A row has erupted between anglers and migrant workers who are accused of catching fish and taking them home to eat rather than returning their catch.
The signs are in Polish, Lithuanian, Russian, Latvian and Portuguese
Local fishermen claim eastern Europeans are catching fish illegally in private lakes and rivers without a licence.
Many migrants see carp, perch and roach as part of their diet and struggle to understand the concept of fishing for pleasure without eating what you catch.
Signs in five different languages have now gone up at lakes in Southampton.
The signs, in Polish, Lithuanian, Russian, Latvian and Portuguese, have been put up at Little Testwood Lake and Nutsy Lake in Totton, which are reserved for members of Test Valley Angling Club.
The state that all fish must be returned to the water alive to ensure stocks are not depleted.
Andy Thomas, Environment Agency fishery officer, said problems have also been reported along the River Itchen.
He said: "We've received quite a number of reports from anglers fishing down here about certain fishing activity where coarse fish have been taken from the river.
"At the moment we don't have any real hard evidence that there's any environmental impact.
"For people from some countries the carp is a traditional dish so they've been quite quick to take them and unfortunately that has ruffled some feathers with our local anglers.
"From our viewpoint we have to make sure that all anglers fish legally and we want to make sure that's the case."
Anglers are not allowed to keep their catch at Little Testwood Lake
Barbara Storey is Polish and lives in Southampton, which has one of the biggest Polish populations in the country with more than 20,000 Poles living in the city.
Ms Storey, who is a translator and runs a helpline for Polish workers, said carp is traditionally eaten at Christmas in her home country.
"We fish for eating," she said.
"Most of the people believe that having some water and the opportunity to catch something like fish is mainly to have a good dinner when they go home.
"We believe it's quite cruel to hurt the fish, to cut the fish and then to put this poor little thing back to the water, dying there somewhere lonely.
"There is a culture difference that we have to sort out. We have to tell them [Poles] that local British people don't do it and they must know it."