Generalized trophic pyramid for the tropical Pacific Ocean

Figure 4-2  The base of the food web consists of bacteria, small phytoplankton, and protists (nanozooplankton), 0.2 to 20 μm in size. These organisms are ingested by zooplankton, such as crustaceans, molluscs, or tuna larvae, up to a size of 2,000 μm. In turn, zooplankton are consumed by macrozooplankton, such as jellyfish, and micronekton, such as squid, shrimp, and small fish. Micronekton and, to a lesser extent, macrozooplankton are the prey for tuna and other large pelagic fish at the top of the pyramid. (From Le Borgne et al., 2011.)