I vaguely remember a doco (about a study?) where they established similar fear in crows using similar masks. They tracked these crows, waited for them to breed,

I vaguely remember a doco (about a study?) where they established similar fear in crows using similar masks. They tracked these crows, waited for them to breed, and tested how the babies responded. Saw this over a decade ago now I'd guess, so my memory is fuzzy, but IIRC the takeaway was that the parent crows were able to communicate the knowledge to their offspring that these masks were bad news.