Dozens of swimmers are slashed by FISH at a popular lake in Sydney - as mother whose daughter was attacked says children could drown as a result

An eel-tailed catfish has been terrorising swimmers at a popular Sydney lake with children almost drowning as a result of their injuries.

Parents who visited Lake Parramatta in the city's west are begging the local council to re-zone the swimming area away from the dangerous fish. 

Jade Elizabeth Birks, 30, took to Facebook over the weekend to warn swimmers about the dangers in the water.

'FYI at Paramatta Lake there is an eel-tailed catfish biting everyone!' she wrote on Friday.

While the native fish looks harmless, during breeding season the males will do whatever they can to protect their nest.

Parents who frequent Lake Parramatta in Sydney's west are begging the local council to re-zone the swimming area so children aren't put at risk from the eel-tailed catfish

While the native fish look harmless, during breeding season the male fish will do whatever they can to protect their nest

As a result they pitch its fins and spines, rushing past victims at high speed and leaving a nasty gash.

Ms Birks said it can be quite traumatising for young children and watched up to 20 people who were bitten, with some so spooked they nearly drowned.

'One boy panicked so bad it looked like he was going to drown after it happened to him,' she said.

'He started panicking and people had to go and help him - he was that panicky he almost pretty much drowned.' 

'It leaves a nasty scratch or bite up your ankles because it latches on and rips your skin.' 

Parents are now urging council to move the swimming area as it is understood the eel-tailed catfish nest to the left of it. 

Parramatta District Parents on Facebook, otherwise known as ParraParents, said there are simple things to do to avoid being hurt.

Jade Elizabeth Birks, 30, took to Facebook over the weekend warning swimmers of the dangers in the water

Parents are now urging council to move the swimming area as it is understood the eel-tailed catfish nest to the left of it

'The good news is that there are some simple things you can do to avoid crossing paths with a protective Eel-Tailed Catfish and leave Lake Parramatta without any painful cuts and more importantly, a keenness to come back again and again like we do and to tell your friends how much fun it is to visit,' the page reads.

'The resident Eel-Tail Catfish nest in the left side of the swimming area amongst the pebbles so we recommend sticking to the right side.'

'It's also best to wear water shoes and keep your feet up near the surface - the Eel-Tail Catfish is a bottom swimmer.'

A Parramatta Council spokesperson told The Sydney Morning Herald that safety measures were being put in place during the catfish's breeding season.

Permanent signage and a 'lifeguard chalkboard' will be installed outlining current conditions in the water.   

Daily Mail Australia has contacted Parramatta Local Council for comment.   

THE EEL-TAILED CATFISH 

The eel-tailed catfish has a grey or brown body with black blotchings.

They build nests in areas of still water to breed and reproduction relies on temperature of the water.

Eel-tailed catfish are naturally distributed throughout the Murray-Darling Basin and in the Eastern drainages.

They usually are in lakes and sluggish turbid streams with fringing vegetation. 

Numbers have declines rapidly due to a range of impacts such as invasive species, habitat degradation, cold water pollution or fishing pressures. 

The fish reproduce in late spring to mid-summer with both parents protecting the eggs until after hatching.

Source: Department of Primary Industries