You may already know about this, but I was not aware that a pure white Blackbird (the thrush, not the icterid) can be found at Rufford Abbey Country Park in Nottinghamshire, UK. In fact, this leucistic lovely (check out the pic) has resided at the park for the last four years. Thanks to reader Sher Buckner for the tip.
BONUS TRIVIA: Nottingham is , of course, also the home of famous archer, outlaw, and liberal economist (I kid!) Robin Hood.