Huge flagstones flown on to Ilkley Moor to help walkers cross the muddiest stretches are to stay stacked in piles until the summer.

The risk of disturbing ground-nesting moorland birds means the 300 tons of paving stones will have to spend months stacked up alongside the path they were brought in to improve.

A helicopter was drafted in to lift the stones up to the footpath, which runs from the Trig Point to Whetstone Gate, last month.

The operation, part of efforts to improve a kilometre-long stretch of the main east-west route across the moor, was delayed by bad weather in November and December.

The stones are now up on the Bradford Council-owned and managed moor, ready to be laid over some of the muddiest patches on the route, helping to protect the delicate landscape from erosion.

But nature has stepped in once more, and held up the work, ironically until the drier weather.

Work on laying the stones is now not expected to start until July, as it may disturb sensitive ground-nesting birds during the nesting season, from this month until July.

Bradford Council Countryside and Rights of Way Manager, Danny Jackson, said the stones had just been lifted onto the moor in time, before the nesting season interrupted the work.

Mr Jackson said machinery would be used to lay the stones in position, but it was feared this could disturb birds such as grouse, lapwings and curlews, which nest on the moorland.

Walkers on the moor are asked to take special care between March and July. Mr Jackson said: “We’re about to put up signs asking people to keep dogs on leads, it’s a particularly sensitive time of year.”