Guardian News and Media/London

Divers are launching a hunt for historic shipwrecks including one of Sir Walter Raleigh’s ships lost in 1617 off the Isles of Scilly and a paddle steamer sunk off the Northumberland coast in 1838 whose survivors were rescued by Grace Darling and her lighthouse-keeper father.

Of myriad shipwrecks off the British coast dating back to prehistoric times, only a handful of sites known to archaeologists date from before 1840 - just 4% of the 37,000 known and dated sites recorded. English Heritage has now commissioned divers from Wessex Archaeology to conduct a survey of some of the oldest sites, and recommend which are of national importance and should be protected by listing.

Currently just 47 wreck sites have such protection. The sites potentially of interest were identified in a survey last year.

The underwater search will begin in Scilly, where sunken rocks and fierce currents have spelled doom for generations of sailors.

Last month a piece of timber was recovered which may be from Raleigh’s ship Flying Joan, one of two lost when a storm scattered his fleet almost before his treasure-hunting voyage to the West Indies began, soon after he put out from Plymouth.

It was one of his last adventures before he definitively fell out of favour, and was executed the following year in the Tower of London where he had already been imprisoned on several occasions.

In August the archaeologists will be diving at the site where in September 1838 the paddle steamer Forfarshire went down after her steam engines failed, and then lost sails and rigging in a storm, the disaster that made Darling famous.

At first light passengers clinging to the deck, including a woman holding her dead children, were spotted by Darling, who rowed with her father more than half a mile through heavy seas to rescue them. Although 42 people including the captain and his wife drowned, the Darlings rescued nine people and were awarded several medals for bravery including the first ever presented by the RNLI, the lifeboat institute.

Other sites to be investigated include a possible Tudor wreck near Morecambe Bay, and various 19th-century craft including steam tugs and barges lost in ports and estuaries.

Climate change, development and changes in shipping patterns are endangering many wreck sites, exposing remains protected for centuries to being buried in silt on the sea bed.

Mark Dunkley, maritime designation adviser for English Heritage, said: “Watercraft tell a fascinating story of England’s military, industrial and social history, but very little is known about those that existed before 1840. That’s why we are taking the initiative to investigate pre-1840 ships and boats, from wooden sailing vessels to the very start of iron-hulled steam ships.”