Under our big pine tree out back I noticed a speckled bird kicking away at the ground with both feet. I later noticed the same type of bird under the neighbor's pine, and one making a mess of our mulch in the front yard. They had a rusty color, with a patch of that color blushing under their eyes, and stripes along their bellies. I haven't seen one like this before so it took some investigating but I think they might be the red Fox Sparrow. The underbrush-kicking, rusty color, and tummy speckles seem to fit what my book described. If that's what they really are, then they are passing through to summer in northern Canada.
(Below, he's just above the snow line in the center of the photo, getting a threat from the robin).