But a council barrister said the barrier is only necessary because the homes would put more than 1,100 new residents close to the Bog.

A planning inquiry into the proposals for homes next to the Bog is now in its third and final week.

Sir David Attenborough has called the nature reserve – which is managed by Yorkshire Wildlife Trust – “irreplaceable” and said it “must be protected”.

Developer Barwood’s ecologist Tom Wigglesworth told the planning inquiry that litter such as beer cans and extinguished campfires had been found on the northern edge of the Bog.

And that plans to build a 175 metre-wide environmental protection zone – with fences – will prevent anti social behaviour and still let wildlife through.

He said: “It will be a barrier to unauthorised access.

“The environmental protection zone will provide a barrier which will reduce any accidental littering such as it being blown across by wind.”

He said the land closest to the development site is a “vulnerable location” and added that the scheme includes an area of public space for dog walking so residents are unlikely to take their pets to the Bog.

He claimed the housing would not cut off wildlife at the Bog because they could fly over the fence or go through or under it and around the edge of the houses.

Stephen Morgan, City of York Council’s barrister said the site is “exceptionally sensitive to disturbance”.

He said: “You don’t dispute the importance of the site.

“Sites like this are a precious resource, it’s an irreplaceable habitat.

“Natural England have concerns about recreational pressure.

“There’s no doubt that those measures are required, because you are bringing a significant population close to the Bog. More than 1,100 people – that’s not an insignificant number.

“There’s no doubt why you thought [these measures would be] necessary.”

The inquiry continues.

Chloe Laversuch , Local Democracy Reporting Service

YORK: Askham Bog developers claim scheme will stop littering and bad behaviour