Yahoo TV

The dead fish, all seabream and white seabream, in the Richo Lagoon of the Drepano Lake in Igoumenitsa, appeared early on Tuesday (January 25) after temperatures in the lagoon had dropped as low as zero degrees celsius.

"They died from thermal shock," said local Ichthyologist Konstantinos Perdikaris from the Department of Fisheries, who visited the lagoon on Tuesday.

The Seabream species are sensitive to low temperatures and cannot survive below four degrees celsius, said Perdikaris. Usual temperatures in the lagoon at this time of year are about seven to eight degrees celsius, he said.

The fish were at a shallow depth where the cold was quicker to penetrate the water.

Drone video showed thousands of dead fish floating on the surface, in the water and on the shores of the lagoon.

The fish belonged to a local state-owned fish farm, and due to their containment in an enclosure in the lagoon they could not swim out to the deeper depths of the lake or sea to survive, said Perdikaris.

"Every year we free them into the lake, but this year unfortunately we did not have the chance to free them in time, because the frost (came quickly)," said fish farm cultivator Ioannis Ouzounoglou, who works at the farm, as he gathered the piles of dead fish from the lagoon onto a rowboat.

"In all the last years that I have been recording and measuring temperatures in the area, I never expected that we would have such low temperatures," he said.

The fish farm contained more than 600,000 fish of various species, and Ouzounoglou estimates that some 50 tonnes of fish were destroyed. Other species were not harmed.