There's been a brightly colored bird in our trees for a few weeks, and your sighting of it should have told you that spring migration is in full swing. The Bullock's Oriole spends its winters in Mexico, and comes up north in March to breed across the western states. It loves our open woodland areas, so it you live near those great California rolling hills, you've seen them. This is one of those birds that sorts of bursts on the scene, and that's really obvious from the two maps of February and April below the fold:

Here's the eBird map from February, showing just a few sightings around the state:

And here's the map from today:

Hello Bullock's.

(photo by Dave Menke/USFWS)