This is one of those flycatchers that you need to catch calling to properly identify. This happens to be a Willow Flycatcher which happens to make a "fitz-bew" sound. There are extremely subtle differences that can be identified when in hand, like the color of the under bill or the amount of yellow on the belly or white around the eye. One of the other indicators is where the bird is found but this is not always the best way, just a starting point. This was taken just next to Capilino Dam in North Vancouver.