The Seahorse: A Fish that Fascinates


The Seahorse: A Fish that Fascinates

They lack the fierce visage of a shark, the shimmering beauty of an angelfish and the playful personality of a river otter, yet seahorses inevitably fascinate The Florida Aquarium’s visitors, who linger among the exhibits where the animals live. two yellow seahorses cling peacefully to green grasses in an exhibit at the florida aquariumShawn Garner, Aquarium senior biologist, has a favorite explanation for the seahorse’s appeal:

“It’s unique. It’s got a head like a horse, a tail like a monkey, and a pouch like a kangaroo.”

Two green/brown colored seahorses anchor themselves to a piece of seaweed in a florida aquarium exhibitDespite its bizarre physical assemblage, the seahorse still somehow manages to convey beauty and grace. And, if its confounding appearance wasn’t other worldly enough, Garner revealed another oddity: The seahorse represents “the only true male birth in nature. Females deposit unfertilized eggs into the male’s pouch.” 

The male fertilizes the eggs, impregnating himself, and carries the eggs until gestation, which can be 10 days for smaller seahorse species and up to 25 days or more for the larger. They are busy little breeders too, mating continuously for four to six months during warm weather, with the males giving birth multiple times. Seahorses are sexually dormant during cooler months. Some species of seahorses are monogamous and mate for life.

The parents show no such commitment to their brood. The mother seahorse is “out of the picture” once she deposits the eggs. Despite his pregnancy, the male seahorse is no more concerned about parenting. Baby seahorses are on their own once hatched. Garner continued, “Once the babies are born, they go into the plankton and float around for about two weeks and then drop to the benthic (bottom) level, learning to use their tail to hold on to algae.”

Seahorses feed on small shrimp, fish larvae and such.  Garner said they need to eat all the time since they “don’t really have a stomach.” The seahorse is a “lie-and-wait predator and difficult to see” because it is camouflaged to blend with the sea grasses and mangroves it inhabits.

Seahorses are not as common in coral reefs, but those that do live in reefs can be spectacular. “In the Caribbean,” Garner said, “some may be yellow or orange to blend in with surrounding corals.”

 a video .gif of a brown seahorse Seahorses don’t travel much, moving only about “five to seven meters from its normal area.” There are roughly 42 species of seahorses, but an exact count is difficult because “new species are being found every year.”

Florida has three species: The lined seahorse, which can grow to more than seven inches, and the dwarf, which is less than an inch, are the most abundant in the Gulf of Mexico. The slender or longsnout seahorse, which can be seven inches long, is found primarily in South Florida. It has a more delicate build than the similar-sized lined seahorse.

Garner said seahorses can be found in grass flats throughout Tampa Bay, but their camouflage and stealth make them exceedingly hard to spot. Birds, fish and sea turtles will eat seahorses but they are not normally targeted because “they don’t have much meat and they are tough.”

Indeed, these flimsy-looking creatures are “built like a tank,” with a hard, protective frame. Garner noted that “the U.S. military is even using the seahorse structure in designing exoskeleton” suits for soldiers.

The Florida Aquarium has about a dozen seahorse species. These include seadragons, a flamboyant cousin to Florida’s seahorses. Native to Australia, the seadragon can grow to 18 inches and possess extravagant leafy appendages that resemble the kelp of their native habitat.

Garner said other seahorses also may develop such growths, called cirri, to replicate their surroundings, but none can rival the seadragon for showmanship. The seahorses and seadragons evolved from the pipefish, a small, thin fish whose snout resembles that of a seahorse. It is found in Florida waters and also is on display in The Florida Aquarium’

It may seem strange evolution led from the straight-bodied pipefish to the S-shaped seahorse, but Garner explained that curve actually allows the seahorse to strike prey further away.

While the seahorse is not considered a culinary prize by its marine neighbors, its numbers are shrinking alarmingly because an estimated 20 million are taken as bycatch by shrimpers each year. It is also used as medicine and in teas in China. And, unfortunately, it can still be sold as a curio in souvenir shops. (I regret buying one as a kid at a Tarpon Springs gift shop. Young visitors to The Florida Aquarium will leave more enlightened than I was.)

Garner said The Florida Aquarium breeds seahorses so they can be displayed in other aquariums without being taken from the wild. The task requires that the water conditions and habitat are perfect for the seahorses.  

While the Aquarium and other public aquariums and zoos have great success raising seahorse fry, the leafy seadragon has never been successfully bred in human care. Garner, who’s studied seahorses in Honduras and other countries, wants to change that. He’s conducted research that indicates moon phases affect seadragon mating, and is hopeful that a breakthrough is near.

The dwarf seahorse can live about a year in the wild; the larger seahorses may live four years. But they live longer, up to six years, in The Aquarium. “They live about 20 percent longer here because of the great care they receive,” Garner said.

That kind of TLC doesn’t occur in the ocean.

You may never see the elusive seahorse in the wild, but at The Florida Aquarium, you can get a close-up view of this weird and captivating marvel of nature. 


Story by Joe Guidry, former opinion editor, The Tampa Tribune



With contributions by:

Shawn Garner, Senior Marine Biologist, The Florida Aquarium




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