Relative abundance was assessed for small mammals captured on native and restored tallgrass prair... more Relative abundance was assessed for small mammals captured on native and restored tallgrass prairie habitats. Prairie voles (Microtus ochrogaster) (n = 30), meadow voles (Microtus pennsylvanicus) (n = 4), deer mice (Peromyscus spp.) (n = 5), northern short-tailed shrews (Blarina brevicauda) (n = 3), pygmy shrews (Sorex hoyi) (n = 2), and thirteen-lined ground squirrels (Citellus tridecemlineatus) (n = 3) were captured using snap traps. Relative abundance of voles (Microtus spp.) was higher in native prairie (163.3) than in restored prairie (10.2). Rela- tive abundance of deer mice (20.4), thirteen-lined ground squirrels (13.3), and shrews (20.4) was higher in restored than native prairie (< 5.1) habitat. Results indicated that restored prairie habitats provide adequate components (forage, cover) to support viable small mammal communities.
Diets of hartebeest (Alcelaphus buselaphus) and roan antelope (Hippotragus equinus) were assessed... more Diets of hartebeest (Alcelaphus buselaphus) and roan antelope (Hippotragus equinus) were assessed at the Nazinga Game Ranch in southern Burkina Faso, West Africa. Microhistological analysis of feces indicated that dietary overlap was high during the rainy ...
Increased understanding of the influence of habitat (e.g., composition, patch size) and intrinsic... more Increased understanding of the influence of habitat (e.g., composition, patch size) and intrinsic (e.g., age, birth mass) factors on survival of neonatal pronghorn (Antilocapra americana) is a prerequisite to successful management programs, particularly as they relate to population dynamics and the role of population models in adaptive species management. Nevertheless, few studies have presented empirical data quantifying the influence of habitat variables on survival of neonatal pronghorn. During 2002-2005, we captured and radiocollared 116 neonates across two sites in western South Dakota. We documented 31 deaths during our study, of which coyote (Canis latrans) predation (n = 15) was the leading cause of mortality. We used known fate analysis in Program MARK to investigate the influence of intrinsic and habitat variables on neonatal survival. We generated a priori models that we grouped into habitat and intrinsic effects. The highest-ranking model indicated that neonate mortality was best explained by site, percent grassland, and open water habitat; 90-day survival (0.80; 90% CI = 0.71-0.88) declined 23% when grassland and water increased from 80.1 to 92.3% and 0.36 to 0.40%, respectively, across 50% natal home ranges. Further, our results indicated that grassland patch size and shrub density were important predictors of neonate survival; neonate survival declined 17% when shrub density declined from 5.0 to 2.5 patches per 100 ha. Excluding the site covariates, intrinsic factors (i.e., sex, age, birth mass, year, parturition date) were not important predictors of survival of neonatal pronghorns. Further, neonatal survival may depend on available land cover and interspersion of habitats. We have demonstrated that maintaining minimum and maximum thresholds for habitat factors (e.g., percentages of grassland and open water patches, density of shrub patches) throughout natal home ranges will in turn, ensure relatively high (&amp;amp;gt;0.50) neonatal survival rates, especially as they relate to coyote predation. Thus, landscape level variables (particularly percentages of open water, grassland habitats, and shrub density) should be incorporated into the development or implementation of pronghorn management plans across sagebrush steppe communities of the western Dakotas, and potentially elsewhere within the geographic range of pronghorn.
ABSTRACT We used seasonal ground total counts and remote sensing and GIS technology to relate ele... more ABSTRACT We used seasonal ground total counts and remote sensing and GIS technology to relate elephant (Loxodonta africana africana) distribution at Nazinga Game Ranch to environmental and anthropogenic factors. Vari- ables used in analyses were normalized difference vegetation index, elevation, stream density, density of poaching and human illegal activities, distance to dams, distance to rivers, distance to roads, and distance to poaching risk. Contrary to our expectation, road traffic did not disturb elephants. Strong negative relationships were documented between elephant abundance and stream density, distance to dams, and poaching density. Density of poaching and other human illegal activities explained 81%, vegetation greenness 6%, and stream density 3% of the variation in elephant density. Elephant distribution represented a survival strategy affected by poaching, food quality and abundance, and water availability.
