Assisted migration is a controversial subject for some scientists, and clearly Donnelly and the CBD oppose it. For the case against it, I turn to Anthony Ricciardi and Daniel Simberloff with their opinion piece, "Assisted colonization is not a viable conservation strategy," which was published by Trends in Ecology and Evaluation in 2009:
"Even if preceded by careful risk assessment, such action is likely to produce myriad unintended and unpredictable consequences. Accurate risk assessment is impeded by contingency: the impacts of introduced species vary over time and space under the influence of local environmental variables, interspecific interactions and evolutionary change" Given this lack of predictive power, assisted colonization is tantamount to ecological roulette and should probably be rejected as a sound conservation strategy by the precautionary principle."
One of their biggest concerns (which is shared by most other opponents) is that native species taken out of their home territories will become "invasive" in their new ones and become threats themselves. (We will leave aside here that the label and concept of "invasive" is itself problematic.)
In a following issue of the same publication, researchers Dov F. Sax, Katherine F. Smith, and Andrew R. Thompson responded with a letter entitled, "Managed relocation: a nuanced evaluation is needed."
They outline three reasons they disagree:
First, the precautionary principle is not a stand-alone reason to rule out managed relocation. It states that 'Where there are threats of serious or irreversible damage, lack of full scientific certainty shall not be used as a reason for postponing cost-effective measures to prevent environmental degradation.' In the context of managed relocation, 'precaution' cuts both ways, as a motivation to avoid relocations that might cause unwanted harm and as a motivation to act before a species is driven extinct by climate change"
Second, we know more about the impacts of species invasions than Ricciardi and Simberloff suggest, particularly with respect to species extinction" [E]xtinctions are generally caused by predation as opposed to competition; there are no documented cases to our knowledge where competition from exotic species has been the sole causal factor for the extinction of any native species"
Third, because extinctions are permanent and irreversible, using managed relocation to reduce extinctions at the cost of changing the composition and functioning of ecosystems is a trade-off that some managers might be willing to make. This will be particularly true if most changes that result from relocations are small, and if those that are large are not necessarily detrimental. [my emphasis]
These are just two published pieces out of many on the subject. (I list more at the end.) Despite the iron-fisted insistence of some of those opposed, there is no consensus on the subject of assisted migration in the scientific community at this time. Moreover, given the intensifying effects of Climate Change the topic is sure to be discussed more frequently and in wider circles as time goes on, and more and more is at stake.
Returning to the case of Tiehm's Buckwheat, the managed migration that makes most sense would be into the neighboring areas of the same soil type, which would be over short distances and into small areas. Donnelly mentioned these spots: "It's a little bit of a mystery as to where and why Tiehm's Buckwheat grows because there's lots and lots of channery soil out there that doesn't have Tiehm's Buckwheat on it."
In their petition to the Feds, the CBD addresses this mystery by stating that "there are other unknown factors which determine suitable habitat, since most of the channery soil outcrops do not contain occupied habitat."
One possible explanation of the mystery is that Tiehm's Buckwheat is a very new species, so new that it hasn't moved into these areas yet. I had been wondering about this possibility and when I asked Donnelly if we knew how old the species is, he said no. Genetic research can answer that question, but Donnelly told me that the plant has not been studied to that depth yet.
Recall that as recently as 12,000 years ago, the Great Basin -the region where this plant is found -was a very different place: there were lakes and wetlands and a very different mix of flora and fauna. The current conditions are themselves novel on a longer timeline and are still changing. (The expansion of the range of the Pinyon Pine in the region over just the last 40,000 years is well-documented.) How we found things is not how they always were, and how they would stay if we didn't interfere.
Perhaps, then, it's not the case that the habitat isn't right for Tiehm's Buckwheat but rather that Tiehm's simply hasn't gotten there yet. If so, then a human introduction would be nothing more than an acceleration in the flow.
Would we be "playing God"? Maybe. But that's what we're doing when we bring in a mining operation and wipe a species out. It's also what we're doing if we stand aside and do nothing while it happens.
There are two very real invasions affecting Tiehm's Buckwheat here. The first, obviously, is the introduction of the mining company (regardless of its national origin) with the horrific environmental destruction it will wreak. [Photos.] The second is the imposition of a human dogma that would relegate the plant to extinction in the interest of not interfering.
But it's too late to not interfere. The mining company is already doing that. Collectively, our hands are already dirty. We're already "in." We don't have the luxury of talking about this like we're not part of it. We are. Right now. Shutting down the conversation about an attempted rescue before we can even have it is not only shirking our responsibility -it's pretending that we don't have any. And that, my friends, is some ugly denial.
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