Authors:Dr. Dmytro Cheberkus and Sophia Zherebchuk
In XXI century everyone in our planet become to understand how fragile the ecosystem is. The key words in every ecosystem description tie with equilibrium and stable balance. This equilibrium or stable balance could be destroyed due to the invasion of new species, the death of existing species, natural disasters or man-made causes. Advocates of an environmental ethic consider that the best way for protect ecosystem is to leave it alone, not interfere, and let nature follow its own course. Certainly, there are many cases of appropriate human interference. But the qualified assessment should be the obligatory component in every case, especially within the EU instruments or projects.
The Black sea basin is most contradicting regarding political and security issues and the most polluted sea basin in EU. Today, the Black sea has serious problems with eutrophication, pollution and colossal impact of the biota invaders of rapana, mnemiopsis and other species. Besides the Black sea suffers from exosystemic harm caused by human interference. In this regards, the Ukrainian authorities should take all necessary protection measures.
But without deep scientific assessment any activity could become a disaster for the Black sea, like many years ago the human impact caused the death of Aral Sea.
If we are talking about case study, we need to put the stress on several projects that implement without any social and ecological assessment and in the same time could cause ecological disaster.
In the end of 2020, near Mykolaiv on the Kinburn spit on top of the allegedly existing natural mussel field “artificial reef” was created. Shells of imported oysters from the garbage heap of a restaurant selling live imported oysters in plastic bags have become one of the materials for this reef. But such a “unique” solution is extremely dangerous for the Black Sea ecosystem. Organisms, larvae and their eggs, as well as infectious diseases that live in the overgrowth of shells and oyster meat are alien to the local fauna and may become new harmful invaders – aliens for the Black Sea.
Besides 2.5 tons of oyster shells the project participants also dropped into sea the plastic bags and other garbage like rusty metal, which during decomposition will also pollute the Black Sea with extremely dangerous microplastics.
Thousands of Black sea mussels caused by this experiment are just died under the garbage bags that were placed over them. Thus, part of mussels that could cleanse the sea by filtering the water were blocked and became victims of rapana. 100 bags of garbage lay on the “carpet” of mussels and a pyramid on top of each other around the rusty pipes, blocking the possibility of filtering water on the mussels and leading to their partial death.
Also the plastic bags with a fine mesh were used for reef’s construction. No need to remind what is the ecologists opinion about the fact that abandoned (forgotten, lost) in water plastic fishing nets for years (until they collapse) continue to catch and destroy fish, crabs and other inhabitants of the sea, who become entangled in them and perish. Thousands aquatic organisms like crabs, shrimps, fish may be, and will be in this trap and die when will not be able to leave. This is not about biodiversity increasing of the Kinburn Spit.
At the same time, many unsuccessful construction attempts of reefs from unnatural materials are known: car tires, plastic waste etc. These reefs were destroyed and polluted the coast and sea-ocean. The material for sprouting (the plastic bag) is on the surface, the oyster’s shells are inside and they not sprout.
Also, we should remember that there is currently no oyster nursery in Ukraine; landing material (spat or grown juvenile oysters) is imported either from Europe (France, Spain, Ireland, England, etc.), or from the Far East (Sakhalin). Import to Black Sea associated with the risks of bringing dangerous infections into this region. It is known that state and industrial control over dangerous diseases of oysters is ineffective.
Oysters, like many other bivalve molluscs, are susceptible to various diseases. The causative agents of oyster diseases can be viruses, bacteria, fungi and protozoa, and also various types of worms and crustaceans. The degree of knowledge of diseases of different the types of oysters are significantly different. Usually oyster diseases are most commonfound in places of their mass concentration (oyster banks) and areas cultivation of molluscs. Mycoses are a serious danger to oysters, caused by parasitic fungi. The most dangerous and widespread disease of oysters of fungal etiology is shell disease, caused by the fungus (Ostracoblaba implexa).
Shell disease in the Black Sea for the first time registered in 1975, was found on all the largest oysters in the northwestern part of the Black Sea. Given the high degree of oyster infestation (up to 99 %) it, apparently, was one of the reasons for the mass degradation of natural populations of this species in the northwestern part of the Black Sea. Currently European oyster in the Black Sea is on the verge of extinction, listed in the Red book of Ukraine.
Other possible reasons for the decline in the number of European oysters in Black the sea is considered to be cumulative toxicosis caused by pollution of marine areas, deterioration of hydrochemical (oxygen) and hydrobiological (feed) conditions habitats due to the eutrophication of offshore areas, as well as a wide distribution in the Black Sea of ​​a predatory introduced species – the gastropod mollusk rapana (Rapana venosa).
Despite the extensive list of infectious diseases known in oysters we have a few experts in Ukraine regarding oysters’ diseases. Experience in oyster farming in the Black Sea has shown that some local diseases of molluscs, such as shell disease, clionosis, hexamitosis and others can also infect oysters imported into this region.
Accommodation in the water area of ​​the nature reserve fund of various types of adult oysters grown in areas remote from the Black Sea should be strictly prohibited due to the high risks of infectious diseases and harmful invaders.
Another example of harmful actions is the decision of Mykolaiv regional authority about lend sales in the Sviatoslav National Nature Park that included in the Emerald Network of Europe. In the case of the implementation of these plans the orchid field will be finally lost, millions of rare plants and animals listed in the Red Book of Ukraine will be under threat.
In this regard, the approach to the projects’ implementation should be changed on national and international level. United Nations Convention on the Law of the Sea of 10 December 1982 already has the provisions regarding the protection and preservation of the marine environment as far as marine scientific research. Ukrainian authorities should apply these provision and guarantee that every interference into Back sea ecosystem should accompany with deep scientific assessment.
The in EMBLAS project in Ukraine. With the aim of strengthen the capacities of Georgia, Russia and Ukraine for biological and chemical monitoring of water quality in the Black Sea in line with EU water-related legislation EU and UNDP established the improving Environmental Monitoring in the Black Sea (EMBLAS) project.
The international initiatives (within EMBLAS, UNDP, World Bank, CMA etc.) are really important and could be the powerful tool for ecological monitoring and capacity building I the Black sea.
