It depends on the bird. Different species make different sounds.
Stereotypically, birds go "tweet tweet". Which scientifically isn't true at all.
bird sound is called called churping
Literally.
Bird song
A bird whistle
The bird meets the fish by the bird EATING the fish that's literally the meeting
"Peep" is a palindrome often used to describe the sound of a baby bird.
tweet tweet
Hachidori (literally: bee bird)
Turkey
There isn't one, but you can literally say "blue bird" by combining blue "aoi" and bird "tori" together.
they sound like a bird
bellbirdbell bird