Sunflower Sea Star
Pycnopodia helianthoides
Overview
Pycnopodia helianthoides, commonly known as the sunflower sea star, is a large sea star found in the northeastern Pacific Ocean. The only species of its genus, it is among the largest sea stars in the world, with a maximum arm span of 1 m (3.3 ft). Adult sunflower sea stars usually have 16 to 24 limbs.
They vary in color. Sunflower sea stars are predatory and carnivorous, feeding mostly on sea urchins, clams, sea snails, and other small invertebrates. Although the species was widely distributed throughout the northeast Pacific, its population rapidly declined from 2013.
The sunflower sea star is classified as Critically Endangered on the IUCN Red List.
The sunflower sea star has experienced catastrophic population declines of over 90% across its range since 2013, primarily due to sea star wasting syndrome, a devastating disease that causes tissue deterioration and death. Ocean warming and acidification have exacerbated the species' vulnerability to this pathogen, while also reducing prey availability and suitable habitat conditions. The rapid spread of the wasting disease has been linked to marine heatwaves and changing ocean chemistry, making recovery extremely challenging.
Habitat
Pycnopodia helianthoides inhabits rocky subtidal areas, kelp forests, and sandy bottoms from the intertidal zone to depths of 435 meters along the Pacific coast. The species prefers cool, nutrient-rich waters and is particularly associated with kelp forest ecosystems where it serves as a keystone predator.
Conservation measures underway
Threatened in Canada
Frequently asked questions
Why is Sunflower Sea Star classified as Critically Endangered?
Where does Sunflower Sea Star live?
What are the main threats to Sunflower Sea Star?
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