Pilot fish golden trevally swimming closely next to the bull shark, carcharhinus leucas to hide away from the predators and eat the parasites for the shark, mutual beneficial relationship

carcharhinus trevally shark endangered underwater habitat species aquarium fish undersea sea conservation wildlife predator freshwater swim protected environment queensland parasite ocean eat australia threatened zambezi reserve zambi leucas mutualist hide marine water coast shelter wild nature coastal vulnerable bull mutual mutual benefit natural pilot world relationship river requiem gold golden