Wren

With the best species name ever: Troglodytes troglodytes :^D

Much beloved, the second wee-est bird in the country. Also used to star on the old farthing coin. (For those under 100 years old, that was worth 1/4 of an old penny, ie there were 960 of them in £1)
The wren is also the King of the Birds, although so small. If ye be good little blippers, one day I may tell you the tale of how he came to attain that exalted status, but yer old grandad's mouth be too dry to speak at the moment.....

Oh! that is an unexpected treat! Just a small one, then.... No, I'll say "When".

Ahh, that's better, cheers!

Well, the birds were gathered all together to decide who was to be their King, you see? The swan said "It should be me, for I am the most beautiful!"
"Nay!" cried the raven, "It should be me, for I am most cunning!"
"Or me," cooed the dove, "for I am most faithful, and gentle!"
"I am wisest!" hooted the owl.
"And I, the most noble!" declaimed the eagle.
"My song is the most melodious ever heard!" the nightingale warbled...
The argument raged on, until the little wren piped up:
"Let us have a competition! He that can soar the highest shall be named King of the Birds!"
It was agreed, and the competition began.
The penguins and ostriches fell out of the running fairly early.
Soon the finches and warblers were left behind, with the thrushes, tits and the game birds.
Eventually only the geese and the raptors were left, still climbing higher.
Up and up they flew, becoming more and more exhausted, until eventually only the mighty eagle was still rising.
As he reached his very limit, and was about to start dropping back; the wren, who all this time had been hidden in the feathers of the eagle's back, popped up and flew yet higher above the eagle.
And that's how he became the King of the Birds...