Bird starts to talk excitedly about love (4)
I believe the answer is:
teal
'bird' is the definition.
(teal is a kind of bird)
'starts to talk excitedly about love' is the wordplay.
'starts to' suggests taking the first letters.
The first letters of 'talk excitedly about love' is 'TEAL'.
(Other definitions for teal that I've seen before include "Small river duck" , "Bluish shade of green" , "Strange tale of a duck" , "bird" , "Type of duck" .)