Aquaculture can contribute to biodiversity and habitat loss in freshwater and marine ecosystems, but when used wisely, it can also be part of the solution.

Published today in Conservation Biology, our new paper Achieving conservation and restoration outcomes through ecologically beneficial aquaculture (full open access at: identifies 12 ecological benefits of aquaculture. These include species recovery, habitat restoration, rehabilitation and protection, and removal of overabundant species.

Millions of tonnes of fish, shrimp, shellfish and seaweed are farmed for food each year, with some of this industrial production benefitting the environment when farmed in a specific way or place. For example, seaweed and shellfish farmed in coastal waters remove excess nutrients from urban or agricultural runoff and reduce toxic algal blooms that kill fish and other organisms.

In addition, conservationists tap into aquaculture techniques to create new ways to restore or conserve species and habitats. The world’s largest conservation organisation, The Nature Conservancy, has pioneered the use of aquaculture to restore lost marine ecosystems. Aquaculture is a key part of the process to rebuild lost shellfish reefs through creating healthy oyster and mussel juveniles to kick start reef restoration.

Aquaculture is also used to help restore endangered fish populations by ‘restocking’ cultured fish back into their habitats. Species recovery programs for white sturgeon in North America, golden mahseer in India, and Macquarie perch in Australia, are trying to bring back wild populations from the brink of extinction.

In some instances, aquaculture can replace fishing. Most freshwater aquarium species are farmed, which means you can stock your aquarium without taking fish from the wild. But many species in marine aquariums, like clownfish and corals, are collected from coral reefs. Many people are trying to farm these desirable species, to ease pressure on wild populations.

Our work also recommends using measurable indicators of success. Requiring a high standard of evidence to label something ‘ecologically beneficial’ reduces potential for ‘greenwashing’, where aquaculture industries might claim to be providing ecological benefits that aren’t really there. We want to ensure that aquaculture practitioners monitor their ecological impact before claiming their farm creates ecological benefits. It is important to weigh up overall impacts when deciding if something is ecologically beneficial or not.

As aquaculture expands, we see an opportunity to avoid the mistakes resulting from  farming on land that cause habitat and biodiversity loss. We want people to reimagine what aquaculture can do and show people how, when used wisely, it can be a tool to safeguard ecosystems and biodiversity.



By Tim Dempster