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Abstract
Population dynamics reflect the unique interactions between individual physiology and behavior with the environment and thus success, which regulates the number, spatial distribution, and genetic composition of populations. Identifying drivers of population dynamics of wild animals is important for determining why and how populations fluctuate spatially and temporally under changing conditions. Therefore, a comprehensive understanding of reproduction and the conditions contributing to successful reproductive events is critical, especially for invasive species because they can significantly alter ecosystems upon establishment in new habitats. Wild pigs are ecological generalists with the highest reproductive potential of any large ungulate, making them one of the most successful invasive species in North America. As populations continue to increase and expand, elucidating factors that influence reproduction will improve population models that can be used to inform management strategies. To address these gaps in knowledge, I conducted a broad assessment of the reproductive ecology of wild pigs across multiple seasons and years to identify individual and environmental attributes that contribute to female reproductive success and juvenile recruitment. I found that reproduction occurred throughout the year, with peaks in conception followed by farrowing that coincided with seasonal food availability. Further, hormone quantification and fetal counts revealed many wild pigs were reproductively mature and contributed to population growth prior to one year of age, although increases in mass and age positively influenced litter size. I found that adjustment of litter size appeared to be the primary reproductive characteristic manipulated to increase fitness rather than adjustment of offspring sex ratio. Females decreased home range size from gestation to farrowing and gradually increased home range post-farrowing during the neonatal care period. Wild pigs selected for both upland and bottomland hardwood forests and avoided pine forests and developed areas during reproduction. I also present the first successful study of known-fate neonate survival, which revealed survival was dependent on neonate sex, pelage coloration, environmental attributes (temperature), and maternal traits (size). Together, these data provide a comprehensive picture of wild pig reproductive ecology in their invasive range that can be used to develop effective management policies that reduce the negative impacts of wild pigs.