At the beginning, Eli is sitting near a campfire. We can clearly see its flames, showing it is still burning. When Eli stands up, the flames has disappeared, even we haven't see him extinguishing the fire.
When Big Eli and his son are in the boat, pulling up shellfish, Little Eli purports to pull a pearl out of the shell. Brother Zack gives Big Eli the opportunity of "letting him fish for mussels."
A. Pearls come from oysters
B. The shellfish hanging from the ropes in the shot (26 minutes into the film) are clams, not mussels OR oysters.