I would guess that they have not
learned that tactic since it would be happenstance, where as an established camp site would become learned/habitual behavior…
They have!
There are a few places in the BWCA where unattended packs at the end of a portage have been “attacked” by bears. I had a bear that sure was hoping I would put it down one time myself. Black bears are pretty smart, and they learn fast. If a bear finds a tasty snack at the end of a portage, he or she’s going to keep looking for more. Our response has been that if there are any reports of bears in an area, we leave one person with the packs at all times. Slows us down, but not as much as losing our food!
Pam