Groundbreaking Settlement of Frozen Giant Pink Star Larvae Inspires Hope for Critically Endangered Sunflower Star Conservation
San Diego Zoo Wildlife Alliance, Sunflower Star Laboratory, Omaha’s Henry Doorly Zoo and Aquarium, Aquarium of the Pacific, and partners continue work to save sunflower stars from extinction.
Credit: Aquarium of the Pacific
June 17, 2025
MOSS LANDING, Calif., (June 17, 2025) – In a groundbreaking effort, a team of conservation partners froze, thawed, and settled larval giant pink stars (Pisaster brevispinus) into juveniles, the first time this process has been completed with a species of sea star. This success serves as a model for utilizing frozen larvae as a conservation tool for sea star recovery, including the critically endangered sunflower sea star (Pycnopodia helianthoides).
This first-of-its-kind achievement was the result of significant collaborative efforts from numerous partner institutions. Adult giant pink stars were spawned and their gametes cross-fertilized by scientists at the Aquarium of the Pacific, resulting in thousands of viable larvae. These larvae were cryopreserved in San Diego Zoo Wildlife Alliance’s Frozen Zoo® by the organization’s reproductive sciences team, with the assistance of protocols developed by partners at Omaha’s Henry Doorly Zoo and Aquarium. The frozen larvae were transferred to conservation nonprofit Sunflower Star Laboratory, where they were thawed, grown through their larval stage, and settled into juvenile sea stars.
