It was all in the timing. My latest read is about the spread of that most egregious invasive – how the Rainbow Trout has pillaged most continents (ably assisted by well meaning anglers) – enroute to world domination …

… and up till now it’s been a source of interest, as my California streams provided the brood stock for half the globe.

Then I stumbled on a couple of recent papers where scientists were attempting to answer this century’s question, “when millions of farmed fish escape, where do they go?” (PDF)

My rationale could’ve been Science, but in all honesty it was pure greed. If I knew which creek 100,000 artificially fattened 8 lb salmon were housed, and knowing that a half empty beer can would be struck and often, I’d abandon family and work responsibilities instantly.

While the small sample cited cannot be conclusive, it suggests if you’re a bit timid about crossing “fat” genes with “big” – you might want to grab the brood stock from another continent.

The researchers tagged and experimentally released 678 farmed fish in Scotland and 597 farmed fish in Norway. Only a small percentage of the fish were recovered by fishermen and reported to the researchers (.6% of the Scottish fish and 7% of the Norwegian fish).

However, the Scottish fish that were caught had travelled very far – up to 1600 kilometers from the release site – and all dispersed to the east towards Scandinavia. Meanwhile, the Norwegian farmed salmon released were  mostly recaptured by fishermen in local waters – 27 in freshwater and 15 in sea – within 150 kilometers of the release site.

One especially interesting hypothesis to explain the easterly bias towards Scandinavia in all fish recaptured including those from Scotland, the authors speculate that this may be due to the dominance of Norwegian broodstock in the existing strains of European aquaculture.

It’s akin to the perfect crime. As your aquaculture endeavor is still new – and while you work out the kinks, the anglers a continent away are catching two-headed Salmon in Lemon Yellow and Orange Orange.

Throw some camouflage tarp over your torn nets and shrug shoulder, “it wasn’t me.”

… no doubt some fellow in Langley, Virginia has read the same treatise and is designing a predator drone that’s shaped like a Salmon, so he can deliver a lethal payload to some poor Afghani who pauses for a cold drink.

Tags: predator drone, escaped salmon, aquaculture, rainbow trout, invasive species, Norwegian broodstock, Atlantic salmon, perfect crime