by InTrieste
Visitors to the Gulf of Trieste were treated to a familiar summer sight on Saturday as several fried egg jellyfish were spotted in the waters off Sistiana by the InTrieste team.
The species, known scientifically as Cotylorhiza tuberculata, is easily recognized by its distinctive yellow dome, which resembles a fried egg. Belonging to the Cassiopea family, the jellyfish is a regular seasonal visitor to the northern Adriatic during the warmer months. Despite its unusual appearance, the species poses little threat to swimmers, with only a mild sting in most cases, making such sightings a common feature of summer along the coast.
According to Marina Lipizer, a researcher at Italy’s National Institute of Oceanography and Applied Geophysics (OGS), warm waters favor the species. Populations become more abundant when sea temperatures exceed about 20–22 degrees Celsius, while growth and reproduction increase further between 24 and 30 degrees.
Lipizer added that the warming Mediterranean is contributing to the northward expansion of several warm-water jellyfish species, including those in the Cassiopea genus. The trend is particularly evident in lagoons, ports and shallow bays, where water temperatures tend to rise more quickly than in the open sea.
