Rationale 2.4

The introduction of non-native (or alien) species, often driven by human activities, poses significant concerns for natural ecosystems. Their impacts can vary widely, from negligible effects to severe ecological disruptions. These consequences often emerge after extended periods and can vary significantly based on the biological traits of the species and the characteristics of the receiving ecosystem2626Blackburn, T. M., Essl, F., Evans, T., Hulme, P. E., Jeschke, J. M., Kühn, I., … & Bacher, S. (2014). A unified classification of alien species based on the magnitude of their environmental impacts. PLoS biology, 12(5), e1001850. https://doi.org/10.1371/journal.pbio.1001850.

The global aquaculture industry is a key contributor to the spread of alien species. Many of these species have escaped into the wild, establishing populations that can cause ecological harm. Risks to native biodiversity may also arise where farmed animals become reproductively mature and spawn in culture systems, creating a risk of genetic interaction, hybridisation or introgression with wild populations, even where no physical escape of live animals is confirmed. This underscores the need for effective management strategies and scientifically sound evaluation tools.

To address these challenges, the International Union for Conservation of Nature (IUCN) developed the Environmental Impact Classification for Alien Taxa2727International Union for Conservation of Nature (IUCN). (2020). IUCN EICAT Categories and Criteria. The Environmental Impact Classification for Alien Taxa. Gland, Switzerland and Cambridge, UK: IUCN. https://doi.org/10.2305/IUCN.CH.2020.05.en (EICAT). EICAT is a globally recognised framework that classifies alien species based on the magnitude and mechanisms of their environmental impact. It provides a transparent basis for identifying and prioritising species of concern and for informing appropriate management responses. ASC conducts EICAT assessments and makes the outcomes publicly available.

ASC-certified farms are required to implement robust escape management practices and mitigation measures aligned with the relevant EICAT classification(s), where applicable, to minimise the risks posed by alien species and their impacts.

Intent – The aquaculture industry cultivates species in a manner that poses minimal risk to native biodiversity.