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Coexistence mechanisms such as temporal niche partitioning among sympatric wildlife species may be impacted by continued human disturbance and invasive species. White-tailed deer expansion in North America, a product of landscape and climate change, may alter other species’ diel activity and have implications for conservation of native species. We asked: 1) To what degree does invasive white-tailed deer temporal activity overlap with other ungulate species (mule deer and moose) in landscapes with high human disturbance, versus landscapes with low human disturbance? 2) To what degree does invasive white-tailed deer and predator activity (wolves, grizzly bears, and coyotes) overlap in landscapes with high human disturbance versus landscapes with low human disturbance? Using detection data from infrared remote cameras, we compared a high-disturbance (2019–2020) and a low-disturbance (2009–2010) landscape in the Canadian Rocky Mountains. We used activity pattern analysis to quantify temporal overlap between sympatric mammal species and white-tailed deer. We found that contrary to our hypotheses, sympatric ungulate species maintained activity and temporal overlap with white-tailed deer in both landscapes. Predators did not match the temporal activity of white-tailed deer in the high-disturbance landscape as closely as in the low-disturbance landscape. We conjecture ungulates may be prioritizing periods of optimal foraging or reducing predation risk rather than temporal niche partitioning from invasive-white-tailed deer. Predator species may be more sensitive to anthropogenic disturbance than ungulates and adjust their temporal activity in high-disturbance landscapes. Native ungulates’ lack of diel activity adaptation to white-tailed deer invasions is an important piece of the behavioural puzzle about how western Nearctic systems change with anthropogenic disturbance and human-mediated range shifts.