The bell curve tolls for wolves
Posted January 15, 2009
Yesterday we pointed out that NRDC provided a detailed review of scientific arguments for the need for thousands of wolves in the rocky mountain region - that the Fish and Wildlife Service ignored. What they also ignored were comments that they themselves solicited from a wide variety of wolf experts. You may be interested to learn that the Service's recovery goals for wolves are not based on science, but on methodologically flawed opinion polls that were designed to elicit the responses that the Service wanted to hear - and any opinions that didn't conform to their liking were swept under the rug.
I've read them all and I thought that some of these opinions were worth bringing to the Service's attention, again. What I found to be important, relevant arguments to a critical part of the recovery planning process, the Service is calling "selected quotes from one end of the bell curve of all the diversity of opinion that was offered." I'll let you decide. Here are some quotes from the bell curve:
"By limiting the choices to those 3 options approved by the Service, plus a category of 'other', it may unfairly bias the results"
"Aren't these numbers a bit low and the time interval too short?"
"30 breeding pairs is still well below the 1% rule which I believe is overly low itself. I think this population size is still too marginal to be considered viable. These definitions are inadequate."
"There also appears to be agreement that 'several hundreds' of breeders are needed to ensure long-term evolutionary potential. The common value in the literature is Ne = 500 and that translates into the low thousands for a population size in wolves. By this criterion, the individual wolf populations as well as their metapopulation would not be evolutionarily viable."
"a definition of viability without quantify-able [sic] data to back it up is problematic and will be difficult to defend because it is subjective...Some reasonable attempt to model the dynamics of the N. Rockies population showing that 30 (breeding pairs)/300 (wolves) has a reasonable expectation to persist, is needed."
"Survival/mortality rates, age at first breeding, fluctuations in prey numbers, among other factors, should be incorporated into the determination of whether a population is viable...in the absence of such a quantitative assessment, it is subjective and conjectural to simply interpret 30/300 as meeting...population viability."
"Despite the intense study wolves have received in this region, and the wealth of population data that must be available to the Service, the Service has presented no quantitative modeling of the dynamics of the existing populations...Such a modeling effort is essential to gauge the relative worth, from a population viability perspective, of the various definitions you have asked us to consider."
"The fact that the Fish and Wildlife Service has not had the vision to support such a (spatially explicit, individual based) modeling exercise is not sufficient reason to force me to make wild guesses about the parameters of viability."
"None of the definitions offered by the Service is calibrated from the probability, length of time, or specific conditions of survival by 30 breeding pairs of wolves. Unless we are given such information, we are being asked to choose among three 'black boxes.'"
"It may be generally inappropriate to conduct an opinion poll, even from experts, when no quantitative analyses have been conducted to assess the issues at hand."
"Viability is relative, not strictly yes or no...One must consider population growth rates, spatial distribution, and source-sink dynamics, among other factors...The recovery area and population goals need to be expanded."
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