Continuity mistake: Brody has a hold of the large power line, and the shark is gliding along straight for it. In all the shots of Brody holding the power line, the green jacket he wears has wet splashes on it. One patch of water on his right shoulder briefly disappears for one shot, the reappears in the following. (01:46:45)
Continuity mistake: When Tina and Eddie stumble upon the huge dead whale on the beach, they are standing upon a large sand dune to the whale's left. However in the next scene where everyone is gathered around and Dr. Elkins measures the bites in the whale, the sand dune has mysteriously vanished. (00:27:00)
Character mistake: When Dr. Elkins is measuring the Killer Whale, she says "111 centimeters" followed immediately by "68" (centimeters). But her arm spread shown when she says that is not 111 centimeters - about 3.6 feet (1+ YARD wide). It's more like 2 feet. The "68 centimeters" is actually more accurate for the shot though: 26 inches, which is shown.
Other mistake: The dead Killer Whale washed up by the lighthouse was visible from the teens AND in their line of sight while they sat on the shipwrecked boat, also their Catamarans they pulled onto the sand were literally 100 feet away - as seen in the wide shot, but yet it was a surprise when Tina and Eddie come upon it. There's no wrack line showing in the sand so the whale didn't "just wash up "
Visible crew/equipment: On the morning after Brody is fired, when his wife gets up from the kitchen table and talks to their house keeper, the shadow of a crew member holding a boom mic can be seen on the wall on the right side of screen, while the shadow of the boom mic is visible above the doorway. (01:08:20)
Visible crew/equipment: When Brody is at the film developer's darkroom, the developer pulls a covering over what is supposed to be a skylight. Right before the covering is fully pulled over, the "skylight" starts to dim as if it was really a stagelight. (00:50:50)
Continuity mistake: When Mike and all of his friends are at the bar, Mike has a glass of coke on top of a napkin, sitting in front of him. However in one shot of Mike saying “yeah, sure,” the coke has vanished. Through the same bar scene items on the bar change their positions, move around, appear, etc,. (00:53:40)
Continuity mistake: When Brody is in his office, he pours a coffee. Then in one shot you can see the mug on top of the filing cabinet, and the phone rings and Brody walks over and answers it - both hands empty. Yet when he puts the phone down, he picks up the coffee mug from off of the desk, next to the telephone (00:36:45)
Continuity mistake: When the two guys are trying to pull Mike back onto their boat, in the first shot they are pulling the front of his jacket. Then when the shot changes, they are pulling him up by the back of his jacket.