ocean plants

Endangered Ocean Plants Essential to Our Ecosystems

Jane Marsh - May 17, 2018

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When you think of the ocean, and especially endangered species in the ocean, what comes to mind? For most people, it’s things like adorable penguins, majestic whales or playful dolphins. While these animals are all important parts of their respective ecosystems and may be endangered, they’re not the only life forms at risk. Ocean plants are an essential part of our ecosystems, and many of them are endangered as well, thanks to overfishing and other human interventions. Here are a few ocean plants that are essential parts of their own ecosystem and part of the oceanic biosphere as a whole.

5 Endangered Plants in the Ocean

Gracilaria Skottsbergii

The Galapagos Islands are known for their remoteness — and if we’re being honest, for their massive, ancient turtles. It is, or was, also home to a very rare type of red algae known as Gracilaria Skottsbergii. First discovered in 1934 at depths between 12 and 27 meters, this algae is a primary food source for sea urchins and other herbivores in the area.

This is one of the few ocean plant species that is considered to be critically endangered. It is so rare at this point that it is nearly impossible to observe in the wild and may actually be extinct in some areas. Climate change is being blamed for the loss of this rare red algae, as changing ocean temperatures disrupted its ecosystem.

Johson’s Seagrass

Florida is known for its beaches and tourist attractions — and for Johson’s Seagrass, an endangered type of ocean plant that is only found in the waters around the Sunshine State. It is an integral part of the ecosystem, absorbing carbon dioxide from the water and acting as a food source for everything from green sea turtles to manatees. It also acts as a home to many of the native fish and shellfish that inhabit the waters around the state.

This particular seagrass is threatened by pollution and runoff from the state’s industrial and agricultural areas.  It is also damaged frequently by boaters passing on the water above them. As a slow growing seagrass, it doesn’t repair damaged areas quickly, making it difficult for this species to thrive when it is so threatened.

The Great Barrier Reef

While the reef itself isn’t a plant, the great coral structure is home to hundreds of species of plants and animals that will all be threatened if the reef dies. The obituaries for the reef that made the rounds on social media last year were more accurate than even their authors realized — the great reef is dying, because of climate change and human-introduced pollutants in the water.

When the Great Barrier Reef, this 25-million-year-old wonder of the natural world, finally dies, it will take its entire ecosystem with it. The ecosystem will collapse and all of the plants and animals that call the coral home will have to relocate or die — and most will probably die.


No, we’re not talking about the one-eyed villain from the Spongebob Squarepants cartoon. Plankton, the often microscopic plants that float throughout the oceans, are an integral part of nearly every oceanic ecosystem in world. They are being threatened by climate change and water pollution throughout the world — and if they die, life on Earth might go with them.

Professor David Thomas, of the University of Bangor, explained it best. “Half of the world’s oxygen is produced by these organisms. If you took that away you would lose the basis of life on the globe. There simply wouldn’t be enough oxygen to support life.” We, quite literally, can’t exist without plankton and many of the individual species are starting to become endangered due to human intervention.

Asian Surfgrass

The coasts of China, Japan and Korea are often heavily fished to sustain the growing populations of those three countries. One species that is taking the brunt of the damage causing by overfishing and aquaculture isn’t a fish at all — it’s Asian Surfgrass. This ocean plant used to grow all along the coasts of all three countries, serving as a food source for a variety of different animals.

Today, thanks to the growing kelp aquaculture industry in the area, this surf grass is dying out and can only be found in very limited areas in the region. Japan’s habit of using dynamite in fishing also damages the grass’ ecosystem, making it hard for it to grow back in damaged areas. It is currently listed as endangered, but the aquaculture industry might mean that this ocean plant isn’t too far from extinction.

Eyelash Seaweed

This ocean plant might sound a little strange, but it is one of the oldest plants in the ocean — at least that we’ve discovered so far. It is only found in one place — off the eastern coast of New Zealand’s South Island. Not much is known about this particular species of seaweed, in spite of its apparent age. It was only discovered in 2000.It is entirely possible that this species is extinct. The 2016 Kaikoura earthquake that rocked New Zealand lifted the seabed in the area where the eyelash seaweed is was discovered, and it hasn’t been spotted since. While this particular extinction might not directly be due to human actions, the fact that it was only found one some boulders off the coast of New Zealand might be due to the fact that it can’t spread further because of changing water temperatures or ocean chemistry.

Conservationists in the area are currently searching for any remaining eyelash seaweed populations so they can be studied further. All of these endangered ocean plants have two things in common — each one is an integral part of its local ecosystem, and each one is threatened because of climate change, agriculture and aquaculture, or other human interventions. Without ocean plants, the ocean’s ecosystem would collapse and we would lose an important source of food, medicine and oxygen that is essential for our continued survival on this planet. The plants can’t speak for themselves, so it’s up to us to protect them to ensure that the beautiful oceans that we enjoy today — complete with their majestic whales and playful dolphins — are there for future generations to enjoy.

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About the author

Jane Marsh

Starting from an early age, Jane Marsh loved all animals and became a budding environmentalist. Now, Jane works as the Editor-in-Chief of Environment.co where she covers topics related to climate policy, renewable energy, the food industry, and more.