Turkey has vowed action to fight the thick mass of marine mucilage, also dubbed "sea snot".
Boats are seen near the Caddebostan shore, on the Asian side of Istanbul, June 7, 2021.
President Recep Tayyip Erdoğan promised Saturday to rescue the Marmara Sea from an outbreak of "sea snot" that is alarming marine biologists and environmentalists.
Seagulls roost on rocks by the sea covered with a plague of 'sea snot', June 6, 2021.
In the Marmara Sea, these single-celled microorganisms also multiply by taking advantage of the marine pollution caused by domestic and factory wastes and the changing water temperature level due to global climate change.
A man steers a small boat out of sea snot in the port of Burgaz Island, June 5, 2021.
Istanbul residents enjoy their first Saturday without COVID-19 curfews in months and many took the opportunity to visit the city's Princes' Islands in the Sea of Marmara, which since May has been experiencing a phytoplankton boom known as sea snot or sea mucilage due to excess pollution in the marine ecosystem.