Do lobsters eat sardines?
Lobsters eat live food fish, molluscs and other invertebrates.
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A predator-prey relationship near where I live is dolphins-tuna-sardines. Dolphins are predators that hunt and eat tuna, who are the prey of dolphins. The tuna are also predators, but they hunt and eat sardines, who are the prey of tuna. So dolphins know to look for tuna where they see sardines, but they do not prefer to eat the sardines.