"to provide birds the best fighting chance of surviving threats, at least half of the boreal forest should be protected"

Worth reading, from the Boreal Songbird Initiative:

"To provide birds the best fighting chance of surviving the dual threats of habitat loss and climate change, at least half of the boreal forest should be protected from industrial development."

http://www.borealbirds.org/announcements/boreal-birds-need-half-maintaining-north-americas-bird-nursery-and-why-it-matters