Rare marine life spotted again off Istanbul’s Princes’ Islands

ISTANBUL

Divers exploring the Princes’ Islands off Istanbul encountered rare species including tope sharks and angular roughsharks, revealing a thriving underwater ecosystem in the Marmara Sea despite environmental pressures.

Dives at Viranbağlar, Yelkenkaya, Kurşun Burnu, Sivri Ada, Kalpazankaya, Hastane Altı, Terk-i Dünya and At Mezarlığı captured returning species. While exploring At Mezarlığı, south of Büyükada facing Sedef Island, divers found large horse bones mingling with active marine life, dive instructor Mehmet Karail said.

Divers spotted a 60-centimeter tope shark and three John Dorys during a single night dive, welcoming the chance to observe species rarely seen in recent years, Karail said. He said they observe lobsters and octopuses frequently.

The region hosts extensive biodiversity. Cameras recorded starfish, swimming crabs, pipefish, sea hares, blennies, scorpionfish, gobies, hermit crabs, tub gurnards, red-lipped gobies, peacock’s tails, warty crabs, combers, crabs, sea pens, anemones, rocklings, stingrays, corals, squids, wrasses, pen shells, flounders, weevers, sea cucumbers, rays, green anemones, feather stars and sponges.

Observations of egg-carrying scorpionfish indicate ongoing breeding cycles.

The Marmara Sea sustains diverse habitats at various depths due to converging waters from the Mediterranean, Aegean and Black Seas, Karail said.

Human activities like heavy fishing and urban waste threaten this ecosystem.

“We do not want to say to our children and grandchildren, ‘This used to be a sea,’” he said, urging the public to stop polluting the waters.

The Marmara Sea, an inland body of water entirely within Türkiye, connects the Black Sea to the Aegean Sea. It has faced severe ecological challenges recently, including a massive marine mucilage outbreak in 2021 caused by agricultural runoff and untreated wastewater.