7994 - Laserfiche WebLink

Home Browse Search

Basin would account for less than 0.002% of total historic stream miles. Expansion of the existing range of SB populations and discovery of additional populations has been accomplished through cooperative interagency efforts by Dale Hepworth, Utah Division of Wildlife Resources (UDWR). This assessment indicates overall population status of 23 total SB populations to be .secure, stable. (SST) due to transplants into the historic range (Table 2). Five of the SB populations are remnant (2 on Fishlake NF; 3 on Dixie NF), and eighteen are transplanted (7 on Fishlake NF; 11 on Dixie NF). Two transplanted populations in the Fishlake NF are lake-reservoir populations (Manning Meadow Lake and Barney lake) totaling about 76 surface acres. Existing habitat occupancy in four sub-basins, on two NF's (Fishlake & Dixie NF's) indicate 45% occupancy in thirteen streams within the 47.1 total stream miles renovated. Expansion of SB popula- tions in these waters will continue in these renovated habitats for the remaining 55% of available habitat ensuring .stable, secure. (SST) population status, as well as increasing their use as .brood stock. sources for future renovation-expansion activities (Dale Hepworth UDWR, personal communi- cation, 1996). Hepworth estimates that 25 stream miles in the upper Virgin River sub-basin could have been present historically when a natural geologic stream capture event possibly occurred. Currently, these ten populations on the Dixie NF occupy 16.2 miles of habitat of a total 33 stream miles suitable habitat available. This is 49% stream occupancy but these secure, stable populations that will expand their range into the unoccupied, and available habitat. According to Hepworth, this population of SB will only be used for transplants within the sub-basin of its occurrence. It would not be transplanted into the Sevier River sub-basin, thereby protecting genetic diversity of BCT populations within major sub-basins. Genetic verification of the twenty-three SB populations indicate validation for meristics at 74%, electrophoresis 78%, and in DNA 52% (Table 7). Population status of nine populations on the Fishlake NF indicate 67% .secure, expanding. (SEX), and 33% .secure, stable. (SST) and 7% .at risk, declining. (ARD). Threats from exotic fish presence is minimal, possibly less than 5% since stream rehabilitation and barriers have eliminated past threats to populations from hybridization and competition- displacement (Table 9). Current habitat assessment for SB populations indicate 39% in excellent condition (64% Dixie NF), 31 % good condition (21 % Dixie NF; 67% Fishlake NF), 22% fair condition (33% Fishlake NF; 14% Dixie NF), and 4% each In poor to extremely degraded condition (Dixie NF). Overall habitat trend Indicates increasing habitat availability at 52% (57% Dixie NF; 44% Fishlake NF), stable habitat at 26% (21 % Dixie NF; 33% Fishlake NF), and 22% is .unknown. trend (22% Dixie NF; 21 % Fishlake NF). Habitat condition on lands adjacent to NF's were estimated to be extremely degraded (39% +) with greater than 43% trending toward declining condition (Table 13). Factors affecting habitat condition were sedimentation 26% (Dixie NF at 36%; Fishlake NF at 11 %), and changes in channel morphology, dewatering and lack of woody debris 39% (Dixie NF at 36%; Fishlake NF at 44%) (Table 15). Land use activities contributing to these factors and conditions were grazing 17% (Dixie NF at 14%; Fishlake NF at 22%), logging 11% (Fish lake NF), and roading 14% (Dixie NF). MANAGEMENT IMPLICATIONS The future survival of the BCT within the Bonneville Basin will depend on interagency and inter-state coordination of all responsible state and federal agencies, interested groups, and the public. Each of the four states (UT, NV, ID, WY) BCT species management plans and individual Forest Plans of the nine National Forests must serve as the catalyst for implementing species recovery and habitat 52