This kinda thing has been discussed before: https://forum.inaturalist.org/t/screenshot-from-a-bird-voice-identification-app-as-a-photo/42712
I don’t know the answer to the copyright question – while the images of birds in the screenshots are copyrighted, they may be a minor enough inclusion to be “de minimis” or “fair use”. Screenshots of non-free software are also technically non-free, but I think that might be a tough thing to enforce considering how many screenshots of gallery apps and photos of camera UI interfaces there are on the site.
When it comes to the “evidence of organism” question, I’d usually lean toward “no” if there is no audio. The screenshot of the Merlin screen may not even include the spectrogram of the bird in question (it shows a scrolling subset of the spectrogram as you play the audio), and the Merlin ID is not at all guaranteed to be accurate. If you can 100% verify that the bird in question is included in the spectrogram, it technically is evidence, and I would leave it marked as such, but it’s definitely not optimal (especially since the Merlin app doesn’t display a scale, although I’m pretty sure it’s the same 0-11khz scale as the Macaulay Library.) However, what I’ve gleaned from the thread I linked above is that while there is no rule against Merlin screenshots without audio, and that it’s essentially personal preference how you want to handle it, it’s at least strongly discouraged.
If audio is included, though, then you can simply just review the audio to see if the ID is correct. The only real harm I can see that having in that case (other than potentially copyright) is introducing junk data to the CV model.