Curious alien! Marine biologist shines spotlight on the Upside-Down Jellyfish in Maltese waters
Marine biologist Prof Alan Deidun has drawn attention to one of Malta’s lesser-known marine visitors – the Cassiopea andromeda, more commonly known as the upside-down jellyfish. First recorded in Maltese waters back in 2009/2010 by Patrick Vella, this species has since become a familiar yet unusual presence along our shores.
Classified as an invasive alien species (IAS), the upside-down jellyfish is also being studied for its potential biotechnological uses through the WASTE2TASTE project, while also being carefully managed within a protected nature reserve at Salina. Prof Deidun extended his thanks to BirdLife Malta for their collaboration, as well as Alessio Marrone, Neil Cutajar, and Laura Prieto for their contributions.
What makes this jellyfish so unique is its characteristic upside-down stance. By resting this way, it exposes the algae living in its oral arms to sunlight, enabling photosynthesis. In turn, the jellyfish benefits from the nutrients produced, supplementing its diet of small prey.
While generally harmless to humans, their sting, though mild, can still cause discomfort – so if you spot one, approach with caution or not at all!
Have you ever seen one?