Portfolio management has been suggested as a tool to help implement ecosystem-based fisheries management. The portfolio approach involves the application of financial portfolio theory to multispecies fishery management to account for species interdependencies, uncertainty, and sustainability constraints. By considering covariance among species, this approach allows economic risks and returns to be calculated across varying combinations of stock sizes. Trade-offs between expected aggregate returns and portfolio risk can thus be assessed. We develop a procedure for constructing portfolio models to help implement ecosystem-based fisheries management in the northeastern United States, using harvest data from the National Marine Fisheries Service. Extending the work of Sanchirico et al. (2008), we propose a measure of excessive risk taking, which may be used by managers to monitor signals of nonoptimal harvests. In addition, we conduct portfolio assessments of historical commercial fishing performance at different accounting stances: the large marine ecosystem, the New England region, and the community (fishing ports). We show that portfolio analysis could inform management at each level. Results of the study suggest that excessive risk taking is associated with overfishing, and risk management is therefore important for ensuring sustainability.
Ecosystem-based Management (EBM)
Ocean and coastal management regimes are increasingly subject to competing demands from stakeholders. Regulations must not only address fishing, recreation, and shipping, but also sand and gravel mining, gas pipelines, harbor/port development, offshore wind and tidal energy facilities, liquefied natural gas terminals, offshore aquaculture, and desalinization plants. The growing variety and intensity of ocean and coastal uses increases the call for a more holistic, comprehensive, and coordinated management approach that recognizes the often complex relationships between natural and human systems. For both economist and non-economist audiences, this book describes ways in which economic analysis can be an important tool to inform and improve ecosystem-based management (EBM). Topics include modeling economic impacts, benefit-cost analysis, spatial considerations in EBM, incentives and human behaviors, and accounting for uncertainty in policy analysis. Throughout the book the authors elucidate the different kinds of insights which can be gained from the use of different economic tools. In this rigorous and accessible work, the authors defy the conventional stereotype that economic perspectives necessarily favor the greatest commercial development. Instead, they demonstrate how comprehensive economic analyses consider the full range of potential services offered by marine and coastal ecosystems, including the conservation of biodiversity and creation of recreational opportunities.
This report considers the main elements of an ecosystem-based management approach to MA state ocean planning and offers a framework of science and decision tools to support effective plan development and implementation.
The Massachusetts Ocean Partnership Fund (MOPF), a public/private collaborative, was formed to support efforts in Massachusetts to move toward comprehensive ocean management through implementation of an ecosystem-based approach. MOPF is producing a science plan as a basis for future work of the partnership. In order to set the science plan on the best possible footing, this gap analysis was developed to explore the science needed to support comprehensive EBM.
This report presents a review of current research (including data and monitoring activities) in Massachusetts coastal and marine waters, and where applicable, the wider Gulf of Maine. Also identified are the gaps in research, data, monitoring, infrastructure and funding. Data derived for this analysis came from two sources 1) a review of research priorities from 35 organizations and 2) interviews, conducted in January and February 2007, with experts representing a variety of disciplines, including but not limited to: economics, social science, physical oceanography, geology, marine biology, ocean and coastal management and user groups. Organizations and interviewees were chosen based on involvement in scientific activities and/or monitoring programs in Massachusetts waters. A smaller subset of federal agencies and national organizations working within the broader Gulf of Maine, but informed on Massachusetts issues, also were included. This was done to gain insight into Massachusetts’ role in the broader ecosystem context as well as to determine external influences on Massachusetts’ waters.
Ecosystem-based management requires greater attention to habitat conservation. We evaluate the importance of benthic habitats as space for shelter, feeding, and breeding by coastal fishes and motile invertebrates in four biogeographic regions of the eastern United States. The importance of different habitats changed with latitude. Soft sediments and riverine systems scored higher in northern regions, and marshes and coral reefs scored higher in the south. The importance of soft sediments is notable because environmental assessments often assume their ecological value is lower. Submerged aquatic vegetation was a key nursery habitat coast-wide. An important consideration is that anthropogenic impacts have altered habitat availability and use, and climate change is causing ongoing disturbance. Furthermore, distinct habitats should not be managed in isolation but rather as interconnected mosaics. Our approach, combined with information on status, vulnerability, and other ecological functions, can be used to evaluate trade-offs and develop habitat-management strategies.
This paper merges inclusive wealth accounting theory with ecosystem based management (EBM) to resolve two problems. First, we provide measures of an ecosystem’s contribution to larger scale sustainability accounts by enabling ecosystems to be better included in inclusive wealth measures. We show the ecosystems are better thought of as portfolios of assets, and the portfolio’s performance is depended on the performance of the underlying assets, including their interactions. Second, the wealth held in the ecosystem is an attractive headline index for EBM regardless of whether ecosystem wealth is ultimately included in a broader index. We generalize natural capital theory to approximate realized shadow prices (accounting prices) for multiple interacting stocks of biotic and abiotic assets and liabilities that comprise ecosystems. We apply our approach to the Baltic Sea ecosystem, focusing on the interacting community of three commercially important fish species; cod, herring and sprat. The accounting prices of the three species show decreasing patterns with larger stock accumulation. Our results reveal the “supporting value or regulation services” embodied in the shadow price of a species through its trophic influence on other species. Prey fish have greater shadow prices than would be expected based on market value and predatory fish have lower shadow prices than may be expected based on market value.
