00:52be instantly switched on to protect a proportion of the egg population.
00:57OK, we're just seeing some pictures of the giant cuttlefish there as well.
01:02Tell us why these creatures need protection in this way.
01:07So it's a globally unique aggregation, which brings a lot of joy to people.
01:13They all go swimming and it's all shallow and it's just a magnificent sight.
01:17And two months a year they all come to this tiny area in the world, four to eight kilometres
01:23strip of coastline, really shallow water.
01:25And right now the adults have laid their eggs, they're dying off naturally now, that's part
01:33of their natural life cycle.
01:34And all you've got left are eggs, hundreds of thousands and tens of thousands of eggs
01:39underneath these rock ledges, big large eggs.
01:42And they're the next generation.
01:44So mum and dad aren't around anymore if something happens to these eggs.
01:49So by protecting these eggs, we have a good chance of, if the bloom does get there and
01:55does its worst, of help protecting the next generation of cuttlefish.
01:59Right, because the algae could presumably kill the eggs.
02:03This curtain only covers a small area.
02:06Will that be enough?
02:07If the algal bloom does make its way to this breeding ground, to where the eggs are, will
02:11the curtain be enough to protect the eggs and ensure that some cuttlefish survive?
02:16Well, there are lots of unknowns, so this is a trial.
02:20But we've done some calculations in terms of the proportion of eggs that should survive
02:25to adulthood.
02:27And we believe by coordinating off, it's about 10% of the egg population that's there, cephalopods
02:33have, which are the cuttlefish, octopus, squid animals, that they have a short lifespan so
02:38they can reproduce quickly and bounce back quickly as well.
02:42And News Breakfast was in Wyala looking at cuttlefish populations just a couple of weeks ago.
02:51Can you tell us though, how are they doing at the moment?
02:53Because they are a threatened species and they do have this unusual life cycle where they
02:56breed and then die and then fingers crossed that the next generation thrives.
03:00So, I've heard people that have been in the water regularly that the population is healthy,
03:07it's thriving, the water is clean and to indicate there's no bloom at the moment.
03:12So, there was an active breeding aggregation there, there was tourists visiting the region
03:17watching the cuttlefish and there's a healthy batch of eggs there.
03:21And they take about three to five months to develop.
03:24So, they're in the water for quite a while before they hatch and this curtain really helps
03:29buy us time.
03:31And just lastly Zoe, before we let you go, let's presume the curtain works, the next generation
03:37of hatchlings come out, it all looks good.
03:39What are their chances once they leave that area and they have to endure the algal bloom,
03:44which is of course moving around a lot of the state's coastline in pretty unpredictable
03:48ways?
03:49So, once they hatch, the hatchlings kind of disappear, they're quite cryptic.
03:53We don't know exactly where they go, but they likely stick all in the upper Spencer Gulf region.
04:00So, once they disperse, we hope that the algal bloom is a bit patchy and dynamic.
04:08So, we hope that there's some hatchlings that can survive in some nooks and crannies where
04:12the bloom doesn't go.
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