They were the aquatic beauties of the Northern California coast: ochre sea stars in jewel-bright colors, web-winged bat stars and the spectacular sunflower sea star that reigned as the Beyoncé of the breed. Bigger, brighter, bolder and hungrier than other species, these voracious prowlers could unfurl as many as two dozen arms, rocket across the ocean floor and devour a purple sea urchin in a blink. As an apex predator, the Pycnopodia helianthoides–sometimes dubbed the Death Star—feared none and was feared by all.
In 2013 a grotesque plague struck twenty sea star species from Mexico to Alaska. White lesions festered between their arms. Contorting into odd shapes, appendages broke off and crawled away. In just a few days a stricken sea star would dissolve into goo—“like the Wicked Witch melting in The Wizard of Oz,” as one diver described it.
Marine detectives scrambled to identify the culprit. Could it be a bacterium? A virus? A toxin? Warming waters? A combination of factors? After myriad theories and tests, a definitive answer remains elusive.
By 2017 Sea Star Wasting Syndrome had killed 90 percent of West Coast stars overall and an even higher percentage of sunflowers. The die-off of more than 5.75 billion of these “cheetahs of the sea” had catastrophic effects on the delicately balanced ecosystem. Without their primary predators, purple sea urchins multiplied into legions that grazed once-lush kelp forests into lifeless urchin barrens.
In 2021, after a COVID-induced hiatus, I waded into the Pacific for training as a tidepool docent with the Stewards of the Coast and Redwoods—and heard whoops of joy. “They’re back!” our leader exclaimed, pointing to iridescent ochre sea stars gleaming on the rocks. “We’re seeing evolution happening right before our eyes.”
Indeed we were. Somehow, perhaps by a genetic mutation, nature had found a way to produce a new generation resistant to or capable of recovering from wasting disease. Eventually bat stars also re-appeared, but sunflowers remained “locally extinct” in Northern California—until now.
This summer divers from the California Academy of Sciences spotted a young sunflower sea star in a cave on the Mendocino coast. “This little individual gives us a lot of hope,” one observed, “because if there’s one, there’s got to be more.”
Cutting-edge breeding programs, initiated in 2019 at the University of Washington Friday Harbor Marine Laboratories with support from the Nature Conservancy, aim to introduce many, many more. Through painstaking experimentation, researchers have succeeded at a never-before-done feat: spawning and raising sunflower stars in settings that mimic the natural environment. A growing number of institutions, including Moss Landing Marine Laboratoriy, Birch Aquarium at Scripps Institution of Oceanography at UC San Diego and the Aquarium of the Pacific, have launched similar programs.
The long-term goal is to place thousands of sunflower stars in the ocean, where they could help restore the kelp forests by keeping purple sea urchins in check. But can lab-bred sunflowers survive in the wild?
This is the question researchers at the Friday Harbor Lab are working to answer. In August they released ten pioneer sunflower stars into local waters, where they are monitoring their movements, growth, adaptability, survival rates and environmental impact.
“We’re not going to repopulate the entire ocean with these ten sea stars or even with the hundreds that we have in the lab,” lead researcher Jason Hodin told a reporter, “but we can show how it’s done.”
They also are offering hope to all of us who wish, not on stars, but for stars to glow once again under the sea.
