Functional Changes to the Slate Islands Provincial Park Ecosystem with Successive Arrival of Wolves, Canis lupus, from the Lake Superior Coast


  • Arthur T. Bergerud
  • Brian E. McLaren Lakehead University
  • William Dalton
  • Lo Camps
  • Heather Butler
  • Rodger S. Ferguson



American Beaver, Canis lupus, Caribou, Castor canadensis, Gray Wolf, Lepus americanus, Rangifer tarandus, Red Fox, Slate Islands Provincial Park, Snowshoe Hare, Vulpes vulpes


Observations from 1974-2016 of Caribou (Rangifer tarandus) on the archipelago that comprises Slate Islands Provincial Park allowed us to infer direct and indirect effects of the arrival of Wolf (Canis lupus) pairs in winters of 1993-94 and 2003-04. Wolves created conditions that led to the near demise of Caribou from the islands, including some, but not all, behavioural changes in Caribou consistent with avoiding predators. Caribou on SIPP did not appear to return to calving locations near shoreline areas, nor use them to escape from Wolves by entering water. Shorelines and locations of Patterson Island near a Wolf-occupied Red Fox (Vulpes vulpes) den were the most common Caribou kill locations. Wolves also functionally shifted the ecosystem in Slate Islands Provincial Park via direct and indirect effects on North American Beavers (Castor canadensis), Red Foxes and Snowshoe Hares (Lepus americanus).

Author Biography

Brian E. McLaren, Lakehead University

Associate Professor, Faculty of Natural Resources Management