What Is Kelp?

Discover what we know about the ocean's biggest, yet often misunderstood, ecosystem

Weedy SeadragonOriginal Source: John Turnbull

What is Kelp?

Kelp forests are made of brown seaweed which produce thriving underwater cities filled with animals from the smallest snail to the largest whale. There is still a lot to learn about these habitats but here is what we do know...

Ecklonia close up in KoreaOriginal Source: Aaron Eger

1. Kelp is not a plant

Kelp is a bit different to your everyday land dwelling "plant". While kelp forests also harness the power of the sun to grow, produce oxygen, and capture carbon dioxide (CO2), they have no relation to the plants we are familiar with on land.

Kelp washed ashore on a sandy beachKelp Forest Alliance

Besides living underwater, kelp forests have many differences to land plants. They have no roots and instead capture vital nutrients from the water via any part of their tissue. What look like roots are actually "holdfasts" - structures that help stop the kelp from washing away.

Distribution of the world's kelp forestsOriginal Source: GRID-Arendal

2. Kelp is the biggest marine habitat on the planet

Kelp forests cover over 1/3 of our world's coastlines and cover more area than coral reefs, seagrasses, or mangroves.

Kelp community plantingOriginal Source: Jack Brookes

Over 750 million people live within 50 km of a kelp forest. If you are from London, LA, Sydney, Tokyo, NYC, Cape Town, Seoul, or Santiago, you even have a kelp forest in your blue backyard. Many people are connected to kelp without even knowing it!

Macrocystis in PatagoniaOriginal Source: Enric Sala

3. They're the second fastest growing organisms on earth

Giant kelp forests can grow around 4 meters (13 ft) in a single week - that's almost the height of 3 adults!

Bull kelp forest with pipefishOriginal Source: Ondine Pontier

This incredible growth means you could be snorkeling in a kelp forest, come back the next day, and the swaying branches have grown by the length of your arm!

BC kelp forest and rockfishOriginal Source: Alex Mustard

4. Kelp forests put dinner on your plate

Kelp forests support a dizzying array of sustainable seafood options around the world, including many of your favorites - fish, lobster, and abalone.

Sea urchin barrenOriginal Source: Ralph Pace

Kelps need balance

We must always make sure that we leave enough top predators in a kelp forest. Otherwise, there is no one left to eat the things that eat kelp. The results are devastating as a bountiful kelp forest can be transformed to an underwater desert.

By Bill EppridgeLIFE Photo Collection

5. Kelp forests have won an Oscar

Kelp forests are the best supporting' backdrop of the Academy Award winning documentary "My Octopus Teacher". The movie was filmed at a remote dive location in False Bay, near Cape Town, in the Western Cape of South Africa.

Six-gill shark in a South African kelp forestKelp Forest Alliance

Not only is South Africa home to the 'Big Five' safari animals, the Great African Seaforest is made of kelp forests that boast six-gill sharks, sea lions, and some of the most beautiful dive spots in the world.

Crayweed PlantingOriginal Source: Tom Burd

6. You too can help save kelp

Whether you're a scientist, business leader, government representative, artist, teacher, or just love kelp, you can #HelpTheKelp! Find out how to get involved at the Kelp Forest Alliance.

Credits: All media
The story featured may in some cases have been created by an independent third party and may not always represent the views of the institutions, listed below, who have supplied the content.
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