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Pronghorn were studied on the Modoc Plateau in northeastern California from 2014 through 2016 to examine movements, reproduction, habitat use and factors affecting survival of adult females and fawns. During the course of the study we radio-collared and 48 adult females and 42 fawns and followed them until their death or the end of the study. After excluding four capture-related mortalities from analyses, overall annual survival for adult females was 69% (± 7%), which is low compared to other pronghorn populations. Mountain lions accounted for 62% of all mortalities and 80% of all predation-related pronghorn deaths. Most (61%) adult mortalities occurred during the summer immediately following the peak birthing period, when adult females are seeking out more secluded areas to hide their fawns. This behavior, coupled with juniper woodland expanding into the sage-steppe habitat on the Plateau, may increase predation risk to pronghorn by increasing the ability of ambush predators, like the mountain lion, to remain undetected during their approach. Fawn mortality was similar across the two years where fawns were radio-collared, with a 57% overall mortality rate. All fawn mortalities occurred within 35 days of collaring (median = 9 days), and unknown causes (37.5%) or suspected coyote predation (21%) accounted for most of the deaths. Fawn survivorship from our collared sample was generally higher than reported in other studies. We used approximately 247,000 point locations collected from GPS collars to examine pronghorn movements and habitat associations on the Modoc Plateau. On a landscape level, adult pronghorn avoid forest year-round, and riparian areas depending on the season. While use of conifer woodlands was always low, it was greater in the spring. On a home range scale, pronghorn used locations that were, on average, less obscured by tall shrubs, in areas that had less shrub cover, more forbs, were 25 m higher in elevation than nearby random locations, and were more likely to be coincident with recent livestock activity. In contrast to observed habitats used during most of the year, females bedded fawns in areas with both short and tall shrubs. Tall shrub coverage at bed sites was similar to random locations, while low shrub coverage at bed sites was substantially greater than at random locations. Selection of fawn bed sites with greater tall shrub coverage may explain the greater association females had with conifer woodland habitats during the fawning season. Daily movement patterns were greatest from noon to 1900 hours, averaging about 400 m/hr. While activity was recorded during all hours of the day, movement was least during the early and late morning hours. Few migration events were noted in the winter of 2014/2015, possibly due to a more mild winter, but most radio-collared females shifted their home ranges during the winter of 2015/2016. Migration movements ranged from very quick range shifts that occurred over a few days, to shifts that spanned several days or even weeks. The combination of vital rates observed in this study predicted a long-term growth rate of λ=0.95, corresponding to a 5% annual decline in the population, and matched the observed population trajectory from 1993-2003. Population growth was by far the most sensitive to changes in adult survival. While a relatively small increase in adult survival is projected to lead to a growing population (i.e., λ>1.00), fawn survival would require an increase of at least 27% above our observed survival to allow for λ>1.00, a rate which exceeds pronghorn fawn survival from any other study reported in the literature.