Figure 11. Grizzly bear (GB) genetic distance (DLR; Paetkau et al. 1997) adjusted for geographic distance (DLR/100 km), between GB sample areas in the northwestern portion of the study area. See Appendix for a comparison of raw (unadjusted) and adjusted genetic distances.
the Continental Divide between Alberta and BC. We found evidence of weak clustering of bears in the Swan Hills from those in Alberta North and the AB Chinchaga areas (Figs. 4 and 10d). Genetic distance–all areas.—We present the genetic distance (both unadjusted and standardized for geographic distance [DLR/100 km2]) results sorted by potential fracture category (natural or human) for convenience (Appendix). Mean adjusted genetic distance differed (t55 ¼ 3.74, P < 0.001) between the 2 types of fractures, natural (DLR ¼ 1.2) and human (DLR ¼ 3.9). The adjusted genetic distance between sampling areas were lowest (<1.0) in the northern undisturbed mountainous areas of our study area (Appendix, Fig. 11). Areas in central BC or associated with icefields and Continental Divides were generally between 1.0 and 2.0 (Appendix). One notable exception was the adjusted distance (3.45) between the Parsnip Mountain and the Parsnip Plateau areas, which was high relative to all other natural areas. Of areas separated by potential human features, bear populations across highways in Alberta have the lowest adjusted genetic distances (Appendix, Fig. 12), low enough to be consistent with other natural areas. The areas within the transborder region with human influence had the highest values of genetic distance, culminating in the genetic distances between the Selkirk South area and other adjacent areas (Appendix, Fig. 13). Several pairs of areas (e.g., Rocky Central Banff East–Rocky Central Banff West, Rocky South Flathead East– Rocky South Flathead West) within the southeast region in the natural category had adjusted genetic distance values <1.0, similar to the far north undisturbed areas (Appendix). We did not provide genetic distances for the Cabinet area as sample sizes were too low for meaningful results, and 6 of 16 samples were from descendents of a translocated female from the Rocky South area (Kasworm et al. 2007b). 20
Analysis 3: Migrant Detection Our effort (genetic and telemetry) to identify individual migrants was carried out in the southeastern region (Fig. 4) within each of the trans-border (Fig. 14) and Alberta sub-regions (Fig. 15). We identified 2,906 individual bears in 24 geographic areas by genetic assignment or physical capture and telemetry (Table 4). We sampled more than 50% of the estimated populations, as derived with DNA-based mark–recapture methods, in most cases in the southeastern study area. Totals of 131 male and 59 female bears moved between adjacent sampling areas (Table 4). Two individual bears were deemed not to be migrants because only 1 of the methods STRUCTURE and GENECLASS detected them (1% of migrants or 0.07% of tested individuals). The number of male migrants across potential fractures ranged from 25 crossing the uninhabited Flathead Valley (Rocky South Flathead East–Rocky South Flathead West) to 0 crossing various highways and human-settled areas (Table 4). Female migrants ranged from 17 across the Flathead Valley to 0 crossing various highways and human-settled areas (Table 4). We found little evidence of female movement across valleys with major highways and settlements in all 3 Mts (Figs. 16–18). Mean movement rates (migrants/sample size) across the entire southeastern region (trans-border and Alberta areas) did not differ between genetic assignment and telemetry (Table 4; assignment ¼ 0.023, telemetry ¼ 0.031, paired sample t-test, t7 ¼ 0.38, P ¼ 0.72). Migrants trans-border region.—Using genetic assignment methods, we found 25 male and 8 female migrants to move between adjacent areas in the trans-border region (Table 4). Of those that crossed major highways, 19 were male and 5 were female. Twenty-four of the migrants moved north–south within Mts; only 9 moved east–west between ranges. We found 1 female migrant that moved into the Selkirk South area (Table 4). There were 1 female and 4 male migrants across Highway 3 in the Wildlife Monographs 180