Magnolia Warblers breed sparingly from about latitude 51 N in se BC also. In
fact, when one is atop the Salmo-Priest in extreme ne Wash, the peaks on the
northern horizon host breeding Magnolia's in the dense forests about their
slopes. They are uncommon breeders at Wells Gray Park also, slightly more
common a bit more northward in Mt. Robson Park (latitude 52+). I'm sure BC
birders could further clarify the breeding range of Magnolia Warblers in BC,
but my observations are that they are regular breeders hundreds of miles south
of "extreme ne BC.
Andy Stepniewski
Wapato WA