I made a surprising discovery a few months ago. There are seahorses in the Hudson River.
I repeat: There are seahorses in the Hudson River.
Beautiful, Strange, But Not Mythical
I learned this eye-opening fact while visiting the River Project’s Wetlab on Pier 40. The River Project is a marine science field station working to conserve habitats and wildlife in New York Harbor and the Hudson estuary.
Since 1988, the River Project has surveyed and monitored the waters off the piers of Hudson River Park. They discovered 50 fish species beneath the murky, brackish currents of the Hudson River, including the astonishing Lined Seahorse.
Seahorses have captured the human imagination for thousands of years. With its horse-shaped head, little snout, and curling tail, a seahorse looks like a demure dragon or a tiny sea monster or an adorable mythical beast. Even its genus name, Hippocampus, is ancient Greek for “horse or sea monster.” This fish just looks magical or imaginary.
The River Project’s Seahorse Fact Sheet begins with this fact:
Seahorses are NOT unicorns.
The first thing to know about seahorses is that they are real.
The Seahorses of NYC
The Lined Seahorse (Hippocampus erectus), also known as the Northern Seahorse, is found in the brackish waters of New York Harbor and the Hudson River estuary. The seahorse adult is 3 to 6 inches long. Its color varies, though most seahorses in our murky waters are brown or gray. It may have lighter lines on its neck and tiny light spots on its tail.
The lined seahorse usually swims in a vertical position. It is a weak swimmer. It uses its long, prehensile tail to swim upright and to anchor itself to plant life at the bottom of the river.
The seahorse’s neck, body and tail are covered with rings of bony plates which help to protect it against predators. Its eyes can move independently of one another, so it can continually scan its surroundings.
The lined seahorse uses camouflage tactics like anchoring to a plant, staying still, and blending into the surroundings before ambushing its prey. It feeds on small crustaceans, fish eggs, and larvae by sucking them into its snout.
Nature’s Rarity: Male Pregnancy
The next time you are walking along the High Line or crossing the Brooklyn Bridge in the summertime, look out to the water and think, “Some male seahorse might be giving birth right now.”
As marine biologist Helen Scales describes in her wonderful book Poseidon’s Steed: The Story of Seahorses, from Myth to Reality, “The strangest thing about seahorses is that male seahorses are the only males in the world who have experienced — firsthand — the agonies of childbirth.”
A seahorse female places eggs in the male’s brood pouch. Only male seahorses, as Scales describes, “become truly pregnant, nurturing their young inside their bodies, providing them with food and oxygen whisking away waste products. This is all the more remarkable when we consider that pregnancy is a rare occurrence in fish, even among females.”
After three weeks gestation, the male goes into labor that can last from a few minutes to a few days. He gives birth to hundreds of flea-sized miniature seahorses. Then the female returns and the male may be pregnant again the very next day.
In the summertime, seahorses live in eelgrass, grass beds, and in the shallow waters around piers and beneath bridges. They’ve been spotted underneath the Brooklyn Bridge, near the shore of Staten Island, and all the way north to the Tappen Zee Bridge. They move to deeper waters in winter.
There aren’t any definitive numbers of seahorse populations in NY Harbor and the Hudson River. Their presence indicates the water quality and health of our waterways. But they are listed as vulnerable since 1996. Not only have they lost their habitat to pollution and coastal development, lined seahorses are also a popular for the aquarium trade and Chinese medicine.
I’d say the best way to spot a lined seahorse is to visit the River Project. What do you think? Have you seen a seahorse near NYC?