Jun 23

Seahorse Dads Do It All

Syngnathidae is the family of fish that includes seahorses (as well as leafy seadragons and pipefish). The name is derived from the Greek, meaning “fused jaw” – but their jaw is sooooo not the most interesting thing about them.

Where syngnathidae really shine is in the reproductive arena. They are the only animals on the planet where the males carry and birth their young.

“When seahorses are ready to mate, they have this ritual where they do a little dance,” says Kevin Juszyk, aquarist at Omaha’s Henry Doorly Zoo and Aquarium. “The male shows the female his open pouch, and the female transfers her eggs into it. The male fertilizes the eggs internally, goes through the pregnancy and then delivers a shower of a thousand baby seahorses.”

Seahorses also tend to be monogamous and mate for life but -- despite how involved seahorse dads are in the birthing process -- that doesn’t make them eligible for any Father of the Year awards. “Once the father gives birth, the babies are on their own,” Juszyk says. “They drift around until they’re able to use their tails to latch on to something.”

This makes for rather high mortality rates in the ocean, particularly given ocean warming, habitat destruction and over-harvesting (dried seahorse is used for medicinal purposes in some cultures). But Juszyk says that baby seahorses in an aquarium setting are much more likely to make it to their full life expectancy of about five years.

And even though parent seahorses are not big on nurturing their young, they do tend to stick together in groups, which are actually called herds. “They grab on to each other by the tails and stay hitched together so they don’t lose each other,” says Juszyk. “And in the mornings, they do their little dance. They circle each other and go up together in the water column. It’s really cute.”