What does the potential alligator on the other side of the St. Mary's River in Part Eleven symbolize?

The alligator that is poised to eat the children first represents the dangers that they have and will continue to face. However, the fact that they easily outmaneuver the quick animal and end up laughing uproariously at the event proves that the alligator, and all its dangers, is really just a figurative bump that the children can always overcome with ease.