Reconstructing Changes in Abundance of White-tailed Deer, Odocoileus virginianus, Moose, Alces alces, and Beaver, Castor canadensis, in Algonquin Park, Ontario, 1860-2004

The history of White-tailed Deer, Odocoileus virginianus, Moose, Alces alces, and Beaver, Castor canadensis, in Algonquin Park since the 1860s is reviewed and placed in the context of changes to the forest, weather, and parasitic disease. Deer seem to have been abundant in the late 1800s and early 1900s whereas Moose were also common but less so than deer. Deer declined through the 1920s as Moose probably increased. Deer had recovered by the 1940s when Moose seem to have been scarce. The deer population declined again in the 1960s, suffered major mortality in the early 1970s, and has never recovered; deer are essentially absent from the present day Algonquin landscape in winter. Moose increased steadily following the decline of deer and have numbered around 3500 since the mid-1980s. Beaver were scarce in the Park in the late 1800s but recovered by 1910 and appear to have been abundant through the early 1900s and at high numbers through mid-century. The Beaver population has, however, declined sharply since the mid-1970s. These changes can best be explained by the history of change to the structure and composition of the Park's forests. After extensive fire and logging in the late 1800s and early 1900s, the forest is now in an essentially mature state. Weather and parasitic disease, however, have also played a role. These three species form the prey base of Algonquin's Wolves, Canis lycaon, and the net decline of prey, especially deer, has important implications for the future of wolves in the Park.