A likely first spring male Yellow-headed Blackbird Xanthocephalus xanthocephalus. Note the brownish black on part of the yellow head.
I am a birder in Pierce County, WA, and as with most places we get vagrant migrants in spring and fall. Frequently the vagrants seem to be sub-adult birds that just get off course more often than adults.
A good example was yesterday when a young male Yellow-headed blackbird showed up on the lawn at a local park. Just a couple of days earlier I had seen an adult on it's breeding grounds, a cattail marsh, in Eastern WA. Note the differences in plumage.
Note the clean yellow head pattern on this adult male.
Here is another view of the young bird from yesterday.
Good birding.
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