By Dilara Senkaya and Ali Kucukgocmen

ISTANBUL (Reuters) – Turkey vowed to save the Sea of Marmara on Tuesday by launching a disaster management program meant to clean up a slimy “sea snot” outbreak threatening marine life and the fishing industry.

The thick layer of organic matter, known as marine mucilage, has spread through the sea south of Istanbul covering harbors, shorelines and swathes of the surface. Some has sunk below the waves, suffocating seabed life.

Environment Minister Murat Kurum said 25 sea surface-cleaning and barrier-laying boats, as well as 18 other vessels, were working to prevent the spread of the mucilage. Illegal fishing and “ghost” nets would be halted and Turkey would declare Marmara a protected area by the end of 2021, he said.

“We are starting our cleaning efforts both on land and at sea at 15 points today,” Kurum said. “We are determined to save the Marmara and we will save it.”

Some 1,000 workers would bring the waste to shore and truck it to municipal facilities, he said.

Scientists say climate change and pollution have contributed to the proliferation of the substance, which contains a wide variety of microorganisms and can flourish when nutrient-rich sewage flows into seawater.

Residents welcomed the clean-up, but complained about what they called years of uncontrolled pollution in the sea.

“Of course, this sea snot is something that is caused over a few years. Formed by our years-long unawareness, the harmful substances thrown into the sea caused a vomiting in the seabed and when there was no current, it stayed there,” said Kadir Saydam, a 65-year old pharmacist.

“Having the cleaning efforts is good visually,” he added.

President Tayyip Erdogan has blamed the plague on untreated water from cities including Istanbul, home to some 16 million people, and vowed to “clear our seas from the mucilage scourge”.

(Writing by Tuvan Gumrukcu; Editing by Jonathan Spicer)