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<br />'. ,. <br /> <br />derived from biostatistics and acceptable probability of error. In biology/ecology, . <br />an acceptable limit of error is generally agreed upon to be 5% or less (Sokal and <br />Rohlf 1969 and others). The Science Team accepted this as a reasonable <br />approach to the issue at hand. An interpretation would be that in fewer than one <br />case in 20 could an impact of the extent recommended result in any significant <br />impact to a mouse that inhabits the activity area~ Therefore, we concluded that <br />5 % or less of a minimum home range size is a reasonable estimation of the <br />largest area that could be altered in suitable habitat and be exoected to have <br />no effect (or a discountablelinsignificant effect). <br /> <br />Data: The reasoning around the minimum home range is identical to that <br />presented for Issue 1 (see above). Five percent of the minimum home range is an <br />area 50 m2. (530 ft2). This is equivalent to a square that is 23ft on a side. The <br />Science-Team concluded that an impact to an area less than-or equal to 530 <br />ft2 in riparian shrub habitat would have an insignificant chance of taking a <br />mouse or its habitat. <br /> <br />Shape is likely to have an impact on a mouse's ability to survive, as presented in <br />the discussion of Issue 1. For this reason we recommend that the area of impact <br />not exceed 23ft in length in riparian shrub habitat. However, this length is not <br />quantitatively determined and expresses a consensus opinion of the pertinent <br />members of the Science Team. Further, to reduce the potential for cumulative <br />impacts, the Science Team recommends that not more than the recommended area . <br />be disturbed in an area of 109 ft (33.3 m) along a ditch, extending away from the <br />ditch edge 300 ft on both sides of the ditch. <br /> <br />Team Recommendation: The maximum patch size that can be considered as "no effect" <br />or as a discountable effect in occupied habitat of shrubs is recommended to be: <br />1. 530 ft2 (33.3 m2) in shrub habitat (Confidence.Level = High) <br />2. but not more than 23 ft in length (Confidence Level = Med) <br />3. and the approach to the patch will be from one side only to minimize the <br />possibility of fragmentation of habitat (this is suggested by Carron Meaney and <br />agreed to by Rob Schorr and Mark Bakeman) (Confidence Level = Med) <br />4.. The area in which such a disturbance could occur included an area 109 ft along a <br />ditch reach and extended perpendicular from the ditch for 300 ft. (Confidence <br />Level = High) <br /> <br />III. ISSUE 3 <br /> <br />Maximum Allowable Disturbance Area Where Shrub and Non-shrub Habitat, <br />Including Foraging Areas, are Intermingled <br /> <br />The Science Team was asked to consider the case where a proponent needs to conduct <br />some activity in a mouse range that includes riparian shrublands (the primary habitat) and . <br />non-shrubland components (the secondary habitat, e.g., upland foraging areas). This is a <br /> <br />6 <br />