Inconclusive. It wasn't killed by HPAI. But it also wasn't killed by something physical as far as they could tell - it didn't have injuries consistent with electrocution (in this case, lightning striking near the nest box) and obviously didn't collide with anything. It also didn't appear to have the hematomas I associate with black fly bites and wasn't emaciated.
Still kind of wondering about blackflies since they were so bad, but the long and short is that we don't know. Plant contact reports that the rest of the family is doing well.
Amy