Sea Horse (Hippocampus)


Class: Osteichthyes
Order: Gasterosteiformes
Family:    Syngnathidae
Size:    Length: 1 to 14 inches (2.5 to 36 cm), depending on the species
Weight: Unknown
Diet: Plankton and brine shrimp
Distribution: Atlantic coasts of Europe and Africa, Atlantic & Pacific coasts of North America
Young:  50 to 1,500 sea ponies
Animal Predators:  Crab, tuna, cod, sea perch, skates, rays
IUCN Status: Vulnerable to Endangered
Terms: Young: Sea pony
Lifespan: An average of four years in the wild



·         Sea horses need a high intake of food to survive.

·         Their eyes can move independently of each other.

·         The scientific name is derived from Greek, meaning hippo—horse, campos—sea monster.

·         Sea horses resemble the horse-shaped chess piece (knight).

·         The coronet, a structure on the top of the sea horse’s head, is nearly as unique as a human thumbprint. 

·         The sea horse’s dorsal fin can flap up to 35 times a second.



The name for these fish comes from their head’s similarity to that of a horse. Sea horses can change colour as camouflage to match their surroundings or even to match their mate. Sea horses have a tubular snout that they use like a straw, sucking in food and water. Their body consists of bony plates that form body armour arranged in rings around the body and tail, making this fish not a favourite with predators, due to the amount of bones. Males are easily distinguished from females, because of the males’ abdominal pouch.



Sea horses are found off the coasts of Europe, Africa and North America in shallow, warm water close to land. 


Feeding Habits

Sea horses wrap their tails around plant stems to hold themselves in place while eating or when water currents threaten to sweep them away. They feed on plankton, sucking it in through their snouts. Sea ponies may feed for up to 10 hours each day. 



The male seahorse offers his breeding pouch to the female, opening the pouch wide. The female moves her body to the pouch opening and fills it with up to 1,500 orange eggs. He then carries and incubates the fertilized eggs until they hatch, about 40 or 50 days later, depending on the species. The sea ponies are born live, taking from less than one hour to up to two days for all of the eggs to hatch. When it is time for the incubated young to be born, the father holds fast to a plant stem or some other object with his tail. He bends rapidly backward and forward until the pouch opens and a baby seahorse pops out. The infant seahorses emerge headfirst and are swimming, independent miniatures of their parents. If any of the babies are stillborn and remain in the pouch, the male may die within days from a bacterial infection. Sexual maturity is reached at four months of age. 



These friendly, loyal fish are monogamous and will hold tails while courting, forming a “V” with their bodies. Each morning sea horses greets their mate warmly, doing what appears to be a dance. If a sea horse’s mate dies or disappears, it is slow to find a new mate. All sea horses use their pelvic and pectoral fins for steering. They swim slowly in an upright position and take frequent breaks. Juveniles often form groups by holding onto each other’s tails.  



Sea horse populations are reported to have dropped by 50 percent in the last few years, mainly due to loss of habitat and demands in Asian markets for their use in medicinal products. The Knysna Seahorse (Hippocampus capensis) is listed as Endangered on the IUCN’s Red List and 30 more sea horse species are listed as Vulnerable. 



Sea Horse Wildlife Fact File, IM Pub, US