The decline of California’s kelp forests since the marine heat wave of 2013-17 has seen solely minor restoration regardless of heroic efforts at restoration carried out by scientists, fishermen, coastal tribes, volunteer divers and conservationists. Neither is the risk to kelp localized. Relatively the loss, just like the growth of mega-wildfires on land from Los Angeles to Siberia and from Canada to Australia is available in response to an ever-warming world the place 90% of the human-generated warmth from the burning of fossil fuels is absorbed by the ocean.
Kelp forests cowl some 2.8 million sq. miles, extra space than the Amazon rain forest, and generate some $500 billion a 12 months in worth. This contains edible marine species (together with many species of kelp itself), thickeners and emulsifiers utilized in ice cream and cosmetics, and highly effective storm and coastal erosion safety, in line with a 2023 report in Nature Communications. Photosynthesizing kelp, a type of algae, additionally generates extra oxygen (and sequesters extra carbon dioxide) than does the Amazon basin. Together with coral reefs they represent one of the crucial complicated and productive — if little-known — ecosystems on the planet.
Kelp forests are a difficult cold-water realm, however for these of us who dive into these marine forests in locations like Monterey in Northern California or Catalina off L.A., they’re an entrancing cathedral of sunshine and life. Right here you’ll discover orange garibaldi (like goldfish on steroids), wolf eels, leopard sharks, curious harbor seals and multicolored marine snails often called nudibranch. They’re vibrant, entangling and light-shifting habitats of marvel and warning in our quickly altering seas.
Traditionally, overfishing, lack of predators like sea otters, air pollution and overharvesting have posed the primary risk to kelp forests. In the present day, it’s marine warmth waves. A 2026 examine carried out by scientists from the Nationwide Oceanic and Atmospheric Administration and 30 different establishments around the globe stories the ocean absorbed extra warmth in 2025 than ever earlier than. This in flip has set off a document variety of marine warmth waves that may improve regional water temperatures 5-10 levels, sufficient to radically alter ocean situations.
Due to this warming, these giant macroalgae are dealing with the largest risk to their existence since they developed greater than 32 million years in the past. In the event that they disappear, what occurs to the salmon, cod, abalone, whales and greater than 1,000 different creatures depending on kelp forests? What occurs to us? Neither science nor society has figured that one out.
Quite a few coastal communities have been hammered by the loss, similar to Fort Bragg, Calif., which has misplaced 95% of its kelp forest. The closure of leisure abalone diving alone (abalone feeds on kelp or starves to loss of life in its absence) is estimated to have price the world $25 million a 12 months. Tasmania, Australia, Norway, Mexico and southern Maine have seen comparable kelp lack of 80% or extra.
The hopeful information is that kelp is among the most resilient and fastest-growing organisms on earth — the bamboo of the ocean — able to rising as much as 2 ft a day, even because it faces speedy decline. I’ve swum via a kelp forest in a website that 10 years earlier was a moonscape-like sea urchin barren. One California cove stuffed with kelp was worn out by a landslide however totally recovered inside two years.
I’ve gone out with the nonprofit Bay Basis off Southern California, the place divers culled overgrown populations of urchins off Palos Verdes until there have been fewer than two urchins per sq. meter. The group was then in a position to see 80 acres of wholesome large kelp forest restored largely via pure spore dispersion. I’ve additionally gone diving with volunteers in Northern California the place comparable efforts are producing modest restoration in a number of rugged coves.
Within the Azores, Chile and Argentina, citizen motion has led to the creation of huge marine parks that defend wild kelp, whereas in South Korea, whose fisheries company invests $29 million a 12 months in restoring wild kelp for meals safety, restoration efforts have introduced again 50,000 acres of marine forest up to now.
And but, wanting a speedy transition off fossil fuels, which isn’t taking place at the moment, you actually can’t speak about hope for the way forward for kelp however as an alternative could must give attention to triage, saving what’s left, with the understanding that kelp forests, though resilient, are actually in want of energetic human intervention.
This might embody investing in important analysis, as proposed “Help Our Kelp” legislation in Congress has sought to do. Different interventions may embody restoring broken habitat to make sure that these wondrous underwater forests live on, increase the place potential and maybe sometime thrive once more, to the advantage of coastal communities each human and wild throughout the temperate seas of our still-awesome blue-marble planet.
David Helvarg is the chief director of Blue Frontier, an ocean coverage group, and co-host of “Rising Tide: The Ocean Podcast.” He’s the creator of the forthcoming “Forest of the Sea: The Exceptional Life and Imperiled Way forward for Kelp.”
