Seahorse Males Give Birth

Wild and Aquarium Seahorses are Delicate Creatures

Dec 19, 2008 John Blatchford

Seahorse habitats are under threat, and peculiarities of their life-style make them particularly vulnerable to interference.

Divers should respect seahorse vulnerability, and hobbyists will do best with captive-bred animals in the aquarium.

Living Seahorses

There are about 30 living species of seahorse. Most live in shallow water associated with sea grasses, mangroves and coral reefs (all of which are under threat). They feed on small organisms such as plankton, which they suck out of the water one at a time. They are very poor swimmers so they normally remain close to the bottom, holding on with their prehensile tail.

Seahorses in the Marine Aquarium

Captive-bred seahorses survive best in the aquarium. They will usually eat dead food (while their cousins collected from the wild will only take living organisms), and they are less stressed by aquarium conditions. Captive-bred animals are more expensive, but since keeping them has no impact on the survival of seahorses in the wild, and since they will probably live longer in an aquarium anyway, hobbyists should be encouraged to demand captive-bred specimens. Because seahorses are slow movers and feeders they are normally kept in single-species tanks, although the addition of a few shrimps and maybe a goby or two would cause no problems.

Seahorses in the Wild

Wild seahorses maintain territories, with the males often moving no further than a metre from home. Females range a little further afield, giving them access to more food. Females seek out males, and after a long courtship the female lays her eggs on the male’s belly. Folds of skin cover these eggs (which the male has fertilised), so it is truly the male who gives birth! During gestation the mother ‘pops in’ each day – to see how things are coming along! – and when the male finally gives birth the female presents him with the next batch of eggs to take care of.

Small permanent territories, monogamous habits and long term pairing, as well as inhabiting parts of the marine environment that are themselves under threat means that seahorses are particularly sensitive to any interference by man. If divers have the chance to watch wild seahorses they should simply observe for a while and then move on – leaving the seahorses unmolested. Watch a short video of a diver/seahorse encounter.

British Seahorses

Two species of seahorse can be found in British waters, The Spiny Seahorse (Hippocampus guttulatus) and The Short Snouted Seahorse (Hippocampus hippocampus). They are both protected under the Wildlife and Countryside Act 1981.

In order to gather information about their distribution and population sizes divers and any other interested parties should report any sightings of British seahorses to The British Seahorse Survey.

Seahorses in Chinese Medicine

Millions of seahorses are caught each year, a small number for the aquarium trade, more as an accidental by catch while trawling for shrimp, and by far the most to supply the Chinese Medicine Industry. They are supposed to help with impotency problems.

So - seahorses are threatened in many ways. Divers and aquarists can help a bit, but the larger problems of habitat loss and overfishing will still be there. Maybe marine protected areas are the only way forward for the preservation of these charming and peculiar fish.

The copyright of the article Seahorse Males Give Birth in Marine Biology & Oceanography is owned by John Blatchford. Permission to republish Seahorse Males Give Birth in print or online must be granted by the author in writing.