Yes, some snakes do that instinctively so they are SURE not to swallow a living rodent that can harm their insides. If you use your tongs to jiggle their prey, it's resets
their "timer" to wait longer & make sure it's dead...The BCI I had for many years often did that. It wasn't that she didn't want to eat, she had a huge appetite, but
living prey was a deal-breaker. Clearly no relation to bull snakes (Pituophis)...they happily gulp down rodents that are still kicking.They are active diurnal hunters with a very different perspective.