Experts on ancient rock art are to be consulted over the protection of 4,000-year-old stone carvings following vandalism on Ilkley Moor.

Landowner Bradford Council and English Heritage held talks this week about measures to protect ancient rock art, after graffiti was found gouged into one of the stones.

The graffiti at the Hangingstone Rock, close to the Cow and Calf Rocks viewpoint, is thought to have been carved using a chisel.

Protective measures discussed have included carrying out repairs, with the advice of the rock art world, or even covering up the stone with earth.

The damage follows concern in 2011 when black dye was daubed on carved stones and rocks on Rombalds Moor. Experts feared the dye could accelerate the erosion of the rocks.

Although the most recent graffiti incident is believed to have occurred several months ago, the matter was only raised publicly recently, at a meeting of the Friends of Ilkley Moor, and this week at Ilkley Parish Council’s meeting.

There are more than 400 cup-and-ring markings carved on rocks on Rombalds Moor, which includes Ilkley Moor.

The stones were carved during the Neolithic-Bronze Age period about 4,000 years ago.

Bradford Council countryside officer Richard Perham confirmed he met with a representative of English Heritage this week to discuss what action could be taken.

He said: “I met with English Heritage to discuss what options we have, and they’re going to consult with the rock art world. There are several possibilities.”

It has yet to be decided what will be done to protect the carvings, and reduce the risk of further damage to this and other stones.

Options suggested have included filling in the damaged part of the rock, or covering over the stone to prevent further damage. A resin replica of the carved rock could be created and positioned nearby for visitors to see, along with a notice board explaining the area’s archaeological heritage.

Notices informing visitors of the significance of the ancient stone carvings have also been suggested.