The action was specified and modified in the direction of using modern methods of communication with the society (websites and channels in social media, websites dedicated to aquaristics or fishing, magazines: including Akwarium and Wiadomosci Wedkarskie). It is planned to involve in the information campaign representatives of science (NMFRI, Inland Fisheries Institute, Institute of Nature Conservation, Institute of Environmental Protection), environmental and social organizations such as: WWF, Polish Association of Aquarists and Polish Angling Association, as well as leading aquarium and fishing stores. Promotional materials should indicate the significant problem of alien species and their expansion, facilitated by the uncontrolled release of aquarium fish and fish used as fishing baits, as well as arbitrary restocking (not in accordance with the fishing survey). Such activities endanger native species and the stability of aquatic ecosystems. """"

When modified, the action will focus on the practical implementation of the guidelines contained in Resolution MEPC.207 (62). An expert opinion will be made on how Poland has implemented Resolution MPEC.207 (16). This expertise: - it will contain an analysis of anti-fouling practices on ships with Polish origin as well as in Polish shipyards and ports in terms of their compliance with the MPEC.2017 resolution (6), - present examples of good practice in the implementation of Resolution MPEC.2017 (6) by other IMO member states, - indicate the elements of the guidelines of Resolution MPEC.2017 (6), which should be implemented in the form of provisions binding on ships of Polish origin, as well as on Polish shipyards and Polish ports, and will include proposals for draft legal acts in this regard, - identify the elements of the guidelines of Resolution MPEC.2017 (6) that should be implemented in the form of codes of good practice or through training and other non-legal measures, as well as responsible actors and potential sources of funding. Proposals of draft legal acts included in the expert opinion will be subject to a legislative process according to the rank of the drafted acts.

The action involves the preparation of a stocking program with predatory species (pikeperch, pike, eel) for each of the bodies of surface water. Stocking doses and assortment will be determined for each body of surface water. The aim of the activity is biomanipulation leading to the limitation of the expansion of Round Goby and other invasive species of goby in these reservoirs by increasing the pressure of predators on these species (zander and pike feed on adults, and eel can eat goby roe). The results of the project """"Restitution of the key elements of the ecosystem of the Inner Bay of Puck (ZOSTERA)"""", implemented with the use of the Infrastructure and Environment fund, including pike and zander stocking in order to reduce the population of stickleback fish and round goby, will be used. The next task will be to obtain an appropriate amount of stocking material for zander and pike - from spawners from the catchment area of ??rivers flowing into individual transistional water bodies (in order to maintain genetic diversity), as well as eel stocking, and to conduct systematic annual stocking for 5 years. At the same time, registration of fishing and recreational catches of the introduced predatory fish species will be carried out on each of the reservoirs, as well as annual monitoring of the presence of round goby and other invasive goby species. In order to determine the share of goby fish in the diet of zander and pike in two selected waters (eg the Vistula Lagoon, the Kamienski Lagoon), an analysis of the digestive tract content of these species should be performed. The tests should be performed for a sample of zanders and pikes of various sizes (total length 20-80 cm), obtained from fishing and experimental catches (undersized individuals). The analysis should be carried out for 3 consecutive years, starting from the 2nd year of the commencement of restocking, on a sample of at least 200 individuals of each species per reservoir per year. As part of the measure, the impact of restocking on protected fish species should also be assessed. Data from the State Environmental Monitoring will also be used to evaluate the project results. These analyzes will be the basis for the preparation of the continuation and possible modifications of the program for the coming years. An additional supporting activity will be a promotional campaign aimed at promoting round goby consumption. In the 1960s and 1970s, round goby imported from the Black Sea region were a valued product, nowadays, canned goods of this trade name predominate on the market, but produced from other species of fish, including freshwater. The creation of a sales market will enable the economic exploitation of goby fish, which will contribute to the reduction of their numbers.

