Historical clue formulations

• "Black-capped" or "yellow-throated" songbird — 2020-09-07
• New World songbird — 2019-12-06
• Bird with red-eyed and yellow-throated varieties — 2013-01-08
• Olive-colored bird — 2012-12-29
• Bird with a cup-shaped nest — 1997-10-23
• Migratory songbird — 1996-12-29
• Winged insectivore — 1996-02-02
• Olive-green songbird — 1994-11-25
• Red-eyed bird — 1993-12-21