University of Miami Rosenstiel School of Marine and Atmospheric Science
DAMSL - Digital Atlas Of Marine Species & Locations
New Search

Seahorse Information

Seahorses are a type of fish belonging to the genus Hippocampus.  In ancient Greek, the name translates to “horse/sea monster.”  There are believed to be at least 54 different species of seahorses.  However, due to the seahorse’s ability to change its color patterns and shape to camouflage itself, there has been a lot of difficulty with identifying individual species.  They are a marine species found in tropical seas such as Papua New Guinea, Bonaire, Myanmar and Thailand, as well as colder waters such as in New Zealand, Argentina, Eastern Canada and the United Kingdom.  Seahorses possess a dorsal fin and pectoral fins, but no caudal fin.  They have a prehensile tail, and a neck and snout that point downward.  Instead of scales, they are covered in hard external, bony plates that are fused together with a fleshy covering.  Their eyes are capable of moving independently from one another.  Seahorses are poor swimmers that have to beat their dorsal fin 30-70 times per minute to propel themselves and use their pectoral fins for steering and maneuverability.  Because they are slow, their method of hunting involves using their toothless snout as a vacuum to consume shrimp, fish, plants, plankton, amphipods, copepods, polychaetes and gastropods.  If something is too big, their snout can expand.

Their courting behavior is complex with dances and colors changes.  The males will also inflate their pouch to let the female know they are ready to mate.  Seahorses mate seasonally or for life depending on the species.  These generally monogamous fish greet each other daily with a dance for the purpose of checking to see if their mate is still alive, reinforcing their bond and synchronizing reproductive cycles.  The males are the ones that give birth among these fish.  The female deposits her eggs via her ovipositor into the male’s brood pouch for fertilization.  A capillary network in the brood pouch provides oxygen to developing embryos for about two to four weeks.  When the time comes, the males will anchor their tails to something and sway back and forth until all of the offspring are released.  Baby seahorses look like miniature versions of a fully developed adult and can swim freely.

Depending on the species, seahorses can live one to five years.  Only one in a thousand babies will reach adulthood.  The seahorses’ camouflage protects them well from predators such as dolphinfish, tuna and sharks.  However, all species within the genus of Hippocampus were listed in Appendix II of CITES (Convention on International Trade in Endangered Species) in 2002.  Species like the lined seahorse have been listed as “vulnerable” by the World Conservation Union (IUCN) Red List.  The issue is seahorses are popular among humans as ornamental display, fish for aquariums and ingredients in traditional Chinese medicine.  In addition to this, seahorses appear as bycatch in trawls and are very susceptible to habitat degradation via coastal development and marine pollution.  Seahorse trade regulations and sometimes suspension are current efforts being implemented to protect the species.

Leave a Comment