"Some appear and then vanish so people can check records and find out where they were seen and keep looking to see if they reappear.
"People who are regular walkers along the coast or who have dogs should look out for them and let us or local historians know if they spot one.
"The protection we have given to the three wrecks is in recognition of how wonderful and significant they are and we encourage people to go down and see them."
Dating from the late Medieval period to the late 18th century, all three wrecks are rare survivals of wooden sailing vessels found in English waters.
The earliest wreck, known as the Axe Boat, lies in a mud bank on the west side of the Axe River in south Devon and appeared out of the mud in 2001 following changes in the flow of the river.
Dating of extracted samples of wood indicates that it was built between 1400 and 1640. The hull retains characteristic features of medieval ships such as the 'crook'd floor' - a Y-shaped framing timber at the bottom of the vessel.
The Axe Boat is likely to have been used in coastal trade or fishing and such vessels would have once been a familiar site off Britain's coastlines. Axmouth was ranked as a major port by the mid-14th century and accounted for 15 per cent of the country's shipping trade. The other two wrecks lie a few hundred metres apart on the sands at Northam Burrows Country Park in an Area of Outstanding Natural Beauty in North Devon.
They date to the late 18th century and have been exposed by the elements a number of times over the past few decades, most recently following the winter storms of 2014.
The larger wreck at Westward Ho! Is which stands 75 feet long by 22 feet wide (23 metres long x 7 metres wide) is believed to be the remains of the 'Sally', which ran aground on the sands in 1769, while sailing from Oporto in Portugal to Bristol with a cargo of port wine.
The smaller boat was probably a Severn Trow, a small merchant ship working locally in the Bristol Channel coastline around 200 years ago.
It is lying at such an angle that it appears to have been driven ashore in a storm. 11,000 vessels are known to have been wrecked in England waters in the late 18th century and few from this period have been discovered.
Mark Dunkley, Maritime Archaeologist at Historic England said: "Despite the effects of environmental decay and the passage of time, substantial portions of their lower hulls survive, allowing us to determine what type of vessels they were and the role they played in Devon's coastal economy.
"The fact that they're often visible to the public gives them a whole added significance as it's quite rare that such old maritime fabric can be seen by anyone who isn't a diver."
Bill Horner, Archaeologist at Devon County Council added: "While these wrecks have been known about for some time and we have been monitoring their condition, it's great that Devon's maritime past is now being recognised by their protection."
All three wrecks lie in sand or in mud in the inter-tidal zone so are freely accessible to visit on public land at the points when they are uncovered. No diving licence is required, but Historic England advisers visitors to check the tides.
