contamination issue in brisbane river

[benno573]

Bit of a concern for the river fishos... as in a big bit of a concern...

https://www.abc.net.au/news/2024-01-31/dead-fish-mud-crabs-wash-up-along-brisbane-river-after-rain/103408290

 

[AUS-BNE-FISHO]

I have seen lots of dead catfish and bony bream floating around Indooroopilly recently, its a shame that all these fish and crabs are dying. 

[mzaakir]

as much as i dont like fish dying, theres enough catfish in the brissy river @AUS-BNE-FISHO

[mangajack]

My bet is oxygen depleted water.

I was kayaking Caboolture River in 2011 when the weir breached upstream and a sudden gush of fresh water came down. All forms of life in the river started coming to the surface for oxygen...most did not find it and perished quickly....like 2 minutes and they were gone.   Hundreds of crabs, bream flathead, jew, jacks.....the fresh came down as a distinct line of fresh water weeds and 30 metres behind that was the dying critters.

I harvested a metre jew that morning by hand.

I didn't realise just how quickly it kills until that day.

I went up there for a last minute fish before the flush....did not get a bite, I got a shock.

[Hweebe]

1 hour ago, mangajack said:

My bet is oxygen depleted water.

Spot on all extra water would be carrying excess organic matter and microbes sucking all the oxygen out of the water. Normally the larger fish can outswim it but 1m jew would mean the inundation was rapid!

[mangajack]

3 hours ago, Hweebe said:

Spot on all extra water would be carrying excess organic matter and microbes sucking all the oxygen out of the water. Normally the larger fish can outswim it but 1m jew would mean the inundation was rapid!

That day the weed and fresh came down the river at probably 3 knots....it would soon overtake me in the kayak....probably match it's speed for a few hundred metres if i wanted to race it, but it would have won.

Odd sight to see freshwater weeds rolling down the creek like a log being rolled down the driveway. 20m behind that there was fish surfacing.

[Old Scaley]

I disagree with the West End residents saying there was nothing like this in previous floods. I often walk around the river side from West End to Kangaroo Point and last year there were masses of dead fish and some crabs belly up in the river. Having said that, IF there was a chemical spill it would be a worry. I hope the river gets back to being fish able soon but I think I will give it a miss for a week at least. 

[mangajack]

Mud Island will cop it this weekend because of all the rivers and creeks flushing in the past week.

Redcliffe has a lot of the pine flush influencing it too.