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The Service developed Resource Equivalency Analysis tools to calculate the compensatory mitigation needed to offset permitted eagle take via direct mortality, disturbance, or territory loss using power pole retrofits. Electrocution of eagles by power pole elements is a significant cause of mortality to eagles.  The Resource Equivalency Analysis estimates the number of high-risk poles that would need to be retrofitted per eagle taken.

The Resource Equivalency Analysis is based on the current understanding of golden eagle and bald eagle life history inputs, effectiveness of retrofitting high‐risk electric power poles, the expected annual take, and the timing of both the eagle take permit and implementation of compensatory mitigation. As would be expected, the estimated number of eagle fatalities and the permit renewal period affect the number of poles to be retrofitted. Delays in retrofitting would lead to more retrofitted poles owed. New information on changes in the level of take, understanding of the eagle life history, or effectiveness of retrofitting could be used to change the number of retrofitted poles needed for compensation.

As there is evidence that golden eagle populations may be declining, for golden eagles, there is a regulatory requirement for a mitigation ratio of 1.2:1.

While only electric pole retrofitting is presented here in detail, the Resource Equivalency Analysis metric of bird‐years lends itself to consideration of other compensatory mitigation options.

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