The trick is to cover their heads with your hands. That stops the chicks from squirming around, relaxing them so much they often fall to sleep.
It makes the task of placing tiny rings on their legs, allowing them to be tracked, a doddle.
And Dave Short, a ringing trainer for the British Trust for Ornithology should know.
As part of the district council-supported Aylesbury Vale Barn Owl Group, he has handled hundreds of protected birds during his career, including last week when he ringed peregrine falcon chicks at the top of County Hall and barn owls in woods north of Aylesbury (the exact location of the owls has to be kept secret given the birds’ value on the black market).
“You have to lay them back in your arms like a baby,” said Dave, who is also licensed to handle great crested newts and bats.
“If you cover their heads they tend to relax – if you put any wild animal in a dark room they will go to sleep.”
Ringing the birds helps track them, providing fascinating information on how long they live, how far they are flying and whereabouts they are settling.
“We spotted a bird with us that had been ringed up in Hull,” said Dave.
“We can also spot if they keep moving from habitat to habitat.
“This might show something is wrong with their habitat. Then we ask has their food of voles gone, has the farmer changed the habitat in some way?”
Ringing can also help identify more sinister issues facing the birds.
Dave said: “For example, with peregrines, criminals try to get them out to Arab states where they are used for hunting and falconry.
“It’s purely done for greed.”
He said peregrines are also targeted by some unscrupulous game keepers who lay traps to protect their own birds.
But he said being able to keep track of the birds can help identify trends if lots of them go missing or are being found dead in certain areas.
He said: “Ringing helps counter the threat, allowing us to track them a lot more easily.
“If guys are doing things they shouldn’t, it allows us to work out where they are coming from.”
PC Dean Kingham, wildlife crime officer based at Waddesdon, agrees.
“Quite a lot of birds of prey we find have been poisoned by game keepers trying to deter them,” he said.
“The dead birds may be dumped in Derbyshire for example but we can use the rings to see if they’ve come from Buckinghamshire.”
PC Kingham added that he often calls on Dave during his investigations.
“He’s great to have around as an expert,” he said.
The ringing project is part of the barn owl scheme, which is run by volunteers and provides nest boxes for farmers and advice on land management.
Barn owl boxes are available for landowners with suitable land for a donation.
The boxes are made by inmates at Springhill Prison.
To date the volunteers have erected more than 150 boxes and are running a programme of monitoring their use and ringing the offspring.
The project has received funding from various sources over the past three years, but the money runs out in July.
It leaves the scheme, now under the guise of Buckinghamshire Owl and Raptor Group, needing to find backing from elsewhere.
Dave, who works full-time as a driver for Serco at RAF Halton, says they are looking towards sponsorship as a way of continuing their good work.
“We are after sponsorship from a timber merchant which can give us ‘X’ amount of timber per year to help build the boxes. There’s lots of ways people can help, for example someone who can service our vehicle. I would be more than willing to go and do talks for them or even take in a live bird for them to see.”