On Saturday, dead fish began appearing again on Turan Beach in Izmir Bay, located along Türkiye’s western coast, a site that drew attention last year due to foul odors and fish deaths. Today, large numbers of dead fish were observed washing up along Karşıyaka’s shoreline.
Teams from the Izmir Metropolitan Municipality collected the fish and disposed of them in garbage bags. The bay’s water has turned green and brown and the coastline has remained deserted due to the strong odor.
Bülent Onur, walking along the beach, told Anadolu Agency (AA) that the smell had persisted for two days. "Last year, there were also odors and fish deaths. This year, it has started for the first time. The smell has decreased but remains unpleasant,” he said.
Gökhan Havuz, visiting Karşıyaka from Afyonkarahisar, added, "There are dead fish everywhere, from large to small. The smell is extremely strong. We come here often, but this is the first time we’ve seen this.”
Professor Ergün Taşkın, head of the Department of Hydrobiology at Manisa Celal Bayar University, explained that Izmir Bay faces significant pressure from urban, domestic, industrial, port and agricultural activities. He noted that the bay ranks among Türkiye’s lowest in water quality.
"There is a high input of nutrients and alluvium,” Taşkın said. "At the end of summer, opportunistic and toxic algal species increase due to pollution and rising water temperatures. Toxic phytoplankton either produce ichthyotoxins or clog the gills of fish, causing mass deaths. Unless pollution is fully controlled, these events may recur annually.”
Taşkın emphasized that all streams and canal waters entering the bay must be monitored and no pollution load should be allowed. He also recommended removing accumulated sediment from the inner bay and properly disposing of it on land.
Recently, environmental experts have warned that pollution in Izmir Bay is causing recurring ecological problems and persistent foul odors. Dr. Levent Yurga, a faculty member at Ege University’s Faculty of Fisheries, said, "The proliferation of bacteria that decompose dead plankton and marine animals is the main source of the persistent odor, which worsens as rising temperatures accelerate the breakdown of organic matter.”
He added: "The proliferation of cyanobacteria, diatoms and dinoflagellates has caused mass fish deaths. Even cartilaginous fish, typically the most resilient species, were affected at the beginning of 2025.” While no large-scale deaths have been recorded this year, the odor has resurfaced due to environmental pressures and nutrient overload.
Tracing the problem back to the 1990s, Yurga said, "Unchecked industrialization and direct discharge of domestic and industrial wastewater began degrading Izmir Bay. Early mitigation attempts, such as covering streambeds with concrete, failed to address the root causes.” He also praised later efforts, noting, "The Great Canal Project and the removal of Ragıp Paşa Lagoon allowed the bay to self-clean and biodiversity to gradually recover.”
However, he warned: "Rising pollution and overfishing have once again disrupted the bay’s natural balance. Phytoplankton overgrowth reduces oxygen levels and threatens marine life.” Yurga emphasized that short-term fixes are insufficient, stating: "Removing sea lettuce or using chemicals is both ineffective and harmful. The only long-term solution is to halt pollution at its source, particularly from rivers carrying industrial waste.”
Last year, on Aug. 20, dead fish washed ashore at Turan in the Bayraklı district, prompting authorities to investigate the sources of pollution and take measures to prevent further damage.