Escapes and Introductions
Escapees from aquaculture facilities can potentially impact on habitats and species in the receiving water bodies. Problems could occur due to: competition; potential disease transfer; establishment of non-native species; interbreeding with wild populations; and impacts on sensitive habitats. Vietnam continues to be at the centre of production and escapes of pangasius within its native range (i.e. the Mekong river) is not considered a major concern1. However pangasius is now farmed in parts of the world as a non–native species, with large-scale production in countries such as Bangladesh2, 3 and India alongside a developing small-scale production level in regions such as the Caribbean.
The contribution of non-native species to the growth of the global aquaculture industry and the economic benefits that it has brought to many countries cannot be underestimated. However, minimising the escapes of non-native aquaculture species must be a high priority for resource managers, conservationists and the aquaculture industry4.
Authorities can ensure that new pangasius facilities apply for the appropriate licences and permits, and should provide evidence that containment systems will prevent escape and escapees will not establish in the wild.
Losses due to escapes represent a considerable financial loss to a farm so it is in their interest to prevent them as much as possible. There has been increasing regulation, uptake of Best Management Practices (BMPs), codes of conduct or practices and certification schemes in pangasius aquaculture which help in tackling escape issues.
To reduce escape risks farms should have trapping devices such as screens and grills on all water inlets, outlets and drainage channels; these should be suitably sized to match the size of the stock. These screens should be regularly inspected, maintained and such actions recorded. Pond embankments, bunds, and levees should be of adequate height and build standard to retain stocks during periods of flood and regularly inspected and maintained. There should be no intentional release of pangasius stock from the farm.
Pangasius broodstock or juveniles should be from trusted and registered sources, disease free, and have met all appropriate legal requirements and guidelines.
- Seafood Watch
- Singh, A.K. and Lakra, W.S., 2012. Culture of Pangasianodon hypophthalmus into India: Impacts and Present Scenario. Pakistan Journal of Biological Sciences, 2012, 15 (1) p19-26
- Ali, H. et al, 2013. Striped catﬁsh (Pangasianodon hypophthalmus, Sauvage, 1878) aquaculture in Bangladesh: an overview. Aquaculture Research, 2013, 44, p950–965
- Cook, E.J. et al, 2007. Non-Native Aquaculture Species Releases: Implications for Aquatic. Chapter 5 in Aquaculture in the Ecosystem, p155-184