Last night I warmed Donk in my hands to see if she'd fly in the cage. After a while she shifted so she could look through my fingers so I opened my hand. She stretched one wing straight out and held it tight, vibrating with the effort. Then she stretched the other wing the same way, then both wings. Next she pushed down with both outstretched wings and lifted herself completely off my hand, just balancing on her wing-tips. I wish I had my camera with me.
Then she did something I've never seen before. She twisted her right wing so that the underside was facing up to her chin. She ducked her head under the membrane and rubbed the top of her nose very carefully over the upper side of the wing (Put the back of your hand on the back of your head. Like that.) I could see the bulge her nose made swishing back and forward between her fingers. It took her ages to do one wing, then she swapped wings.
I've read about this but never before saw a bat oiling its wings on the nose glands. Donk was meticulous and very careful to do all her wings.
I am amazed she felt comfortable enough with me to do that on my hand. I've only had her for 3 days.