Kelp Research

California is facing a major crisis with the decline of its kelp forests. These underwater giants provide vital habitat for numerous species and support the state's economy through fisheries and recreation. A perfect storm of factors, including rising water temperatures and a surge in sea urchins, has led to a 95% loss of kelp along some stretches of the California coast.

To address this issue, in 2020, California Sea Grant, along with the California Ocean Protection Council (OPC) in coordination with California Department of Fish and Wildlife (CDFW), funded six projects totaling $2.1 million. These projects addressed the recent devastation to kelp forests along the northern and central California coast. 

Now, five new research and restoration projects, totaling over $5.8 million, launched in 2024 to focus on crucial questions for kelp recovery. Researchers will investigate optimal conditions for kelp growth, resilience to warming waters, and ways to empower California Native American tribes in restoration efforts.This new initiative represents a significant step forward. It combines scientific research with community involvement to develop practical solutions for restoring California's kelp forests.

The research programs also prioritize inclusion by supporting the participation of underrepresented students in marine science. With a focus on both immediate action and long-term planning, the collaborative effort offers a promising path towards restoring these vital underwater ecosystems.

 

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.

Read the Report

 

2024 Accelerating Kelp Research and Restoration in California Projects

A Proactive Approach to Kelp Restoration in CA: Forecasting Kelp Loss and Optimal Kelp Restoration Times

Project Lead: Jennifer Caselle (University of California, Santa Barbara)

Co-PIs: Anita Giraldo Ospina (University of California, Santa Barbara), Thomas Bell III (Woods Hole Oceanographic Institution)

Summary: Current efforts to restore kelp can only succeed if we understand the conditions kelps need to thrive. This project will create a forecasting tool for understanding future states of California’s kelp forests and to enable timely decision-making for kelp restoration. It also aims to identify monthly and seasonal factors in the environment that help or hinder kelp restoration. The project will develop tools that forecast the best timing and location for kelp restoration  — similar to the rainfall and temperature forecasting tools that farmers use to make strategic decisions about planting and harvesting crops.

Visit the project page here.

Evaluating a Novel Kelp Restoration Approach and the Conditions Conducive for Kelp Recovery and Restoration

Project Lead: Mark Carr (University of California, Santa Cruz)

Co-PIs: Sean Craig (Cal Poly Humboldt Sponsored Programs Foundation), Rietta Hohman (Greater Farallones Association), Brent Hughes (Sonoma State University), Joshua Smith (Monterey Bay Aquarium)

Summary: This project will conduct two studies to evaluate a novel approach to restoring kelp communities and to identify the best environmental and ecological conditions for kelp restoration. In the first study, commercial and recreational divers will clear kelp grazers, such as red and purple urchins and the wavy turban snail, separately and in combination, along the perimeter of remnant kelp forests and study how this might help kelp forests recover and expand. This study will also evaluate how often such clearing efforts will need to be repeated and at what financial cost and diver effort. The second study will investigate the range of  water temperatures, locations and methods that are best suited to ensure restoration success — for example, if it is more effective to outplant new kelp or remove kelp grazers so existing kelp can proliferate.

Visit the project page here.

Ghvtlh-k'vsh shu'-srnelh-'i~ (Kelp Guardians)

Project Lead: Rosa Laucci (Tolowa Dee-ni’ Nation)

Co-PIs: Cutcha Risling Baldy (Cal Poly Humboldt Sponsored Programs Foundation), Jan Freiwald (Reef Check Foundation), Torre Poizzi (Sunken Seaweed LLC), Morgan V. Murphy-Cannella (Reef Check Foundation)

Summary: The recent decline of California’s ghvtlh-k’vsh (kelp) forests directly affects the cultural lifeways and thus health of the Tolowa Dee-ni' Nation. This project will train and certify up to ten Natural Resources Staff and Tribal Citizens of the Tolowa Dee-ni' Nation to conduct both kelp monitoring and restoration efforts, including establishing kelp nurseries and grow-out sites. These practices may serve as a template for other Indigenous tribes or organizations that want to develop kelp forest monitoring and restoration within their ancestral territories.

Visit the project page here.

Accelerating Bull Kelp Ecosystem Recovery in a Recently Deforested Location in Northern California by Using a Strategic Sequence of Restoration Techniques & Community Participation

Project Lead: Tristin Anoush McHugh (The Nature Conservancy)

Co-PIs: Benjamin Grime (The Nature Conservancy), Joshua Smith (Monterey Bay Aquarium), Grant Downie (California Sea Urchin Commission and Commercial Urchin Harvester), Michael Springborn (University of California, Davis), Jan Freiwald (Reef Check Foundation), Marianna Leuschel (New Agency), Brent Hughes (Sonoma State University), Scott Hamilton (San Jose State University - Moss Landing Marine Laboratories)

Summary: This project aims to recover five acres of recently degraded bull kelp forest at Big River, Mendocino County, by deploying a strategic combination of kelp recovery solutions and providing community participation opportunities. The project will bring together thinkers from twelve organizations in a coordinated, interdisciplinary effort to truly scale and accelerate kelp recovery.

Visit the project page here.

Thermal Tolerance, Population Variability and Experimental Restoration in Kelp in Southern CA

Project Lead: Jennifer Smith (UCSD/Scripps Institution of Oceanography)

Co-PIs: Siobhan Braybrook (University of California, Los Angeles), Todd Michael (The Salk Institute for Biological Studies), Jules Jackson (Coastal Defenders), Mohammad Sedarat (Scripps Institution of Oceanography)

Summary: The persistence of California’s kelp forests continue to be threatened by rising ocean temperatures and more frequent and intense marine heat waves, particularly in southern California where kelps experience some of the highest temperatures in their geographic distribution. This project will investigate variability in the thermal tolerance of six kelp species and the role that genetics plays in this. It will establish a seed bank and test how kelp survival and growth once outplanted relates to thermal tolerance.   

Visit project page here.

 

2020 Kelp Recovery Research Program PROJECTS & Final REPORTS

Conservation genomics and gametophyte banking of bull kelp in California

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

Final Report: Linked here

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

Final Report: Linked here

A multi-pronged approach to kelp recovery along California’s north coast

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

Final Report: Linked here

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

Final Report: Linked here

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

Final Report: Linked here

Scaling a new cost-effective intervention tool to restore and future-proof coastal kelp forests

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

Final Report: Linked here

News Feature: Cutting-edge Science for Kelp Restoration

Results from six innovative research projects will help protect and restore California's vital kelp forests. Read the news story here.

 

ADDITIONAL KELP RESOURCES

StoryMap: How Scientists Are Working to Restore California's Kelp Forests

Ocean Protection Council Kelp Action Plan

Kelpwatch

Greater Farallones Association Kelp Restoration

California Department of Fish and Wildlife Kelp and Other Marine Algae page

Santa Barbara Coastal Long-term Ecological Research satellite remotely-sensed kelp canopy area dataset