Since 1990, the presence of 46 new species of fish has been recorded in the Adriatic Sea, some of which have already established their own populations, which means that they have settled permanently and reproduce there.
This, among other things, was said at the lecture "Invasive fish and crab gardens in Boka Kotorska and the Adriatic", which was organized by the Tivat City Library.
A very interesting lecture with plenty of data on the ecological changes that the Adriatic is undergoing was held by the ichthyologist dr Aleksandar Joksimović, director of the Institute of Marine Biology from Kotor (IBMK). He presented all aspects of the work of that scientific research institution, which celebrates its 60th anniversary this year and which, through five laboratories and one center, deals with research and monitoring of almost all aspects of life in the sea in the southern Adriatic. IBMK, among other things, has 14 doctors of science, and four doctoral students and professional associates each, and it cultivates a very successful international cooperation with colleagues-marine biologists from abroad, and so far the Institute has implemented more than 140 various scientific-research projects.
Speaking about climate changes and global warming, Joksimović said that they also reflect on the marine ecosystem, so the average temperature of the surface of sea water in the southern Adriatic in the period from 1990 to today is increasing by 0,03 degrees Celsius per year.
"Although it appears to be very little, the cumulative effects of the warming of the sea water in the Adriatic are very noticeable and multiple, especially from the aspect of creating an environment that is favorable for the inhabitation of certain plant and animal species in the Adriatic that are characteristic of warm, tropical seas", he said. is Joksimović.
He stated that in addition to natural influences through the movement of sea currents, the heat and salinity of sea water, the change of the living world in the Mediterranean and the Adriatic is also influenced by the opening of artificial waterways such as the Suez Canal, since its digging in 1865, the Mediterranean has been physically connected to the Red Sea. by sea, and through that way non-native species also enter the Mediterranean and the Adriatic, the so-called Lessepsian migrants. On the other hand, species from the Atlantic Ocean come to the Mediterranean through the Strait of Gibraltar, and species characteristic of the Black Sea basin through the Dardanelles. So far, about 60 new species of fish have entered the Mediterranean through the Suez Canal from the Red Sea and the Indian Ocean.
"Since 1990, Croatian and Montenegrin ichthyologists have recorded, identified and described a total of 46 new species of fish and crustaceans in the Adriatic, so that now, including native - autochthonous species, we have data on at least a total of 450 species that live in our sea" , said Joksimović, presenting in detail some of the new species of the shore such as the four-toothed, trumpeter, marble, blue runner, ocean puffer, star-eyed, yellow-mouthed barracuda, three-tailed, blue crab, two new species of grouper, up to the newest inhabitant of the Adriatic - the lionfish (dragonfish). .
The lion fish is particularly problematic because it is very poisonous, it has no natural enemies in the Adriatic, nor is it interesting for commercial fishing, and at the same time it is a predator that destroys numerous domiciled species of fish and marine organisms. Therefore, in Joksimović's opinion, the only way for the fish population to lion in the Adriatic is kept under control as much as possible, in the future it will have to be an organized targeted catch and destruction so that it does not completely take over the habitat. Some of the new species, such as the new two varieties of grouper, i.e. blue crab in particular, are commercially very interesting for fishing and placing on the market, but so far local fishermen, at least when it comes to blue crab, have not shown much interest in dealing with organized fishing. and by selling that catch. Joksimović added that the danger for native species and habitat from newly introduced marine plants is the algae caulerpa racemosa and caulerpa taxifolia, which originate from the waters of the Indian and Pacific oceans near Australia. Changes in the ecosystem also affect the increase in the population of certain native species of fish, such as the flounder, which is primarily interesting for sport fishing, but which, due to its aggressiveness, often causes significant damage to certain other domestic species important for commercial fishing, such as carp.
Joksimović said that IBMK cooperates very well with local fishermen and the wider community on the coast, on the plan of strengthening awareness and education about the problem created by non-native and invasive species. Through the LEK (Local Ecological Knowledge) project, IBMK has already conducted 30-minute interviews with over 100 professional and sport-recreational fishermen along the entire coast - from Igalo to Ada Bojana. On that occasion, data was collected from people who are in daily contact with the sea and life in it, about the presence of non-native and invasive species, the frequency of their roles, but also the trends that fishermen notice in the behavior, abundance and presence of resident species - especially those important for commercial expolation.
Bonus video:
