Seahorses are common on Chek Jawa but are superbly camouflaged and thus often overlooked. Some may be as large as 11cm, but there are tiny ones too. A seahorse is actually a fish! Instead of scales, the seahorse has an inflexible armour of overlapping bony plates. Lying just beneath its skin, these plates encase the seahorse. Like other fish, it also has an internal skeleton. It lacks a tail fin and pelvic fins. It swims slowly by beating its dorsal fins, and uses the tiny pectoral fins on its 'cheeks' to stabilise itself. Adapted to calm waters with lots of hiding places, a seahorse cannot swim fast. A seahorse can make a short burst of speed when in danger, but most of the time it swims extremely slowly or remains stationary. Instead, it relies on camouflage to hide from both predators and prey. It uses its flexible, muscular tail to hang on to vegetation and other supports. It can also change colours to match its surroundings. Some species have flaps and projections out of their body to match the vegetation around them. Seahorse food: It may be hard to imagine of such a seemingly harmless creature, but the seahorse is a voracious predator. It sits-and-waits in ambush to prey on tiny animals that drift or wander by. These are sucked up in its toothless jaws and swallowed whole. 'Syngnathus' means 'fused jaws' in Greek. A seahorse needs to eat a lot continuously because its digestive system is simple and it does not have a stomach. Even a baby seahorse can eat thousands of tiny shrimp in a day! The seahorse has highly mobile eyes that can move independently of each other to look out for predators and prey without moving its body. Like other predators, seahorses are often territorial. Pregnant Fathers: Seahorses reproduce in a peculiar way. It is male that carries the eggs in his body and thus becomes 'pregnant'. The female lays her eggs in his pouch using a tube that looks very much like a penis. Inside his pouch, the eggs are fertilized and become embedded into the body walls. The blood vessels in the pouch provide the eggs with oxygen and nutrients. The production of these nutrients is stimulated by prolactin, one of the hormones that affect pregnancy in mammals. Emerging from the eggs, the babies hatch as miniature seahorses and may remain in the pouch for a while before the father goes into 'labour' and ejects them out of the pouch. Once they leave his pouch, he does not look after them. In fact, his mate is often ready with another batch of eggs. So he is often constantly 'pregnant'! Some seahorses perform elaborate courtship dances, sometimes changing colours as they move and holding tails as they swim together. In the wild, some form mated pairs. Human uses: Seahorses are used in traditional Chinese medicine. Many species are also caught for the live aquarium trade or dried and sold as cheap curious and souvenirs. Status and threats: Seahorses have few natural predators. Being virtually skin and bones, they don't make particularly good eating. Humans are the main threat to seahorses. Seahorse habitats are affected by reclamation, pollution and activities that increase sedimentation. Over-collection is another threat. Seahorses are naturally uncommon because they reproduce slowly and seldom travel far from one spot. Those faithful to their partners may take some time before taking on a new mate. Usually, in the wild only a handful of babies survive from each batch of eggs. Being slow swimmers without a free-swimming larval stage, seahorses don’t spread quickly to new places. Being slow-moving and defenceless, seahorses are easily collected. Like other fish and creatures harvested for the live aquarium trade, most die before they can reach the retailers. Without professional care, most die soon after they are sold, often from starvation as their keepers do not provide the correct food in sufficient quantities. Those that do survive are unlikely to breed successfully. Efforts to farm seahorses have had limited success and often merely involves the equally destructive collection of pregnant males.

• Tan, Leo W. H. & Ng, Peter K. L., 1988. A Guide to Seashore Life. The Singapore Science Centre, Singapore. 160 pp. online version
• Lim, Kelvin K. P. & Jeffrey K. Y. Low, 1998. A Guide to the Common Marine Fishes of Singapore. Singapore Science Centre. 163 pp. online version
• Lim, S., P. Ng, L. Tan, & W. Y. Chin, 1994. Rhythm of the Sea: The Life and Times of Labrador Beach. Division of Biology, School of Science, Nanyang Technological University & Department of Zoology, the National University of Singapore. 160 pp.
• Kuiter, Rudie H., 2000 (English edition). Seahorses, Pipefishes and their Relatives: A Comprehensive Guide to Syngnathiformes. TMC Publishing, UK. 240 pp.
• Aw, Michael, 2000 (revised edition). Tropical Reef Fishes: A 'Getting to Know You' and Identification Guide. OceanEnvironment Ltd, Australia. 160 pp.
• Sparks, John, 1999. Battle of the Sexes in the Animal World. BBC Worldwide, London. 224 pp.

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