Until relatively recently the mute swan, which weighs in at a whopping 11kgs, held the title of Britain's heaviest wild breeding bird. But in 2004 David Waters, a policeman in Wiltshire, hatched first a cunning plan, and then a rather large egg.

We are a real step closer to a self-sustaining population of great bustards in the UK

As a result the swan lost its title and Britain regained its magnificently hefty great bustard, which weighs nearly twice that of a mute swan.

The great bustard (Otis tarda) is actually a native British species, but was persecuted to extinction on our shores by trophy hunters in the 1830’s.

But after a long absence, this heavyweight’s UK population on Salisbury Plain has nearly doubled in two years, and is set to rise again this spring meaning the future of our biggest yet probably least well known bird appears healthy.

It's an exciting time, and we have everything crossed

"We are a real step closer to a self-sustaining population of great bustards in the UK," says David, who founded the Great Bustard Group after learning about the possibility of bringing back Russian bustard chicks to Britain. For many years he and his team did exactly that, but in a bid to improve the birds' chances of survival they changed tack in 2013 and began bringing bustard eggs from Spain into the UK, to be incubated and hatched out on home soil.

The results were remarkable, with survival rates increasing from 10% to an astonishing 40%. With the project's licence to import Spanish bustard eggs renewed for the next few years, it is hoped that an established population of around 100 adults will exist within the next three to five years.

"This has been a record year in terms of the number of nests," explains David, referring to nests built by adults that were hatched out in the UK as chicks. "We have at least five – there may well be a few more we have not found. Many of them are two year old birds and so breeding for the first time.

"It is ambitious to expect a first time young breeder to successfully rear chicks, but we know this can happen. It is an exciting time, and we have everything crossed," he adds.

The bustard’s best and possibly most surprising blessing, however, is that their natural paradise on Salisbury Plain is actually a military training area. This might seem counter-intuitive but the land, owned by the Ministry of Defence (MoD), actually offers the birds the perfect place to live with minimal disturbance from humans.

With this spring heralding a new generation of bustard chicks released onto Salisbury Plain's luxurious chalk plateau, these giant birds look set to become as much a permanent fixture here as Stonehenge itself.

You can find out more about the Great Bustard Project here, and you can also watch a wonderful update about these magnificent birds on Springwatch, which is on BBC Two at 20:00 BST, Monday to Thursday until 16 June.

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