Michael Caine's plane crashes in the ocean, but when he climbs aboard the Brodys' boat, his clothes are dry. Caine explained that they waited so long for the camera to turn over that his shirt and pants dried in the sun.
One scene begins with a shot of a pair of Caucasian feet under water. The next shot, above the water, shows Clarence, who is not Caucasian, with his feet in the water.
When the shark is chasing Michael Brody, the same footage of Michael swimming fast on the bottom is shown twice. He swims by the same piece of angle iron.
When Michael looked through binoculars at his mom and Hogie as they walked on the beach, Ellen was wearing white sneakers. In the next beach scene, Ellen isn't wearing any shoes.
Near the end of the movie, the shark makes its presence known to Ellen by lifting itself out of the water so its head is over the ledge of the ship. In the next shot, part of the boat is missing. About a minute and a half after the shark eats the shocker, it reappears behind the undamaged boat.
When the shark pursues Michael through the shipwreck, what appears to be an enormous meaty tongue flicks in and out of the shark's mouth as it tries to bite him. Great Whites have an organ called a basihyal, which is very similar to a tongue, but it is stuck to the base of the mouth and cannot move as depicted in the film.
Amity is an island off the Northeastern coast of the US, somewhere around the New York and Massachusetts region. It is approximately 1,250 miles from the Bahamas. It would be impossible for the shark to swim such a distance in less than three days.
It is stated repeatedly in the film, especially by Jake, that it is very rare to find a great white shark in warm water. In fact, great white sharks can be found in almost any temperature zone. What is rare is what has happened in 3 of the 4 "Jaws" movies, to have great white sharks in the cold waters of the American Northeast.
When Mike uses his oxygen tank to escape the shark, he makes an unnaturally rapid ascent of a least 10m to the surface in only a few seconds - yet he suffers no hint of the bends.
Mike brody is being chased underwater by the shark he uses his oxygen tank to come to the surface he comes to the surface quickly he was alright the reality is he would've had the benz which is caused by coming to the water surface too quick.
Hoagie refers to "the shark that killed Martin and Sean", although Martin wasn't killed by a shark, but by a heart attack. However, Ellen had been insisting that his heart attack was from fear of the shark, so he was likely speaking figuratively.
After the boat sinks, the actors are clearly swimming in a tank; the "ocean" bumps up against the edge of the horizon.
When the Shark has been fitted with the tracking device, it it swims away. The lines on the bottom reveal that the shark is in a swimming pool.
In one shot of the shark swimming from behind, stitching in the fabric used to make the shark's skin is visible on it's fin.
Two controlling rods visibly extend from the shark as it hauls Jake down into the water; one comes out by Jake's leg, another is on the shark's stomach.
When Michael and his wife work with the welding torch, the flame's intensity changes several times as the camera shows each of them one by one.
In the closing credits, thanks go to one person listed as being from the "Califorina (sic) Academy of Sciences".
In the introductory scene of Ellen and Sean making dinner, there is a shot where Ellen reaches to the fridge to get something and the shot is inexplicably sped up by the editor.
A number of scenes depict Jake and Michael speaking while Michael is under water and wearing scuba gear. It would be impossible for Michael to speak with an underwater breathing device in his mouth.
Whenever Michael is underwater interacting with the conch, it is very clearly not Lance Guest, as the diver's hands are that of a much older and less tan person. This is likely an actual researcher who knows how to pilot the underwater sub, and correctly handle live conch.
During the attacks on Sean and Ellen in her dream sequence, stock footage of a real great white eating meat suspended from a pole can be seen. Difficult to see because of the quick edits, but noticeable if you slow down the footage.
The shark manages to roar like a lion with its mouth is underwater.
When Michael and Jake are talking on the boat, the hand movements of the guy drumming in the background don't match the rhythm or the dynamics of the sound.
When the shark swims through the sunken boat, the rail on which it "swims" is visible.
When Michael is hiding in the sunken ship and working to shoot to the surface with his air canister, the shark breaks through the wall and tries to attack him. The film then cuts to Michael releasing the pressure from the canister and shooting upward. After this, it cuts back to a wider shot of the shark and Michael as he shoots away. In this second shot, the shark is not moving at all, and the track that it is on is completely visible, as well as multiple cables running into its underside.
After Ellen pushes kills the shark, the boat then begins to rock side to side tripping the "actors"
Some of the shots of Ellen and Hoagie are clearly stunt actors. Ellen is clearly played by a man and Hoagies stunt double is visible with his face and possibly fake wig.
Ellen gets nightmares or flashbacks to the events of the first 'Jaws' film, but how can they be exact? she wasn't present at the events.
Hoagie, Michael and Jake see the shark in the water from inside the plane. They then land the plane in the water and swim to the boat, despite knowing the danger of a shark in the area.