Both Sifeng and Yan believe that if the bird found no way of eating them after staying for a few more days, or even a month, it would leave and go find another prey, but what happened on the third day of their stay in the tiny passage made them realized the big trouble they're in.
Early in the morning on the third day, while they were both busy examining their situation, the bird dived down and moves towards the five flying creatures they killed on their first day here, the bird examine the body of the five beast for several minutes, without doing anything in particular.
The bird examine closely the five beasts for about 30 minutes, the two boys even thought it was going to eat them as they watch with keen interest. They couldn't see it from the tiny passage though, so they move out a bit and could see the bird clearly as it examine each of the beasts' body.
