In the context of ecosystem-based fisheries management, which should consider changing and uncertain environmental conditions, the development of ecosystem-based biological reference points (EBRPs) to account for important multi-species (MS) interactions, fishery operations, and climate change, is of paramount importance for sustainable fisheries management. However, EBRPs under varying plankton productivity states and fisheries management strategies are seldom developed, and the ecosystem effects of these changes are still largely unknown. In this study, ecosystem-based FMSY(fishing mortality rate at MSY) values were estimated within an end-to-end ecosystem model (OSMOSE) for three focused fish species (Pacific Herring, Clupea pallasii; Pacific Cod, Gadus macrocephalus; Lingcod, Ophiodon elongatus) under three plankton productivity states of differing plankton biomass at high, current, and low levels. In addition, ecosystem effects were compared across different plankton productivity and fisheries management strategies with the latter consisting of two fishery scenarios (i.e. single-species-focused (SS) and MS-focused), various fishing mortality rates, and two harvest policies (with and without harvest control rules, HCRs). Main findings of this study include: (i) plankton productivity change affected the values of ecosystem-based FMSY, which increased as plankton productivity states changed from low to high plankton biomass; (ii) ecosystem-based FMSY for Pacific Herring and Pacific Cod stocks increased when fishery scenarios shifted from SS-focused to MS-focused; (iii) fisheries management incorporating HCR yielded more stable system catch and system biomass; and (iv) high plankton biomass combined with fisheries management using HCR could maintain stable ecosystem production and sustainable fisheries. Based on our findings, we highlight possible adaptive fisheries management strategies in the face of future climate and ocean changes. Overall, EBRPs complement SS stock assessments by incorporating key ecological processes and ecosystem properties, thus providing supporting evidence for better incorporation of ecosystem considerations into scientific advice for sustainable fisheries management.
Ecosystem-based Management (EBM)
This thematic issue on Asian Large Marine Ecosystems focuses attention on a major geographic area of the world where the goods and services of 13 Large Marine Ecosystems (LMEs) are serving the needs of three billion people inhabiting the region. The stressors affecting the sustainable development of the Asian LMEs are impacting the economies of the bordering countries from overfishing, pollution, nutrient overenrichment, habitat degradation, biodiversity loss, and climate change. The papers in this issue represent a cross-section of assessment studies underway by marine scientists, policy specialists, and resource managers in the region engaged in a movement to introduce ecosystem-based management practices for mitigating stressors on LMEs. This movement is supported, in part, by an independent international financial entity, the Global Environment Facility (GEF), which exists to help meet the objectives of international environmental conventions and agreements. The movement towards ecosystem-based management is supported by the GEF to advance a United Nations effort to assist economically developing nations in the Asian region and in other regions around the globe towards sustainable development of the oceans.
The expectations on marine spatial planning to improve environmental governance of the Baltic Sea are high, not least for helping to close the huge gaps between environmental objectives and the state of the marine environment. This article focuses on the on-going implementation of marine spatial planning in Sweden, well-known to be a forerunner in environmental policy. Aiming to identify governance recommendations, the study analyses how the first consultation document for the Baltic Sea may complement existing governance systems and promote gap closure. A particular focus is placed on the potential impact of the plan on the implementation of an ecosystem approach to management (EAM) and how these issues are regarded by involved stakeholders. It is shown that the planning process promotes participation, but that the studied plan as such most likely does not significantly help to close any larger environmental goal-state gaps. A number of recommendations on how to develop the plan are discussed, but significant improvements require broader governance reforms, in particular concerning coordination and integration in relation to legislation on other marine and water strategies, as well as policies and laws for fisheries, agriculture and industrial chemicals. Major policy development is thus needed in order to allow marine spatial planning in Sweden, and most likely in several other geographical areas as well, to significantly help closing goal-state gaps in the future.
