The Vanishing Forest
From the rocky bluffs of Mendocino Headlands State Park, California’s North Coast appears almost postcard perfect: A salty breeze tempers the blazing sun, the sapphire sea crashes and swirls against the shoreline, and a golden retriever gallops toward the surf. BUT…beneath the waves, something is wrong.
Kelp forests as lush and impressive as the towering redwoods that grow farther inland once dominated these nearshore waters. A type of seaweed, kelp attaches to rocky surfaces on the ocean floor and, like trees and terrestrial plants, grows upward toward the sunlight. In fact, some experts call it “the sequoia of the sea.” It’s an appropriate nickname: Stems of bull kelp can soar more than 100 feet high, and its canopies—the frond-like blades that tangle on the ocean surface—are visible from space!
In temperate oceans across the globe, however, kelp forests are in decline because of warming waters, overharvesting and overgrazing by local predators, but they are on the verge of collapse in Northern California. There are only a few strongholds remaining. Through ongoing surveys using satellite, drone, and piloted aircraft imagery, scientists have found that in the past 10 years, 96% of kelp forests in the region have disappeared.
It’s an ecological disaster. From San Francisco to Oregon, nearly all that remains of one of the most productive ecosystems on Earth is an underwater wasteland. Hordes of native purple urchins are devouring kelp faster than it can reproduce. They eat the blades. They eat the stems. They even gnaw right through the plant’s base—causing it to detach from the sea floor, float away and die. And if any newly sprouting spores should appear, urchins will chomp them before they have a chance to grow.
It all began with a blob…
In 2013, a massive heat wave began to envelop the eastern Pacific, from Mexico to Alaska. Often referred to as “The Blob,” this warming event raised the ocean temperature by as much as 7 degrees Fahrenheit, triggering a slow cascade of underwater turmoil.
A mysterious disease broke out in the same stretch of the Pacific, annihilating the sunflower sea star, a voracious 13-pound invertebrate predator with more than 15,000 tubular feet but no brain, called “the scariest slow-motion monster you’ll ever meet,” by scientists. These unlikely hunters once ruled the reefs from Baja California to the Aleutian Archipelago, feasting on just about anything, but with a preference for sea urchins. With no natural predators remaining, purple sea urchins have devoured California’s kelp forests.
At the present time, scientists are working to accelerate the protection and restoration of kelp forests worldwide in an attempt to put the ecosystem back in balance. One factor in their favor… because kelp is one of the most productive and fastest-growing organisms on the planet—bull kelp can sprout up to 2 feet per day – scientists can understand in a relatively short window what successful growth looks like.
There’s a lot of hope around that.
