Is the neon green tetra GloFish soon to be the florescent, transgenic terror of America's waterways? The internet hype machine has repeated ad infinitum the Washington Post's recent story about the invasive potential of a new breed of GloFish. First sold to the public in 2003, the original GloFish were four brightly colored strains of zebrafish that fluoresced thanks to jellyfish and coral genes.

Last February, the biotech company Yorktown expanded their species range by introducing a transgenic, acid green version of the tetra fish. It's this Electric Green Tetra (©) that has biologists and wetland conservationists worried. While tropical zebrafish go belly-up in cooler US waters, their argument goes, tetras are better adapted to seasonally cold conditions. Any released GloFish tetras could potentially take over lakes and rivers, their freaky genes compelling them to outcompete native species or breed with their wild cousins.

It's a catchy argument. It's also untrue.

Although it's easy to discredit corporate shills, the chief executive of Yorktown has a good point: "The black tetra has been sold for over 60 years and there has never been an ecological concern with it." Color aside, the Electric Green Tetra is no different from this pet store standard. In fact, the copyrighted fish may be ill-suited to life outside the tank. While the wild version sports silver and black stripes, the GloFish tetra is a brilliant, day-glo green.

What makes GloFish highly attractive to humans is also what makes them highly visible to predators. Neon red zebrafish, for instance, are twice as likely to be eaten by largemouth bass as their wild-type counterparts. If any escapees are left after predators get to them, it seems likely that wild tetras would be unlikely to recognize a GloFish as a fellow species member. Offspring that express the green florescent protein would quickly be weeded from the population.

The hand-wringing over GloFish typifies our schizophrenic attitude towards technological change. Any new technology, especially one that tinkers with our notions of "natural" and "unnatural" is automatically viewed as dangerous. As the first GM organism available as a pet, GloFish have inspired their fair share of anger and debate. They're still banned in California and in the European Union, places where the wild-type black tetra is perfectly legal. While keeping a South American fish in a New Jersey living room is "natural", it's eerie, even frightening, to think of white-coated scientists fiddling with the genes of those same fish.

The largest burmese python caught in Florida was 17.7 feet long. Stuffed with 87 eggs, it was like all Florida pythons the descendent of released or escaped pets.

The all-natural exotic animal trade has proved far more devastating than any batch of maladapted transgenic fish. The estimated 10,000 to 30,000 Burmese pythons living in Florida, all descended from escaped pets, are now making a smorgasbord of the state's endangered mammals, birds and reptiles. Lionfish, a popular aquarium species that hails from Southeast Asia, are so voracious that they are now the sole inhabitants of some reefs in the Caribbean. Yet exotic pets do not receive the kind of knee-jerk fear that GMOs do. We've sending animals around the world for centuries. The exotic animal trade is so normalized that it's mostly invisible.

No one is rallying to ban home aquariums filled with fish from the Amazon, from Lake Victoria, or from the South China Sea. At the same time, conservationists and the general public condemn neon fish for their imagined threat to the natural order. Clearly, we're not advocating a free-for-all adoption of every GM organism. Instead, we must follow a science-based approach that doesn't ban new technologies simply because they make us feel funny.

Now, time to switch on the blacklight and prepare some delicious GloFish sushi.

Lionfish hunting efforts, while commendable, aren't doing much to dent their populations. They have spread from the Caribbean as far north as the Carolinas.

Images via Aquatic CommunityPalm Beach Post and National Geographic.

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  • All good points. Might I also add that I rarely ever hear fishermen complain about falsely stocked ponds for competitions. One quarter of our states have experiences ecosystem issues in lakes and ponds with fish improperly stocked for what can only be considered canned fishing. Nice article!

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