RULE: Northern Rough-winged Swallow

<Question>
Match
{Variable}
Direct Choice
{Variable}
Infered Choice

IF
Was the RUMP or LOWER BACK light = {No} OR {Unknown} AND
What colour was the BELLY = {White, or pale (grayish-white)} OR {Unknown} AND
What colour was the BREAST = {Brown, or chestnut (reddish-brown)} OR {Gray, or blue-gray} OR {Unknown} AND
What colour was the THROAT = {White, or pale (grayish-white)} OR {Gray, or blue-gray} OR {Unknown} AND
<What SHAPE was the BILL> = {Straight and thick} OR {Hooked} OR {Downcurved} OR {Unknown} AND
<What LENGTH was the BILL> = {Very short} AND
What colour was the TOP of HEAD = {Brown, or chestnut (reddish-brown)} OR {Gray, or blue-gray} OR {Black, purple, or dark} OR {Unknown} AND
<How BIG was the bird> = {Smaller than a sparrow} OR {Sparrow-sized} AND
<What TYPE of bird was seen> = {Swallow-like} AND
WHEN was the bird seen = {Spring} OR {Summer} OR {Fall}
THEN
Northern Rough-winged Swallow (Confidence: 4)