MANY MINDEDWildlife crossings knit together a 3,400-km corridor across the Rockies
The Yellowstone to Yukon Conservation Initiative, launched in 1997, is working to link habitat along a 3,400-kilometer stretch of the Rocky Mountains, from the Greater Yellowstone ecosystem up to Canada's Yukon Territory. The proposed corridor spans five US states, two Canadian provinces, and at least 75 Indigenous territories. To date, the effort reports protecting more than 9.8 million hectares of habitat and supporting construction of about 204 wildlife crossings.
The stakes are concrete. Near Radium, British Columbia, a bighorn sheep herd fell from roughly 350 in the 1990s to perhaps 140 by 2022, with vehicle collisions a major cause; a new wildlife overpass opened there in June 2026. Along a 70-km section of Highway 3, more than 300 collisions with large mammals happen each year, and vehicle strikes plus human-bear conflict kill 5–8% of grizzly bears in the Elk Valley annually.
Connectivity is what keeps protected land from becoming a biological island. A 2025 review in Science warned that isolated reserves become genetic dead ends when disconnected — a risk directly relevant to the global goal of protecting 30% of the planet by 2030. Corridors and crossings turn scattered parks into a functioning system, sustaining the ecological commons that clean water, pollination, and stable ecosystems depend on.
What to watch is whether crossings keep pace with traffic growth. The Elk Valley grizzly population reportedly holds steady only because bears migrate in from elsewhere — a fragile stability. The 140-sheep figure is approximate, and the underlying report was cut off mid-sentence.
Source: Mongabay