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Are We Witnessing the Loss of the Mediterranean Paradise?

Scientists talk on their collaboration for saving species from extinction

Interview with scientists Jose Tena (Director of the IMEDMAR-UCV), Jose Rafael Garcia March (Scientific Coordinator of IMEDMAR-UCV) Institute of Environment and Marine Sciences Research (University Catholic of Valencia. Both are professors of the Marine Sciences.

1. What is the project you are currently working on?

Reduction in biodiversity, translocation of species and alteration of natural habitat and community composition due to human action and climate change are causing the occurrence of infectious marine diseases, some of which produce mass mortalities with considerable ecosystemic and economic costs.

The Mediterranean Sea is considered as a laboratory to examine global processes.

Currently, we are implementing a project to save Pinna nobilis: a species of fan mussels that is endemic to the Mediterranean, but now endangered with extinction.

This species is mostly unknown for the general public, but Pinna nobilis was the second largest in size in the world and the largest in the Mediterranean (with a size up to 1 meter). The scientists work on reproducing the species.

At the end of 2016, we discovered that Pinna nobilis had been affected by a pandemic disease and that the species was in danger of extinction.

Later, in October 2017, having analysed all the available data, we understood that the mortality rate was 100%. The disease spread so rapidly that the Spanish government immediately agreed to grant a subvention to developing a project to rescue 215 individuals and try to save the species (project: Rescate de 215 ejemplares de nacra (Pinna nobilis) y su mantenimiento en 5 centros especializados en el marco del Proyecto UFE IP-PAF INTEMARES (LIFE15 IPE ES 012), "Gestión integrada, innovadora y participativa de la Red Natura 2000 en el medio marino español").

The species lives only in the Mediterranean Sea, so very quickly we received support from other countries of the Mediterranean basin, and a joint project of the scientists in Spain, Italy, Greece and France was prepared to save the species, under the call "Life" of the EU. The project is named LIFE Pinnarca and it has passed the first phase.

In February 2017, 16 adult fan mussels were collected from the “Marina Real de Valencia” in the Port of Valencia. Eight individuals were hosted at the IMEDMAR-UCV and the other 8 at the Oceanogràfic Aquarium of Valencia. Another 100 and 115 individuals were collected from the Alfacs Bay (Ebro Delta, Tarragona) and Port Lligat (Cap de Creus, Girona), respectively, in November 2017 and transported to indoor facilities. All rescued species were placed in 400 to 5.000-l tanks in groups of 4 to 12 individuals. All individuals were laid vertically with the anterior end of the shell pointing downwards, but unburied and without sediment. Various supports, such as concrete blocks where the individuals were inserted in holes, or PVC tubes where the individuals leaned on one side, were used to maintain the individuals in the vertical position. Individuals were also arranged to avoid the proximity of inhalant and exhalant chambers between contiguous specimens. To feed fan mussels, an initial daily mixture of phytoplankton gel (easyreefs®), autoclaved muddy detritus with high organic matter (OM) content and supplements (lyophilized easy SPS®) was supplied.

The institutions were taking care of rescued species for 2 years. Rescued individuals have provided valuable advances in the study of the disease,helping to prepare new tools for the quick identification of its presence in samples, to conduct breeding studies, and in general, to try to better understand the aetiology of disease and its global implications.

Through model simulations the scientists understood that water temperature and salinity seem to be related to the occurrence of the disease. These two factors are strongly influenced by climate change and anthropogenic actions. Now the scientists are looking for how to breed the species in captivity.

2. What is Pinna nobilis role for the ecosystem? For the sea?

Pinna nobilis have been known for many centuries; they were described by the Greeks... the byssus filaments of Pinna nobilis were considered seas-silk or sea-gold, and were used to make a very very expensive garments for the Romans. It is said that the cloth with the holy face of the Christ was made with these filaments.

Pinna nobilis performs a function of water cleaning. It needs water to live and it filters salted water to use it. It makes water cleaner. Also living in the sand, they are home for some animals and plants.

Further to its function, the case of Pinna nobilis demonstrates how climate change and human actions may influence the ecosystem, it poses several questions: are we witnessing the potential extinction of a sentinel species? Can we avoid it by applying active measures? If so, which measures will be more effective? How many other more overlooked species might experience a massive and unnoticed die-off before it is too late to implement any preservation action?

3. What is the current situation with Posidonia? Is it important for biodiversity?

We can see a lot of this species on the beach, making it very difficult to know that in reality Posidonia is in danger of extinction.

Posidonia is very important to the ecosystem.

It creates an environment that protects juveniles of many species, many of them of fishing importance. It fixes the sediment, captures a great amount of CO2, one of the main gases producing the greenhouse effect, generates a large quantity of oxygen and protects the shore from waves and storms.

It’s continuous disappearance is a real concern for us, as it is very difficult to reproduce Posidonia. It takes approximately 200 years.

We don’t know how to plant them. If we lose a sample - we lose it forever.

For example, there was a large Posidonia oceanica meadow in Valencia, but it was destroyed because of pollution and it will take centuries without pollution to recover. Presently, the beaches of Valencia suffer of strong regression, in part due to the lack of Posidonia oceanica. Now there is much less Posidonia oceanica than there was before.

We still have many existing species, but much less than there was before. The decline has been vastly progressing for the last 25 years.

Pollution of water is the main reason explaining disappearance of Posidonia in many areas. The quality of water is of vital importance as Posidonia develops only in clear water.

Before we could find Posidonia at 50 meters depth now we do not find it as deep - very rarely at 45 meters, if not 35 meters and for example at 18m max at scalp.

When we build ports we destroy a population of Posidonia and obviously it does not recover. For this reason we no longer build ports for 15/20 years in Spain.

4. Why an interaction with artists is important / interesting for you?

Scientists have gathered data demonstrating that the biodiversity of the Mediterranean sea is being intensively affected by humans, their actions and lifestyle.

People just do not realise how much the Sea has changed for the past 20-30-50 years.

The life of the Mediterranean Sea is inherently beauty. Therefore, a novice is delighted when observes it for the first time. This also happens in tropical seas. But this first impression is totally biased, because the novice has nothing to compare with. The truth, from scientist knowledge, is that the live and beauty we see in the Mediterranean sea today is only a very small fraction of how it was 50 years ago.

This is a delusion and it is a dangerous one. The truth is that water is getting polluted, biodiversity reduced, and we rarely can see crystalline water, any more, as was common nearly every day in the past… we are deprived of the beauty of the sea… So the first important thing of the science and art collaboration is to find the way of showing the contrast between what we observe today and what it was decades ago.

But the other one, more important mission is to draw attention of the general public to the existence of the issue, make people aware that their behavior/lifestyle/business can cause alteration in the population and even species extinction. And find solutions of how to avoid this, how to rescue and preserve marine biodiversity. Scientist have a lot of data, but they do not have tools/media/knowledge of how to communicate to people. While artists - they can appeal to the sensitive/emotional perception of the general public, express visually, convey important messages in a comprehensive way. And they also can find new creative solutions, perhaps futuristic or surreal, that scientist will never think of. But in collaboration they can come to something that will really work...

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