Interview: Global warming damages marine ecosystems in Adriatic: Croatia scientist

A Croatian scientist warned global warming has seriously affected marine ecosystems in Adriatic Sea and damaged biodiversity, calling for more joint efforts to tackle climate change ahead of the 2015 Paris climate conference (COP 21).

The rising of sea temperature has led to instability of marine ecosystems and become one of the critical topics in next 10 years, Jakov Dulcic, head of the Laboratory of Ichthyology from Institute of Oceanography and Fisheries in Split, Croatia told Xinhua.

He hoped the leaders make commitment in Paris to reach an agreement aiming to keep global warming below two degrees Celsius.

The main temperature of Adriatic Sea was around 20 degrees Celsius in the 20th century, but reached 27 degrees Celsius during recent 2 decades, a record high 31 degrees Celsius has been seen in recent years in the sea nearby Hver Island, the southern coast of Croatia, according to Dulcic.

He warned that "sea temperature could rise by about 3.5 degree at the end of 2100 if we do not take measures to control."

Rising sea temperature has affected not only the composition and quantity of phytoplankton and zooplankton, the food for fish, but also species of fish, subsequently the marine ecosystem, said Dulcic, the author of the book New Fish of Adriatic Sea and Mediterranean.

A total of about 40 new species of fish recorded in the Adriatic ichthyofauna in last ten years, including 14 Lessepsian migrants, a name given to the fish from the Red Sea and the Indo-Pacific following the operation of Suez Cannel after Ferdinand Lesseps the constructor of Suze Cannel, according to Dulcic.

Adriatic fishermen found, for example, in their nets more and more the subtropical and tropical fish, algae and snails, he said, adding that a flock of tropical dolphin fish, living in warm waters of Indonesia and the Atlantic have been seen in Pula, Istria Peninsula of northern coast of the Adriatic in Croatia.

"The scientists are working on if new species are threatening local and endemic species of the Adriatic, but it was sure that alien fishes are definitely a factor damaging the ecological and biological balance of all the communities of the Adriatic Sea," he said.

He added some species, such as Siganus luridus, are in competition for food completely suppressed and significantly reduce the number of native species, Bamboofish Salema.

Some alien species have a direct impact on the food chain, for example, Fish Bluespotted Cornetfish (Fistularia commersonii), an express predator favouring anchovies, girom, beech as food, does not have natural enemies in the new ecosystem that led to out of control of its numbers.

Thus, invasive species was believed as one of the main causes of threat to biodiversity worldwide, as well as in Croatian, he said.

"Any potential danger can cause permanent and irreversible consequences for the environment as a whole," he added.

He expected the comprehensive effects of climate change, combined with other factors, would certainly play an important role in shaping the flora and fauna of the Adriatic in the future.

He deeply hoped the world leaders reach an agreement at COP21, which will be held in Paris from Nov. 30 to Dec. 11, on tacking the climate challenges for the global community and to prevent its worst consequences from happening. Endit