New publication: Microbial degradation of jellyfish detritus promotes phytoplankton growth in coastal marine ecosystems

Researchers from the Marine Biology Station Piran, National Institute of Biology, have published a new study in ISME Communications revealing a previously overlooked link between decaying jellyfish blooms and phytoplankton growth.

Using controlled microcosm experiments, the team demonstrated that protein-rich organic matter released during the decay of the invasive comb jelly Mnemiopsis leidyi rapidly stimulates specialized marine bacteria. These bacteria efficiently remineralize jellyfish-derived organic matter, releasing inorganic nutrients that subsequently fuel phytoplankton growth and primary production.

The findings highlight that jellyfish blooms should not be viewed solely as ecological disturbances, but also as important drivers of microbial processes, nutrient recycling, and marine biogeochemical cycles. As jellyfish are expected to become increasingly abundant under future ocean conditions, understanding their interactions with marine microbes is essential for predicting ecosystem responses to climate change.

The study was published in ISME Communications:

Tinta T. et al. (2026). Microbial degradation of jellyfish detritus promotes phytoplankton growth in coastal marine ecosystems. ISME Communications. 2026. DOI: 10.1093/ismeco/ycag185.