Does anyone know what might cause the death of these fish? (oder river germany/poland)

[Sgooosh]

'Gigantic' ecological catastrophe in Europe as 10 tons of fish wash up dead

"We are dealing with a gigantic and outrageous ecological catastrophe," the former head of Polish Waters said.

www.nbcnews.com

Here's a news article that i find interesting. there are many dead pictures of shellfish and fish, and they do not look normal. what do you think caused them to die?

it almost looks like an ammonia poisoning, or bacterial infection on the skin
but those dead fish might be old and something ate the skin

 

[itiwhetu]

Nitrate poisoning, farmers are using way too much fertilizer and the runoff gets into the water ways, causing high nitrate levels.

 

[itiwhetu]

I would have lost my Discus to this problem if I hadn't got my act together. It was a big wakeup call for me about tank maintenance

 

[Deleted member 149562]

European rivers have been running dry due to excessively high temperatures this summer. Several rivers have even dried up completely.

Since cities along those rivers, along with other industries frequently dump waste products into the rivers routinely and usually safely, the lack of water level has caused the toxins to increase significantly thus fish and other wildlife has died.

Die-off like this happens anyway but not in such vast numbers normally

The basic reason is simply that the toxic levels of stuff pumped into the river is far more concentrated than normal...not due to more toxins being put into the rivers but due to the lack of water and flow within the rivers themselves thanks to the massive heatwaves

Once the rains get going properly in the autumn and winter months, the rivers will be back to their normal levels and the water will, along with the increased flow rate of the rivers, handle the toxicity perfectly fine.

There is also a major issue of increased algae, including blue green, in rivers, canals and lakes where water levels have dropped due to the weather and what water is left is becoming stagnant in the hot weather.

Warning to pet owners after dog 'dies of toxic algae poisoning'

Haddo Country Park and Fyvie Castle joined SEPA in warning pet owners to keep their dogs out of lochs and ponds.

news.stv.tv

 

[Naughts]

Drought + heat + concentrated pollution = low oxygen.

We are seeing similar mass die offs in the UK that it is due to drought.

 

[itiwhetu]

Drought + heat + concentrated pollution = low oxygen.

We are seeing similar mass die offs in the UK that it is due to drought.

=nitrate

 

[Essjay]

There was also a mass die off of crabs and other crustaceans along the north east coast of England a few months ago, there were huge numbers washed up on beaches. Initial findings blamed algal blooms, though that is not universally accepted.

Update on investigation into the deaths of crabs and lobster in the North East

Results of investigation point to a naturally occurring harmful algal bloom being the cause.

www.gov.uk

 

[Colin_T]

Get use to it people, climate change is here and it's going to happen more and more often and will continue to happen even after the CO2 levels stop increasing.

 

[DoubleDutch]

Get use to it people, climate change is here and it's going to happen more and more often and will continue to happen even after the CO2 levels stop increasing.

Only thing is there is not any sign that climate change caused this. It is the 13th river of Europe so it isn't a closed system or what so ever.

Poisoning is the most plausible but they still don't have any clue with what. Quite strange to me.

 

[Colin_T]

Poisoning, and warm water causing low oxygen levels. When fish die they release ammonia, which adds to whatever caused the problem and poisons more things. Big chain reaction and everything dies. Just like humans and everything else on this planet in the next 30 years.

 

[Deleted member 149562]

There is alot of heavy industry based all along the Oder....including the huge oil refinery at Schwedt. This refinery handles most of the aviation fuels and vehicle fuels needed across Germany and Poland (it is supplied by overland pipeline from Russian territory, it is still pumping despite current sanctions).

There is also a huge ruin, that of IG Farben's Politz Synthetic Oil Plant along with at least 6 concentration camps. These were built by the Germans in the 1930's and used extensively throughout the second world war until the plant was almost completely destroyed by Allied bombing and Soviet liberation in early 1945. The ruined plant is open to tours but much of it is still closed off due to significant pollution and toxic waste products that need to be dealt with, much of this has soaked into the soil and into the water table.

The Oder area was one of the highest priority targets in WW2 due to the heavy industrial areas along its banks...it also featured in the dam busting attacks. There is a tremendous amount of "historical" pollution in the soil which becomes significantly harder to control in drier weather where those pollutants simply are not diluted enough by rainfall and the rivers to be harmless to wildlife.

So in regard to unusually high levels of pollution in the Oder, it really is not too surprising with the lack of rainfall, lower river water levels, lower river flow rates causing a more concentrated level of toxicity. The controls in place against pollutants getting into the water table and rivers for industry post war is substantially better than those concerned with pollutants held the soil and derelict ruins from WW2 where much of what was built during that time and subsequently destroyed or abandoned is still being discovered. Compared to nowadays where we know what is toxic and what should not be used, back in the run up to WW2 and during that war there were no such rules or knowledge and the bulk of what was used we now know was often extremely toxic and very difficult to remove or control any seepage.