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Polar Bear

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III. Management Goals and Criteria<br />

F. Uncertainty, Assumptions, and the Need for Adaptive Feedback and<br />

Management<br />

The links between the tiers of criteria in this<br />

framework are based on our current understanding<br />

of polar bear demography and threats, which is<br />

incomplete. Thus, in deriving demographic criteria,<br />

assumptions and uncertainty about the demographic<br />

processes (such as regarding Allee effects), the<br />

means and variances of the survival and reproductive<br />

rates, the mechanism and magnitude of densitydependence,<br />

and the role of density-independent<br />

drivers of change give rise to uncertainty about the<br />

demographic criteria. Likewise, the derivation of<br />

threats-based criteria is affected by various types<br />

of uncertainty, such as: uncertainty regarding the<br />

nature, mechanism, and magnitude of the various<br />

threats; uncertainty about the behavioral responses<br />

of polar bears to changing conditions in the marine<br />

ecosystem, such as prey base, denning conditions,<br />

and other effects of climate change; uncertainty in<br />

the trajectory of sea ice as driven by climate change;<br />

and uncertainty in climate forecasts themselves. We<br />

recognize there are other gaps in knowledge that<br />

add to scientific uncertainty. Even if there is strong<br />

policy certainty about the fundamental criteria, the<br />

demographic and threats-based criteria might be<br />

less certain, because of the scientific uncertainty<br />

inherent in their derivation. We also acknowledge<br />

policy uncertainty in the establishment of the<br />

fundamental criteria themselves.<br />

The standards established in this Plan, however,<br />

meet the statutory requirements of the MMPA and<br />

ESA and will result in conservation and recovery,<br />

even in the face of the uncertainties described<br />

above. To achieve the statutory requirements in the<br />

face of uncertainty, we needed to err on the side of<br />

conservation and recovery of polar bears, possibly<br />

at the cost of other fundamental goals. If and when<br />

uncertainties are resolved, it is more likely than<br />

not that the conservation and recovery criteria<br />

can become less demanding, allowing even better<br />

achievement of the other goals.<br />

For these reasons, this Plan should be viewed as<br />

dynamic, not static, and the criteria should be<br />

revised over time as new data are acquired and<br />

critical scientific and policy uncertainties are<br />

reduced or resolved. The fundamental criteria could<br />

be revised if policy insights arise. Depending on<br />

the nature of any changes that may be made in the<br />

fundamental criteria, the demographic criteria may<br />

change. Further, even if the fundamental criteria<br />

do not change, the demographic criteria may be<br />

fine-tuned as new scientific information increases<br />

our understanding of polar bear population dynamics.<br />

The threats-based criteria will likely be subject<br />

to revision as new data help us understand the<br />

nature of the current and emerging threats and<br />

the responses of polar bear populations to them.<br />

Any changes to the demographic and threats-based<br />

criteria will remain founded in the fundamental<br />

criteria.<br />

It is the intent of this Plan to use an adaptive<br />

management approach to revise and update the<br />

fundamental goals, conservation criteria, and<br />

recovery criteria, as well as various assumptions<br />

underlying our analyses, as new scientific and policy<br />

information becomes available that demonstrates<br />

such revisions are appropriate. By using such an<br />

adaptive feedback approach, we will be able to<br />

identify triggers for such revisions to conservation<br />

and recovery criteria and, therefore, maintain<br />

transparency and support for any modifications.<br />

USFWS<br />

<strong>Polar</strong> <strong>Bear</strong> Conservation Management Plan 39

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