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Lorencito Canyon Mine -Wildlife Technical ReOOtt <br />• Generally, the transects were conducted between one-half hour before sunrise and 1000 during <br />favorable weather. However, some surveys were conducted during the late afternoon and early <br />evening because all of the surveys could not be completed before 1000 each day. Alternation of <br />the daily transect sampling transect was used to minimize temporal detectabiliry bias. <br />Transect data were analyzed using the comprehensive computer program DISTANCE (Buckland <br />et al., 1993), which utilizes the concept of distance sampling to obtain reliable estimates of density <br />of objects under fairly mild assumptions. Within this program, the use of the Akaike's <br />Information Criterion (AIC) provides an objective, quantitative method for model selection. AIC <br />is computed for each candidate model and the model with the lowest AIC is selected for analysis <br />and inference. In addition, the program enables one to readily compute density, sampling <br />variances and coverages, and standard errors so a measure of precision or sampling variation is <br />available. A minimum of five observations was determined to be necessary for estimating the <br />densities of individual species. <br />Gallinaceous Birds <br />The presence, distribution, and relative abundance of gallinaceous birds within the permit area <br />were determined through aerial surveys, roadside counts, and opportunistic observations made in <br />conjunction with other surveys. The aerial survey and roadside count methods provided <br />• opportunistic observations and distribution information. <br />Other Wildlife Groups <br />Specific surveys were not conducted for wildlife species or groups of species not included in any <br />of the above groups. This category includes predators, furbeazers, and hetpetofauna. Information <br />concerning the presence of these species and their use of the permit area was collected through <br />literature review and opportunistic observations made in conjunction with other field surveys. <br />Threatened or Endangered Species <br />The following threatened and endangered species have been identified within Las Animas County <br />by the U.S. Fish and Wildlife Service: peregrine falcon, bald eagle, Texas horned lizard, Baird's <br />sparrow, mountain plover, southwestern willow flycatcher, Mexican spotted owl, black-footed <br />ferret, and swift fox. Specific surveys for threatened and endangered species were not conducted <br />based on the lack of suitable habitat within the permit area. <br />Level of Field Effort <br />During 1996, a total of 21 person-days was spent conducting field studies for the Lorencito <br />Canyon Mine. This effort was distributed over 8 months and involved seven discrete groups of <br />• studies (Table W-1). May was the most labor-intensive month. <br />Wildlife 475/December 9. 1996 5 <br />