Robin.
robin
quail
crane
The scientific or taxonomic name would be Mergus serrator.
I'd check that "I" is definitely the fourth letter, because "egret" could be the answer.
There are many bird names beginning with the letters 'bu', some of them include budgie, buff-breasted wren, burrowing owl and bushtit.
Robin
A three letter bird is an owl.
Canary is a bird. Cassowary is a bird.
stork
it is a eagle
Ibis ^^