ABSTRACT We conducted a 58-day study from 6 September to 2 November 2003 to evaluate size and age... more ABSTRACT We conducted a 58-day study from 6 September to 2 November 2003 to evaluate size and age structure of fox squirrels (Sciurus niger) in mast and non-mast forests in the upper Midwest. Hourly observation and harvest ratios indicated squirrel density was ...
... Due to the dissimilarity of habitat types in eastern and western North Dakota, it is not poss... more ... Due to the dissimilarity of habitat types in eastern and western North Dakota, it is not possible to infer food habits of ... and fecal samples has been documented for white-tailed deer (Odocoileus virginianus), mule deer (0. hemionus) (Anthony and Smith 1977), Sitka black-tailed ...
Swainson&amp;amp;amp;amp;#39;s hawks (Buteo swainsoni) are long-distance migratory raptors th... more Swainson&amp;amp;amp;amp;#39;s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson&amp;amp;amp;amp;#39;s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson&amp;amp;amp;amp;#39;s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%-42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson&amp;amp;amp;amp;#39;s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson&amp;amp;amp;amp;#39;s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson&amp;amp;amp;amp;#39;s hawks arriving to the breeding grounds.
Relative abundance was assessed for small mammals captured on native and restored tallgrass prair... more Relative abundance was assessed for small mammals captured on native and restored tallgrass prairie habitats. Prairie voles (Microtus ochrogaster) (n = 30), meadow voles (Microtus pennsylvanicus) (n = 4), deer mice (Peromyscus spp.) (n = 5), northern short-tailed shrews (Blarina brevicauda) (n = 3), pygmy shrews (Sorex hoyi) (n = 2), and thirteen-lined ground squirrels (Citellus tridecemlineatus) (n = 3) were captured using snap traps. Relative abundance of voles (Microtus spp.) was higher in native prairie (163.3) than in restored prairie (10.2). Rela- tive abundance of deer mice (20.4), thirteen-lined ground squirrels (13.3), and shrews (20.4) was higher in restored than native prairie (< 5.1) habitat. Results indicated that restored prairie habitats provide adequate components (forage, cover) to support viable small mammal communities.
Diets of hartebeest (Alcelaphus buselaphus) and roan antelope (Hippotragus equinus) were assessed... more Diets of hartebeest (Alcelaphus buselaphus) and roan antelope (Hippotragus equinus) were assessed at the Nazinga Game Ranch in southern Burkina Faso, West Africa. Microhistological analysis of feces indicated that dietary overlap was high during the rainy ...
Increased understanding of the influence of habitat (e.g., composition, patch size) and intrinsic... more Increased understanding of the influence of habitat (e.g., composition, patch size) and intrinsic (e.g., age, birth mass) factors on survival of neonatal pronghorn (Antilocapra americana) is a prerequisite to successful management programs, particularly as they relate to population dynamics and the role of population models in adaptive species management. Nevertheless, few studies have presented empirical data quantifying the influence of habitat variables on survival of neonatal pronghorn. During 2002-2005, we captured and radiocollared 116 neonates across two sites in western South Dakota. We documented 31 deaths during our study, of which coyote (Canis latrans) predation (n = 15) was the leading cause of mortality. We used known fate analysis in Program MARK to investigate the influence of intrinsic and habitat variables on neonatal survival. We generated a priori models that we grouped into habitat and intrinsic effects. The highest-ranking model indicated that neonate mortality was best explained by site, percent grassland, and open water habitat; 90-day survival (0.80; 90% CI = 0.71-0.88) declined 23% when grassland and water increased from 80.1 to 92.3% and 0.36 to 0.40%, respectively, across 50% natal home ranges. Further, our results indicated that grassland patch size and shrub density were important predictors of neonate survival; neonate survival declined 17% when shrub density declined from 5.0 to 2.5 patches per 100 ha. Excluding the site covariates, intrinsic factors (i.e., sex, age, birth mass, year, parturition date) were not important predictors of survival of neonatal pronghorns. Further, neonatal survival may depend on available land cover and interspersion of habitats. We have demonstrated that maintaining minimum and maximum thresholds for habitat factors (e.g., percentages of grassland and open water patches, density of shrub patches) throughout natal home ranges will in turn, ensure relatively high (&amp;amp;gt;0.50) neonatal survival rates, especially as they relate to coyote predation. Thus, landscape level variables (particularly percentages of open water, grassland habitats, and shrub density) should be incorporated into the development or implementation of pronghorn management plans across sagebrush steppe communities of the western Dakotas, and potentially elsewhere within the geographic range of pronghorn.
