Decline of regional ecological integrity: Loss, distribution and natural heritage value of roadless areas in Ontario, Canada

Abstract

Only eight years remain to increase nature protection by 20 million ha in Ontario from 10.7% to 30% by 2030 to meet government commitments. Rapid identification and assessment of unprotected roadless areas (RAs) would help to achieve this goal by focussing natural heritage protection efforts in areas with high ecological and conservation value. In Ontario, little is known about the location and extent of RAs, thus the purpose of this study was to map and describe RAs in Ontario, and to discuss their value. Total length of roads in Ontario increased from ∼90,000 km in 1916 to ∼607,500 km in 2020 – an increase of ∼517,500 km (675%) over 104 years. Within Ontario's managed forest region (MFR; excludes the Far North), RAs declined from ∼34 million ha in 1916 to ∼18.5 million ha in 2020 resulting in a loss of ∼15.5 million ha reducing RA cover in the region to 35.6%. Doubling logging production by 2030 per a new Ontario policy could reduce RAs by as much as 20% to ∼14.8 million ha by 2030, potentially resulting in their depletion between 2090 and 2100. In 1880, woodland caribou occupied ∼43 million ha in Ontario's MFR, which declined to ∼10 million ha by 1990. Caribou occupancy in this region could be eliminated by ∼2024 and extirpated from all of Ontario by 2070. If all remaining RAs in the MFR were designated as protected areas, Ontario would achieve 92.7% of the 30 × 30 goal. RAs in Ontario continue to be degraded, fragmented and eliminated.