East Asia encompasses six large marine ecosystems (LME): the South China Sea, the Gulf of Thailand, the East China Sea, the Yellow Sea, the Sulu-Celebes Sea, and the Indonesian Sea. Despite occupying only 3 percent of the world’s ocean surface, portions of this area are considered to be the global center of marine biodiversity. Since the early 1990s, Partnerships in Environmental Management for the Seas of East Asia (PEMSEA) has refined the Integrated Coastal Management (ICM) methodology and fostered a collaborative, partnership approach in the region to implement sustainable coastal and ocean development of these LMEs. ICM provided the foundational delivery system promoting interdisciplinary approaches and cooperation among users and beneficiaries to address complex development issues. While addressing marine pollution at the beginning, it became obvious that it had to be tackled in the context of the whole marine environment and sustainable development. PEMSEA developed and adopted the Sustainable Development Strategy for the Seas of East Asia (SDS-SEA) as the regional policy instrument from which countries of the region and other partners, individually or in groups, could apply the action programmes relevant to them. This in-depth review article describes the evolution of PEMSEA from a regional marine pollution project to an international organization, highlighting key developments, such as the SDS-SEA, the ICM Code, and the Ocean Investment Service, as well the advancement of ICM throughout the East Asian region and the adoption of the State of Oceans and Coasts reporting system to track progress. Looking forward, we summarize a United Nations Environment and IOC-UNESCO assessment of the current baseline status of these East Asian LMEs to examine future key areas for intervention by PEMSEA.
The history of commercial exploitation of fish stocks is replete with instances of over-exploitation and stock collapse. Particularly in situations where little is known about a species or a particular fish stock, unregulated expansion into new fisheries may effectively wipe out a species or stock before its existence is even formally recognised or understood. Globally, there has been a strong interest in ensuring that such a fate does not befall any fish stocks that either exist in or may migrate in future into the high seas portion of the Central Arctic Ocean. The Agreement to Prevent Unregulated High Seas Fisheries in the Central Arctic Ocean establishes a framework for the acquisition of science upon which precautionary, ecosystem-based management measures can be based, if and when they become necessary in the future. This article examines the role of international law in facilitating both the adoption of the Agreement and the adaptive management of fisheries in the high seas portion of the Central Arctic Ocean. It will be shown that the Agreement provides the initial framework for precautionary, ecosystem-based, adaptive and environmentally sound decision making regarding potential future fisheries in the Central Arctic Ocean.
- The relative availability of alternative organic matter sources directly influences trophic interactions within ecological communities. As differences in trophic ecology can alter the productivity of communities, understanding spatial variability in trophic structure, and the drivers of variability, is vital for implementing effective ecosystem‐based management.
- Bulk stable isotope analysis (δ13C and δ15N) and mass balance calculations were used to examine patterns in the contribution of organic matter derived from macroalgae to food webs supporting temperate reef fish communities in two contrasting coastal waterways on the South Island of New Zealand: Fiordland and the Marlborough Sounds. Ten fish species common to both regions were compared, with up to 40% less organic matter from macroalgae supporting omnivorous species in the Marlborough Sounds. The largest differences in trophic position were found in those species exploited by fisheries.
- Furthermore, stratified surveys of abundance and species biomass combined with trophic position data were used to calculate regional differences in the contribution of macroalgae to whole fish communities in terms of density of biomass. In Fiordland, over 77% of the biomass of exploited reef fishes was supported by macroalgae, compared with 31% in the Marlborough Sounds.
- Surveys of macroalgal density and species composition in the two regions indicated that regional differences in trophodynamics may be explained by a lack of macroalgal inputs to the food web in the Marlborough Sounds.
- The findings demonstrate large regional differences in the incorporation of benthic and pelagic sources of organic matter to food webs supporting reef fish communities, highlighting the need for ecosystem‐based approaches to management to recognize spatial variability in primary production supporting coastal food webs.
