While scientists giggle at us trout and salmon anglers, knowing our fragile quarry and how they’re damned to extinction via Global Warming, they throw us a bone by reassuring us that as climate changes over the coming centuries, we’ll not have to deal with “Quasimodo Trout” or something equally misshapen shuffling about the muddy bottom …
… and no, they’re not concerned enough to forswear Ebola research in favor of crafting a more resilient Salmonid, they are merely reassuring us that despite the warming of the Earth’s crust and the dwindling water supply, we’ll not have to fret over Carp-Chinook hybrids or Bluegill Rainbows.
(That indignity being somehow so horrific as to make them blanch and stare at their feet hoping we didn’t notice their earlier glee.)
The latest research stems from the Lake Huron archipelago and centers on a recent study of Canadian Brook trout. Wild and hatchery fish were intermingled and the resultant prodigy examined via the genetic microscope, suggesting that while breeding occurs between wild and hatchery fish, natural selection continues to winkle out foreign genomes in favor of those developed for the unique environment and wild populations win in the end.
It turns out that within five to 11 generations of fish (about 25 to 50 years), the foreign genes introduced into wild populations through hybridization are removed by natural selection. That means fish populations previously bolstered by hatchery stock are, genetically speaking, indistinguishable from purely wild populations.
- from Phys.Org
The journal Evolutionary Applications is host to the research and while considerably harder to follow, suggests the findings are preliminary (as population dynamics are a function of time), yet interloper genes are quickly discarded and the resultant strain become genetically identical to the original wild populations over time.
Although we believe that our study demonstrates that salmonid populations can exhibit no effect of hybridization after 5–11 generations, more studies of this phenomenon are still required to aid policy makers when classifying the protection status or management practices for populations known to be hybridized. Our results additionally provide hope for wild populations of high ecological and economical value currently displaying negative effects as a result of human-mediated hybridization with domesticated conspecifics. If the incoming flow of foreign genes can be stemmed and the environment resembles that experienced by the wild population prior to hybridization, there appears to be a considerable chance that populations will recover, and possibly in less time than previously thought. Similar conclusions have recently been made about canid species exposed to hybridization, but that continue to experience the same selective regimes of their nonhybridized ancestors (Stronen and Paquet 2013).
Global Warming aside – it is a bit of welcome good news in light of how much “cross-pollination” our hatchery practices have induced in North America.
While politicians are quick to grasp any photo opportunity, they’re reluctant to pursue most forms of science beyond that practiced by pollsters. Any increase in watershed temperatures is likely to be met with a “doubling down” on stocking – versus solving the issue completely, and it’s nice to know that should we emerge from this scientific abyss, there might be a few “neo-native” fish to survive with us ..