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Life Sciences Commons

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South Dakota State University

2015

Natural Resources and Conservation

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg Jun 2015

Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg

Natural Resource Management Faculty Publications

Alloparental care (i.e., care for unrelated offspring) has been documented in various avian species (Maxson 1978, Smith et al. 1996, Tella et al. 1997, Lislevand et al. 2001, Literak and Mraz 2011). A male replacement mate that encounters existing broods has options, which include alloparental care or infanticide. Infanticide may be beneficial in some species (Rohwer 1986, Kermott et al. 1990), but in long-lived avian species, like the ferruginous hawk (Buteo regalis) that do not renest within a season, infanticide might be detrimental. Adoption and rearing success likely provide direct evidence of competence of replacement mates as potential parents for …


Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson Jan 2015

Population Ecology Of Rocky Mountain Elk In The Black Hills, South Dakota And Wyoming, Benjamin D. Simpson

Electronic Theses and Dissertations

We conducted a 2-year (2012–2013) study of survival and cause–specific mortality using individually marked adult cow and neonate elk (Cervus elaphus) occupying the southwestern region of the Black Hills. We used known-fate analysis in Program MARK for survival analysis of adult cows and calves. We estimated survival and cause-specific mortality of 49 adult female elk over the 2 years of the study. Annual adult cow survival was 0.85 (95% CI = 0.72–0.87). We documented 12 mortalities with harvest (58.3%) and predation (16.6%) accounting for the majority of known mortalities. We captured and fit 71 neonates < 10 days of age with expandable Very High Frequency (VHF) radiocollars during summer 2012 (n = 37) and 2013 (n = 34). Annual (12 month) survival of elk calves was 0.75 (95% CI = 0.61–0.84) while summer (20 weeks; 15 May–25 September) survival was 0.79 (95% CI = 0.68–0.88). Predation accounted for 87.5% of mortalities; remaining mortalities were from starvation (6.3%) and unknown (6. 3%) causes. We used Global Positioning System (GPS) collars to collect 167,707 locations to determine home range, movement ecology, and macroscale resource selection of 48 adult cow elk. We documented elk using a variety of migration strategies (obligate migrator, resident, conditional migrator, disperser); the majority of the population (58%) was migratory. Spring migration distance travelled ranged from 2.45 km – 74.44 km (n = 42); fall migration distances ranged from 6.41km – 153.95 km (n = 46). We used 99% Brownian Bridge Movement Models to create seasonal and overall home ranges of adult cow elk. Mean overall home range size for conditional migrators was 249.28 km2 (SE = 28.60, n = 7, range = 233.75), for obligate migrant elk it was 227.18 km2 (SE = 13.94, n = 29, range = 346.83), and for resident elk it was 175.65 km2 (SE = 22.75, n = 11, range = 216.04). We used discrete choice models to determine resource selection at the macro-habitat scale of collared adult elk using ArcMap 10.1 data. Adult cow elk selected for open grassland/herbaceous areas and early successional forest areas close to forested edges at higher elevations. Our study showed that elk populations have the ability to thrive within an ecosystem with healthy predator populations.


An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry Jan 2015

An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Bronc Mcmurtry

Electronic Theses and Dissertations

Four different grazing systems: two rotational, a continuous, and a high-intensity, short-duration (mob) system, replicated twice, were evaluated from an economic perspective. Mob grazing is defined as a system having very high stocking rates for a small amount of time. Livestock are forced to eat or trample the vegetation. Stocking rates and average daily gains (ADG) were collected from the UNL Barta Brothers ranch near Rose, Nebraska. The study started in 2011 and lasted until 2014. Using the performance data and other cost data relevant to South Dakota and Nebraska, budgets were set up for each system and extrapolated to …