Tourism in Marmara Sea under mucilage threat

Created by microalgae that reproduce excessively, the mucilage in the Marmara Sea has devastated the fishing industry, and now threatens the tourism sector, experts warned. Although the phenomenon is naturally occurring, human activity has manipulated nature to create an excessive incident, they said.

Aynur Tekin / DUVAR

Caused by the over-reproduction of certain types of microalgae, the mucilage in the Marmara Sea has severely hurt the fishing industry, and stands to damage local tourism, experts have warned.

Bandırma 17 Eylül University's Naval Faculty Dean Prof. Mustafa Sarı noted that the current case of mucilage is more severe in quantity and density than the previous incidents in 1992 and 2008. 

An increase in the sea water temperature has worsened the phenomenon, Prof. Sarı said, adding that the Marmara Sea is 2.5 degrees above seasonal averages.

Prof. Mustafa Sarı

"Secondly, the water is saturated with nitrogen and phosphorus, which feed the algae," the expert noted on the cause behind the intense mucilage. "Third, the sea is calm. There's little vertical circulation and a relatively small amount of horizontal currents."

Prof. Sarı said that one of these three factors needs to be altered in order to reduce the amount of mucilage, noting that the water temperature and water currents weren't possible to alter fast enough. 

"There's only one factor we can alter, which is to decrease the amount of nitrogen and phosphorus in the sea," the expert said.

'Mucilage is natural occurrence but humans pollute nature'

Mucilage is a natural phenomenon, but humans manipulate nature through pollution, the head of the Union of Chambers of Turkish Engineers and Architects Chambers (TMMOB), Ahmet Kahraman, said. 

"We interfere with nature through water pollutants and climate change," Kahraman noted.

Microalgae that create mucilage can only reproduce if they can find nutrition, which is provided by the pollutants humans put in the sea, the expert said. 

"The pollutants we release into the water satisfy their need for nutrition, and the habitat is completely yielding to their life," Kahraman said. 

Mucilage eventually sinks to the bottom, Prof. Sarı added, noting that this causes the death of not just fish, but other sea creatures as well.

"The stuff on the surface is mucilage that's done breaking up. The stuff at the bottom is the real threat," Prof. Sarı said. "Divers can barely see each other under the water near Istanbul's Prince's Islands."

'Tourism industry is worried'

The fishing industry has devastated fishers in the Marmara Sea, Prof. Sarı said, noting that hundreds of fishing nets went missing in the water as a result of mucilage. 

"People are not looking at the water on the beach and wondering if they will be able to swim at all this summer. Mucilage is about to strike tourism. The coming years will not see tourism as we know it unless we fix the mucilage," the expert said. 

Cleaning up the mucilage will only be possible with extensive wastewater purification systems, Prof. Sarı said, adding that the government should take the lead on the efforts.