page_title: Seahorse
section_title: Feeding habits
hierarchical_section_title: Seahorse / Feeding habits
caption_attribution_description: Seahorse (Hippocampus erectus). Taken at the New England Aquarium (Boston, MA, December 2006. Copyright &#169; 2006 Steven G. Johnson and donated to Wikipedia under GFDL and CC-by-SA.
context_page_description: Seahorse is the name given to 46 species of small marine fish in the genus Hippocampus. "Hippocampus" comes from the Ancient Greek hippokampos, itself from hippos meaning "horse" and kampos meaning "sea monster". Having a head and neck suggestive of a horse, seahorses also feature segmented bony armour, an upright posture and a curled prehensile tail.
context_section_description: Seahorses use their long snouts to eat their food with ease. However, they are slow to consume their food and have extremely simple digestive systems that lack a stomach, so they must eat constantly to stay alive. Seahorses are not very good swimmers, and for this reason they need to anchor themselves to seaweed, coral or anything else that will anchor the seahorse in place. They do this by using their prehensile tails to grasp their object of choice. Seahorses feed on small crustaceans floating in the water or crawling on the bottom. With excellent camouflage seahorses ambush prey that floats within striking range, sitting and waiting until an optimal moment. Mysid shrimp and other small crustaceans are favorites, but some seahorses have been observed eating other kinds of invertebrates and even larval fish. In a study of seahorses, the distinctive head morphology was found to give them a hydrodynamic advantage that creates minimal interference while approaching an evasive prey. Thus the seahorse can get very close to the copepods on which it preys. After successfully closing in on the prey without alerting it, the seahorse gives an upward thrust and rapidly rotates the head aided by large tendons that store and release elastic energy, to bring its long snout close to the prey. This step is crucial for prey capture, as oral suction only works at a close range. This two-phase prey capture mechanism is termed pivot-feeding. Seahorses have three distinctive feeding phases: preparatory, expansive, and recovery. During the preparatory phase, the seahorse slowly approaches the prey while in an upright position, after which it slowly flexes its head ventrally. In the expansive phase, the seahorse captures its prey by simultaneously elevating its head, expanding the buccal cavity, and sucking in the prey item. During the recovery phase, the jaws, head, and hyoid apparatus of the seahorse return to their original positions.
  The amount of available cover influences the seahorses feeding behaviour. For example, in wild areas with small amounts of vegetation, seahorses will sit and wait, but an environment with extensive vegetation will prompt the seahorse to inspect its environment, feeding while swimming rather than sitting and waiting.  Conversely, in an aquarium setting with little vegetation, the seahorse will fully inspect its environment and makes no attempt to sit and wait.
caption: Seahorses (Hippocampus erectus) at the New England Aquarium
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