The need for management approaches based on ecosystem perspectives that thoroughly incorporate ecosystem considerations into marine planning has become increasingly urgent. In response, concepts such as ecosystem-based management (EBM), ecosystem-based approach (EBA) and ecosystem approach (EA) are increasingly being applied in marine/maritime spatial planning (MSP). The purpose of this article is to clarify potential differences and similarities between the three concepts and potential consequences of choosing one over the others. From a questionnaire and literature analysis, the findings showed vast disagreements on how the concepts are related, however the main perception is that the concepts overlap. Respondents agreed that a lack of clear definitions and understandings of the three concepts causes confusion and expect negative consequences for planning outcomes. Eleven principles for how the concepts are ideally performed were found, including; acknowledge interlinkages, see humans as a part of the ecosystem and consider cumulative impacts. While a complete overlap between EBM and EA principles were found, the weighting of each principle was different for each concept. Differences were also found in objectives of the concepts, where definitions of EBM were the only ones to include the objective of co-existence and definitions of EBA the only to include objectives of impact management and good environmental status. As this could have consequences in planning processes and thus in the outcomes, it is crucial that MSP practitioners and stakeholders are aware of different perceptions so that choosing between concepts does not lead to less ambitious or inadequate outcomes.
Primary considerations for adopting an ecosystem approach to fisheries management (EAFM) as a management approach will involve an expanded scope of fisheries management over conventional approaches; specifically, EAFM will involve a broader scale of management. Development of a sub-regional EAFM plan can complement local, national, and regional fisheries management priorities, as well as help to catalyze management action at multiple levels that may not otherwise occur. A sub-regional EAFM policy planning approach has been undertaken for the Sulu-Sulawesi Seascape (SSS), a sub-region of Southeast Asia. This sub-regional policy planning approach illustrates how “scaling up” EAFM can support relevant international, regional, and other sub-regional fisheries management plans and environmental initiatives, while “scaling down” EAF can support relevant national, provincial/state, and local fisheries management plans in Indonesia, Malaysia and the Philippines.
There is growing empirical evidence around the world demonstrating regime shifts of marine ecosystems. But generalizable criteria to detect and define regime shifts are elusive because of: (i) an incomplete scientific understanding of processes underlying regime shifts; (ii) because the baseline state and conditions are ill defined, and; (iii) due to an inherent ambiguity in the concept of system identity. We surveyed marine scientists in Tasmania, Australia, and determined the effect of changing conditions (including type of climate impact, species loss, species composition, spatio-temporal extent, and human intervention) on their perception of marine regime shift. We find, there is an objective difficulty in detecting regime shifts that goes beyond scientific uncertainty and there is disagreement on which configurations of change indeed constitute a regime shift. Furthermore, this difference of opinion was not related to the degree of confidence that scientists indicated when identifying regime shifts. This lack of consensus and seemingly unrelated scientific confidence, may be attributable to value ambiguity around people s attitudes, cognitive biases, and baseline shift. When applying evidenced-based reference points in well-reasoned Ecosystem Based Management, there should be scientific consensus on the manifestation and extent of specific regime shifts, and recognition of value ambiguities influencing scientific perceptions.
Change is inherent in coastal systems, which are amongst the most dynamic ones on Earth. Increasing anthropogenic pressure on coastal zones interferes with natural coastal dynamics and can cause ecosystem imbalances that render the zones less stable. Furthermore, human occupation of coastal zones often requires an uncharacteristic degree of stability for these inherently dynamic coastal systems. Coastal management teams face multifaceted challenges in protecting, rehabilitating and conserving coastal systems. Diverse monitoring schemes and modelling tools have been developed to address these challenges. In this article, we explore various perspectives: the integration of biophysical, ecological and social components; the uncertainties of diverse data sources; and the development of flexible coastal interventions. We propose general criteria and guidance for an Ecosystem-based Management (EbM) to coastal management, which aims primarily at adaptation to global change and uncertainties, and to managing and integrating social aspects and biophysical components based on the flows of energy and matter.