White's Seahorse

Story and Photo by David Harasti

The White's Seahorse (Hippocampus whitei) is a shy species that belongs to the syngnathidae family that includes pipefish, seahorses and seadragons. The scientific genus for seahorses is 'Hippocampus' which also means 'horse sea-monster' in Greek. This species is endemic to the waters of New South Wales, Australia; endemic meaning that it is only known from this area. It can be found from Sydney to Port Stephens and is common on the protective shark mesh nets and pylons within Sydney Harbour.

The White's Seahorse has an elongate bony body and long snout that it uses to suck up small prey such as mysids. They swim slowly upright in the water, or wrap their tails around objects such as seagrass fronds or sponges to hold them in place for feeding or for stabilisation during turbulent water conditions such as storms.

Did you know that the seahorse is considered the slowest moving fish species in the ocean?!

The White's Seahorse uses camouflage to blend in with their surroundings before using an ambush predatory feeding behaviour on small crustaceans. Their colouration varies considerably and generally matches the colour of the plant or sponge that it is living on. The White's Seahorse is also known to be very territorial, there is a pair in the Port Stephens Aquatic Reserve that have been living on the same sponge for over two years.

The reproductive strategy shared by seahorses is unique in that the female deposits eggs in the male's body for incubation and the male then gives birth. The male Whites Seahorse carries eggs in pouch-like openings or beneath their tails and only the males care for the young. In seahorses, pregnancy lasts about two weeks to one month, the length decreasing with increasing temperature. At the end of gestation the male goes into labour (usually at night), pumping and thrusting for hours to release his brood. Young are miniature adult seahorses, independent from birth, and receive no further parental care. Newborns of most species measure between 7 and 12 mm. Most males give birth to around 100 - 200 babies.

The White's Seahorse has just become a protected species in NSW waters. As of July 2004 all species of the families 'Sygnathidae', 'Solenostomidae' and 'Pegasidae' have been listed as 'protected' under the NSW Fisheries Management Act 1994. It is now an offence to collect or harvest any seahorse, seadragon, pipefish, pipehorse, ghostpipefish or seamoths species in NSW waters without a permit. It is illegal to catch and keep or possess syngnathiformes, (or any other protected species in NSW) without a permit or licence, and heavy penalties apply. For corporations, these penalties can include fines of up to $55,000 while in other cases they can include fines of up to $11,000 and up to 3 months in prison.

David Harasti's website: www.daveharasti.com

This article was originally published in Scubadiver Australasia