The kelp forests of central California, and particularly those within Monterey Bay National Marine Sanctuary, have undergone interesting and, in some cases, dramatic changes in the past decade. Since a series of marine heatwaves warmed coastal waters beginning in 2014, iconic kelp forests — once a common sight — have changed in a variety of ways: some kelp-dominated rocky reefs are now urchin-dominated; other areas are a mosaic of kelp and urchins; and some areas seem relatively unaffected.

The concurrent decline of kelp and the increase in visible purple urchins occurred at the same time that sea star wasting syndrome decimated 20 species of sea stars, converting the multi-armed predators into piles of goo. The sunflower star (Pycnopodia helianthoides), a beautifully colored species in bright orange, yellow or purple hues, was the largest and fastest of the local sea stars, and with its 20-plus rays (or “arms”), an active predator in kelp forests. Tim Herrlinger’s 1983 master’s thesis, “Moss Landing Marine Labs,” provided insight on the diet of sunflower stars. It indicated that the stomach contents of 41 individuals captured in Monterey Bay consisted mostly of gastropods (e.g., snails, 79%) and crustaceans (e.g., hermit crabs, 13%). Of the 353 different prey species found in the stomachs of sunflower stars by Herrlinger, only four were urchins.

Sunflower stars have been touted as key predators of urchins, and they do eat urchins. A recent lab study in Oregon demonstrated an adult sunflower star takes about a day to completely consume a single adult urchin, whereas lab-grown, juvenile sunflower stars in Washington consume multiple tiny (“Sunflower stars are amazing animals, and it is unfortunate that they are currently locally extinct in the sanctuary. They were never very common in central California, unlike Washington, Canada and Alaska, where they could carpet a reef, at least they did before the wasting syndrome,” said Lonhart. “And because sunflower stars in central California eat lots of different prey species, they may not solely focus on urchins, although the urchins will be hard to miss in some areas, and might be the only common prey item left!”

Currently the sunflower sea star is listed as critically endangered on the IUCN Red List of Threatened Species and is classified as threatened under the U.S. Endangered Species Act. The species may be formally listed as endangered in the next year, which would make the species the first sea star to be added to the U.S. Endangered Species List.

But help is on the way. The Sunflower Star Laboratory is a Monterey-based nonprofit committed to restoring sunflower star populations. This group is supporting research and developing aquaculture methods to restore sunflower stars to their historic range in California.

“Saving the critically endangered sunflower star is one important component of restoring ecosystem function to California’s kelp forests,” said Dr. Jan Freiwald, Sunflower Star Laboratory board member. “We are interested in advancing our knowledge of how sunflower star predator-prey interactions at various life stages occur across local environments.”

The Sunflower Star Laboratory focuses on sunflower star conservation and research, partnering with fellow members of the Pycnopodia Recovery Working Group to grow this critically endangered species at the Sunflower Star Laboratory Moss Landing aquaculture facility, coordinating sunflower star research amongst partners in California and beyond, and conducting outreach to our local communities. Readers can learn more about the Sunflower Star Laboratory work at sunflowerstarlab.org.

Superintendent Lisa Wooninck and her staff at NOAA’s Monterey Bay National Marine Sanctuary conduct research, education and resource protection in one of most biodiverse marine protected areas in the world. Learn about new and exciting stories by the sanctuary within these articles Lisa can be reached at lisa.wooninck@noaa.gov. To learn more about the sanctuary, visit montereybay.noaa.gov.