Locals in South Australia have been left stunned by the sight of thousands of dead fish that have washed ashore at a popular beach.

Footage obtained by 9News appears to show thousands of dead carp blanketing Middleton Beach on the Fleurieu Peninsula.

Onlookers say the smell is “horrendous” and the odour wafting from the carcasses can be smelt “from streets back”.

Though confronting, experts agree that mass kill events can happen due to changes in number of natural factors. (Instagram)

Though confronting, experts agree that mass kill events can happen due to changes in a number of natural factors.

These factors include salinity and oxygen levels in the ocean and the temperature of the water.

Diseases and pollutants can also contribute to the deaths. (Instagram)

Diseases and pollutants can also contribute to the deaths.

Just weeks ago, a similar event occurred at the same beach.

It’s not currently known what the exact cause of the deaths is or if recent flooding in the area was a factor.

The Department of Primary Industries and Regions SA has been contacted for comment.

It is not believed the dead fish pose any danger to swimmers, though it’s not advised to handle the carcasses. 

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