In the flying fish scene Pi fights Richard Parker with a boat hook. In one shot, the boat hook has a splintered end but then is completely restored.
When Pi went to drink the holy water in the church, he spilled a drop of water on his shirt that showed up as a wet spot. As the priest comes in and talks with him a moment later, the spot is gone.
When Pi's father is going to feed the goat, the goat is outside the cage, but after Richard Parker has made his move it is on the inside. The goat shouldn't get behind the bars whole.
To demonstrate animal behavior, Pi's father lets a live goat to be fed to Richard Parker. His worker comes in and ties a goat with a rope to the iron bar of the cage. The goat is outside of the cage facing Pi and the family. Then the worker opens the second door so the tiger could come through.
The thing that would happen if the tiger comes in and attacks the goat, which is outside the cage, is the goat will jump backwards to the maximum the rope will allow and the tiger's head will get smashed against the iron bars of the cage injuring him.
The correct way is to tie the goat inside of the cage and then let the tiger in through the second door and watch what happens.
During the entire time Pi is stranded, his beard does not grow even though his hair does. However, not every man is capable of growing a visible beard.
When the ship rolls in the storm, the bedroom where Pi and his brother are sleeping is perfectly still.
When Adult Pi is telling the story, the camera is reflected in his eyes.
One of the Japanese investigators claims that bananas do not float. This can be easily proven wrong with a simple experiment, fresh bananas do indeed float.
Early in the movie, Pi says that Hinduism has 33 million Gods and Goddesses. In Indian English, the word 'crore', which means 10 million, is used rather than million. A fundamental belief in Hinduism is that there are 33 crore Gods and Goddesses. This converts to 330 million, not 33 million. (The use of million rather than crore may be a translation for the benefit of the audience, rather than a goof.)
When standing in French class talking about his name, Pi writes the number pi to nine digits after the decimal point. According to mathematical rounding rules the ninth digit should be 4, not 3 (pi = 3.14159 26535 89793 ... ).