Towards the Optimal Management of the Northeast Arctic Cod Fishery

The objectives pursued by governments managing fisheries may include maximizing profits, minimizing the impact on the marine ecosystem, or securing employment, which all require adjusting the composition of the fishing fleet. We develop a management plan that can be adapted to those objectives and allows the regulator to compare the long-run profits between the various management options. We apply the model to the case of Northeast Arctic cod, and estimate the cost and harvesting functions of various vessel types, the demand function, and a biological model to provide key insights regarding the optimal management of this valuable fish species.Built Coastal Environment, Natural Coastal Environment, Ecosystem Service Valuation, Geographic Information Systems, Mapping Ecosystem Values, Marine Biodiversity, Scaling up, Spatial Analysis, Spatial Economic Valuation, Value Transfer

Contagious cooperation, temptation, and ecosystem collapse

AbstractReal world observations suggest that social norms of cooperation can be effective in overcoming social dilemmas such as the joint management of a common pool resource—but also that they can be subject to slow erosion and sudden collapse. We show that these patterns of erosion and collapse emerge endogenously in a model of a closed community harvesting a renewable natural resource in which individual agents face the temptation to overexploit the resource, while a cooperative harvesting norm spreads through the community via interpersonal relations. We analyze under what circumstances small changes in key parameters (including the size of the community, and the rate of technological progress) trigger catastrophic transitions from relatively high levels of cooperation to widespread norm violation—causing the social–ecological system to collapse

Positive framing does not solve the tragedy of the commons

We investigate whether positive framing increases cooperation in three social dilemmas with slightly different properties: a linear public goods (PG) game, a non-linear PG game, and a common pool resource (CPR) game. Results from our laboratory experiments show that contributions to a linear PG are higher if the externality is framed positively, rather than negatively, corroborating earlier findings by Andreoni (1995). By contrast, we find no such framing effects in the non-linear PG game or the CPR game. In these games, the best response in the material payoffs is to contribute less if others contribute more, counteracting effects of pro-social preferences. Positive framing therefore does not help to solve the tragedy of the commons

Tragedy, property rights, and the commons: investigating the causal relationship from institutions to ecosystem collapse

Do private property rights mitigate overexploitation of common pool resources, and if so, under which circumstances? In this paper, we examine the effects of private property rights on the status of marine fisheries by combining data on ecological, economic and institutional characteristics into a panel data set, spanning over 50 years, 170 exclusive economic zones and 800 species. To address the inherent endogeneity problem of policy implementation, we employ both a difference- in-differences (DiD) and instrumental variable (IV) strategy. Results from both estimations suggest that property rights lower the probability of a fish stock collapsing, but the effect varies with country and species characteristics. Specifically, we find evidence suggesting that property rights are more effective when ownership is transferable, the general level of ownership protection is strong, trade openness is high, the regenerative capacity of the resource is high, and the species value is high

Alpha managers - an advantage or disadvantage for the organization

The role of the manager is crucial to the organization. Managers set goals, develop strategies and define tasks of workers, create environment for the development of people and give meaning to their activities. Professional skills are of vital importance to manager’s success. These very skills are the distinguishing characteristics of alpha managers. The aim of the following paper is to present some of the most established ideas in the field of leadership styles, to compare them with the concept of alpha managers and draw some conclusions important to management

A bio-economic analysis of harvest control rules for the Northeast Arctic cod fishery

-Harvest control rules (HCRs) have been implemented for many fisheries worldwide. However, in most instances, those HCRs are not based on the explicit feedbacks between stock properties and economic considerations. This paper develops a bio-economic model that evaluates the HCR adopted in 2004 by the Joint Norwegian–Russian Fishery Commission to manage the world's largest cod stock, Northeast Arctic cod (NEA). The model considered here is biologically and economically detailed, and is the first to compare the performance of the stock's current HCR with that of alternative HCRs derived with optimality criteria. In particular, HCRs are optimized for economic objectives including fleet profits, economic welfare, and total yield and the emerging properties are analyzed. The performance of these optimal HCRs was compared with the currently used HCR. This paper show that the current HCR does in fact comes very close to maximizing profits. Furthermore, the results reveal that the HCR that maximizes profits is the most precautionary one among the considered HCRs. Finally, the HCR that maximizes yield leads to un-precautionary low levels of biomass. In these ways, the implementation of the HCR for NEA cod can be viewed as a success story that may provide valuable lessons for other fisheries

Optimal management under fleet constraints: the case of Northeast Arctic cod

The objectives pursued by governments managing fisheries may include harvesting the fish stocks to maximize profits, to minimize the impact of harvesting on the marine ecosystem, or to secure jobs in the fishing industry. These objectives all depend on the composition of the fishing fleet as the various vessel types differ with respect to their operating costs, their environmental impacts, or how these boats provide employment opportunities on board or on shore. The Norwegian cod fishery consists of a fleet comprising coastal vessels, large longliners, and the fleet of trawlers and factory trawlers. These vessels score differently when it comes to meeting and reconciling these different objectives, and have therefore received mixed political support. In this paper, we develop an analytical model that shows the optimal TAC, biomass level, and long-run profits taking specifically into account fleet composition. This allows a regulator to adapt optimal management to the current fleet structure, but also analyze the bioeconomic consequences of a change in fleet structure (e.g. a ban on factory trawlers). We specifically take into account the occurrence of a fleet lock in, which means that the fishing fleet cannot be adjusted instantaneously, as several vessels cannot leave the fleet because of economic or political constraints. We apply the model to the case of Northeast Arctic cod, and econometrically estimate not only the cost and harvesting functions of the various vessel types, but also the parameters of the biological model as well as those of the demand function for cod

The Economic Repercussions of Fisheries-induced Evolution

Human-induced changes in life-history traits have been observed for many harvested populations, with a component of those changes being attributed to an evolutionary (i.e., genetic) response. Most notably, fish stocks that experience high fishing mortality show a tendency to mature earlier and at a smaller size. Some have suggested that fisheries-induced evolution could affect the fishery’s yield and therefore have economic repercussions for society. Yet, this has not been formally investigated. We use data from 1932 to 2005 to develop a bio-economic model specifically for Northeast Arctic cod that allows us to compare the economic yield in scenarios with and without evolution of key life-history traits. We also compare a “business as usual” scenario where fishing continues at its current pace, with a scenario in which harvest is controlled through an optimal control rule. Our model predicts that fisheries-induced evolution decreases economic yield if fishing mortality rates continue at their current high levels. We also find that maximum economic yield is achieved at a considerably lower fishing mortality than what the stock has historically experienced. At this lower mortality, fisheries-induced evolution is less pronounced and actually increases the spawning stock biomass and economic yield. Overall, we find that evolutionary and non-evolutionary models recommend similar harvesting rates and the overriding message is that higher economic yield can be obtained by lower harvest rates irrespective of whether evolution occurs or not

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes