Jellyfish: if you can’t beat them, eat them?

Kerteminde is a charming harbour town in Central Denmark with a stunning fjord surrounded by fields, hills, and forests.

It’s a haven for marine wildlife, but scientists from the University of Southern Denmark (SDU) are intrigued by one mysterious species - jellyfish.

The species is booming just beneath the surface of the water, where this group of scientists jump into. In their snorkelling dive, they observe the jellyfish and collect samples.

These sea jellies aren't very stingy, but their biomass here is so dense it harms other species.

Around the world, jellyfish sting tourists, clog fishing nets, and block water pipelines.

There are even fears that they might replace all other sea species.

But Jamileh Javidpour, who has been studying jellyfish for over 20 years, says we don't know enough yet to make such predictions.

“Apocalyptic scenarios of jellyfish bloom are existing, and there are partly true stories because the presence of jellyfish might affect the entire ecosystem,” explains Jamileh Javidpour, associate professor at SDU.

“However, changes in the entire population need a kind of holistic view — what is the effect of other populations that are connected to this player of the food web together? So we need a kind of adaptive view to jellyfish bloom, which is still not existing.”

Back on the boat, scientists sample water characteristics and use a dip net to collect more jellyfish samples.

Researchers monitored water temperatures, salinity, and other factors to better understand the causes of jellyfish blooms.

It appears jellyfish thrive due to overfishing, which removes their predators and competitors, and agricultural runoff that depletes oxygen in the water.

Unlike other species, jellyfish aren’t bothered by low oxygen