Escape From The Alcatraz Of Aquaculture: How Fish Farm Escapees Are Changing The Ecosystem Permanently
No matter how many times humanity is taught certain lessons we never really seem to learn. Our history abounds with examples where we tried to control or alter the delicate balance of nature to better benefit humankind, for example the introduction of the mongoose to the Hawaiian islands at the height of the plantation era in the mid 1800s, ostensibly to kill the native tree rats that threatened the sugarcane and the profits of the planter class.
Of course, the people behind this scheme neglected to note that the rats are nocturnal, while the mongoose is diurnal, so they didn’t’ cross paths often enough for to make a difference in the rat population. However native birds and their eggs proved a tasty treat for the mongoose. They are still a nuisance species there to this day.
Fast forward to modern methods and modern technology and you can imagine how much more severe the unintended consequences can be when the designs of men trying to play god go wrong, as they nearly always do. Modern aquaculture is a prime example.
The complications of course are multiplied exponentially given the fact that these ‘farms’ exist in the open ocean; when you see photos of their flimsy looking pens and fencing against the backdrop of the vastness of the sea, you get some notion of just how precarious the practice really is.
One recent example is the discovery of a fish called the cobia in the eastern Pacific following the escape of some 1500 fish from a farm in Ecuador. The speedy, aggressive predator can grow up to two meters long, and since the jailbreak has been spotted from Panama to Peru.
The cobia story is not an isolated event. Up to a third of all modern aquaculture takes place off shore, where pens are subject to damage from storms, predators, thieves and human error. And with some 25 million metric tons of fish being farmed every year, the potential for damage to native species is immense.
The cobia example, one in which a non-native predator escapes and can potentially wreak havoc on native prey species is only the most demonstrable type of change we can observe.
But even if the fish and mollusks being raised is native to the area, when weaker, antibiotic-riddled farm fish mate with their wild cousins, they weaken and otherwise alter the genetic line of the animals.
And while its hard to quantify just how many farmed fish escape, some studies put the number at a staggering nine million individuals per year. It is almost literally unimaginable to try to figure out what changes so many genetically and medically altered fish are wreaking on their wild cousins.
From poisonous cane toads overrunning native species in Australia to a Texas experiment with fire ants that went awry, we can see that the damage we do to nature whenever we mess with it is incalculable. And with farmed fish the damage is just starting to become apparent: in Chile a few months ago heavily medicate farmed salmon were being blamed for a massive die-off of all manner of species including whales and other mammals in the Pacific waters off that nation’s southern coast.
And if nothing changes, it’s only going to get worse.
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Fish escapes from marine farms raise concerns about wildlife