No Through Road

Came across this little guy while scouring the passionfruit vines for final end-of-season fruits, on the vine or on the ground. Found a paltry handful of marginal passionfruits - larger but perhaps not fully ripe on the vine; smaller but riper, on the ground - but this clearly marked the finale of the harvest.
What the ant was after in this neck of the woods is well beyond my capacities for even an educated guess, but whatever it was, it seemed  fairly certain s/he wasn't going to find it at the coiled end of a passionfruit tendril.
There were plenty of other ants exploring this area of the vine at the same time, but what struck me in the 10-minute-ish post-photo observation period was the complete lack of fellow ants who took the same wrong turn down this particular tendril. Not so much as a minor slow-down approaching the tendril intersection, let alone even a tentative first step down it.
How did they know - or how did the original ant get to tell them, in such a short time - that this was a complete dead-end as a potential food pathway? 
Not confident we'll ever know all the complicated intricacies of inter-ant (or inter-bee) reporting mechanisms, but there's no doubt they've got their day-to-day operational comms systems well and truly sorted.