The UK Government's Wildlife Inspectorate is using the technique normally reserved for police investigating serious human crime to crack down on people who take birds of prey from the wild.

Inspector Justin Evans with blood samples

Using blood samples, the Bristol-based inspectors can trace birds of prey taken illegally.

The DNA also proves the rightful ownership in cases of doubt. A bird registration computer backs up the checks.

The 150 staff at the unit, working in co-operation with police, say the testing is their most effective weapon in fighting the illegal trade.

Jim Chick: "The greatest safeguard that exists."

Earlier this century, the number of birds of prey in the wild plummeted - partly because falconers took too many.

In 198, taking wild birds of prey was outlawed and breeding programmes have flourished ever since.

The testing has helped secure several convictions against wild bird thieves. The maxium penalty is a two-year jail sentence.

Testing the DNA samples

Inspector Justin Evans said: "The DNA testing undertaken by police over the past couple of years has determined that a number of birds that were registered as captive-bred were in fact taken from the wild.

"Some people have been sent to prison for it."

Falconer Jim Chick said: "I think the system is a great arrangement. It's probably the greatest safeguard for bird of prey owners that exists.

"If someone makes false allegations against me and says that bird was stolen, I can say: 'Here's the DNA material, I can prove that it was bred in captivity and you can apologise.'"