Answer: warbles

AnswerCrossword Clue
WARBLESSings with a trill
WARBLESWhistles a tune
WARBLESEvinces happiness
WARBLESDoes bird calls
WARBLESColoratura's sounds
WARBLESEmulates a canary
WARBLESActs the canary
warbleswarbled song
warblesto sing with trills, as birds
warblesWARBLE, to trill (to play with a tremulous sound)