The Birds of Ballygáire. Overall i think this is one of the best things you posted here, im biased, i love birds, weird cryptids and the concept of corrupted nature, i love these owl critters, is very simple and effective
My first read i was put off by the ambiguity, decided i like it in the end but still have some issues with it, is cool that you can't be sure if the owls were malevolent or not, related to the epidemic, maybe something darker or just unfortunately off putting animals, maybe there's an allegory im missing...
I think the final line "It would be best to assume the species remains extinct" would have more punch if they were confirmed as a malevolent force or not, i feel like you were going for one of those "The end??" moments were the monster is implied to survive, but is it even a monster? Otherwise, the line could work as a sort of melancholy farewell from the researcher, but as it is i just didn't knew how to feel at the end, i couldn't tell if he was expressing grief or relief over their extinction, the feeling of ambiguity extends to him, he feels too distant as a character, but maybe that's the point?
Anyway, i think this rocks :)