Status, Distribution, and Density of White-tailed Jackrabbits and Black-tailed Jackrabbits in South Dakota

The status of jackrabbit (Lepus spp.) populations throughout the Northern Great Plains has been a cause for concern by wildlife managers in recent years and there has been a paucity of information about the ecology of the white-tailed jackrabbit (Lepus townsendii) and the black-tailed jackrabbit (Lepus californicus) in South Dakota. Since there have been little monitoring efforts for hares, 21 permanent spotlight line transects were established across South Dakota for future surveying efforts. These transects were surveyed to obtain baseline information about jackrabbit density and distribution throughout the state. Jackrabbit density was highest in the northwestern portions of the state and lowest in east central South Dakota. The white-tailed jackrabbit was observed throughout the state, but the black-tailed jackrabbit was only confirmed in south central South Dakota. The reproductive biology of white-tailed jackrabbits was evaluated from 314 animals collected in 44 counties throughout South Dakota from June 2004 to September 2005. Jackrabbits were classified into three age classes based on the closure of the proximal epiphysis of the humerus using x-ray analysis. Fluctuations occurred in measured weights of reproductive organs for both sexes which were used to determine annual reproductive activity. The 2005 breeding season began in late February and proceeded until mid July, approximately 142 days, allowing for females to potentially produce 3.3 litters. Breeding synchrony was apparent throughout the breeding season which was determined from the overlap of four periods of estimated conception and parturition dates. Litter size ranged from one to eight, with an average of 4.6 per female. Prenatal mortality from pre-implantation and post-implantation loss was observed to be greatest (32%) in the first littering period in 2005. Capture methods and home range size of white-tailed jackrabbits has received little attention in the literature and has not been reported in South Dakota. We used live traps and a drive corral to compare capture rates of jackrabbits in three selected fields in Brookings, Kingsbury, and Beadle Counties in eastern South Dakota. The Kingsbury and Beadle sites were primarily grazed pastures while the Brookings telemetry site was largely composed of cultivated land. There were 18 white-tailed jackrabbits captured using live traps with an additional 16 captured using the drive corral. We averaged 0.04 jackrabbits per trap night and 0.29 jackrabbits per man-hour using live traps. Using the drive corral, we averaged 1.23 jackrabbits per trap attempt and 0.48 jackrabbits per manhour. The fixed kernel estimator was used to calculate home range size for 25 jackrabbits which ranged from 0.40km2 to 4.76km2. Average female home range size (1.09km2) did not significantly differ from average male home range size (1.34km2)

REPRODUCTION AND POPULATION CHARACTERISTICS OF WHITE-TAILED JACKRABBITS IN SOUTH DAKOTA

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean litter size was 4.6 per female (range 1-8). Prenatal mortality from preimplantation and postimplantation loss was highest (32%) in the first littering period in 2005

HEALTH AND FERTILITY IMPLICATIONS RELATED TO SEASONAL CHANGES IN KIDNEY FAT INDEX OF WHITE-TAILED JACKRABBITS IN SOUTH DAKOTA

White-tailed jackrabbit (Lepus townsendii) populations in the Northern Plains have been in a general decline for the past decade or longer. A suggested reason for this population decline was reduced body condition of individual jackrabbits due to habitat changes. In order to evaluate body condition, we determined the kidney fat index of 314 white-tailed jackrabbits harvested in 44 counties throughout South Dakota. We removed and weighed kidneys and all perirenal fat associated with the kidneys from collected jackrabbits. We measured kidney weight to determine times of high metabolic activity as indicated by an increase in mass. Body condition was assessed by measuring the amount of kidney fat within each collected jackrabbit. Seasonal fluctuations were evident in average kidney weight and kidney fat for both sexes of white-tailed jackrabbits. The kidney fat index in both male and female peaked in winter and was near 0% in summer. We believe that changes in body condition as indicated by the kidney fat index were related to the onset of breeding season rather than availability of food resources

HEALTH AND FERTILITY IMPLICATIONS RELATED TO SEASONAL CHANGES IN KIDNEY FAT INDEX OF WHITE-TAILED JACKRABBITS IN SOUTH DAKOTA

White-tailed jackrabbit (Lepus townsendii) populations in the Northern Plains have been in a general decline for the past decade or longer. A suggested reason for this population decline was reduced body condition of individual jackrabbits due to habitat changes. In order to evaluate body condition, we determined the kidney fat index of 314 white-tailed jackrabbits harvested in 44 counties throughout South Dakota. We removed and weighed kidneys and all perirenal fat associated with the kidneys from collected jackrabbits. We measured kidney weight to determine times of high metabolic activity as indicated by an increase in mass. Body condition was assessed by measuring the amount of kidney fat within each collected jackrabbit. Seasonal fluctuations were evident in average kidney weight and kidney fat for both sexes of white-tailed jackrabbits. The kidney fat index in both male and female peaked in winter and was near 0% in summer. We believe that changes in body condition as indicated by the kidney fat index were related to the onset of breeding season rather than availability of food resources

Landscape Resource Survey : Dads’ Gates Axis (d)

