California’s northern and central coast has recently been devastated by unprecedented declines in kelp forest ecosystems. Off the northern coast, 90% of the bull kelp (Nereocystis luetkeana) has been lost since 2014. California’s central and south coasts have also seen declines in their native giant kelp (Macrocystis pyrifera). Kelp forest deterioration has also been observed further up the West Coast into Oregon and Washington, and even across the globe in Australia and New Zealand.
Research suggests that the recent kelp loss was due to a “perfect storm” of factors, including persistent warm water temperature that killed off kelp, followed by explosions of purple sea urchins that feed on kelp and have prevented its recovery. A wasting disease in sea stars, which normally help control urchin populations, is another factor that may also have been influenced by the unusually warm water temperatures.
The question now is how to restore these iconic ecosystems, especially in the face of continued environmental change in the ocean. Six funded research projects address key questions for restoration, including how to deal with the urchin overgrowth, how to raise and outplant kelp to restore lost ecosystems, identifying and cultivating resilient strains of kelp, and the creation of a spore bank to preserve genetic material.
Working closely with local and state resource managers, including the California Ocean Protection Council and California Department of Fish and Wildlife, the Kelp Recovery Research Program projects will directly inform the efforts of resource managers to protect and restore kelp ecosystems statewide.
KELP ENHANCED STATUS REPORT
California Sea Grant Extension Fellow Dr. Gina Contolini worked closely with the California Department of Fish and Wildlife to develop the Giant Kelp and Bull Kelp Enhanced Status Report, released in December 2021, that will help inform the state’s kelp restoration and management efforts.
Kelp Recovery Research Program PROJECTS
- Conservation genomics and gametophyte banking of bull kelp in California
Filipe Alberto (University of Wisconsin – Milwaukee), Peter Raimondi (UC Santa Cruz), Sergey Nuzhdin (USC)
Project Number: R/HCEOPC-14
- Where, when and how? A guide to kelp restoration in California using spatio-temporal models of kelp dynamics
WHERE, WHEN AND HOW? A GUIDE TO KELP RESTORATION IN CALIFORNIA USING SPATIO-TEMPORAL MODELS OF KELP DYNAMICS
Jennifer Caselle (UCSB), Tom Bell (UCSB), Mark Carr (UC Santa Cruz)
Project Number: R/HCEOPC-18
- A multi-pronged approach to kelp recovery along California’s north coast
Brian Gaylord, Marissa Baskett, Aurora Ricart (UC Davis), Matt Edwards (San Diego State University), Mackenzie Zippay, Brent Hughes, Sean Place (Sonoma State University), Jason Hodin (University of Washington)
Project Number: R/HCE-15
- Assessment of practical methods for re-establishment of northern California bull kelp populations at an ecologically relevant scale
ASSESSMENT OF PRACTICAL METHODS FOR RE-ESTABLISHMENT OF NORTHERN CALIFORNIA BULL KELP POPULATIONS AT AN ECOLOGICALLY RELEVANT SCALE
Michael Graham, Scott Hamilton (San Jose State University - Moss Landing Marine Laboratories)
Project Number: R/HCEOPC-13
- Informing restoration and recovery of central coast kelp forests – understanding the dynamics of urchin recruitment, reproduction, and density
INFORMING RESTORATION AND RECOVERY OF CENTRAL COAST KELP FORESTS – UNDERSTANDING THE DYNAMICS OF URCHIN RECRUITMENT, REPRODUCTION, AND DENSITY
Alison Haupt (CSU Monterey Bay), Jan Freiwald (Reef Check California)
Project Number: R/HCE-16
- Scaling a new cost-effective intervention tool to restore and future-proof coastal kelp forests
Joleah Lamb, Matthew Bracken (UC Irvine)
Project Number: R/HCE-17