"Yes, people think we're crazy," says Johannes Fritz, with a wry smile.

And surveying the scene, it is easy to see why.

We are in a playing field, in a small village in Austria, close to the Slovenian border.

In it stands a makeshift camp, with all the usual outdoors paraphernalia.

But it is the large aviary, containing 14 northern bald ibis and two human "foster parents" who are gently tending to their avian flock that really draws your attention.

That, and the microlights parked nearby.

For the past couple of days, this unassuming spot has been home to the Waldrapp team, "Waldrapp" being another name for the northern bald ibis.

But the group will not be staying here for long: they are part-way through a month-long effort to take these birds on a 1,300km flight from Germany to Italy.

However, this is no ordinary migration. The scientists are teaching the birds their route by getting them to follow a microlight.

Building trust

The project forms part of a wider conservation plan to save this critically endangered bird, explains Dr Fritz, leader of the Waldrapp team.

Image caption The northern bald ibis has not fared well in the wild

The northern bald ibis was once common throughout Europe, northern Africa and the Middle East.

But today, because of habitat loss and hunting, it has vanished from Europe, leaving diminished populations in Morocco, and just a handful of these distinctive birds in Syria.

Along with other groups around the world, the Waldrapp team is looking into the feasibility of reintroducing birds born in captivity into the wild.

But it is not as simple as opening a cage and setting them free.

Without any knowledge of their migration route, which is usually passed on by their parents, the zoo-born birds cannot survive.

Image caption The foster parents spend all day in the aviary with the birds

So, inspired by a similar project in America called Operation Migration, the scientists teach them their flight plan instead.

But it is a time-consuming process. It begins in spring. As soon as the birds hatch, they are introduced to their new human foster parents.

Then for the next few months, the human stand-ins spend almost every waking hour with the birds, feeding them, grooming them and playing with them.

Sinja Werner, one of the two foster parents in this year's team, says: "We try to be their parents, as best as we can. It's important that they trust you."

Finally, this bond becomes so strong that the birds are willing to follow their parents anywhere. Even if they are sitting in a microlight.

Conservation crisis

While no doubt expensive, people-power heavy and time intensive, the Waldrapp project forms part of a growing movement that is taking conservation further than it has ever gone before.

Gone are the days when saving the flora and fauna was just about safeguarding habitats and putting species protection plans into place.

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Thanks to the fact that we are in midst of the biggest extinction crisis since the dinosaurs were wiped out, some researchers are saying we have to go further.

As well as concentrating on the traditional methods, they claim that we need to invest in and embrace more extreme, more experimental approaches, from hands-on reintroduction programmes like these, to shifting species around the globe and even cloning.

Species are so low in numbers that the only way to deal with their survival is through more intervention Professor John Fa, Durrell Wildlife Conservation Trust

Professor John Fa, director of conservation science at Durrell Wildlife Conservation Trust, says: "We are talking about over 6,000 species under threat, we are talking about pollution increasing, we are talking about habitat fragmentation, we are talking about invasive species. There are many, many threats and these threats are still there.

"In some situations, species are so low in numbers that the only way to deal with their survival is through more intervention, and I think it is pushing us with coming up with more innovative ideas, it is pushing us into coming up with extreme ideas."

And this project certainly fits the bill. The next morning, we get to witness the team in action.

Image caption The idea is to get the birds to follow the foster parent in the microlight - but it does not always work

As dawn breaks, the camp emerges from the darkness into a hive of activity, getting ready for a planned 200km flight that should take the team across the border into Slovenia.

The final preparations are made, and foster parent Sinja takes one last look at her birds before climbing into the microlight.

With a quick burst of speed, it powers across the dewy meadow before gliding up into the air, the fog-drenched countryside becoming ever more distant below.

The aviary opens, and the birds also take to the skies, encouraged by their adoptive mother who repeatedly yells into her loudspeaker: "Here Wileys, come come".

But, it soon becomes clear that the "Wileys", an affectionate nickname for the birds, need a bit more convincing.

Every now and again the foster parent's efforts seem to be working, and the birds gather in a tight V-shaped formation behind the aircraft.

But moments later they scatter, accompanied by increasingly desperate yells from above, pleading with them to come back.

This bizarre mid-air procession continues back and forth for the next 90 minutes, but today, just like naughty children, the birds simply will not do what they are told.

Finally, the team calls it a day, landing a measly 10km from where they set off.

Back on track

A few weeks later, Dr Fritz gets back in touch.

Image caption The team travelled only 10km along their planned route

After this early setback, he said, the birds started to behave, eventually completing their 1,300km migration and arriving in Italy in record time.

He said: "The migration 2010 was fantastic and extraordinary.

"For the first time, the flight speed and the flight distances are fully comparable with that of the wild migrating birds."

With the migration now complete, this flock now have their "flight plan" in place, hopefully allowing them to make their own unassisted migration back to Germany when the time comes for them to breed.

But whatever the future holds for these birds, one thing is certain: these kinds of hands-on conservation efforts are far from easy - or predictable.