“We know much, but there are still many habitats that are poorly studied , such as deep sea areas . Many groups of organisms is not well known , especially smaller ones, and even there are significant knowledge gaps more visible groups such as fish or marine mammals , “says Marta Coll SINC , a researcher at the Mediterranean Centre for Marine Research and Environmental ( CMIMA ) of the CSIC, who led the work of synthesis on marine biodiversity of the Mediterranean.

Australian and Japanese waters , home to nearly 33,000 respectively scientist named species , among which the white shark (Carcharodon carcharias), Are hosting more diversity. China ‘s oceans , the Mediterranean and the Gulf of Mexico complete the five areas with the greatest diversity of species known . Inventories of Indonesia , Madagascar and the Arabian Sea are still under development and awaiting delivery.

In the case of the Mediterranean Sea , experts show that has a great marine biodiversity , “which is distributed heterogenia and focuses on areas of western Mediterranean, Adriatic and Aegean, and North Africa , “says Coll holding that “only known part of this biodiversity , there are many undiscovered species and areas for study , especially in areas east and south. ”

The Mediterranean has 2,000 endemic species , like the waters of the Caribbean, China, and Japan. The regions with the highest number of endemic species are that they are isolated as Australia (25 % endemic species ), New Zealand (25 %) , Antarctica and South Africa (50 % endemic species both regions) .

The situation is delicate fish in the Mediterranean. Fish are only between 3 and 6 % of the species in this region. However, the Mediterranean is the one with the highest number of invasive species: 600 (4% of the total lack of species recorded ). Most of them have come from the Red Sea to the Suez Canal . Molluscs , crustaceans and fish are the most common invaders .

According to the Spanish researcher at present Mediterranean marine biodiversity ” is threatened by many human activities such as overfishing and habitat destruction , pollution and eutrophication , invasion of alien species and climate change impacts , among other factors. ” Furthermore, the Census states that the biodiversity of closed seas , like the Mediterranean , the Gulf of Mexico platforms for China, the Baltic and the Caribbean, is the most threatened .

” The Mediterranean Sea may be reaching an extreme situation where large areas are not protected and given priority to sustainable resource management by controlling the different causes of impact on marine biodiversity , “says Coll.

Shellfish , the largest group

According to the Census 360 scientists , who publish the inventory PLoS OneThe total number of known plant and animal species and name assigned between 2600 and 33,000 , with an average close to 10 750 . These species belong to a dozen of taxonomic groups. One-fifth of the species are crustaceans (19 %) which, together with the molluscs (17 % ) and fish (12 % including sharks ) , constitute about half of all known species in the different regions.

The rest are ” other invertebrates “(5 %) and ” other vertebrates “(2 % ), which includes whales , sea lions , seals , seabirds , turtles and walruses. This shows that some of the best-known marine animals represent only a fraction of marine biodiversity. But ” the biodiversity of microscopic organisms is virtually undescribed , so that it is difficult to know which group of organisms are most abundant in our oceans , “said the scientist.

When present on 4 October last Census estimate in London ( England) , it is likely that the figure exceeds the 230,000 species, since many of them have yet to join the World Register of Marine Species (which has a list of 185,000 marine species ) and Biogeographic Information System ( OBIS ), which represents over 30 million records on projects and 800 databases.

New species and species to be discovered

According to Coll, the investigations have uncovered to date 1200 marine species new to science . To these are added to the undescribed species is estimated to represent 39% to 58 % in Antarctica , 38 % in South Africa , 70 % in Japan , 75 % in the deep waters of the Mediterranean, and over 80 % In Australia.

“To create this basis , the Census of Marine Life has explored new areas and ecosystems , discovering new species and generating appointments of known species in new places , “said Patricia Miloslavich , scientific senior Census , director of regional studies and research at the Universidad Simón Bolívar ( Venezuela).

However, a study recently published in the journal Zootaxa, Showed that remain to be discovered and described about 5,000 species of marine fish ( twice as many that have been described in the last 19 years), with an estimated total of about 21,800 marine fish species worldwide .

Scientists from the Census of Marine Life have combined the information generated in recent centuries with data obtained during the census , which began in 2000 . The work will guide future decisions for research in unexplored waters .

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References:

Marta Coll , Chiara Piroddi , Jeroen Steenbeek , Kristin Kaschner , Frida Ben Rais Lasram , Jacopo Aguzzi , Enric Ballesteros , Carlo Nike Bianchi , Jordi Corbera, Dailianis Thanos , Roberto Danovaro , Marta Estrada , Carlo Froglia , Bella S. Galil , Josep M. Gasol, Ruthy Gertwagen , Joao Gil , François Guilhaumon , Kathleen Kesner -Reyes, ” Spyridon Kitsos Miltiadis , Koukouros Athanasios , Nikolaos Lampadariou , Elijah Laxamana , Carlos M. López- Fé de la Cuadra, Heike K. Lotze , Daniel Martin , David Mouillot , Daniel Golden , Sasa Raicevich , Josephine Rius – Barile , Jose Ignacio Saiz -Salinas, San Vicente Carles , Samuel Somoto Jose Temperate , Xavier Turon , Dimitris Vafidis , Roger Villanueva , Eleni Voultsiadou . “The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats . ” PLoS
ONE 5 ( 8) | e11842 , August 2010.

Mark John Costello , Marta Coll, Roberto Danovaro , Pat Halpin, Ojaveer Henn , Patricia Miloslavich . “A Census of Marine Biodiversity Knowledge , Resources, and Future Challenges . ” PLoS ONE. 5 ( 8) | e12110 , August 2010.

Source: SINC