EPA data: at least four million salmon died prematurely at Tasmanian farms in 2025

At least four million Atlantic salmon died prematurely at Tasmanian fish farms in 2025, new data from the state’s Environmental Protection Authority shows. The EPA’s figures suggest about 500,000 fish died in November and December as ocean temperatures warmed. More than 2,500 tonnes of salmon died in the last three months of 2025, bringing the annual death toll to 20,133 tonnes lost before being processed for public consumption, according to EPA data published on Friday afternoon.

More than 40 tonnes of salmon died per day in December, almost triple the monthly average for July to October. Scientific studies cited in the data note that Atlantic salmon are adversely affected when ocean temperatures approach 18C; at higher temperatures they encounter less oxygenated water, suffer liver and kidney damage, have less appetite and become more vulnerable to disease.

Stewart Frusher, a retired professor from the Institute for Marine and Antarctic Studies, said the December increase was "an ominous sign" and that "the waters in south-eastern Tasmania aren’t fit for purpose for salmon." Tasmania’s Animal Welfare Act requires owners not to use management methods likely to cause unreasonable and unjustifiable pain or suffering.

There have been calls for companies to face substantial fines for mass fish deaths.

Key Topics

World, Atlantic Salmon, Tasmanian Fish Farms, Environmental Protection Authority, Animal Welfare Act, Stewart Frusher