Can a bird fly in the weightlessness of ISS?

Answer

When a bird flies, there is a balance between the upward thrust caused by the wings and gravity.

There’s no reason the buoyancy force shouldn’t be there anymore in the ISS, because all you need is air for that. However, the effect of gravity suddenly disappears.

I suspect the beast won’t know what hit him and crashes into the ceiling, although you’ll have to do the test to be sure.