Not a great photo, but I think useful enough for the ID.
Flushed from nest at South Fork Wildlife Area, Kern County, CA. Found while assisting Southern Sierra Research Station researchers, with whom I tagged along specifically to add this bird to my life list. We tried - and failed - to capture any cuckoos in our mist-net (though two came close), but we ended up finding a nest occupied by this bird in a different area of the woodland. We ultimately found 3 or 4 birds total.
Also, I was surprised at how well this photo turned out, albeit heavily cropped. The cuckoo is in the center on an exposed branch, with the bright white belly clearly visible.