Revealing mistake: Towards the end, before Quinn is eaten, the shark is "chasing" the boat with 2 barrels. You can see the wire from the boat dragging the barrels off to the right side of the screen.
Continuity mistake: When Quint is up in the crow's nest, Brody tells him "Let Hooper take a turn" (regarding chumming the water). When Quint, while looking down at Brody, says "Hooper drives the boat, Chief", his right arm is across his body and looks to be resting on the safety railing of the crow's nest. When Brody looks up at Quint, his right arm is away from his body and is just holding onto the crow's nest railing with his hand.
Revealing mistake: As Quint smashes the radio, then when Brody yells at him, nearby land is reflected in the windows behind them. There is no land in sight both before and after this scene.
Continuity mistake: When the shark is attacking Hooper in the cage, what happened to the the lines to the barrels they have shot into the shark?
Character mistake: Chief Brody and Hooper go to the wharf to dissect a large tiger shark and examine the contents of its stomach. Finding nothing unusual, Hooper recommends they go offshore that night to search for the real killer shark because "he's a night feeder." Coming from a marine biologist, that remark really makes no sense. Hooper knew that, in addition to eating Chrissie the midnight swimmer, the shark also ate Pippin (the black Labrador retriever) and the Kintner boy in the middle of the day at a public beach. Based on all available evidence, the shark was no more likely to feed at night than in broad daylight.
Suggested correction: The statement is correct, the shark was a night feeder, as opposed to just being a day feeder, meaning the shark will likely be hunting at night.
Again, given all the evidence (including the daytime attacks), Hooper had no more reason to suspect the shark was a night feeder than a day feeder.
Except that's not what the conversation was about, he wasn't speculating on whether the shark was more likely to attack during the day or the night. He simply states they should go out at night to find the real shark responsible for the attacks because that shark will be feeding at night as well (and by going out at night they wouldn't have to face the daytime crowd). If he made an statement such as "the shark isn't a day feeder" or "the shark is strictly a night feeder", those statements could be considered mistakes.
Even when Chrissie was killed at night and two men later on in the movie tried to catch the shark for the reward...at night?
Continuity mistake: When Hooper is lowered in the cage, Jaws approaches with the barrels attached, but when he passes the barrels are gone and never return.
Continuity mistake: When jaws jumps on the back of the boat, Quint falls on the floor and the shark's head is 3/4 submerged - in the next shot the head is fully above the water and submerges again.
Continuity mistake: When Jaws gets trapped between the cage and the boat the shark is really thrashing about. Cut to the surface and Brody is trying to free the cage - the surface of the water does not match the actions of the shark.
Revealing mistake: When Quint is getting eaten, the Orca is now a solid tilted movie set - look at the sides against the sea instead of Quint, and the Orca is not moving.
Continuity mistake: When they are chasing down Jaws with the first barrel on, look at the sea. It's calm at the front of the boat and rough behind when we see close ups of Hooper.
Revealing mistake: When the shark swims away with three barrels, in the next shot all three men are standing at the back of the boat watching it. Look at the sea in front of them and you can see one of the barrels waiting to pop up.
Continuity mistake: Throughout the movie we see a number of underwater scenes with the camera shot looking up under the swimmers where the water is very clear and blue given how many swimmers we can see from a distance. The only problem is that the water everyone is swimming in is greenish and cloudy as can be seen with the camera shots that are half in and out of the water right along side of the swimmers.
Revealing mistake: On the second day aboard the Orca, Quint fires a barrel into the shark and they start to pursue it. There are some overhead shots of Quint on the pulpit and during some of these shots, you can see some sort of tow cable. It's visible on the bottom of the screen between some of the supports of the pulpit.