ABSTRACT We used seasonal ground total counts and remote sensing and GIS technology to relate ele... more ABSTRACT We used seasonal ground total counts and remote sensing and GIS technology to relate elephant (Loxodonta africana africana) distribution at Nazinga Game Ranch to environmental and anthropogenic factors. Vari- ables used in analyses were normalized difference vegetation index, elevation, stream density, density of poaching and human illegal activities, distance to dams, distance to rivers, distance to roads, and distance to poaching risk. Contrary to our expectation, road traffic did not disturb elephants. Strong negative relationships were documented between elephant abundance and stream density, distance to dams, and poaching density. Density of poaching and other human illegal activities explained 81%, vegetation greenness 6%, and stream density 3% of the variation in elephant density. Elephant distribution represented a survival strategy affected by poaching, food quality and abundance, and water availability.
ABSTRACT We conducted a 58-day study from 6 September to 2 November 2003 to evaluate size and age... more ABSTRACT We conducted a 58-day study from 6 September to 2 November 2003 to evaluate size and age structure of fox squirrels (Sciurus niger) in mast and non-mast forests in the upper Midwest. Hourly observation and harvest ratios indicated squirrel density was ...
... Due to the dissimilarity of habitat types in eastern and western North Dakota, it is not poss... more ... Due to the dissimilarity of habitat types in eastern and western North Dakota, it is not possible to infer food habits of ... and fecal samples has been documented for white-tailed deer (Odocoileus virginianus), mule deer (0. hemionus) (Anthony and Smith 1977), Sitka black-tailed ...
Swainson&amp;amp;amp;amp;#39;s hawks (Buteo swainsoni) are long-distance migratory raptors th... more Swainson&amp;amp;amp;amp;#39;s hawks (Buteo swainsoni) are long-distance migratory raptors that nest primarily in isolated trees located in areas of high grassland density. In recent years, anthropogenic conversion of grassland habitat has raised concerns about the status of the breeding population in the northern Great Plains. In 2013, we initiated a study to investigate the influence of extrinsic factors influencing Swainson&amp;amp;amp;amp;#39;s hawk nesting ecology in north-central South Dakota and south-central North Dakota. Using ground and aerial surveys, we located and monitored nesting Swainson&amp;amp;amp;amp;#39;s hawk pairs: 73 in 2013 and 120 in 2014. We documented 98 successful breeding attempts that fledged 163 chicks; 1.52 and 1.72 fledglings per successful nest in 2013 and 2014, respectively. We used Program MARK to evaluate the influence of land cover on nest survival. The top model, SDist2Farm+%Hay, indicated that nest survival (fledging at least one chick) decreased as nests were located farther from farm sites and as the percent of hay cover increased within 1200-m of the nest site (34.4%; 95% CI = 27.6%-42.3%). We used logistic regression analysis to evaluate the influence of landscape variables on nest-site selection; Swainson&amp;amp;amp;amp;#39;s hawks selected for nest sites located closer to roads. We suggest that tree belts associated with farm sites, whether occupied or not, provide critical breeding sites for Swainson&amp;amp;amp;amp;#39;s hawks. Additionally, poor breeding success may be related to the late migratory behavior of this species which requires them to occupy marginal habitat due to other raptors occupying the most suitable habitat prior to Swainson&amp;amp;amp;amp;#39;s hawks arriving to the breeding grounds.
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