Ah, naval mines. Just the thing to catch unwary vessels.
The use of these Naval Weapons is still legal unlike the anti-personnel land-based version, but you are required to notify people of their use and the rough location of them, so civilian shipping can stay out of the way.
Naval mines in fiction are always portrayed as large metal spheres covered with small spike-like detonators which cause the mine to explode on contact with a ship (or any unfortunate individual). This is based on the appearance of early (World War I-era) naval mines. Most modern ones look rather different. Some are self-contained launch tubes for a homing torpedo that launches when it detects the sound of a ship or submarine's propellers (and is smart enough to distinguish between the two, or even different classes and sizes of ship, and may be set to attack either or both). Others are modified aircraft bombs dropped in shallow waters to lie on the sea bed, with sensor circuitry that detonates when they detect the change in magnetic fields created by the ship's metal hull. The horned type, however, remains a favored weapon for shallow waters and low budgets, and like the Cartoon Bomb is easily recognized by the viewing public.
That page picture has a grain of Truth in Television to it, by the way; fishing trawlers working in the English Channel or the North Sea really do pull unexploded mines, torpedoes and other Second World War-era munitions out of the depths every so often.
At the beginning of For Your Eyes Only, a British spy trawler accidentally fishes in a sea mine and sinks. It seems like a freak accident, but it was actually planted by The Dragon, who later blows up another on dry land to effect his escape from 007.
In Moonraker, Bond's Amazon boat has a number of these in its arsenal, which Bond releases to blow up a pursuing boat.
Those would have had to be Allied ASW mines as the Japanese would not have been able to lay mines and the Allies had no motive to lay any other type. By an example of Hollywood Tactics the submarine seems to have been an Allied sub. While of course mines wouldn't know the difference, Allied subs would not be submerged near Australia. They would be running on the surface, with an escort to prevent friendly fire, too high to be hit by ASW mines.
Hot Fuzz, except it's not underwater when we see it, it's lying around in some dude's garage.
Though the dude hanging onto it claims that it's a dud. It's not.
The Heroes of Telemark have to fend off a mine with a big pole while escaping from Norway.
The 1970's Australian series "Patrol Boat" had an episode where a Japanese WW 2 sea mine had drifted inshore, but blowing it up would mean destroying some historical Aborginal cave paintings. Forget how it was resolved.
Done in the first series of Sea Patrol, when a mine washes up on a beach after a cyclone. While it is unstable, the only real danger comes from a pair of Too Dumb to Live preteen boys who find the mine, don't report it straightaway. One even runs towards it when the bomb disposal unit are about to destroy it to save a tortoise.
Naval mines were used in the 1998 MBX The Battle of Brunei. The Malaysian naval commander gave the Refuge in Audacity order that the minefields be regularly chummed.
It's widely accepted that a Navy Mine sunk the Hospital Ship The HMHS Britannic. The 2000 Made for TV Movie however played with the alternate theory of a submarine torpedo but in the end it was the work of a saboteur.
Common in the old MAD magazine standby, Spy vs. Spy. Sometimes they were hidden in innocent-looking items as a trap, other times they were turned on their owners, but it was as good as guaranteed that seeing one in the setup would result in an explosion by strip's end.
Bloodnok: Mi—? (footsteps running into the distance, splash)
Neddie Seagoon: Funny, he wasn't dressed for swimming.
Eccles: Wait, fellas, there's no need to worry about the mine — it's one of ours!
BattleTech allows for the deployment and use of minefields as part of its advanced (i.e., not strictly tournament-standard) rules. This includes explicitly sea-based conventional, inferno, or command-detonated minefields; inferno mines only work on the surface, the other two can be placed at any given depth.
Sub Culture had whole fields of this, sometimes made extremely dense for some missions.
The player's ship has to navigate minefields every now and then in the Naval Ops series. You can also lay mines, but they don't do very much damage and getting another ship to run into them is iffy at best.
Bug! had these in Quaria. They blew up if you touched them, of course.
Featured in the seventh story mission of Jaws Unleashed. Just touching the chains which they're attached to would make them explode.
The first Venice level in Tomb Raider II has a group of sea mines in by the level exit. Naturally, you couldn't drive your boat through the area unless you wanted to suicide but the trick to clearing the mines is to accelerate to the mines and jump out of the boat before impact.
In Banjo-Tooie, the Submarine Challenge minigame involves destroying a bunch of these (called Shrapnel) for points.
Certain environments had these in Carmageddon. Interestingly enough, they frequently appeared above water as well, still floating while chained to the ground. If run into, the whole sprite would explode and deal dynamic but even damage to the recipient's vehicle based on his/her innate strength and armor level.
In keeping with the game's goofy, nonsensical 1960s setting, Team Fortress 2 features the Sentry Buster robot enemy in Mann Vs. Machine mode. It is half robot Demoman, half sea mine, and all Action Bomb.
Newshounds featured a dolphin whose former job was to find these. He wasn't very good at it. Favourite line: 'Boom boom boom go the ocean zits!'
On Centurions, Max Ray's Depth Charger weapon system was equipped with one called a "hydromine". He once used several of them to stop a tsunami from occurring when a massive meteorite landed in the ocean.
On the Looney Tunes short "Porky's Snooze Reel", a jellyfish swallows a mine whole, despite the narrator's warnings, and is blown into jars of Jell-O.
Maritime mine warfare is actually Older Than They Think: the concept was first introduced in the Ming dynasty China in the 14th century, and used against Japanese pirates (Wako) in the 16th century.
Mines are a menace at shallow and narrow seas. Consequently, littoral countries with vast archipelago or shallow coasts are experts on mine warfare. Examples contain Finland, Greece, Germany, Thailand and Poland. Conversely, they are of little use on depths more than 200 m.
Finland literally bagged the Soviet Baltic Fleet at Kronstadt harbour in 1941 by mining the whole Gulf of Finland. The minefields contained mines on different depth so that not even submarines could get out. After the Armistice 1944, openings were cleared on the minefields so that the Soviet ships could freely enter and exit the Baltic. The minesweeping continued well into the 1950s.
The spiky protrusions on the mine which Donald and the Ducklings have just angled on the cartoon featured are so-called Hertz horns. They are lead horns which contain a small glass ampulla full of electrolyte and two electrodes. When a ship runs into the mine, the soft lead of the horn will bend, breaking the ampulla and letting the electrolyte run in the horn. It will then close an electric circuit, which then in turn will detonate the fuse and the explosive charge on the mine itself.
Sea Mines, like their land-based cousins, could serve as more of a deterrent than a direct weapon. Enemy ships had to sail around known minefields, thus a force could mine waters on the most direct route between an enemy base and their own waterways. Such a tactic was used during World War One to try and limit the effectiveness of German U-Boats by forcing them to take a longer route to get at Allied shipping. This tactic could be combined with shallow-draught wooden-hulled sub-hunting speedboats that could cut across the minefields, attack the German U-Boats, then flee back across the minefields to safety.
Due to an interesting evolution of design, sea mines are also the ancestors of the modern Torpedo, with the original torpedoes being sea mines named for a type of electric ray which would sting you if you came too close. Later tactics developed with boats dragging torpedoes in the path of enemy ships, then later the relatively safer method of sticking the torpedo on the end of a spar and ramming an enemy ship with it (using the towing tactic, the tow lines sometimes got wrapped up in the screw of the boat, dragging the torpedo in). Eventually someone got the bright idea of just attaching an engine to the torpedo and letting the boat stay out of the blast radius.