Třeboň fish farmers begin emergency fish rescue as unprecedented drought grips the region

In the fish ponds of Třeboň in southern Bohemia, an unprecedented drought has forced fish farmers to carry out unplanned emergency catches, as fish face death from lack of water and oxygen. According to Vladimír Kukačka, director of the local fish farming company, even the oldest residents don't recall a drought like this — the last time conditions came close was after World War II.

Fish farmers, who regularly measure water volumes in the ponds, report a shortfall of 28 million cubic meters — comparable to an entire small reservoir. Every week, the Třeboň ponds lose to evaporation a volume of water equal to that of Opatovický Pond, which covers 165 hectares.

Trouble ahead for the autumn catch

The company has yet to calculate the economic damage caused by the drought. But it's already clear that the water shortage will complicate the planned autumn fish harvest — there simply won't be anywhere to keep the fish in holding tanks. Normally, water for these tanks comes from ponds located higher up, which are then fished in spring. Right now, however, water levels there are one to one and a half meters below normal, leaving nothing to fill the tanks with.

Saving the fry, wary of netting the larger ponds

A similar situation is unfolding at the fish farm in Hluboká nad Vltavou. Several small ponds — Blatec, Hlasenec, and Dolní Novosedský — where fry were being raised, have already been emptied out. The fish have been moved to areas with more water, said the farm's director, Vladimír Kaiser.

Fish farmers are trying to aerate the water to keep the fish from suffocating, but the method doesn't work everywhere. "It all depends on the depth of the water column. Where there's too little water, you can't aerate it properly — you'll just stir up mud from the bottom, and it won't do any good," Kaiser explained.

The farm had also considered netting the larger ponds, but fears this could turn into a disaster for the fish. With the current heat and shrinking space, the fish could die before anyone even manages to catch them, Kaiser warned.

Source: novinky.cz