Restoration

Helping the Kelp!

The extreme loss of bull kelp from historic beds along the Northern California Coast, as well as in Oregon, Puget Sound, and the Salish Sea waters, has made helping its recovery an urgent mission for scientists, Tribes, and communities alike. Kelp forests globally have been recognized as crucial for ocean biodiversity and health, and their decline in as far-flung places as southern Australia, coastal Portugal, or northern Norway has inspired kelp restoration efforts worldwide. The Global Kelp Alliance is tracking these efforts project by project and is a fantastic resource. The techniques and methods for each kelp recovery project target an endemic kelp species and involve the combination of a unique ecological drama with a unique combination of stakeholder communities. The edge of the Northeast Pacific Ocean, however, where bull kelp, or Nereocystis leutkeana, grows, presents particular challenges to kelp recovery teams: the water is freezing, the ocean rough, with low-visibility, and it is scary (there are sharks, and the coastal access difficult). Limited diver availability and a timing and seasonality to this particular species make restoring bull kelp forests tricky. As an annual, large bull kelp sporophytes are only present for part of the year, and restoration out plantings need to coordinate with bull kelp’s natural growing cycles.

Because of these challenges, bull kelp restoration is a newer enterprise than the relatively successful giant kelp restoration efforts of Southern California led by the Bay Foundation. Bull kelp restoration and farming projects throughout its range are still in experimental phases and need time, funding, and people power to achieve the ambitious outcome it hopes for: refugial patches of bull kelp that can sustain themselves over the long term.

A Coordinated Choreography

Successful bull kelp restoration projects are a complex dance involving a suite of partners working together in a coordinated choreography. A project lead will marshall the partners involved, choose a site, and begin with the mundane but important application for permits. The process described below involves marine labs, underwater survey teams, fishers, tribal leads, scientific divers, kelp geneticists, and many creative scientific minds working together. Work must be timed to coordinate with the longer days of spring and summer, when bull kelp naturally begins its sprint from tiny to massive, and the diving conditions of the North Pacific allow our human participation. Fortunately, funders are recognizing the complexity of this group effort and funding multiple players on a given kelp restoration team.

The kelp restoration project lead will coordinate the collaborators and processes described below in unique ways suited to the environmental conditions in the location chosen for human intervention. Puget Sound’s kelp restoration projects do not entail urchin removal; urchin barrens are not an issue there, but kelp crabs are. In Northern California, reducing urchin densities is essential before other work can begin. Please refer to the Case Studies to see how these processes and players described below are choreographed together into specific bull kelp recovery projects. It is important to remember that the learning curve around bull kelp restoration is steep with a tremendous amount of experimentation, research, and knowledge sharing across regions as the urgency of these efforts grows stronger and the need to help this amazing organism recover in the face of rising ocean temperatures is recognized. Every project provides new data points.

Bull Kelp Recovery Process — An Overview

Site Selection and Permitting first asks: where to put kelp restoration efforts? A given cove or section of ocean could be chosen using sophisticated models using up-to-date satellite data combined with historical charts and surveys, or a specific Tribe might insist that a traditional kelp-bed fishing ground be chosen for kelp enhancement efforts. Both are viable ways to choose a bull kelp restoration site. Getting permits for the work through state agencies is often a grueling process. Each state has its own system but in California, for example, permits are required to collect wild bull kelp for their reproductive material (sori), and a separate permit is required to build a bull kelp cultivation broodstock (lab-generated soral material) from this wild-caught soral material. The state rules around Marine Protected Areas also add complexity into the procedures required for obtaining a permit.

Bull kelp’s genetic diversity and genetic resilience to warmer oceans is being vigorously researched and the findings integrated into practice as cultivation techniques advance. Experimentation by a group of graduate student innovators has now perfected ways to keep bull kelp growing in tanks, continually producing spores, so the supply of cultivated material for outplanting is available year-round and can be timed to take advantage of bull kelp’s natural life cycle. These labs create the green gravel, bricks, spore bags, pavers, pyramids, and twine inoculated with microscopic kelp ready for outplanting by the scientific, Tribal, or commercial farm divers.

Seaweed conferences are full of presentations on innovative work exploring new underwater applications for growing bull kelp: a ‘gametoglue’ that hardens when in contact with seawater, a gelatinous pod, much like what you use in a dishwasher, that can be thrown from a kayak or paddleboard dispersing spores or gametophytes once it dissolves, or a structural apparatus called an ARKEV with baby bull kelp sporophytes woven into its rope structure to grow unhindered by urchin and fouling. The experimentation and brainstorming continues!