The action will consist in conducting intensive catches of American crayfish in the Vistula Lagoon. The experience with harvesting in other countries so far shows that it is practically impossible to eliminate the species, but it is possible to significantly reduce its number. As part of the action, several types of traps will be used, including the so-called """"habitat traps"""", which, in the light of the available literature, are the most effective. New types of traps developed as part of the measure will also be tested. The activity is a pilot activity and, apart from the reduction of the American crayfish population, it aims to answer the following questions: - which traps are the most effective in Polish conditions, - what are the size and sex distributions of captured individuals, - what are the relationships between hunting and the nature of the habitats, - what is the selectivity of the traps (share in half of species other than American cryfish) and whether the catch has an effect on protected fish species, - what are the recommended methods of dealing with caught crayfish, - whether and how quickly the number of captured individuals decreases, which is a measure of the size of the population in the water, - what are the practical difficulties in the implementation of catches and how to overcome them (e.g. the problem of vandalism or theft of traps), - what are the costs of catching (labor, fuel, materials), - how quickly the crayfish population recovers from intensive catches, - what is the importance of American crayfish in the food web as a fish food and what changes in the direction of predation pressure and in the structure of the food web can be expected as a result of the reduction of the crayfish population.

The action will consist in catching Chinese mitten crab in places constituting potential bottlenecks in seasonal migrations of this species on the western outskirts of Poland, i.e. in the Odra River near Police, in Dziwno and Swina, as well as in the Szczecin Lagoon and the Pomeranian Bay. The aim of the action will be, on the one hand, the reduction of the Chinese mitten crab population, and, on the other, - obtaining a constant source of information about the intensity of the expansion of this species, which reaches Poland from the North Sea catchment area, and about possible breeding attempts made by this two-environmental species. It is generally recognized that a barrier to reproduction in the Baltic Sea of ??Chinese mitten crab is too low salinity. Nevertheless, egg-bearing females have been observed not only in the western Baltic (Germany), but once even in the Gulf of Gdansk. The area from the estuary of the Odra River to the Pomeranian Bay seems to be the most suitable area of ??Poland for the reproduction of Chinese mitten crab. Harvesting there will, on the one hand, hinder the expansion of this species, and on the other hand, provide information about possible reproductive behaviors (seasonal migration, laying eggs). As far as equipment is concerned, it is anticipated that the most effective types of traps according to the literature will be used for catching, including those used in Flanders (Schloenyck, 2020). In addition to the answers regarding the scale of colonization and perinatal and reproductive behavior, the action should result in conclusions regarding the optimization of further protection against Chinese mitten crab, e.g. in terms of types of traps, places and times of trapping, organization of work, protection against theft and vandalism, etc. These conclusions should take the form of a best practice handbook to be used also in other regions of Poland. As part of the measure, possible impacts of harvesting on protected fish species should also be assessed. It seems that the most effective way of implementation will be to award the contract to an entity that brings together scientists, professional fishermen and non-governmental organizations.

The activity will be of a research and pilot nature, and its possible results will serve in subsequent planning cycles as the basis for more extensive activities aimed at the fullest possible restoration of the seaweed and fork meadows in the Puck Lagoon. The action will include: – collection and analysis of available literature on occurrence, morphology, biology and causes of the disappearance of the seaweed and forkbeard in the Puck Lagoon, - to investigate by genetic methods the relationship between herbarium specimens of hake and forkbeard from the Puck Lagoon and seaweed and forkbeard from other Baltic and northern European populations, including primarily free-floating forms inhabiting the sandy bottom (Fucus vesiculosus forma baltica, Furcellaria lumbricata forma aegagropila), - review of previously developed or proposed methods of propagation and breeding of seaweed and forkbeard under controlled conditions for research, commercial purposes or to obtain material for entering the environment, with particular emphasis on free-floating forms, – selection of breeding and breeding methods potentially best suited to the conditions of the Puck Lagoon, - mastering and improving the methods of reproduction and breeding, both in laboratory conditions and in controlled in situ conditions (separated """"plots"""" in the area of former occurrence of seaweed meadows), - conducting under controlled in situ conditions a series of experiments to determine the effects on individual and population development of factors such as starting genetic material, exposure/depth, exposure to undulation, competition of opportunistic species, feeding on the backs of invertebrates and fish, etc., - a multifaceted analysis of the current state of the area of former seaweed meadows, with particular emphasis on the conditions and internal and external threats that may be important for the chances of success of the programme, - publication of the obtained results and development of guidelines / recommendations for further actions for the restoration of seaweed meadows in the Puck Lagoon.