Male seahorse giving birth to hundreds at Florida Oceanographic Society

HUTCHINSON ISLAND — Thanks to a pregnant male seahorse found in an Indian River Lagoon crab trap, there are now hundreds of seahorses at the Florida Oceanographic Society.

That's not a typo: Female seahorses impregnate males, the males carry the embryos and give birth.

The male seahorse found in spring 2015 by Brittany Biber, the society's animal care director, gave birth to a brood a couple of weeks after she brought it to the Coastal Center on Hutchinson Island.

Part of that brood was another male, which bonded with a female brought from a Vero Beach aquaculture lab in October.

The couple has been very productive. Beginning in early March, they've produced four batches of babies — the most recent Tuesday morning — with more than 100 offspring in each brood.

"So all our sea horses are bred in captivity," Biber said. "That's important to us. We try our best to limit the number of animals we obtain from the wild in order to minimize our impact on the environment."

FOS has sent about 35 seahorses born on site to other environmental education nonprofits, including the Martin County School District's Environmental Learning Center in Jensen Beach and the Smithsonian Marine Station in Fort Pierce.

Native, but rare

The specimens are a species known as "lined seahorses" native to the lagoon.

More: You can lead a seahorse to water, but ...

Seahorses used to turn up periodically in lagoon seinings the society's staff does during environmental education classes with students, said Education Director Zack Jud.

"We haven't had a seahorse turn up in seine in a couple of years, since 2016," said Jud, who finally saw a wild seahorse while fishing in the lagoon a couple of weeks ago near Fort Pierce.

Biber said she hasn't seen a seahorse in the lagoon since she found the pregnant male in 2015.

Seahorses in the lagoon are imperiled because sea grass in the lagoon is imperiled. The disappearance of the lagoon's seahorses coincided with 2016's Lake Okeechobee discharges that blanketed much of the St. Lucie River and parts of the southern lagoon with a blue-green algae bloom.

"Sea grass beds are the seahorses' habitat," Biber said. "They don't eat the grass, but they eat animals that do. The loss of sea grass we've seen in the lagoon is bad news for seahorses."

The seahorses aren't being raised to replenish the lagoon's stock. First, the society doesn't have the permit needed to do that. Second, releasing seahorses into a lagoon with little or no sea grass would be a death sentence.

More: Girl bitten by shark asks FWC to 'make beaches safe for kids like me'

"I'm sure some predator fish in the lagoon would be OK with it," Biber said.

About 30 of the young seahorses are on display at the Coastal Center with their two parents.

A couple of other seahorse couples could start producing broods soon.

Strong bond

"Once a pair bonds, they won't split up," Biber said. "When they're starting to bond, they do a courtship dance where they lock tails. Basically, they're getting on each other's birth cycles so that they have healthy broods."

Seahorses are among only a few animal species in which the male bears the unborn young. Pipefish, also found in the lagoon, are another.

Male pregnancy frees the female to make more eggs quickly and reproduce more often.

More: Do Indian River Lagoon, St. Lucie River fish you catch, eat have blue-green algae toxins?

But you probably want to know more about how males get pregnant and give birth:

The male and female align their stomachs, and the female squirts her eggs into a sack on the male's belly.

"Once they're inside, the male fertilizes the eggs," Biber said. "About 20 days later, he releases the babies, all of the perfect manifestations of their parents and ready to swim right away."

Like with many marine creatures, seahorses have a high mortality rate, Biber said. "Some are born weak, meant to be eaten by predators so that the stronger ones survive."

The center's seahorses are gray and black, although they can be a wide range of colors, Biber said.

They can grow to be 6 inches to 7 inches long eating tiny crustaceans, including larval shrimp and crabs.

"They'll eat just about anything smaller than their mouths," Biber said.

They don't chase prey. Instead, they usually attach to plants with their prehensile tails, then wait for tiny critters to swim by and suck them out of the water.

More: Vero Beach neighborhood now Florida-friendly to save Indian River Lagoon

Don't try this at home

Staffers at the center feed the seahorses live shrimp, including brine shrimp (aka "sea monkeys" like the ones once advertised in comic books) raised on high-calorie food by the staff and glass shrimp raised in the center's lagoon pond.

People can raise seahorses in their home aquariums, but Biber doesn't advise it.

"Aquarium food isn't enough to sustain them," she said. "Seahorses are designed to eat live food and eat it all the time. It's a lot more work than most hobbyists are going to want to take on."

Saddle up for some seahorse facts

There are about 40 known species of seahorses.

They swim upright and avoid predators by mimicking the color of underwater plants.

Except for crabs, few marine predators eat the seahorse; it is too bony and indigestible.

Because of their body shape, seahorses are rather inept swimmers and can easily die of exhaustion when caught in storm-roiled seas.

Each of their eyes moves independently, so they can follow passing prey without giving their presence away.

Seahorses have no teeth and no stomach. Food passes through their digestive systems so quickly, they must eat almost constantly to stay alive.

They can consume 3,000 or more brine shrimp per day.

Source: onekindplanet.org

See the seahorses