Seaweed aquaculture accounts for 51.3% of global mariculture production and grows at 6.2% yr−1 (2000–2018). It delivers a broad range of ecosystem services, providing a source of food and natural products across a range of industries. It also offers a versatile, nature-based solution for climate change mitigation and adaptation and for counteracting eutrophication and biodiversity crisis. Here we offer the perspective that scaling up seaweed aquaculture as an emission capture and utilization technology, one supporting a circular bioeconomy, is an imperative to accommodate more than 9 billion people in 2050 while advancing across many of the United Nations Sustainable Development Goals. Agriculture’s ability to feed the world is limited by land and freshwater. This Perspective argues that scaling up seaweed aquaculture is needed to accommodate the 9+ billion people expected by 2050 and to meet the Sustainable Development Goals.

A seaweed aquaculture imperative to meet global sustainability targets

The farming of the red seaweed Kappaphycus alvarezii and related species as raw material
for the hydrocolloid carrageenan rapidly spread from the Philippines in the late 1960s to Indonesia,
Tanzania, and other tropical countries around the world. Although numerous studies have
documented positive socioeconomic impacts for seaweed farming, factors such as diseases and
distance to export markets have led to an uneven development of the industry. Using standard
budgeting techniques, this study adapted production and market data from a FAO-led global
review of seaweed farming to develop comparative enterprise budgets for eight farming systems in
six countries (Indonesia, the Philippines, Tanzania, India, Solomon Islands, and Mexico).
Although the basic technology package is the same across countries, the study revealed large
differences in the economic performance of systems due to wide variations in farm prices and the
scale of operations. Although seaweed farming is a suitable activity for small-scale producers, a
minimum of 2,000m of cultures lines are still necessary to ensure adequate economic returns.
Greater farming plots may be needed if farm prices are well below the average farm prices paid
in Indonesia and the Philippines. Policy recommendations are made to improve the economic
potential of underperforming systems.

The Economics of Kappaphycus SeaweedCultivation in Developing Countries: AComparative Analysis of Farming Systems

Hatchery management of tiger grouper (Epinephelus fuscoguttatus): a best-practice manual.

Leopard coral groupers belong to the Plectropomus genus of the Epinephelidae family and are important fish for coral reef ecosystems and the marine aquaculture industry. To promote future research of this species, a high-quality chromosome-level genome was assembled using PacBio sequencing and Hi-C technology. A 787.06 Mb genome was assembled, with 99.7% (784.57 Mb) of bases anchored to 24 chromosomes. The leopard coral grouper genome size was smaller than that of other groupers, which may be related to its ancient status among grouper species. A total of 22 317 protein-coding genes were predicted. This high-quality genome of the leopard coral grouper is the first genomic resource for Plectropomus and should provide a pivotal genetic foundation for further research. Phylogenetic analysis of the leopard coral grouper and 12 other fish species showed that this fish is closely related to the brown-marbled grouper. Expanded genes in the leopard coral grouper genome were mainly associated with immune response and movement ability, which may be related to the adaptive evolution of this species to its habitat. In addition, we also identified differentially expressed genes (DEGs) associated with carotenoid metabolism between red and brown-colored leopard coral groupers. These genes may play roles in skin color decision by regulating carotenoid content in these groupers.

Whole-genome sequencing of leopard coral grouper ( Plectropomus leopardus) and exploration of regulation mechanism of skin color and adaptive evolution.

Genome resequencing of the orange-spotted grouper (Epinephelus coioides) for a genome-wide association study on ammonia tolerance

Aquaculture of groupers is carried out in tropical and subtropical areas throughout the world, but most production is from Asia, with three countries responsible for an estimated 92% of global production: China (65% of total production), Taiwan Province of China (17%) and Indonesia (11%). We calculate that there are at least 47 grouper species plus 15 grouper hybrids that have been trialled or are currently aquacultured. While grouper aquaculture has undoubtedly provided positive social and economic benefits to coastal communities in Asia, practices associated with grouper aquaculture have also led to widespread concerns regarding its environmental impacts. This paper reviews environmental, economic and social impacts of grouper aquaculture within a sustainability science framework. An update, building on early technical reviews of grouper aquaculture, was used to identify the main environmental, economic and social impacts. The main environmental impacts identified were as follows: seedstock sources, particularly the use of wild-caught postlarval or juvenile fish as seedstock; the use of 'trash' fish as the major feed source; and water quality and substrate impacts of sea cage aquaculture. Significant economic and social impacts arising from grouper aquaculture include employment and income generation, but the economic impacts of disease outbreaks are significant, reducing fish survival to harvest size to around 50-70%. Current approaches to ameliorate negative impacts include the following: development and implementation of better management practices (BMPs) at national level, and the development of a global ecolabel certification scheme by the Aquaculture Stewardship Council. Both these approaches have significant constraints, particularly when applied to small-scale farmers who produce the bulk of farmed grouper. We conclude that there is a need for improved higher level coordination between the major producer countries to address identified sustainability constraints to grouper aquaculture. © 2017 Wiley Publishing Asia Pty Ltd.

Michael A. Rimmer

Papers

A review of grouper (Family Serranidae: Subfamily Epinephelinae) aquaculture from a sustainability science perspective

Women's well-being and household benefits from seaweed farming in Indonesia

Meta-analysis of the use of seaweeds and their extracts as immunostimulants for fish: a systematic review

Nursery management of grouper: a best-practice manual.

Seaweed dietary supplements enhance the innate immune response of the mottled rabbitfish, Siganus fuscescens.