We ring maybe 10-15 Little Owl chicks every year, and as a result get next to no recoveries. The last one I can remember is a chick at Scarrington that moved 30 metres from it's nest hole and drowned in a horse-trough (it's not just Barn Owls suffer this fate).
In 2008 we ringed two of a brood of three Little Owls in a walnut tree at Shelton. As this had a narrow nest hole entrance, it meant going back with Louise Gentle to use her slender arms to extract the chicks. Just recently, Mick Pearson was checking another natural nest site at Woodborough (one I'd removed debris from to encourage the Little Owls to use again) and controlled one of the Shelton chicks on its own three small chicks. That's a movement of 15 km, which is pretty good in Little Owl terms.
PS Success at last! One of the Little Owl nest boxes (of the Bob Sheppard design) that Duncan & I put up in Lincs in Feb/March had an adult & single chick in it last week. That's the first time I've managed to get Little Owls into a purpose designed nest box!