Ms Norah Eddy1, Ms Tristin McHugh
1The Nature Conservancy, United States
California’s iconic kelp forests are one of the defining features of the California coastline, and they are at risk of disappearing. Bull kelp (Nereocystis luetkeana) is the foundation species of the nearshore kelp forest ecosystem along California’s North Coast (Springer et al. 2010). Beginning in 2013, a marine heatwave triggered a number of stressors, including the die off of a sea star species and the subsequent outbreak of the purple sea urchin population. This led to unprecedented declines of over 96% of bull kelp canopy and habitat across much of the 350 km region (McHugh et al. 2018; Rogers-Bennett and Catton 2019; McPherson et al. 2021) resulting in devastating impacts on the ecological and human communities that depend on kelp. High densities of purple sea urchins remain across much of the region and continue to suppress kelp recovery in the region, though oceanographic conditions have since stabilized. A series of highly collaborative, science-driven restoration projects have been launched in the region since 2019 in order to create a network of bull kelp refugia to create habitat, preserve genetic diversity, and maintain spore sources to facilitate broader bull kelp recovery (Hohman et al. 2019). Here we will explore the specific tools — from urchin traps to commercial hand harvest, to in situ culling by recreational divers, to green gravel — and the scientific and collaborative approaches used in a suite of projects aimed at address kelp forest declines in the region.