Feisty Hybrid Fish
Overfishing is a massive environmental threat – if left unchecked, it could deplete the marine ecosystem and jeopardise the food security of more than a billion people for whom fish is a primary source of protein. To this end, genetically modified (GM) hybrid fish species are being developed to boost diminishing fish stocks. However, new findings have revealed that these ‘super’ species can present new challenges.
A recent study from scientists at Canada’s Memorial University of Newfoundland – conducted in a simulated stream – found that the hybrid offspring of GM salmon and wild brown trout grow faster than their parents and are more competitive food scourers. In fact, the aggressive hybrid fish suppressed the growth of genetically modified salmon by 82% and wild salmon by 54% when competing for nourishment.
"To the best of our knowledge, this is the first demonstration of environmental impacts of hybridisation between a GM animal and a closely related species," the study concluded. "These findings suggest that complex competitive interactions associated with transgenesis and hybridisation could have substantial ecological consequences for wild Atlantic salmon should they ever come into contact [with GM salmon] in nature."
US biotechnology firm AquaBounty, which is engineering advanced hybrids (salmon, trout and tilapia) for human consumption, claim any risks are negligible as the fish they were producing were all female, sterile, and would be housed in tanks on land.
The US Food and Drug Administration is still deciding whether GM salmon will be commercially retailed in the US.
For more on how fisheries, seafood brands and scientists are working to solve the issue of overfishing and consumer awareness and concern, see Stylus’ Social Seafood report and Project Ocean, Selfridges: Retail Activism in Action.