Understanding who eats whom in the ocean just got a lot more precise. Scientists at the Helmholtz-Zentrum Hereon in Geesthacht, Germany, have developed a revolutionary computer model that accurately simulates marine food webs, offering new insights into the effects of climate change, overfishing, and other environmental threats. Published in the prestigious journal Nature Ecology & Evolution, this innovative model marks a major advancement in marine ecosystem research and conservation.
Why Traditional Food Web Models Fall Short
Until now, marine biologists and ecologists have struggled to model predator-prey interactions accurately. Existing models—either species-specific or size-based—have critical limitations. According to Dr. Ovidio Fernando García-Oliva, lead author and ecosystem modeler at Hereon, species-specific models require vast amounts of data on what each marine organism eats. Unfortunately, for many sea creatures, such data is lacking. On the other hand, conventional size-based models operate on a simplistic rule: predators eat prey five to ten times smaller than themselves. However, this only reflects about 50% of marine species interactions, leaving a huge gap in predictive accuracy.
A New Model for Realistic Marine Food Web Simulations
Dr. García-Oliva, alongside Prof. Kai Wirtz, head of the ecosystem modeling team at Hereon, addressed these gaps by introducing two new prey-predator strategies into a refined size-based model:
- Predators targeting significantly larger prey, such as orcas preying on larger whales.
- Predators consuming much smaller prey, regardless of their own size—like baleen whales filtering krill or small crustaceans feeding on organic particles.
These two feeding strategies, found across fish, crustaceans, jellyfish, and marine mammals, now allow researchers to simulate up to 90% of predator-prey relationships in marine ecosystems.
Key Benefits for Marine Conservation and Climate Research
The enhanced model offers a powerful tool for predicting ecosystem responses to environmental stressors. It can simulate how marine food webs evolve under climate change, fishing bans, or the establishment of marine protected areas (MPAs). This makes it a valuable resource for policymakers, conservationists, and marine scientists.
“This model helps us understand how oceans function as complex ecological systems, enabling more informed decisions about marine conservation,” says Prof. Wirtz. “It’s also crucial for evaluating the long-term impact of human activities on biodiversity and food security.”
Marine Ecosystem Management Powered by Data
The Hereon team’s research not only sets a new standard for ecosystem modeling but also contributes to sustainable ocean management. The ability to predict how marine habitats will react to conservation measures provides a foundation for effective marine protected area design, ensuring healthier oceans for future generations.
Reference:
García-Oliva, O. F., & Wirtz, K. (2025). The complex structure of aquatic food webs emerges from a few assembly rules. Nature Ecology & Evolution. DOI: 10.1038/s41559-025-02647-1
Provided by: Helmholtz Association of German Research Centres
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