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Breeding and Maturation: How do you tell a male sea horse from a female? Look for the pouch. If it has a pouch, it is a male, though the pouch is not always easy to see when the male is not pregnant. The female sea horse lays from 12 to 100 eggs in the pouch of the male sea horse. As the eggs attach to the lining of the pouch they are fertilized. The male will nourish them while they are in the pouch. The male gives birth after a 14 to 28 day gestation period. Left on their own at birth, it is thought that only 2 out of 1,000 make it to adulthood.
Baby sea horses often form small groups or rafts by holding onto each other’s tails. After birth, the male usually becomes pregnant again. In tropical waters, sea horses breed year around. In temperate waters they breed in spring and summer. Sea horses mate for life. This has added to the decline of sea horses in the wild. The natural predators of juvenile sea are piscavores, any fish-eating fish. Adult sea horses have few predators. Storms play a role in some sea horse mortality, as they tear the sea horse away from their holdfast, throwing them onto a beach, or they may die from exhaustion. Seahorse lifespan is thought to be three to five years in the wild, though it varies by species.
Diet: Sea horses eat constantly. They have no stomach, but a simple digestive tract. They feed on plankton and other larval animals.
Conservation Notes/Status: As of 2003, the United States and 151 other nations are involved in the trading of sea horses. Each year millions of sea horses are taken for traditional Chinese medicine, the pet trade and souvenirs. This has taken a major toll on the sea horse population. In the past 5 years the sea horse population is believed to have declined by 50 percent. The largest importers are China, Hong Kong and Taiwan. The largest exporters are Thailand, Vietnam, India and the Philippines. Sea horses are specifically sought in some commercial fishing efforts, however they are often taken as a by-catch product of the shrimp and prawn trawl boats. Unlike many by-catch species that are caught and discarded, dead sea horses are a very valuable by-catch, worth a great deal of money. Sea horses are particularly susceptible to over-fishing for several reasons.
Sea horses are monogamous, but will seek a new mate if one is lost. However, sparse distribution of horses and over-fishing makes it hard to find another mate. The brood size is small. Pregnant sea horses are often harvested, with the adult as well as unborn sea horses lost. Little is known about the biology of sea horses and very few studies have been conducted on sea horses in the wild. It is hard for scientists to determine how many sea horses can be taken from the wild and still have a viable wild population. The habitat destruction of the grass beds and mangrove swamps has also added to the population decline.
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