Single word antonym of "flightless" [closed]

I think you can just use flying to describe them; flying birds sounds perfectly normal and isn't a tautology, nor does it only apply to birds in the air, cf. the title of the Wikipedia article 'Flying and gliding animals'.

It's obviously an awkward choice for your example sentence, where another option, volant, could be used instead:

2: flying or capable of flying

(source: Merriam-Webster)

Flighted.

This is the straightforward opposite of flightless.

Edit - reference below:

@WendyG Chambers's English Dictionary, Enlarged Edition with supplement containing 39 pages of additional words and phrases, W&R Chambers Limited, Edinburgh 1914:

"Flight, n. a passing through the air: a soaring: excursion : a sally : a series of steps : a flock of birds flying together : the birds produced in the same season : a volley or shower : act of fleeing : hasty removal.
- adjs. Flight'ed (Milton), flying ; Flight'y, fanciful : changeable : giddy.

- adv. Flight'ily.
-n. Flight'iness. [A.S. flyht - fléogan.] (p 350).