Common grackles (Quiscalus quiscula) are some of the loudest birds in the park, and often the most irritating. But when the sun shines on them, they are iridescent. And when you photograph them, they really give you attitude. (Very similar, but with a much longer tail, is the boat-tailed grackle.)
This photo is from March 2, 2016, taken at the Pond.
March 2, 2013