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Posidonia Oceanica

In this video we talk about the Posidonia, why it’s so important and what can we do as sailors to protect it. I’m in Mallorca. A popular sailing destination! One reason this region attracts sailors is because of the crystal clear waters. We have to thank the Posidonia for that!

Recently a new law has been put into place here in the Balearics giving the Posidonia a higher state of protection.

What is Posidonia Oceanica?

Posidonia Oceanica is a seagrass, also called Neptune grass. Posidonia ONLY lives in the Mediterranean sea and is believed to be 10 thousands of years old. 3% of the Mediterranean is covered with Neptune grass.  In 1999 Posidonia fields in Ibiza and Formentera have been declared world heritage site by UNESCO! There’s a reason the seagrass has been named after the Greek god of the seas.

Why is Posidonia important?

Four reasons why the Posidonia is important:

  1. For lots of fish, sea animals and plants, the Posidonia is their shelter place and home, their shelter, and nutrition.
  2. Posidonia purifies the water and helps to clean up the sea. It makes the water crystal clear, the sand super fine, and it gives the Balearics one of the most beautiful beaches in the world.
  3. Plays an important role against the eroding of beaches and dunes. / Produces some of the sediments you can find on the sand and, during the winter protects the beach by preventing loss of sand.
  4. They are the lungs of the sea, absorb big amounts of CO2 and provide the oxygen we breathe. Did you know that for more than 50 % of our breaths we’re dependent on the ocean? One hectare oPosidoniaia produces 100.000 liters of oxygen per day. This is 5 times more oxygen than a hectare in the Amazone rainforest. It also absorbs 3 x as much co2 as the rainforests. This makes the Posidonia of essential importance against climate change!

The Posidonia Challenges

More Posidonia is disappearing then is growing. Posidonia Oceanica is red-listed by the IUCN. It’s a very slow growing species. The seagrass only grows about 2 cm per year. It’s getting more and more damaged, mainly by pollution. Plastics, Chemicals from agricultural run-off, sunscreens, shampoos and soaps we use, sewage, and desalination plants, diminishes the amount of light available to the plants. And light it needs to grow. Also, the cumulative effect of boat anchors and shaving chains are killing and damaging the Posidonia. Anchors pull out the roots of the Posidonia. You can compare this with pulling out a tree in the Amazon. Creations of nature that took dozens of years to grow.

With more tourists, more boats, more pollution, a changing climate and an acidifying sea we are putting more pressure on the ancient plant. It is slowly it’s disappearing, and with it, all the benefits that brings.

We have to thank the Posidonia for the crystal clear waters and the quality of our air. What can we do, as sailors, so the Posidonia also thanks us?

What can we do as sailors to protect the Posidonia?

Plan for mooring and anchoring

  • Opt for places where they have installed Buoys.
  • If it’s essential to use an anchor, make sure to choose an area free of Posidonia. Check charts, satellite images, and user-generated info on navigation systems to identify white sand areas and contours, a Posidonia free area. There are some sweet apps, tools, and resources out there that can help you identify moorings, safe zones.
  • Some areas have Posidonia control boats you can call on the radio to help you find an appropriate anchor spot. Check the pilots and local information to find out.
  • Arrive in the day so you can see where the white sandy parts are to anchor. Both the Anchor and the chain should be in sand.

Posidonia sailing resources in Spain

Here you can reserve buoys in advance in the Balearics.

Posidonia Maps Balearics

Save Posidonia App Ibiza & Formentera

Posidonia Maps (App)

Other Posidonia action tools and tips:

Contribute Posidonia free anchorages to sailing apps like ActiveCaptain

What can we all do to protect Posidonia Oceanica?

    • Be conscious of the actions you take. Use Ocean Friendly Soap & Shampoo, Ocean Friendly Sunscreen, and cleaning products. Discharge black water offshore or with marina services. Find more #PlasticFreeNomad Tips
    • Spread the word amongst sailors. Not everyone is aware of the importance of Posidonia! Awareness is the key to action. Share this blog and the video to make other aware of the Posidonia.  
    • Last but not least. Dive in to see for yourself how beautiful this seagrass is and how much life hides in it.


Decret sobre la conservació de la Posidonia oceanic

Save Posidonia Project Formentera 2017

The seagrass Posidonia oceanica: Ecosystem services identification and economic evaluation of goods and benefits

About Ocean Nomad TV

Ocean Nomad TV brings you the best of  Ocean Nomad Life, my (hitch)sail adventures, ocean explorations and discoveries, and the journey from a total newbie in sailing to building a boat. With 5-20 minute videos, I aim to encourage, inspire for ocean adventure travel and saving our seas.

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Hi! My name is Suzanne. I'm here to help you go on ocean adventures and make positive impact for a healthier ocean. Explore this website to learn what I do and how you can make some splashes too!

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