An increase in the amount of a slime-like substance in the water threatens corals and the fishing industry. When viewed from above, it looks like a beige mass spreading out over the dark blue waters of the Sea of Marmara. Up close, it resembles a creamy, gelatinous blanket of quicksand. Scientists warn that levels of this substance, known as “sea snot,” are rising as a result of global warming.
Until 2007, no cases of this slimy substance had been reported in Turkish waters. It forms as a result of prolonged warm temperatures and windless weather, as well as in areas with large amounts of nutrients in the water.
Phytoplankton, responsible for growth, get out of control when seawater is high in nutrients such as nitrogen and phosphorus. These nutrients have long been abundant in the Sea of Marmara, which receives sewage from nearly 20 million people and is fed directly from the nutrient-rich Black Sea.
In normal amounts, these tiny, floating sea plants are responsible for oxygenating the oceans, but their overpopulation creates the opposite effect. When oxygen is scarce, they secrete a slime-like substance that, under favorable conditions, can cover many square kilometers of the sea.
In most cases, the substance itself is not harmful. “What we see is basically a combination of proteins, carbohydrates and fats,” says Dr. Neslikhan Özdelice, a marine biologist at Istanbul University. But the sticky stuff attracts viruses and bacteria, including E. coli, and can become a blanket that suffocates marine life below.”