There are 32 species of seahorse, all in the genus Hippocampus. The aquarium is currently featuring "Seahorses: Beyond Imagination," an exhibit about seahorses, pipefish, and sea dragons that will end next year. Scarratt said it has been the most successful exhibit in the history of the Baltimore Aquarium, which opened in Although the bony plates covering its body make the seahorse unpalatable to most other animals, its survival is under threat from human predation, especially for use in traditional medicines.
No statistical data on seahorse populations is available because relatively little research on seahorses has been done until recently, but fishers have reported a decline in the number and size of seahorses they catch, according to a network of scientists from various institutions who conduct research under a program called Project Seahorse.
Breeding seahorses in captivity is a problem, in part because the babies are so tiny it's hard to keep them alive. The marine scientists in Baltimore are working to develop effective methods that will help ensure the creature's survival. The male seahorse has a pouch on its stomach in which to carry babies—as many as 2, at a time. A pregnancy lasts from 10 to 25 days, depending on the species.
The reproductive process begins when a male and a female seahorse do daily pre-dawn dances, intertwining their tails and swimming together. Eventually they engage in a true courtship dance, which can last as long as eight hours. It ends with the female depositing her eggs in the male's pouch. Scientists think the courtship behavior is designed to synchronize the movements of the two animals so that the male can receive the eggs when the female is ready to deposit them.
The eggs are then fertilized in the dad's pouch. The eggs hatch in the pouch. The father cares for the young as they grow, regulating the water salinity in the pouch to prepare them for life in the sea. When the tiny seahorses are ready to be born, the male undergoes muscular contractions to expel the young, known as "fry," from the pouch.
While seahorse dads go the extra mile to give birth, the parents do not provide their tiny offspring with any care or protection after they are born. Infant seahorses are susceptible to death from predators and being swept into ocean currents, where they drift away from feeding grounds rich in microscopic organisms.
Fewer than five infant seahorses in every 1, survive to adulthood, which helps explain why the litters are so large, said James Anderson, manager of the seahorse program at the National Aquarium in Baltimore. By fish standards, however, seahorses have a fairly high survival rate because they are sheltered in the father's pouch during the earliest stages of development.
The eggs of other fish are abandoned immediately after fertilization. Although seahorses are the only fish that experience true male pregnancy, the males of two close relatives, sea dragons and pipefish, carry eggs attached to an area beneath their tails. Anderson said other members of the family Sygnathidae, to which these three fish belong, have a number of different types of enclosed areas on their bodies in which to hold eggs; these spaces range from a flat spot to a trough, suggesting how a pouch may have evolved.
Because seahorses generally live in shallow, near-coastal waters, human activities including development, pollution, fisheries, and traditional medicine have reduced their numbers.
At the same time, their universal appeal has worked against them; until recently, wild seahorses were often captured for the aquarium trade. The delicate creatures tend to fare poorly in aquaria, however. In recent years, captive-bred seahorses have shown promise as hardier tank-dwellers than their wild relatives.
Home Ocean Facts Fact question. Seahorses can change colour very quickly and match any surroundings in which it finds itself. They have even been known to turn bright red to match floating debris.
Both males and females also change colour during their courtship display. Unlike most other fish, seahorses have an exo-skeleton. Their bodies are made up of hard, external, bony plates that are fused together with a fleshy covering. They do not have scales. Seahorses are poor swimmers. They rely on their dorsal fin beating at times per second to propel it along. Pectoral fins either side of the head help with stability and steering.
Seahorses live in shallow weedy areas especially eel grass beds. In winter they move into deeper waters to escape the rough weather. Seahorses are under threat worldwide for three main reasons: The Traditional Chinese Medicine Trade takes in excess of up to million seahorses a year from the wild and these are used for all types of medicine. The Curio Trade takes approximately one million seahorses from the wild.
Along with shells and starfish; they are deliberately taken from the sea and left to die in the boiling sun. They are then sold as souvenirs, a sad and sorrowful reminder of once beautiful creatures. The pet trade takes an estimated one million seahorses from the wild and It is thought that less than 1, survive more than six weeks. There are about 54 species of seahorses worldwide, and possibly as many sub-species.
It is often difficult for scientists to identify seahorses because individuals of the same species can vary greatly in appearance. New species continue to be found. The Seahorse Trust was set up in as an umbrella organisation to preserve and conserve the natural world, especially the marine environment using Seahorses as our flagship species.
We work in partnership through a Seahorse Alliance with many organisations and people from all over the world and it is this unique partnership that allows us to achieve so much in the conservation of seahorses and their environment for the future. E-mail: theseahorsetrust gmail.
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