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A seahorse curling its tail around sea grassA seahorse curling its tail around sea grass Seahorses are small fish with horse-shaped heads and curled tails. There are 54 species of seahorse. They are found in shallow temperate and tropical seas across the world, living in sheltered areas such as estuaries, mangroves, coral reefs and seagrass meadows. Seahorses swim along in an upright position, propelling themselves using a small fin on their back. They are, however, poor swimmers so, in order to stop themselves from being swept away in fast-flowing water, they curl their long tails around plant stems. For protection, seahorses are camouflaged to match their surroundings, and can change colour in seconds. When danger approaches, they hide in nooks and crannies in the coral or among fronds of seagrass.They feed on small crustaceans that float or crawl within striking range. Males stay within a territory of between 0.5 and 1 square metres (5.5–11 square feet).

Pygmy seahorsesPygmy seahorses

A A "pregnant" male seahorse in an aquarium

Pregnant males

Seahorses are among the very few animal species on Earth in which the male bears the young. Before mating, the male and female perform a "dance" lasting several hours. The male then pumps water through the pouch on his belly causing it to open and display its emptiness. The female seahorse then lays her eggs into his pouch. There they develop for up to 45 days until the male “gives birth” to 50 or more fully developed, tiny baby seahorses. 

Baby seahorses are known as fry. Vulnerable to predators, less than one in a thousand will survive into adulthood.

The smallest species of pygmy seahorse, Satomi's, are less than 15 mm (0.6 inch) long. Most species have only been discovered since 2001.

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