There’s no denying that seahorses are mesmerizing little creatures. They sport a head that resembles that of a horse. Have eyes like a chameleon, a pouch like a kangaroo and a prehensile tail like a monkey. Ready for their most unusual trait? A seahorse is the only the male who gets pregnant and gives birth in the animal kingdom.
Unique among fish for having bent necks and long-snouted heads, they mirror horses. They swim vertically, bony plates reinforce their entire body and they have no teeth, a rare feature in fish. Seahorses (genus Hippocampus erectus) move their fins very quickly similar to a hummingbird, but are notorious as one of the slowest swimmers on the planet. On the other hand, they are quite maneuverable and able to move up, down, forward and backward.
Those extraordinary looks and surprising social behavior have earned seahorses a mythic stature along the lines of unicorns. The aquatic creatures have been lionized in popular culture starring in cartoons and Disney movies such as The Little Mermaid and Finding Nemo. However, their universal appeal has worked against them. About 25 million seahorses are plucked from the wild each year for display or medicinal purposes.
Tiny in size and coming in a rainbow of colors, lined seahorses have been consistently listed as one of the most popular exhibit animals in zoos and public aquaria. Members of the pipefish family, seahorses boast specialized structures in their skin cells which allow them to change color to mimic their surroundings. The thumbnail-size pygmy seahorses are masters of camouflage and survive by attaching to vibrant corals where they become nearly invisible to both predators and researchers.
There are currently thought to be about 80 species of seahorses found throughout the world’s oceans. With their unique upright posture seahorses range in size from just over a half-inch for pygmy seahorses to 14 inches. Seahorses eat plankton and small crustaceans, but do not have teeth and stomachs so food passes quickly through their body. Seahorses are able to eat up to 3000 brine shrimp per day. Their range in the wild is about 40 meters, moving via their tails, which can flutter 35 times per second. Seahorses are diurnal, which means they are more active during the day.
Wild seahorses face many challenges such as loss of habitat through coastal development, pollution, and fisheries as well over-exploitation for traditional Chinese medicine. In the wild, only an estimated one in 1,000 newborn seahorses survives to adulthood. At Mote Marine Laboratory & Aquarium, easily 70 t0 85 percent of the seahorses survive - that's quite astounding for a species that gives birth every 28 days. At Mote they circulate around tanks where water is changed twice daily providing proper salinity and an exacting balance between acid and base, or pH.
From its humble beginnings in a tiny one-room building in 1955, Mote has evolved into a world-class research center that conducts ocean research on six of the world's seven continents. Located just north of Sarasota, Fla., Mote is also a working aquarium which gives visitors an up-close experience with a wide variety of marine animals and fish.
In an effort to support these unique aquatic creatures Mote has expanded its breeding facilities and opened the exhibit: "The Seahorse Conservation Laboratory" nearly a decade ago. Mote raises lined seahorses, which are often sent to aquariums all over the country, as well as pygmy seahorses utilized for conservation purposes. The project reduces the number that need to be collected from the wild. Lined sea horses are found in seagrass beds on Southwest Florida’s Gulf Coast.
"With our Seahorse Conservation Lab we get to show the public the science behind the scenes," explained Adam Dolman, curator of Fish and Invertebrates. “Before, our seahorse breeding facilities were largely inaccessible to the public. But now we’re excited to spotlight these tiny creatures and the excellent care they receive.”
Raised in the Pacific Northwest, as a youngster Dolman was always drawn to the ocean and surrounding wildlife. He went on to attend the University of Hawaii earning a degree in marine science.
At Mote, Dolman and his team help to support seahorse populations by breeding them, thus reducing the number that need to be collected from the wild. Nearly 40 percent of seahorses displayed in roughly 60 accredited U.S. aquariums and zoos were born at Mote.
Seahorses are thought to be monogamous and mate for life. They engage in elaborate courtship rituals, linking their tales in an intimate curl, called "hitching" and then get nose to nose. It may last for hours. The female deposits the eggs into a pouch on the front of the male’s body which he fertilizes. About 28 days later, he gives birth to baby seahorses called “fry.” The number of eggs can vary from 50-150 for smaller species to 1500 for larger species.
Once born, the Mote staff feed the babies live zoo plankton then slowly wean them to frozen foods. They swallow their food whole which may explain why seahorse develop narrow, straw-like mouths. Mote's seahorses are sold for $5 to $15 each depending on age of the creature. Retail they can be upwards of $50.
"By raising them from babies to adulthood, we help educate our visitors, provide animals for other aquariums and reduce the need to remove them from the wild for education purposes," said Dolman, who's worked at Mote for 10 years. "That just makes perfect conservation sense."
Future plans could call for Mote to develop research projects examining the nuances of sea horse communication-- the clicking and popping sounds made by rubbing two parts of their skull bone against each other that's performed during feeding and courtship.
"They are fascinating, magical creatures, one of the most popular exhibitions at Mote," Dolman related. "We have only just begun to scratch the surface of what we know. There's so much more work to be done."