Established in 1907, Jasper National Park (JNP) comprises 10,880 km² of mountainous terrain in western Alberta, Canada. Its large mammals have been protected from hunting and trapping, but are subject to accidental collisions with vehicles and trains on the Yellowhead Highway and the Canadian National Railway (CNR) that transect JNP. This paper reviews the park's historical inventory of Elk (Cervus elaphus), Bighorn Sheep (Ovis Canadensis), and Gray Wolves (Canis lupus), and reports on their number killed by vehicles and trains from 1980 to 2018. Elk population estimates declined from 1000 in 1975 to 318 in 2018. An aerial survey of Bighorn Sheep flown in 2018 over all of JNPs sheep range recorded a decline of 58–62% compared to 1987. In the lower main valley, discrete bands of rams and ewes declined on 2 traditional winter ranges. The road and rail fatalities of Elk and sheep were superimposed on predation. In the late 1970s, wolves were estimated at 160, but reached an undetermined low in 2018 following year-round trapping on JNPs boundaries and accidental fatalities on the park's roads and railways.