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B. AB. A. C. A. B. Table 1. Habitat composition of composite availability polygon in 1999 and 2000. Availability (%). Habitat Type. 1999. 2000. 36.6. 36.5. Pasture. 6.2. 6.2. Idle grass. 36.6. 36.1. Cropland. 9.0. 9.0. Woody cover. 10.8. 11.3. Hayland.
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B AB A C A B Table 1. Habitat composition of composite availability polygon in 1999 and 2000. Availability (%) Habitat Type 1999 2000 36.6 36.5 Pasture 6.2 6.2 Idle grass 36.6 36.1 Cropland 9.0 9.0 Woody cover 10.8 11.3 Hayland Farmsteads/ residences 0.9 0.9 Total 100.0 100.0 USING GIS APPLICATIONS TO ESTIMATE WILD TURKEY HOME RANGES AND HABITAT USE IN NORTHEASTERN SOUTH DAKOTA Roger D. Shields*, Lester D. Flake, and Chad J. Kopplin Wildlife and fisheries Sciences, South Dakota State University HOME RANGE ESTIMATION • Relocations estimated by triangulation of 2 – 4 azimuths from GPS’d telemetry stations. Converted to UTM X and Y coordinates with Locate, available in CALHOME (Kie et al. 1996). • Relocations imported into ARCView and used to calculate 90% fixed kernel home ranges using Animal Movement Analysis (Hooge and Eichenlaub 1997) (Fig. 5). • Within sexes, differences tested with ANOVA, mixed models, and non-parametric tests. HABITAT SELECTION • 6 habitats selected for study (Table 1). • Habitats digitized into vector-based GIS using ARCInfo from aerial section photos (Fig. 4). • Habitat use and availability measured at 2 scales (Fig. 5). Figure 6. Habitat selection and avoidance at 2 scales of measurement. Successful nesting females (top) represent the pattern observed by groups in general. Error bars = 1 SE. INTRODUCTION Knowledge of animal movements and habitat use is important to management of wildlife populations. Application of GIS technology to the analysis of movement and habitat use data has increased in recent years. We applied this technology in our study of eastern wild turkeys (Meleagris gallopavo silvestris) released in northeastern South Dakota. Eastern wild turkeys have historically been considered a forest dwelling subspecies, requiring large tracts of forest. Recent introductions have shown the subspecies can thrive in mixed forest-agriculture landscapes. The South Dakota Department of Game, Fish and Parks recently introduced eastern wild turkeys into Grant County, in northeastern South Dakota. Grant County offers only minimal woodland habitat in a highly agricultural landscape. We sought to determine what effect limited amounts of woody cover would have on turkey movements and habitat use. RESULTS • Our estimates 2 – 10 times larger than reported for other northern populations of turkeys. • Most similar to home ranges of populations from forest habitats with poorly interspersed resources. • Home ranges differed by season for both sexes (males: 2=4.73, 2 df, P=0.094; females: F=47.07, 2, 201 df, P<0.001) (Fig.3). • Successful nesting females had larger home ranges than unsuccessful nesting females (t=1.72, 83 df, P=0.089). Figure 5. Scales of habitat analysis. Home range scale: Use = habitats within individual home range Available = habitat within composite availability polygon (created by merging all individual home ranges) Within home range scale: Use = habitats within each buffered relocation Available = habitats within individual home range Figure 3. Differences in size of seasonal home ranges of male and female eastern wild turkeys. Within sexes, seasons marked with same letter did not differ (P0.10). Error bars = 1 SE. METHODS • 6 males and 67 females fitted with radio-transmitters were tracked with truck mounted antenna systems 3 times/week from Jan – Aug, 1999 and 2000 (Figs. 1 and 2). SUMMARY • Seasonal home ranges were much larger than reported for populations of wild turkeys in other northern states, suggesting that resources are poorly distributed in this area. • Home range size differed by season; spring home ranges were larger than winter and summer ranges, likely due to increased movement related to reproductive behavior. • Home range size differed by reproductive class and was associated with reproductive success. • Wild turkeys most often established home ranges with a woody cover-pasture complex and avoided the heavily cultivated landscapes within the study area. • Within home ranges, wild turkey activities were closely tied to woody cover. Cropland, pasture, and hayland habitats were used less than available. Idle grass habitats and farmsteads and residential areas were used proportional to availability within home ranges. • Brooding females established home ranges with greater amounts of cropland, avoiding pasture habitats at both scales of measurement. • During pre-incubation localization, females successful in the nesting attempt avoided pasture at both scales. Season Designations: • Designated 3 seasons (winter, spring, summer) with further classification of females based on reproductive status. • Within the spring season, a special pre-incubation, localizing period of initial nests was studied separately for females. • Thus, 11 “groups” of turkeys studied (Fig. 3). • Brooding females had smaller home ranges than non-brooding females (t=2.95, 53 df, P=0.005). • No difference in home range size during localizing period (t=0.24, 35 df, P=0.815). Figure 4. Study area digitized into ARCInfo and ARCView. Figure 1. Fitting female turkey with radio-transmitter. RESULTS • Woody cover was highly selected by all seasonal groups of turkeys at both scales (Fig. 6). • Cropland was avoided at both scales by all groups, but was utilized in greater amounts by brooding females. • Idle grass and farmstead/residences were generally used in proportion to availability, although idle grass was utilized more by successful localizing females and brooding females. • Pasture was often selected at the home range scale but avoided at the within home range scale; successful localizing and brooding females always avoided pasture habitats. • Hayland was generally used in proportion to availability at the home range scale while it was proportional or avoided at the within home range scale. Figure 2. Truck mounted antenna system. AKNOWLEDGMENTS