Protecting the Unicorns Beneath the Sea: The Secret Seahorse Colony of Long Beach

A Pacific seahorse in a red gorgonian sea fan. Getty Images.

Every five days for the past three years, Rog Hanson has driven two hours in the middle of the night to visit his colony of four Pacific seahorses, dubbed Bathsheba, Deep Blue, Daphne, and CD Street. As Deborah Netburn reports at the Los Angeles Times, the colony’s location in the waters off Long Beach, California is a guarded secret. Together, he and fellow seahorse enthusiast Ashley Arnold have spent hours upon hours under the sea observing and documenting the colony’s behavior and sharing what they learn with scientists. For him, it’s a calling he was drawn to after a close, very personal encounter with a whale; for her, diving is a way to do good and help manage the PTSD she has as a result of her military service.

If you get Hanson talking about his seahorses, he’ll tell you exactly how many times he’s seen them (997), who is dating whom, and describe their personalities with intimate familiarity. Bathsheba is stoic, Daphne a runner. Deep Blue is chill.

Hanson makes careful notes after all his dives in a colorful handmade log book he stores in a three-ring binder. On this Wednesday he dutifully records the water temperature (62 degrees), the length of the dive (58 minutes), the greatest depth (15 feet) and visibility (3 feet), as well as the precise location of each seahorse. His notes also include phase of the moon, the tidal currents and the strength of the UV rays.

“Scientists will tell you that sunlight is an important statistic to keep down,” he says.

He has given each of his four seahorses a unique logo that he draws with markers in his log book. Bathsheba’s is a purple star outlined in red, Daphne’s is a brown striped star in a yellow circle.

Now, Arnold and her boyfriend, Jake Fitzgerald, check in on the seahorses about once a week and help Roger rebuild the city he created for them.

“We call them our kids because we love them so much,” Arnold says.

Hanson and Arnold are very protective of their seahorse family. They tell visitors to remove GPS tags from their photos. They swear them to secrecy.

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