In 1991 the previous occupant of our house decided to build a tower in his garden for barn owls to breed in. Getting planning permission wasn't guaranteed—one specialist consulted by the planning authority advised that a concrete tower just for owls was over-the-top and the real reason for wanting the tower might be for use as unauthorised accommodation. The method of access to the breeding chamber was also criticised as being quite unsuitable for owls. Fortunately the owls didn't realise this, and proceeded to use the tower for raising their young. However by the turn of the century the owls had stopped using the tower, and that continued to be the case after we bought the house.
In 2006 Channel 4 made a series of programmes about environmental projects, fronted by Bill Bailey, and one of these featured the construction of a barn owl tower. The programme researcher looked for existing examples of such constructions (there weren't many) and the team visited ours. Two hours of filming were condensed to a minute or two in the broadcast programme, consisting mostly of the team agreeing that our owl tower was rather ugly and not a design they wished to copy.
The barn owls had the last laugh though—not long after the programme was broadcast they started to use the tower again and bred successfully for several years. Even after the bitterly cold winters between 2010 and 2012 they raised young, although in 2011 the babies didn't leave the tower until late autumn. This was probably due the the time it took for the adult female to regain her condition before she could lay her eggs after such a harsh winter.
Photographing the owls is difficult—it has to be done from a respectful distance, and the babies tend to stay inside the tower during daylight; even when they are older there is only a short period after sunset when they are outside before it's too dark to take a picture with a normal camera.
In 2010 I bought a cheapish IP camera with infrared lights, tied it to the top of a platform rigged-up in the hedge some way from the tower, and ran a long piece of ethernet cable from a PC in the house down to the camera and left the camera logging video to the PC from about 8pm for about 12 hours. By then the babies were close to leaving the tower for good, but would come out each evening and spend the night doing a bit of flying practice but mostly just perching near the tower entrance making their snake-like hissing noise in the hope their parents would bring them a feed, which happened every few hours. Going through 12 hours of video to find a few interesting events and then extracting them to a web-compatible format is a time-consuming process, but it's interesting to see what goes on in the garden when most of us are asleep.
In 2012 I bought a camera with good low-light sensitivity, high-definition video and a super zoom lens, making it possible to get a few stills and videos of the babies from the comfort of a window in the roof of our house.
At about 8.15 on the evening of 21st June I strapped a safari camera to a branch of a hawthorn tree several metres from the owl tower and left it there until the following morning. It was set to take 2 photos whenever triggered by movement, then wait for at least 2 minutes before taking any more. During the night it took over 1200 pictures, and below is a link to the ones showing the baby barn owls. Until we went through these pictures we had thought there were just 3 babies, but there were more…One Night in June 2014.
Sadly, in recent years the barn owls haven't nested in the tower, but we are confident one day soon they will return.