Optimal sustainable fishery management of the Black Sea anchovy with food chain modeling framework

Abstract

Food chain models with interactions between key species are useful tools for ecological conservation and economic sustainability in commercial fisheries. In this study, we build a food chain model coupled with optimal control theory and focus on the Black Sea anchovy population in the southern part of the Black Sea. Our objective is to find the optimal harvesting strategy that maximizes the discounted net profit value of the anchovy fishery with seasonal harvesting, and that offers sustainable anchovy fishery. As a result, we obtain profitable and sustainable harvesting strategies.We also discuss the benefits of using food chain models in fishery management rather than using single-species models. Finally, we derive a schedule for the number of fishing vessels that are needed in the implementation of the optimal harvesting strategy. Recommendations for Resource Managers• Food chain modeling framework offers more reliable harvesting strategies than single-species modeling framework.• Managing the harvest effort using optimal control theory results in a more profitable anchovy fishery on the southern part of the Black Sea.• By quantifying the relationship between the annual landing and the number of fishing vessels, we can approximate the needed number of fishing vessels to achieve an optimal landing. • Applying an optimal control strategy yields more anchovy landing and profit in the long term, when we compare with the current harvesting strategy used in the anchovy fishery. These strategies also offer a sustainable anchovy fishery, which is crucial for the fate of this fishery.

Sustainable Brand Management of Alimentary Goods

“…In order to achieve these changes in so far functioning stereotypes, the issue of brand and brand management should be highlighted. But the fact that alimentary goods are characterized by traditional habitual buying behavior creates a specific obstacle to such an approach, because the reason is that, in this type of buying behavior, consumer's loyalty is the leading motivation for purchase whether or not the brand is socially responsible on the market [5,6]. The above-mentioned fact can be considered as a real problem when seeking to achieve sustainability in scope of food production and consumption.…”

A spatial food chain model for the Black Sea Anchovy, and its optimal fishery

“…The use of food chain models focusing on the key species on ecosystems becomes an increasingly useful trend in the commercial fishery to not only conserve and manage natural renewable food resources, but also to have sustainable and productive ecosystems (e.g. [17]; [36]; [1]; [19]; [37]; [4]).…”

“…In these studies, a single PDE is used for the stock and the models used in these studies do not represent a specific fishery scenario, but we use a system of PDEs for the Black Sea anchovy fishery in the Black Sea, which is a specific fishery. Building on the optimal harvesting results for a food chain ODE model of the Black Sea anchovy in [4], we use three trophic levels in our PDE system. This application with spatial-temporal features for the Black Sea anchovy coupled with optimal control theory is novel.…”

“…Section 4 gives the derivation of the optimality system, which consists of the state equations, the adjoint equations, and the characterization of optimal control. In Section 5, we first obtain the parameters of our model by choosing parameters adjusted by using landing data and some rates from [4]. Then we present numerical solutions to our optimality system for some scenarios and connect these optimal harvesting results to fishery management of the Black Sea anchovy.…”

“…For our numerical simulations, the rates are obtained from using the data of Black Sea landing in [35] and from appropriate adaption of the parameters in [4]. The initial total biomass for zooplankton was found from [4] when anchovy population is near its lowest biomass and placed spatially due to the known location at that time (coming in from the north part of the Black Sea). For the advection rate of 0.18 in Table 1, we used the known distance of the migration of the anchovy over the months in our simulation.…”