Fish & Water - Sounds Wild
Sunflower Sea Star

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Sunflower sea star

The tide is out on a summer day in Southeast Alaska, exposing sea urchins and some large sea stars. But even bigger sea stars lurk a little further out in slightly deeper water. That sub-tidal zone is home to the Sunflower Sea Star, the swiftest, largest, and heaviest sea star in the Pacific, and perhaps the entire world. Fast-moving (for a sea star), these bottom dwelling predators can move five to ten feet in a minute, “outrunning” the sea urchins, snails, and sea cucumbers they prey on. Sunflower Sea Stars typically have 16 to 24 limbs and can be almost a meter across.

Between 2013 and 2017, an outbreak of sea star wasting disease killed millions of sea stars on the Pacific coast, including Sunflower Sea Stars, especially across the southern portions of its range. From Baja, Mexico, north to the outer coast of Washington, the once common Sunflower Sea Star virtually disappeared. Declines in B.C. and Alaska were less severe than those further south. The exact cause of the disease is unknown, but there is evidence that warmer temperatures played a role.

Biologists with the Alaska Fish and Game are monitoring sunflower sea stars to learn more about how their numbers in Alaska may change in coming years.