Dairy farmer Heather Campbell laughs as she invokes the term "carpageddon".
For the first time in her life, she's working amid the overpowering stench of rotten carp, with thousands of dead fish in more than 30 paddocks on her northern Victorian farm.
"I call it carpageddon because there's just carp everywhere. I've never seen so much carp in my life," she said.
"It's the weirdest thing. We've had mice plagues, locust plagues but we've never had a fish plague."
In Cohuna in northern Victoria, some farms are still draining floodwater.
"It's going to be a few years in some spots before damage is fixed," Ms Campbell said.
"We're only just starting to repair things."
The fish appeared just after Christmas when some dairy farms near Cohuna started irrigation.
Farmers were startled to see a lot of small carp swimming in the irrigation channel.
"I thought, that's a bit odd. Normally you don't see fish," Ms Campbell said.
Then she was shocked to smell thousands rotting in paddocks.
"We were watering and there were fish everywhere … and then suddenly there were thousands of fish everywhere."
"I can't even count, there are thousands of dead fish. It is completely feral."
Ms Campbell fears the dead fish could kill the cows, "because it's pasture — if we have one cow eat a dead fish, it might just keel over all of a sudden".
There are also fears the milk produced could be spoiled if cows drink poor quality water.
But if a cow eats a baby carp stuck in a paddock, it could be devastating.
"The cows are drinking that water," she said.
"Botulism is a major concern, with any dead animal near cow food. If it accidentally gets eaten, it could wipe out an entire herd."
Authorities say to find alternative water
Agriculture Victoria has urged farmers to exclude livestock from areas contaminated with decomposing fish, and if drinking water has similar contamination, then provide an alternative source of water for livestock.
It said dead fish should be removed before re-introducing livestock due to the potential to impact on animal health, or re-introduction of livestock delayed until the fish have fully decomposed.
But Ms Campbell said it was impossible to avoid using the paddocks impacted and impractical to remove all of the fish.
"This would mean picking up thousands of fish every day and leaving the cows with no feed."
She has asked the local vet if their cows can be vaccinated, to try and prevent botulism and any other illnesses that could be caused by eating carp.
"We don't really know what to do, because we've never had thousands of fish before."
Environment Department says 'it's common'
While the farmers have called on authorities to help clear the carp and improve the water quality, they fear little can be done.
"We're going to fence around outlets where there's a big concentration of dead fish, to try and minimise the chances of cows eating one," Ms Campbell said.
"There are only so many people to do all the jobs that need to be done. I don't know if it's going to stop and I don't really know what's going to happen."
Zeb Tonkin, a senior researcher with the Arthur Rylah Institute, said it was common for a large number of small carp to become stranded and die after flooding.
"What we're seeing isn't necessarily related to poor water quality, it's related to huge numbers of these young carp trying to come off the floodplain," he said.
He said the fish deaths are not a fish kill event and admitted infrastructure is supposed to keep carp off farms.
"We've got fish greens, that stops native fish being sucked into irrigation channels. Its also used to prevent carp getting into the channels.
"Its purely the sheer scale of this huge flood event, there's not much we can do in terms of management and infrastructure."
The Environment Protection Authority and North Central Catchment Management Authority were also contacted for comment.