Grazer Suppression Efforts take immense people power, and require permitting by the state, allowing urchin harvesting (take of urchins) or culling (smashing urchin in situ) from a given kelp restoration site. These efforts can be led by commercial urchin divers, or coordinators organizing SCUBA and snorkeling citizen-science volunteers trained to harvest or smash urchins. The restoration areas must be cleared down to 2 urchins per square meter so that any new kelp growth won’t be immediately chomped. Commercial urchin divers harvest the larger red urchin—and the green urchin as you move north into BC and Alaska—for market, but the smaller purple urchin found in Oregon and California have not been commercially viable. Their harvest from restoration sites leaves them in great vats looking to creative thinkers to find uses beyond the compost piles. One use, land-based urchin ranching for uni (the gonads favored as sushi), is discussed under Kelp Farming & Aquaculture.

Kelp Enhancement and Outplanting Design  are the key to helping wild bull kelp recover. Designing the experiment for a specific restoration site is the team lead’s major task and involves a raft of experienced scientific divers to implement. The most up-to-date technique is stringing inoculated (seeded) twine on larger rope, strung between supports, and buoyed off the bottom to avoid the urchin grazers (see diagram). This process has evolved from the kelp farmers in Maine and Alaska who use similar techniques of inoculated twine on larger rope arrays. But the difference between the commonly farmed kelps such as sugar kelp and bull kelp has required additional experimentation, taking years at a time to find the optimal approximation of bull kelp’s natural growth environment.  Many restoration sites now will implement two or three different kelp enhancements in one project site. Other kelp enhancement methods involve inoculating stones (green gravel) that can be set onto the ocean bottom, or wiping sporulated goo onto ceramic plates to be put out in dedicated sites. These have proved vulnerable to urchin grazing and less successful than the seeded twine. The ARKEV units below entwine small bull kelp sporophytes into the array and have been deployed at Albion Cove and Big River in Mendocino, CA.

Underwater Surveys are essential to monitor the restoration site over time. Reef Check has become the number one organization throughout California, Oregon, and Washington, training volunteer divers to collect the data that describes the biodiversity of the kelp forest before collapse, the change as kelp is lost to urchin barrens or other stressors, and then to carefully monitor throughout the restoration project period and afterward, to record if restoration efforts have persistent results.

There are other processes crucial to successful restoration work adjacent to the hands-on urchin removal, kelp cultivation, and in-water kelp enhancement:

Mapping and Assessment are important both in terms of site selection and in the ongoing monitoring of the kelp canopy of restoration sites and historic kelp beds. Satellites have been used to create kelp canopy spatial data from 1984 to the present, logging canopy kelps at a broad range. More localized hi-res drone imagery is used to record kelp beds at a high pixel resolution and in some places such as Puget Sound and the Salish Sea, Tribal and volunteer kayakers are measuring kelp beds physically, by paddling around them with GIS locators. Kelp maps of kelp bed abundance as remembered by Samish tribal elders have informed kelp research in the San Juan Islands. 1911 kelp maps by the Department of Agriculture in the US and British Admiralty charts in BC are sometimes used as baseline data.

Predator Reintroductions are discussed frequently as important efforts that will be essential for long-term maintenance of kelp forests once balance is regained. Top predators and especially redundancy at the top predator position adds resilience to most ecosystems both terrestrial and marine. In the bull kelp forests of Northern California and Oregon the lack of redundancy—i.e. the extirpation of the sea otter— was felt keenly when the sea star wasting disease decimated the second predator population in those areas, the sunflower sea star (Pycnopodia).

Community outreach, artmaking, art exhibits, and engagement are now recognized as key efforts for successful kelp restoration projects. Storytelling and outreach are crucial for educating the public and attracting funding. Generating baseline knowledge and sustained enthusiasm from adjacent and interested stakeholders and community members is essential for long-term success as kelp recovery efforts stretch into an indeterminate future. The power of science, art, and storytelling has been written about in articles, confirmed by a growing interest in kelp-related events, and a growing number of artists concerned with and inspired by bull kelp. Seaweed festivals and art exhibits have gained enormous popularity and are popping up in as diverse spots as Kodiak, Alaska, the North Coast of California (KelpFest!), and Encinada, Mexico. The direct result is that more people understand the urgency of helping the kelp! Interesting cross-disciplinary endeavors have marketable or educational potential; these include artmaking workshops using kelp and seaweed, as well as ceramic and textile applications for using urchin harvested from restoration sites. Inspiration abounds.

Read next: Aquaculture and Regional Case Studies