Washington’s Cascade mountain range houses some of the country’s most intriguing mammals, including black bears, cougars, grey wolves and wolverines. But when Interstate 90 was built in the 1950s, running east-west across the state, it spliced ecosystems between the northern and southern Cascades. The highway also cut across streams, impeding fish passage. “Even though the…

via Why Aren’t More Wildlife Crossings Being Built? — REI Co-op Journal