No abstract

Knowledge of Yellowstone bison (Bison bison) parturition patterns allows managers to refine risk assessments and manage to reduce the potential for transmission of brucellosis between bison and cattle. We used historical (1941) and contemporary (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002) weights and morphometric measurements of Yellowstone bison fetuses to describe fetal growth and to predict timing and synchrony of parturition. Our method was supported by agreement between our predicted parturition pattern and observed birth dates for bison that were taken in to captivity while pregnant. The distribution of parturition dates in Yellowstone bison is generally right-skewed with a majority of births in April and May and few births in the following months. Predicted timing of parturition was consistently earlier for bison of Yellowstone's northern herd than central herd. The predicted median parturition date for northern herd bison in the historical period was 3 to 12 days earlier than for 2 years in the contemporary period, respectively. Median predicted birth dates and birthing synchrony differed within herds and years in the contemporary period. For a single year of paired data, the predicted median birth date for northern herd bison was 14 days earlier than for central herd bison. This difference is coincident with an earlier onset of spring plant growth on the northern range. Our findings permit refinement of the timing of separation between Yellowstone bison and cattle intended to reduce the probability of transmission of brucellosis from bison to cattle. JOURNAL OF WILDLIFE MANAGEMENT 69(4):1716-1730; 2005

No abstract

Areas (km) of population units, total and primary winter ranges, and associated transition ranges of mule deer on the East Front during 1979-1981 2 3. Summer and winter home range sizes (km), number of relocations (N) , and seasonal home range means (km^) for mule deer on the East Front during 1979-1981 4. Total, numbers and proportions of marked animals observed and Lincoln index estimates during March and April for helicopter surveys of mule deer between Birch Creek and Sun River, 1980-1981 5. Number and classification of deer in the early winter helicopter survey on the East Front on January 12-13, 1981 on 5 winter ranges 23 6. Number and percent composition of adult and fawn mule deer on 5 winter ranges on the East Front, January through April, 1981 7. Early and late winter fawn: adult ratios for mule deer and Chi-square test values with associated significance levels (p) on the East Front in 1980 and 1981 .... 8. Fawns :100 adult mule deer for 1979-1980, 1980-1981, long term means, and standard deviations for populations on the East Front in 2 MDFWP management units from 1961-1979 9. Numbers and percentages of sex and age classes for mule deer captured during drive-netting on the East Front in 1981 yiii LIST OF TABLES (CONTINUED) Table Page 10. Numbers and percentages (by sex and age classes) of mule deer checked during 9 days at the Teton Check Station in autumn 1980 28 11. Data on deer hunters and deer harvest from check stations on the East Front study area during autumn 1980 29 12. Origin of hunters (%) checked during 9 days by county and hunting districts in autumn 1980 on the study area :