This may be a question for Cecil as I have no idea how you would calculate the answer, but I shall put it to you as well. How many ships have met watery graves since, say, the year zero? If you want to go back in time further then feel free.
I have no idea what the answer to your question is; I merely feel obliged to observe that there is no Year Zero in the Gregorian system. Nor should there be. Despite the fact that we express them without suffix, year numbers are ordinal numbers (1st, 2nd, 3rd, etc.), not cardinal (0, 1, 2, 3). There’s no 0th in a series (outside of the laws of thermodynamics, a special case, and certain comic book series, a stupid one).
Many more than are at the surface of the ocean, I’m sure. 
As most of them until very recently were wooden, there probably aren’t too many that have left remains; presumably they would have rotted away.
I remember watching a special on Black Sea ship wrecks where the narrator claimed that there had ‘millions’ of ship wrecks over the course of history. I’d say that’s a huge exaggeration (well, with the added ‘s’…a million is conceivable I suppose, if you aren’t asking for how many are still down there, and if your definition of ‘ship’ includes anything that was built by people and can float), but certainly there have been hundreds of thousands at least, all told. Since the year 0 (though there wasn’t actually a year zero, IIRC, zero having been, er, invented at a later date :p)? Just the two world wars probably would be 30-40k if you include all types of merchant and fishing craft as well as war craft (maybe more if you include everything…I arrived at this highly speculative estimate by some quick Google searching of US losses and just guesstimated what everyone else might have lost, since afaict there aren’t any official numbers of every type of craft). A quick look at the estimated list of ship wrecks in the Great Lakes is in the thousands, and that’s mostly large vessels…again, if you are talking about anything man made that floats it’s many times that, as I’m sure Native Americans lost plenty of small craft long before Europeans wandered in.
-XT
Exactly. Wood is destroyed rapidly in the sea as the woodworms eat it all away. It’s very unusual to find anything after a few years.
The metal parts also get encrusted with coral and corrosion, too.
As for a count, there were probably hundreds, if not thousands, of shipwrecks each year during the age of sail, and the number didn’t drop until there was dependable weather forecasting. It was worthwhile to have rescue stations on shore near shipping routes (for instance at Montauk, NY), because they’d be called upon often enough.
Can’t answer the OP, but this map is similar to a nice one we bought while visiting the Outer Banks of NC this past May (first time ever for our family, and thankfully well before hurricane season). Wonderful place.
This is just wrecks around the outer banks, though to be fair, the area is known as “the graveyard of the Atlantic” for good reason. For one small area (relative to the planet), that’s a lot of ships. Extrapolating to include other, similarly dicey areas worldwide and the great wide oceans in general, I’d speculate “a boatload”.
(sorry…)
Side note: those are major/notable wrecks, and do not appear to include local/smaller craft, etc.
Then let’s limit it to metal ships, which is probably a slightly easier task.
I don’t think so. Thousands of years of sailing craft. Ancient China, Ancient India, Roman Empire, Persian Empire, The Phoenecians, the Greeks, The Norse, the Arabs… I’d say at least three thousands years of there being hundreds if not a thousand or more ships lost each year worldwide. Seems like it could well be millions.
Thanks for the lesson on the Gregorian System. I had no idea there wasn’t a year zero. What is it 1 BCE and then 1 CE with nothing in between?
Anyways, my primary interest is how many ships have met with a watery grave (regardless of whether they have rotted away by now). Secondly, how many potential wrecks we could currently find on the ocean floor. As for the definition of a ship, let’s look to Cecil for that: What’s the difference between a boat and a ship? - The Straight Dope
On another, more solvable note. Where are there the most wrecks?
Thanks!
There are probably quite a lot of wooden ship remains dotted around. Half of the Mary Rose survived because it was buried in silt, and the Vasa was raised after more than 300 years underwater with the hull mostly intact.
I’d guess the Mediterranean has the highest number of wrecks. I don’t think it’s the most hazardous sea, but has a long history of heavy shipping activity.
I know of one fairly small area where there are the remains of 16 shipwrecks: Stockton Breakwater, at the entrance to Newcastle Harbour on the east coast of Australia. Here’s a picture of the Adolphe, the largest of those shipwrecks. Note that it’s not on the “ocean floor”: most shipwrecks happen on the coast or in shallow waters, where ships meet rocks, reefs or sand. In the Adolphe’s case, the ship didn’t sink very far, and a lot of the remains of the ship are above sea level.
The Baltic has such a low salinity, that the common ship worm does not live here. Thus Vasa and many other excellent shape old wrecks.
Thanks, I was trying to find specific info on why the Vasa survived in such good condition.
This site lists 116,000 known shipwreck sites.This one has 108,000. This one has 100,000.
I don’t know if there is significant duplication between the lists are if each database is unique. A google search on “shipwreck database” turns up several others.
Wood does not rot under water.
It most assuredly deteriorates over time under water in a natural setting. Whether that is “rotting” in the strict technical sense is another issue.
Color me unconvinced.
From a woodworking site: http://en.allexperts.com/q/Woodworking-2320/Wood-Rot.htm
In salt water, the shipworms make pretty fast work of it, though.
If the wiki page is right and I’m counting right, during the Operation Crossroads atomic tests at Bikini they started out with 95 ships and other than 20 that were hauled off to be studied elsewhere or were clean enough to be scrapped, they’re all at the bottom of the atoll. I suppose those perhaps aren’t “shipwrecks” in that they were all intentionally sunk. Truk Lagoon is also probably a close runner-up.