Transcript for Save Posidonia Oceanica Meadows

SAVE POSIDONIA OCEANICA MEADOWS TREASURY OF BIOLOGICAL DIVERSITY OF THE ADRIATIC SEA

This is the marine plant Posidonia oceanica.

It is also known as sea-grass.

Posidonia is not algae, but it is a superior marine plant with leaves, stalk and roots.

It is the endemic species of the Mediterranean Sea, because this is the only place where it can be found.

Posidonia grows on the sandy sea bottom up to about 50-metre depths,

where it forms thick submarine meadows.

Dark green leaves of Posidonia can grow up to over one metre of length,

and they can sometimes reach the very surface of the sea.

Posidonia flowers very rarely, every few years.

The olive-shaped fruit grows after the flowering.

More frequently, Posidonia breeds asexually, by rooting of the torn parts of the plant.

Posidonia plant grows very slowly, only one centimetre a year.

Some plants covered by sediment can be as many as a few metres long.

Such plant is a few hundreds years old, or even a thousand years.

Posidonia is the longest living organism of the Mediterranean Sea.

The community of the sea-grass is the richest community of the Mediterranean.

Posidonia meadows teem with life.

Inside the meadows, a few hundreds of plant and animal species live and breed.

In the waters above the meadow swim shoals of block-tailed sea breams, silvery grunt and small blue fish.

A bit lower, among the plants of this true sea forest, many other fishes will look for their food.

Sea bass (Serranus scriba) is a frequent inhabitant ofthe meadows,

and the bright red cardinal fish lives in small shoals in deeper and darker parts of the meadows.

Wrasse takes off its food - tiny snails, crabs and shells - from Posidonia leaves.

Many economically important species of fish, crabs and mollusks spawning,

hiding and living in the Posidonia meadows inhabit the surrounding maritime areas and enrich them.

Among the leaves of Posidonia, the male of the long- snouted wrasse also builds the nest

where the females lay their spawn.

Next to the border of the meadow is this group of purple sea-urchins,

with their bodies masked with shell and small stone fragments.

Octopus is a frequent inhabitant of the meadows.

It is awake at night as well, a very lively time in the meadows.

Just like tiny glow-worm, playful shoals of sea worms let out clouds of gametes in their love dance.

Large nude sea snail sails above the immense green meadows.

A delicate little house of this snail, which can be about 40 centimetres long,

is completely covered with its mantle.

When in danger, nude snail lets out a poisonous pink liquid

so as to defend himself when attacked by enemies.

Hundreds of algae and small immovable animals species overgrow Posidonia stalks and leaves.

All together, they build up the richest life community in both the Mediterranean and the Adriatic Sea.

Biological diversity - large number of plant and animal species inhabiting them -

is the reason why Posidonia meadows are so important.

The meadow is also the habitat ofour largest and legally protected shell the noble pen shell.

Along with the extraordinary biological diversity, Posidonia meadows have

other important and irreplaceable functions in the maritime eco-system.

Vast Posidonia meadows produce oxygen, which enriches the sea and the sea bottom.

Preserved and thick meadows are our submarine forests.

Through thick intertwined submarine stalks and roots, they strengthen the sediment

thus preventing its removal,

while their long leaves reduce the wave motion thus protecting the coast from erosion.

Posidonia leaves "imprison" various particles swimming in the sea-water,

which increases its transparency.

Posidonia meadows are extremely endangered and constantly reduced

under the influence of various man's activities.

As much as 40% of todays world population inhabits coastal areas

which is the reason why the pressure on the sea and the submarine areas is enormous

while the man increasingly destroys the submarine world with his activities.

Because of the importance of Posidonia, its sensitivity and the fact of its being endangered,

many Mediterranean countries have legally protected this species.

Despite the obvious signs of disappearance, of meadows in the Croatian submarine areas,

it is still not protected in Croatia.

There are countless man's activities endangering Posidonia!

Dredging and trawling over shallow coastal areas destroys vast surfaces of Posidonia.

Anchor is one of today's biggest enemies of Posidonia

because anchoring causes the pulling of the plants from the sediment, which damages the meadows.

Posidonia is also endangered because of aquaculture,

the increasingly developing artificial fish and mollusks farming.

ln the polluted areas, especially where sewage and various other waste waters are discharged,

large quantities of organic and inorganic substances enter the sea.

Posidonia meadows are thus covered and the sea transparency is reduced.

The meadow suffocates, leaving only the desert.

Because of its slow growth and breeding,

every damage of Posidonia meadows is considered almost irreparable.

We are witnesses of the ever more intense coastal construction,

The coast is being paved with concrete, embanked, numerous new marinas keep sprouting,

break-waters are being constructed along with the submarine infrastructure...

All these activities cause the decay and the disappearance of Posidonia meadows.

The situation of the Adriatic sea bottom is alarming.

Only a few decades ago, Posidonia used to be widely spread along the entire Istrian coast.

Today, the only remaining meadows can be found in the very south of Istria,

in the Li�njan sea, and here, on the Kamenjak Promontory.

Dark stains of Posidonia are spread like islands dispersed on the sea bottom

of this protected Istrian landscape.

The extinction of Posidonia meadows in Istria endangers

thousands of other plant and animal species living here.

The disappearance of meadows is the greatest loss of both ecological and

economic value of coastal eco-systems.

Thus, the protection of the last Posidonia meadows holds a great biological, economic, and cultural value,

and it should be a priority in the management of the sea and coastal resources.

Only the establishment of marine protected areas and proper attitudes of all those whose activities affect

Posidonia meadows, can preserve these last oases of rich marine life.

Be the ones who will protect our sea and the richness it gives us!

How can WE help?

Do not anchor in Posidonia meadows -anchors pull out plants

that are very often a few hundred years old, and together with them, many algae and immobile animals.

Fishermen: Do not trawl over Posidonia meadows! If we preserve Posidonia meadows we will protect

many fishes and crabs with big economic value. Your future depends on these rich marine habitats as well!

Coastal construction and aquaculture activities in the area

where the longest living Mediterranean organism Posidonia grows should not be allowed!

The environmental organization "Green Istria" started the campaign of rising

education and public awareness regarding the importance and the protection of Posidonia oceanica.

This campaign is a part of the long term project through which "Green Istria"

works on the establishment of Marine Protected Area

on the Kamenjak Promontory, on the Medulin archipelago and the Li�njan coastline.