A preliminary comparison of the trophic structure of some large marine ecosystems Rainer Froese, IfM Uwe Piatkowski, IfM Stefan Garthe, FTZ Daniel Pauly, UBC

Overview Need to Understand Marine Ecosystems Available data: species composition, trophic level of species Approach: compare trophic signatures between groups of organisms and between ecosystems

Hypotheses Hypothesis I: A given taxonomic group will have similar signatures in similar ecosystems Hypothesis II: Different taxonomic groups will have different signatures

Number of Marine Fish Species by Trophic Level

Trophic Signatures of Fish Species: Tropical LMEs

Trophic Signatures of Fish Species: Tropical and Temperate, Brackish LMEs

Trophic Signatures of Fishes in Five LMEs

Mean Max Length of Fishes by Trophic Level

Trophic Structure of Fish, Birds, Cephalopods and Marine Mammals in the North Sea

Trophic Pyramid by Species Numbers for the North Sea

Conclusions Species Composition of Ecosystems and Trophic Signatures are Long-term Characters Trophic Signatures Can be Used to Classify Groups of Organisms and LMEs Strong Separation between Vertebrates and Invertebrates at Troph 3 Finer Resolution Needed for Lower Levels

Thank You We thank the FishBase team for encoding much of the data used in this study and for programming the various tools (TrophLab, Trophic Pyramids). Data and tools are available at