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Aquaculture and selective breeding have produced unique strains of fish tailored for efficient farming. While controversial, these man-made fish now make up a major part of seafood production.
Here are 8 of the most common man-made fish species that end up on our plates.
1. Tilapia
Arguably the most popular farm-raised fish, modern tilapia strains are the product of decades of selective breeding. The most famous example is the GIFT strain (Genetically Improved Farmed Tilapia) developed in the late 1980s to have superior traits like faster growth and disease resistance.
Other hybrids like the Rocky Mountain White are a cross between different tilapia species. These man-made fish now account for 5.5 million tonnes of annual tilapia production.
2. Atlantic Salmon
Atlantic salmon grown on fish farms are domesticated variants selectively bred over decades for aquaculture. However, a genetically engineered AquAdvantage salmon also exists which grows twice as fast as wild salmon. It was approved for sale in the U.S. and Canada in 2015. Critics argue it poses risks like accidental release into the wild.
3. Rainbow Trout
Rainbow trout farmed for food are hatchery-raised specifically for traits like faster growth and the ability to thrive at high densities. They are bred to grow much faster and tolerate stressful conditions that wild trout cannot. However, studies show they have less omega-3s compared to wild trout.
4. Catfish
Like tilapia, catfish sold commercially are not wild but rather domesticated hybrids optimized for farming. Channel catfish and blue catfish are selectively bred for rapid growth, disease resistance, and meat yield. Global catfish production exceeded 5 million metric tons in 2020.
5. Striped Bass
A hybrid striped bass known as the “palmetto bass” is now widely farmed in the U.S. It is produced by crossing female white bass with male striped bass. Though not currently genetically engineered, they are bred to reach harvest size quicker than wild striped bass.
6. Flounder
In Asia, flounder aquaculture relies on variants created through selective breeding like the Japanese flounder. Scientists are also working on manipulating genes to produce faster-growing flounder with more muscle mass to boost meat yield.
7. Coho Salmon
Selective breeding programs produce most farmed coho salmon. However, the biotech company AquaBounty has also developed a genetically engineered coho salmon that grows up to six times faster than wild salmon. It is pending approval for commercial use.
8. Common Carp
Though seldom farmed in North America, common carp dominate aquaculture in China. Chinese researchers are using selective breeding and genetic manipulation techniques to develop improved carp strains that grow faster while tolerating crowded conditions.
Conclusion
From GMO salmon to hybrid catfish, a variety of engineered and selectively bred fish now supply most of the seafood we eat. Supporters argue this is vital for meeting rising demand and feeding the planet.
Critics counter that modifying fish genetics poses risks. One thing is clear – aquaculture is increasingly turning to man-made fish.
There are still plenty of naturally wild-caught fish species to enjoy. Understanding the source of our food empowers us to make informed choices.