10 pagesThe Dads’ Gates Axis was to be one of Ellis F. Lawrence’s formal entries to the campus, connecting 11th Avenue to 13th Avenue, and the Memorial Quadrangle beyond. Two of Lawrence’s earliest buildings for the University—Peterson (1916) and Gilbert (1921) Halls—were carefully sited to help terminate the Axis and frame the view south to Memorial Quad. At the time of Lawrence’s death in 1946, though, very little of this scheme was realized. He did succeed in locating the gates with the help of the UO Dads’ Club, the Works Progress Administration and master blacksmith O.B. Dawson. Fred Cuthbert contributed to the design of the Axis, and some features were realized, including the “cloverleaf” entry drive built in conjunction with the Robinson Theater in 1949. By the end of the Mid-Century Era, the southern end of the Axis became partially blocked with the construction of Commonwealth Hall (1952). Since then, little has been done to reinforce the nature of the Axis. The Lillis Business Complex (2003) replaced Commonwealth Hall, and acknowledges the original nature of the Axis through its glazed atrium

Landscape Resource Survey : Memorial Quadrangle (m)

10 pagesThe Memorial Quadrangle was part of Ellis Lawrence’s plan for campus as early as 1914. Intended to be a key element of his grand entrance to campus, Lawrence envisioned a great axial view that initiated at the Dads’ Gates at 11th Avenue and eventually terminated at the head of the Memorial Quadrangle. The quadrangle was to be the university’s more formally-designed campus open space, and Lawrence initially proposed to build a great civic auditorium as its focal point, later to be replaced by the Library. The Quad gets its name from three distinct memorials. The first is a plaque dedicated in 1921 to the athletes who represented the University of Oregon on Kincaid Field. The second consists of the distinctive walks of the Quadrangle that honor the students who fought in the Spanish-American and First World Wars. The third consists of eight Pyramidal English oaks planted in 1940 to honor the senior class president of 1939, Robert Chase Bailey, who drowned in the Mill Race during his senior year. A brass plaque is located on the Library’s terrace fountain as part of this memorial

Distribution and Population Density of Jackrabbits in South Dakota

Distribution of white-tailed jackrabbit (Lepus townsendii) and black-tailed jackrabbit (L. californicus) populations have been thought to be shifting throughout the Northern Great Plains. Anecdotal reports of population declines of white-tailed jackrabbits in recent years have created concern for wildlife managers. We established 21 spotlight line transects (64.4 km) across South Dakota to evaluate jackrabbit distribution as well as to facilitate future survey efforts. We conducted surveys during 2004 and 2005 to obtain baseline information about jackrabbit distribution and population density throughout the state. We observed white-tailed jackrabbits throughout the state, and estimated the highest population density in the northwestern part of the state and lowest in east-central South Dakota. We only observed black-tailed jackrabbits at very low densities in south-central South Dakota in Tripp and Gregory Counties

CALODIUM HEPATICUM IN WHITE-TAILED JACKRABBITS IN SOUTH DAKOTA

White-tailed jackrabbits (Lepus townsendii) are common on the prairie, and an important species in prairie food webs (Lim 1987). Although it has been suggested that jackrabbits have cyclic populations (Donoho 1972, Gross et al. 1974, Anderson and Shumar 1986), there is concern that a general downward trend exists in populations in the Northern Great Plains (Feldhamer et al. 2003). Disease incidence in white-tailed jackrabbits is poorly known (Feldhamer et al. 2003), but may be an important factor in population changes. Tularemia, a disease caused by bacteria (Francisella tularensis), occurs throughout the Northern Hemisphere and can affect many mammals including hares, rabbits and rodents (Feldhamer et al. 2003). As part of a larger study, our objective was to determine the incidence of tularemia in white-tailed jackrabbits in South Dakota. We collected livers from 314 white-tailed jackrabbits throughout 44 counties in South Dakota from June 2004 to August 2005. We examined all livers for any lesions and evidence of infection, and only 16 abnormal livers were found. We submitted these livers to the Animal Disease Research and Diagnostic Laboratory at South Dakota State University for microscopic and bacterial examinations. We detected no evidence of bacterial infection (including F. tularensis) in 298 examined livers or 16 abnormal livers. However, 4 of the livers were infected with Calodium hepaticum, a nematode parasite primarily detected in rodents and in some lagomorphs (Anderson 2000). The remaining livers had lesions characterized by hemorrhage, inflammation, or necrosis with undetermined causes

Landscape Resource Survey : Johnson Lane Axis (n)

10 pagesThe Johnson Lane Axis was part of Ellis F. Lawrence’s plan for the campus as early as 1914. Intended to be a major east-west circulation route for students, the Axis was completed in the early fifties in conjunction with the Erb Memorial Union. The parallel pathway configuration across the Memorial Quad appeared in the early forties as part of a development plan by Fred Cuthbert. At the end of the Mid-Century Era the Axis traversed View east towards the Erb Memorial Union, a principal destination from the Axis.an open landscape dominated by sweeping lawns. Since then, many more trees have been located along the Axis, particularly its eastern portion. The configuration of the Axis has remained virtually unchanged since the end of the Mid-Century Era. Today, with 13th Avenue acting as the predominant east-west pedestrian circulation route on campus, Johnson Lane Axis is a relatively quiet walking area, especially in the section between the Memorial Quad and the EMU

Landscape Resource Survey : Gerlinger Field Green (x)

10 pagesThe most significant features of the Gerlinger Field Green are related to its land use and its connection to Gerlinger Hall. Since its construction between 1919 and 1921, it has been used as a field for athletics and physical education - initially by the women of the campus, but today by all university students. Gerlinger Hall was designed to overlook the playing field and this connection remains unobstructed. The curving row of False cypress appears to have been planted circa 1950