100-Plus Tons of Dead Fish, and Their Smell, Swamp a Greek Port City

Authorities in central Greece said on Thursday that they had dredged more than 100 tons of dead fish from the waters around the port of Volos, a scenic summer destination, after a mass die-off of fish that is believed to be linked to climate change.

As televised images on Thursday showed fishing boats trawling through a silvery blanket of dead fish that formed off the port earlier this week, passers-by snapped photographs of the gruesome scene on their cellphones.

Greek officials traded accusations over the disaster as seafront businesses dependent on tourism said they have seen their revenues slashed by 80 percent since the freshwater fish showed up earlier this week.

And then there was the horrific smell that wafted through the port and its surrounding area.

Scientists said the deaths most likely resulted from a combination of global warming and inadequate water management.

Southern Europe has been grappling with the adverse effects of higher temperatures enveloping the region. This summer’s extreme heat has stoked more frequent wildfires, heat-related deaths and flooding — along with the growing threat of drought.

The fish are believed to have been forced downstream to Volos from the area of Lake Karla, a European Union-protected wetland, which saw its water levels rise sharply after a major storm that caused widespread flooding in central Greece last fall.

The storm had flooded some 50,000 acres of land around Lake Karla, said Pantelis Sidiropoulos, an assistant professor of rural and surveying engineering at Aristotle University in Thessaloniki.

But extreme temperatures caused much of that water to evaporate, leaving masses of fish in dwindling waters with inadequate oxygen and poisoned by toxins, Mr. Sidiropoulos said in a telephone interview.

“The fish are basically victims of climate change,” he said, noting that his colleagues had seen dead fish in the farmland next to Lake Karla earlier this week.

“The authorities had months to remove the fish from the area,” he added. “They’ve been sitting in stagnant waters for a long time.”

Local authorities did not respond to a request for comment.

Greece’s Supreme Court prosecutor, Georgia Adeilini, on Thursday ordered an investigation into the die-off, referring to “a nightmarish image of tons of dead fish in Lake Karla and the Pagasetic Gulf.”

She said the investigation would determine to what extent the authorities should be held accountable for failing to prevent Lake Karla’s waters from seeping into the sea.

Achilleas Beos, the mayor of Volos, said he had warned of the potential effect of flooding of agricultural plains adjacent to Lake Karla after last year’s storm. He described the disaster as an “environmental crime.”

Dimitrios Iakovakis, who owns one of the largest fish tavernas on the Volos seafront, said he had lost most of his customers over the past few days.

“It’s deserted,” he said of his restaurant, noting that his revenues had plunged to 200 euros a day, or $210, from 5,000 euros, about $5,500.

“The smell is unbearable,” he added, noting that in his 25 years of running the taverna, he had never seen anything like it. “A sea of rotting fish five meters from our tables. Who could have imagined it?”