""Any beekeeper I have ever known says that bees will leave the hive and beard if the external temperature gets in the 90's. ""
I don't think any beek has ever told you that.
""Any beekeeper I have ever known says that FORAGERS will leave the hive and beard if the external temperature gets in the 90's.
Maybe this, but not the first. They will not abandon brood.
As I said above, Ace, the more you post about trapping, the more you show how little you know. Ventilation is for heat control, not oxygen.