How aquatic biodiversity will be key to a food secure world

Editor/Mohamed shihab

Expanding sustainable aquaculture will be key to meeting the ever-increasing demand for aquatic food in the future. The way that aquatic genetic resources (AqGR) are managed, developed and applied in aquaculture, is critical for productivity and sustainability as the sector grows.

Graham Mair, senior aquaculture officer at FAO, discusses some of the challenges and opportunities for enhancing the sustainable development of this fast-changing sector.

What are aquatic genetic resources?

Aquatic genetic resources refer to all species used in aquaculture and their wild relatives, and also incorporates DNA, genes, chromosomes and tissues. We currently farm almost 700 aquatic species including finfish, molluscs, crustaceans, macro and microalgae and plants.

FAO's regular production reporting has information related to most cultured species but not enough details about what's being farmed, and particularly about the strains and varieties (known as farmed types) within these species.

We are still very early in developing aquaculture. Most of the species we culture were domesticated in the last 50 to 60 years, compared to terrestrial animals and plants which were domesticated 5,000 to 10,000 years ago and this represents a major opportunity as today's farmed AqGR still retain most of the genetic variation present in the wild.

What are the challenges in managing genetic aquatic resources?

In the absence of reliable information about our aquatic genetic resources, it becomes very difficult to develop strategies for their effective management.

SDG target 2.5 is committed to "maintain the genetic diversity of seeds, cultivated plants and farmed and domesticated animals and their related wild species". But without adequate monitoring, it is difficult to meet the SDGs or to halt and reverse biodiversity loss.

One of FAO's priorities is to try to bridge the gap where there is no registered information. The State of the World's Aquatic Genetic Resources for Food and Agriculture Report is the first global assessment of the status of genetic resources. FAO has also developed AquaGRIS, a global information system of aquatic genetic resources that countries can use to create registries of their important AqGR (both species and farmed types), which can support future strategic planning and make information available to a range of stakeholders.

How important is genetic management for the future of biodiversity conservation and aquaculture?

The good news is that all aquatic species that we farm still exist in the wild. You cannot say that for crops or livestock. For livestock there are only five major species that we farm, and the forerunner of domestic cattle doesn't even exist in the wild anymore. Since our species have only recently been domesticated, they still have most of the genetic variation that you would find in the wild. Because of these high levels of genetic diversity, when we apply traditional selective breeding, we can generate gains in commercially important traits of 12-13 percent per generation, compared to typical improvement rates of 1-2 percent in crops and 2-4 percent in livestock.

There are many genetic technologies we can apply to aquatic species but as aquaculture is still relatively new, we do not yet have sufficient knowledge about the genetics of the species we farm. In developing a new species for aquaculture, you might work out how to breed it and begin to farm it, but without effective genetic management, you can quickly see a deterioration in performance because of problems such as inbreeding or unwanted hybrid introgression. So, we really need to build awareness about the importance of conserving our genetic resources in the wild, applying best practices of genetic management to our domesticated farmed types and to take advantage of the opportunities we have for genetic improvement.

How is FAO responding to the challenges?

The Global Plan of Action for the Conservation, Sustainable Use and Development of Aquatic Genetic Resources for Food and Aquaculture (GPA) was developed by FAO at the request of the members of the Commission on Genetic Resources for Food and Agriculture.

The GPA has four priorities. The first is information. We can't plan effectively if we don't know what AqGR we have. The global assessment and AquaGRIS are valuable resources that can make a difference.

The second component is conservation and sustainable use. Aquatic species must be conserved, so we don't lose this important reservoir of genetic diversity for the future. It's important to recognize there are some species that are very common in aquaculture, like the common carp, are already classified by IUCN as being under threat in the wild.

The third component is the development of AqGR because we are so far behind other agricultural sectors in the development of our resources. In terrestrial agriculture almost everything we consume has been genetically improved. For aquaculture, it's estimated that only 10-15 percent of cultured aquatic food is from improved farmed types.

So, we need to focus efforts on accelerating the adoption of basic selective breeding because there are considerable opportunities. We have all this genetic variation to exploit and we can get these spectacular gains from genetic improvement so we should be doing more of it. We are starting to do it slowly, and mainly for our higher value species based in the developed world, but we need to find a way to do this for the lower value species that are most important for global food security, and that's not really happening.

The final component of the GPA is about ensuring policies, institutions and capacity building deliver on the first three priority areas. It's about getting the policymakers to create the right environment for effective management of aquatic genetic resources and making sure we have the institutions and trained personnel to support the development of long-term breeding programmes.

The adoption of the GPA is a critical step. It offers options for action based on the status of AqGR in a country. FAO now stands ready to engage and support countries in planning and implementing the GPA relevant to their specific priorities.