Fish kill Clarence river

[alleycat]

I feel very deeply for the poor people who suffered the floods as a person who as a child saw my house go right under in 74, but as a fisherman who targets flathead i find this really tragic, so many dead fish in such a small area, my grandfather farmed on the macleay river all his life always said it was water that came off smart weed that killed the fish, either way this is not nice to see and will take years to repair, this is where govt should have spawning projects and hatcheries..
Fishing Australia TV - Post flood fish kill on the Clarence River | Facebook
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[gunna]

Yep. Just awful.

[NAGG]

Very sad to see - unfortunately I don't think it will be the last with all that flooding - a hell of a lot of chemicals , pesticides & other pollutants end up in the waterways during these events. .

Chris

[Kev_McC]

That’s true, although the nasty things are usually quite diluted by the huge volume of water. They typically need to be at a certain concentration to cause harm, so in flood events it’s most often a lack of dissolved oxygen that causes fish kills. This is usually soil erosion at a vast scale that drives this, all of the organic material that is part of the surface layers of soil. Huge loads of this organic matter start to decompose in the hours and days following the flood and the microbes quickly burn through the oxygen in the water. Bigger fish seem to get rolled first.
Fish kills from chemicals usually result from storm events that cause sudden heavy runoff from a smaller area, say a town or some cropping land. Results in a ‘slug’ of water with more concentrated pesticides and other chemicals moving through a system.

[chris69]

You would think that the fish would have moved out to sea there’s a lot of flathead in the pic and a good perch or bass with all the farms around there something had to kill them.

I would think NSW fisheries would do a test on them to find out.