The marine fish food web is globally connected

Area of Science:

• Marine Ecology
• Network Theory
• Biogeography

Background:

• Marine ecosystem productivity relies on complex predator-prey interactions within trophic networks.
• Oceanic scale challenges direct sampling of marine feeding networks, necessitating data-driven inference.
• Species extinction can trigger cascading effects throughout marine food webs.

Purpose of the Study:

• To investigate the global structure of marine fish food webs and the distribution of trophic interactions.
• To test the hypothesis that species range heterogeneity concentrates interactions in warmer regions and specific species groups.

Main Methods:

• Inferred a global metaweb of marine fish feeding links based on co-occurrence data.
• Analyzed network structure in relation to geographic distribution and sea surface temperature.
• Compared interaction redundancy in coastal versus open-water marine communities.

Main Results:

• The global marine fish metaweb exhibits high geographic connectivity and low spatial modularity.
• Network structure metrics correlate with sea surface temperature, peaking in tropical regions.
• Coastal food webs demonstrate greater interaction redundancy than open-water communities.

Conclusions:

• Marine ecosystems are broadly connected but possess inherent robustness to perturbations.
• High interaction redundancy in coastal areas may enhance resilience to species extinction events.
• Global patterns of trophic interactions are influenced by temperature and species distribution.