Newcomers in the Marmara: Fried Egg & Barrel Jellyfish in Mudanya

This month, residents of Mudanya witnessed something rare along their shores: jellyfish species that many had never seen there before. Among them were the Barrel Jellyfish (Rhizostoma pulmo)—large, bluish creatures often seen in Istanbul waters—and the Fried Egg Jellyfish (Cotylorhiza tuberculata), with its golden “yolk” center that makes it look just like breakfast on the waves.

For locals who have lived by the sea for over a decade, this was the first time they’d seen these species in Mudanya. Some individuals reported up to four large jellyfish washed ashore in a single day.

Photo: The Marmara Project

Why Does It Matter?

The appearance of new jellyfish in the Marmara tells us something important: our seas are changing. Warmer waters, shifting currents, and declines in natural predators (like turtles and fish) all make jellyfish blooms more likely. When unfamiliar species arrive in new areas, it’s often a sign of larger ecosystem shifts.

Are They Dangerous?

• Barrel Jellyfish → Mildly venomous; their sting is usually harmless to humans but can still cause irritation.

• Fried Egg Jellyfish → Harmless; many swimmers in the Mediterranean brush past them without even noticing.

• Important Note: Even when washed up on the beach, jellyfish can sting for days after death. It’s best not to touch them.

Why Citizen Science Matters

These discoveries weren’t made by researchers with boats and equipment—they came from everyday people living by the sea. By sharing photos and reports, participants in the Marmara Project are helping to build a living record of how the Marmara Sea is evolving.

Each sighting adds a piece to the puzzle, showing us which species are arriving, which are thriving, and how our sea is transforming before our eyes.

Photo: Getty Images

What Can Be Done?

The Sea of Marmara is showing us urgent signs of stress, but the story is not finished. Every observation—from washed-up jellyfish to changes in water clarity—helps researchers and communities better understand what is happening beneath the surface.

You can play a role in this work:

• Submit an observation report if you encounter unusual marine life, pollution, or signs of ecosystem change.

• Support our research through donations, which allow us to continue documenting and analyzing these shifts.

Together, we can build the knowledge needed to protect the Marmara and restore its resilience.