In Switzerland's Bernese countryside, where persistent droughts are devastating the aquatic ecosystem, rescuers have saved tens of thousands of fish from drying sections of the River Emme, but falling waters are now putting the effort in jeopardy.

This summer's scorching heatwave and drought have pushed some of its major rivers to exceptionally low levels, and the River Emme is no exception. The riverbed of River Emme is now bare and dry enough to walk across.

"See that bird in the tree? The annoying bird? That's the one that ate the last fish," said a local man along the river.

Over the past few weeks, local fisheries authorities and volunteers have been carrying out emergency rescue operations. Their mission is to rush to sites where fish are perishing in large numbers or where sections of the river are about to dry up completely and move the fish to safer waters.

The method involves using hand-held nets that emit a mild electric current to stun and scoop up the fish, which are then relocated to stretches of the same water system that are deeper and richer in oxygen. But as the entire catchment continues to lose water, such safe havens are becoming harder to find.

By mid-August, over 90,000 fish had been relocated across the canton of Bern. However, most of the viable receiving waters are now already occupied. Worse still, the water level is falling faster than the rescue teams can keep up.

And the River Emme is far from the only waterway suffering from extreme drought. The fisheries department warns that persistently high temperatures, prolonged low flows, and increasingly frequent extreme weather events are collectively taking a heavy toll on the region's aquatic ecosystems.