England's largest herd of wild red deer is in danger of being decimated and may even face extinction.

That is the fear of many wildlife lovers who have been analysing the true picture of the state of the wild red deer on Exmoor and Somerset's Quantock Hills.

As the glare of publicity that was focused on the shooting of the Exmoor Emperor stag begins to fade, deer enthusiasts have started voicing their fears over the general state of the wild herd.

So much deer shooting has been going on in one area of West hills in recent years that a veteran hunt follower now believes the historic Quantock Staghounds will be forced to cease even exempt hunting within the next two years.

His fears are backed by an official deer count carried out annually by the Quantock Deer Management and Conservation Group. Its figures reveal that a shocking 40 per cent of the herd has disappeared within the past few years.

No one can say if the missing animals are dead or if they have been dispersed further afield due to what many describe as an epidemic of shooting.

It is, though, universally agreed that the wild red deer are in trouble and there has been more shooting in recent years. Opinions vary when it comes to the raft of background reasons why deer suddenly seem to be public enemy number one.

The ban on the age-old sport of hunting with hounds is blamed by many – but it seems modern technology may lie behind the herd's decimation.

An Exmoor marksman said: "The new night-vision scopes and silencers have changed everything. You can buy an amazing night vision rifle sight for less than £3,000 on the internet. Use one of those on a dark night and the deer don't have a chance.

"It might sound like a lot of money but it amounts to just ten good summer stags or 20 hinds," added the man who, like many stalkers, preferred not be named in print. Talk deer shooting on Exmoor and a curtain comes down – especially in the aftermath of the media frenzy surrounding the death of the Emperor stag.

"Some blokes could account for those in a single night. And if you used a modern silencer, no one would hear you. If I shot a deer 20 yards from your house you wouldn't hear it – but without a silencer the whole valley would know."

However, the British Association for Shooting and Conservation, which represents shooting sports, denies that stalkers pose a threat to the overall deer herd. A spokesman said: "Is there a serious threat to deer in the West? The answer is no."