Over the past decade, Sechura Bay has become an important center for mariculture in Peru, where the Peruvian bay scallop (Argopecten purpuratus) is grown in bottom cultures. Currently, the business involves 5000 artisanal fishermen and yields an export value of more than 158 million US$ per year. However, intensity and area extent of cultivation activities continue to increase. Overstocking of scallops combined with critical environmental changes may cause mass mortalities and severe consequences for the ecosystem. Accordingly, the ecosystem-based assessment of the current situation and the determination of long-term sustainable limits to scallop culture for the bay are crucial. Using a trophic food web model, the further expansion of culture activities is explored by forcing scallop biomass to increase to four different levels (458, 829, 1200, and 1572 t km−2) and the impact on other groups and the ecosystem are investigated. The ecological carrying capacity (ECC) is defined as the maximum amount of scallop biomass that would not yet cause any other group's biomass to fall below 10% of its original biomass. Results suggest that (a) the current magnitude of scallop bottom culture (147.4 t km−2) does not yet exceed ECC, (b) phytoplankton availability does not represent a critical factor for culture expansion, (c) a further increase in scallop biomass may cause scallop predator biomasses to increase, representing in turn a top−down control on other groups of the system, and (d) exceeding scallop biomass levels of 458 t km−2 may cause other functional groups biomasses to fall below the 10% threshold. The applicability and potential of the here presented ECC simulations as an ecosystem-based approach to sustainable bivalve culture are discussed. Results of this study are expected to guide both local fishers and managers in their challenging task of finding sustainable long-term levels for this important socio-economic activity in Sechura Bay.
While historically many coastal habitat conservation activities have focused on single projects and “low-hanging fruit,” there is increasing interest in strategically addressing habitat challenges at landscape scales. Zooming out to identify large-scale conservation needs and areas of greatest impact can yield significant ecological and economic benefits, but requires a new way of thinking and working that can be challenging. Based on a session convened at the Restore America's Estuaries/The Coastal Society Summit in November 2014, this article explores the concept of landscape-scale conservation, describes how it aligns with the National Oceanic and Atmospheric Administration Habitat Blueprint initiative, and provides case studies of ongoing landscape-scale efforts in three coastal areas: the Cape Fear River in North Carolina; the Russian River Watershed Habitat Focus Area in California; and the West Hawai‘i Habitat Focus Area. These examples illustrate both the benefits and the challenges of taking a landscape-scale approach to habitat conservation. While a landscape-scale approach provides a strong framework for planning, in practice success also depends heavily on building strong partnerships, engaging stakeholders, and maintaining flexibility to adapt to changing conditions and take advantage of opportunities as they arise.
Ecosystem-based fisheries management (EBFM) is often discussed by fisheries managers and stakeholders as a potential goal. EBFM is based on a multi-species approach, which varies significantly from the single species fisheries management (SSFM) approach currently practiced under the U.S. Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA). EBFM is “holistic” and considers “all factors,” but it is impossible for management to incorporate all factors into EBFM. This study sought to improve understanding of factors contributing to or preventing progress toward EBFM implementation in the Mid-Atlantic Fishery Management Council (MAFMC) and New England Fishery Management Council (NEFMC), focusing on Council member and stakeholder beliefs, attitudes, and mutual understanding. Objectives included determining mutual understanding between MAFMC and NEFMC members and stakeholders about EBFM and identifying MAFMC and NEFMC member and stakeholder preferences for EBFM definitions, practices, and outcomes, and prioritizing which aspects of EBFM managers and stakeholders find most important. Stakeholders included commercial fishermen, recreational anglers, nongovernmental organization (NGO) leaders, and Scientific and Statistical Committee (SSC) members. Over 1000 survey responses about EBFM from council members and stakeholders in the Mid-Atlantic (MA) and New England (NE) regions were analyzed. The Coorientation Model was used to characterize understanding between the Council and fisheries-related stakeholder groups. For the MA and NE regions, most stakeholders agreed on definitions, practices, and possible outcomes for EBFM. Results suggest that most Council members and stakeholders in the MA and NE regions support a change from SSFM to EBFM at an incremental, intermediate, or complete, gradual (5–10 years) pace. The application of the Coorientation Model to EBFM and the fishery management councils provided insights into how an improved understanding of the attitudes, beliefs, and mutual comprehension of Council members and stakeholder groups could potentially facilitate the implementation of EBFM. Council members and stakeholders responded similarly to, and Council members correctly predicted stakeholder responses about, EBFM definitions, practices, and outcomes. These findings suggest that Council member and stakeholder agreement and understanding are not barriers to MAFMC and NEFMC adoption of EBFM.
Ecosystem-based approaches to fisheries management (EAFMs) have emerged as requisite for sustainable use of fisheries resources. At the same time, however, there is a growing recognition of the degree of variation among individuals within a population, as well as the ecological consequences of this variation. Managing resources at an ecosystem level calls on practitioners to consider evolutionary processes, and ample evidence from the realm of fisheries science indicates that anthropogenic disturbance can drive changes in predominant character traits (e.g. size at maturity). Eco-evolutionary theory suggests that human-induced trait change and the modification of selective regimens might contribute to ecosystem dynamics at a similar magnitude to species extirpation, extinction and ecological dysfunction. Given the dynamic interaction between fisheries and target species via harvest and subsequent ecosystem consequences, we argue that individual diversity in genetic, physiological and behavioural traits are important considerations under EAFMs. Here, we examine the role of individual variation in a number of contexts relevant to fisheries management, including the potential ecological effects of rapid trait change. Using select examples, we highlight the extent of phenotypic diversity of individuals, as well as the ecological constraints on such diversity. We conclude that individual phenotypic diversity is a complex phenomenon that needs to be considered in EAFMs, with the ultimate realization that maintaining or increasing individual trait diversity may afford not only species, but also entire ecosystems, with enhanced resilience to environmental perturbations. Put simply, individuals are the foundation from which population- and ecosystem-level traits emerge and are therefore of central importance for the ecosystem-based approaches to fisheries management.