Plagued Waters: The Marmara Sea and the Fight Against Mucilage

Marmara Sea, Turkey — Covering more than 70% of our planet, the world’s oceans and seas produce between 50–80% of the oxygen we breathe, store up to half of the Earth’s carbon, and provide a home to 80% of all life on Earth. But in Turkey, the health of these waters is under direct threat.

Studies show that 90% of marine litter in Turkey comes from land-based sources: plastics, chemicals, metals, rubber, paper, textiles, abandoned fishing gear, and even derelict vessels. When this waste enters the sea, it doesn’t just pollute—it fuels one of the Marmara’s most alarming crises: marine mucilage.

Photo: Getty Images

What is Marine Mucilage?

Commonly known as “sea snot” or “sea saliva,” marine mucilage forms when algae are overloaded with nutrients. Pollution combines with rising sea temperatures, allowing the algae to bloom excessively. The Marmara’s first major outbreak was recorded in 2007. Since then, mucilage has devastated marine biodiversity, wiping out over 60% of species. At least 19 species have disappeared from the region, while 22 more—including bluefish, tuna, turbot, and swordfish—are considered commercially extinct.

The consequences are visible at every level:

• The mucilage blanket blocks photosynthesis, starving the sea of oxygen.

• It smothers the seabed, killing mussels, corals, and benthic life.

• It produces a foul odor, reducing tourism and damaging the livelihoods of coastal families.

  
  

The 22-Point Action Plan

In June 2021, Turkish officials launched a 22-Point Action Plan to fight mucilage. More than 1,197 cubic meters (42,271 cubic feet) of mucilage were cleaned from the sea using 43 boats and vessels. Researchers at Istanbul University also tested marine bacteria as a natural method to reduce the slime’s growth.

Murat Kurum, head of the Ministry of Environment, Urbanization, and Climate Change, announced further measures:

• Increasing wastewater treatment capacity, with a target of 15% reuse by 2030.

• Expanding monitoring stations from 91 to 150, with 24/7 supervision using satellite, drones, radar, and early-warning systems.

• Developing a digital twin of the Marmara Sea, a 3D model integrating data on pollution, meteorology, and ecosystem health for real-time monitoring.

Since 2016, the project has accelerated, with 423 monitoring stations, 11 institutes, and 3 research vessels working in three-year cycles. The MARMOD initiative has modeled possible futures for the Marmara—ranging from ecological recovery to further decline—depending on action taken.

Photo: The Marmara Project

Why Action Matters

Large-scale interventions are vital, but officials admit they cannot solve the problem alone. Pollution starts on land, which means individual actions matter just as much as institutional ones.

• Dispose of waste properly and reduce plastic use.

• Participate in clean-ups and community projects.

• Support petitions and NGOs working to hold industries accountable.

The Marmara Sea is more than a local body of water—it’s a vital ecological gateway between two continents. Saving it will require cooperation between scientists, policymakers, and everyday people.