16/09/2026
When the Baltic Sea heats up, who eats whom? 🦐 🦀 🐙
In the coastal Baltic Sea, bladderwrack forms underwater habitats that provide food and shelter for small animals such as snails, isopods and shrimp. These animals are connected through an invisible web of feeding relationships. When heatwaves strike, do predators such as shrimp eat more to meet their increased energy needs, switch prey or struggle to find enough food? And how do these changes ripple through the food web?
🔥 Marine heatwaves, periods of unusually warm seawater, are becoming more frequent, intense and prolonged with global warming, threatening coastal biodiversity and ecosystem functioning.
🔥 Marine heatwaves do more than put individual species under stress. They can change how species interact, including who eats whom, potentially rewiring entire food webs. These relationships help determine how ecosystems function, how stable they are, and how they respond to future heatwaves.
➡️ A group of researchers at Tvärminne Zoological Station led by Academy Research Fellow Susanne Kortsch and postdoctoral researcher Ze Hui Kong are investigating these questions by studying how coastal communities respond to marine heatwaves. Professor Christian Pansch at Åbo Akademi is a collaborator in this research.
➡️ Bladderwrack and its associated organisms were transferred from the nearby coast into large experimental tanks, then exposed them to heatwaves of different intensities. The experiment was repeated in early and late summer to explore whether the seasonal timing of a heatwave matters.
➡️ The researchers are measuring changes in the abundance and biomass of organisms, alongside key ecosystem processes such as decomposition and oxygen production and consumption. They will combine these observations with food web modelling to explore how warming could rewire feeding relationships and alter ecosystem functioning.
🔥 As marine heatwaves become more frequent and intense, understanding these hidden ecological connections can help anticipate the future of coastal Baltic Sea ecosystems.
💎With the kind support of