Sunflower Sea Star

• GeneralIt can have 24 arms and move at 1 m a minute; an epidemic has devastated it since 2013.
• It is one of the largest sea stars in the world: it reaches a metre from tip to tip, with between 16 and 24 arms and some 15,000 tube feet. And it is among the fastest: it covers up to 60 metres an hour.
• It begins life with five arms and adds more as it grows.
• Since 2013 it has suffered sea star wasting syndrome, the largest marine wildlife disease outbreak on record. The animals turn lethargic, develop lesions, lose their arms and disintegrate within days.
• The decline was 90.6 %, calculated from more than 32,000 surveys, and in 2020 the IUCN classified it as Critically Endangered.
• Its disappearance triggered a chain collapse: it feeds mainly on sea urchins — more than 90 % of the diet in some individuals — and without it purple sea urchins multiplied and stripped the kelp forests, turning them into urchin barrens.
• Captive breeding programmes are running in the Salish Sea, and refuge populations of large adults survive in some British Columbian fjords.

Skeleton type

Invertebrate - internal calcareous endoskeleton made of plates (ossicles)

Habitat & environment

Rocky bottoms and kelp forests

Sources consulted: https://es.wikipedia.org/wiki/Pycnopodia_helianthoides