Projecting global mariculture diversity under climate change

Previous studies have focused on changes in the geographical distribution of terrestrial biomes and species targeted by marine capture fisheries due to climate change impacts. Given mariculture’s substantial contribution to global seafood production and its growing significance in recent decades, it is essential to evaluate the effects of climate change on mariculture and their socio‐economic consequences. Here, we projected climate change impacts on the marine aquaculture diversity for 85 of the currently most commonly farmed fish and invertebrate species in the world’s coastal and/or open ocean areas. Results of ensemble projections from three Earth system models and three species distribution models show that climate change may lead to a substantial redistribution of mariculture species richness potential, with an average of 10%–40% decline in the number of species being potentially suitable to be farmed in tropical to subtropical regions. In contrast, mariculture species richness potential is projected to increase by about 40% at higher latitudes under the ‘no mitigation policy’ scenario (RCP 8.5) by the mid‐21st century. In Exclusive Economic Zones where mariculture is currently undertaken, we projected an average future decline of 1.3% and 5% in mariculture species richness potential under RCP 2.6 (‘strong mitigation’) and RCP 8.5 scenarios, respectively, by the 2050s relative to the 2000s. Our findings highlight the opportunities and challenges for climate adaptation in the mariculture sector through the redistribution of farmed species and expansion of mariculture locations. Our results can help inform adaptation planning and governance mechanisms to minimize local environmental impacts and potential conflicts with other marine and coastal sectors in the future.

Sustainable aquaculture in Canada: Lost in translation

his paper examined the SI used by the Canadian government to assess the social, economic and environmental sustainability of aquaculture production in Canada, whether they adequately measure policy outcomes, and whether national-level SI indicators are appropriate to assessing sustainability at the community-level.

Potential impacts of finfish aquaculture on eelgrass (Zostera marina) beds and possible monitoring metrics for management: a case study in Atlantic Canada

Eelgrass (Zostera marina) has been designated an Ecologically Significant Species in Atlantic Canada. The development and rapid expansion of netpen finfish aquaculture into sensitive coastal habitats has raised concerns about the impacts of finfish aquaculture on eelgrass habitats. To date, no studies have been done in Atlantic Canada to examine these impacts or to identify potential monitoring variables that would aid in the development of specific conservation and management objectives. As a first step in addressing this gap, we examined differences in environmental variables, eelgrass bed structure and macroinfauna communities at increasing distances from a finfish farm in Port Mouton Bay, a reference site in adjacent Port Joli Bay, and published survey results from other sites without finfish farms along the Atlantic Coast of Nova Scotia. Drawing on research done elsewhere and our results, we then identified possible metrics for assessing and monitoring local impacts of finfish aquaculture on eelgrass habitats. Our results suggest some nutrient and organic enrichment, higher epiphyte loads, lower eelgrass cover and biomass, and lower macroinfauna biomass closer to the farm. Moreover, community structure significantly differed between sites with some species increasing and others decreasing closer to the farm. Changes in the macroinfauna community could be linked to observed differences in environmental and eelgrass bed variables. These results provide new insights into the potential impacts of finfish aquaculture on eelgrass habitats in Atlantic Canada. We recommend a suite of measures for assessment and monitoring that take into account response time to disturbance and account for different levels of eelgrass organizational response (from physiological to community).

Aquaculture law and policy: global, regional and national perspectives.

With aquaculture operations fast expanding around the world, the adequacy of aquaculture-related laws and policies has become a hot topic. This much-needed book provides a comprehensive guide to the complex regulatory seascape. Split into three distinct parts, the expert contributors first review the international legal dimensions, including chapters on the law of the sea, trade, and access and benefit sharing for aquatic genetic resources. Part Two discusses how the EU and regional bodies, such as the North Atlantic Salmon Conservation Organization (NASCO), have addressed aquaculture development and management whilst the final part contains twelve national case studies exploring how leading aquaculture producing countries have been putting sustainability principles into practice. These case studies focus on implementation approaches and challenges, in particular emphasizing ongoing national struggles in attaining effective aquaculture zoning and marine spatial planning. Students and scholars of environmental law and politics will find this contemporary volume an invaluable addition to the limited academic literature critiquing aquaculture law and policy. Policy makers, international bodies and NGOs will also find its insights particularly informative when ensuring sustainable aquaculture regulation and development.

Observed and projected impacts of climate change on marine fisheries, aquaculture, coastal tourism, and human health: an update.

The Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) states that climate change and ocean acidification are altering the oceans at a rate that is unprecedented compared with the recent past, leading to multifaceted impacts on marine ecosystems, associated goods and services, and human societies. AR5 underlined key uncertainties that remain regarding how synergistic changes in the ocean are likely to affect human systems, and how humans are likely to respond to these events. As climate change research has accelerated rapidly following AR5, an updated synthesis of available knowledge is necessary to identify emerging evidence, and to thereby better inform policy discussions. This paper reviews the literature to capture corroborating, conflicting, and novel findings published following the cut-off date for contribution to AR5.

Fishing for the future: an overview of challenges and opportunities.

This paper surveys the current state and major trends in global fisheries; the environmental and social dimensions of fisheries; and explains how the international community has tried to meet the policy challenges associated with oceans and fisheries. The ocean and the freshwater ecosystems of the world make significant contributions to people’s well-being via the many vital social and environmental services they provide (for example, food and nutrition, employment and incomes, carbon cycling and sequestration). The impact that the increase in fishing since the 1950s has had on wild fish stocks, and the significant increase in aquaculture production in the 20th century, have resulted in severe environmental impacts. This has significant effects on marine ecosystems and the health of oceans. The erosion of the resource undermines communities’ long-term interests, including food security, employment, and income. Attempts by the global community to address challenges of sustainable production by improving the governance and management of fisheries resources range from national management of fisheries resources, to regional fisheries management organisations (RFMOs) for international fisheries stocks. These attempts have not always successfully met the challenge of balancing current and future use of fisheries.

Boom or bust: the future of fish in the South China Sea.

Asia’s oceans are home to some of the richest and most diverse fisheries in the world and the South China Sea (SCS) is no exception. Its fish resources are crucial for food security, supporting coastal livelihoods and export trade, yet they are threatened by pollution, coastal habitat modification and excessive and destructive fishing practices. In 2015 the University of British Columbia Fisheries Economic Research Unit and Changing Ocean Research Unit undertook to outline the threats to the SCS and determine what its marine ecosystems, fisheries and seafood supply may look like in the next 30 years under different climate change and management scenarios.

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