General Information about Sea Horses
Systematics
     Sea horses are members of the Teleost suborder, or bony fish.  They belong to the Family Syngnathidae and most are in the Genus Hippocampus.  Some other sea horse genera include Acentronura and Phyllopteryx.  There are about forty total species of sea horses in these three genera (Crowder 1928).  Four species are known to live in the United States.  These include:  Hippocampus zosterae, the dwarf sea horse;  H. reidi, the longsnout sea horse; H. ingens, the Pacific sea horse; and H. erectus, the lined sea horse (Matlock 1992).

Photo Courtesy of Donovan Gutierrez and Snap-Shot.com.
Habitat
     Sea horses usually occur in the tropics or along temperate coasts.  They prefer a vegetated habitat over open water because they are poor swimmers.  Regardless of whether or not prey are present, sea horses choose to stay in a vegetated environment.  In experiments by Flynn and Ritz (1999) the sea horses were found to prefer a habitat of a low-medium complexity, which was defined as 800-2400 blades of sea grass per square meter of sea water.  In a survey of the sea horses that occur along the coast of Great Britain, Garrick-Maidment (1998) found that the sea horses spent the warmer summer months in the shallow water.  During the winter the sea horses preferred to move into deeper water where they could overwinter to avoid the severe winter storms. 

Photo Courtesy of Michael McGrath and Snap-Shot.com.
Feeding
     Sea horses feed mostly on small living animals such as daphnia, cyclops, larvae of water insects, or mysids.  They hunt in an ambush style.  Sea horses have an increasing success in capturing their prey with increasing habitat complexity.  Adult sea horses tend to feed more optimally then juveniles.  This occurs because the adults learn to feed more efficiently by expending less energy with age.  Also the sea horses perform a head flick to grab their food.  The adults have an advantage over juveniles because they are larger.  The smaller juveniles must be closer to the prey to perform the head flick, and consequently the prey is more likely to notice the sea horse nearby and try to get away (Flynn and Ritz 1999).

Photo Courtesy of Donovan Gutierrez and Snap-Shot.com.
Behavior
     When sea horses are hungry, they move and hunt freely; however, most of the time they stay attached by their tails to sea weed (Flynn and Ritz 1999).  Sea horses also tend to swim in pairs linked by their tales (Hunter 1931).  Their swimming tends to be weak because they are only able to use their one small dorsal fin in an undulating or vibrating motion.  They compensate for their slowness by blending into their environment very well.  This allows them to disappear quickly (Bohlke and Chaplin 1968).  Adult sea horses swim in an erect, upright manner, and juveniles swim more like the pipe fish in a horizontal manner with the head stretched forward and the tale behind them (Garrick-Maidment 1998).

Photo Courtesy of Donovan Gutierrez and Snap-Shot.com.
If you have any questions, please contact Leslie Cook.