THIS is how Aidan Crean celebrates a landmark birthday – by climbing a tree to put up bat boxes. The indefatigable West Belfast environmentalist is one of a small band of nature lovers who are no longer willing to sit back and just watch our wildlife decline. Instead they are getting out there and taking action. Like many of us, Aidan started offering homes to birds with a tit nestbox in the back garden. But the boxes have grown and today the population of barn owls, at least in County Antrim, has been dragged back from oblivion by a series of properly installed and monitored nesting boxes by a small band of tireless bird lovers. The glorious barn owl might be the mascot of the Late, Late Show, but it’s sadly become something of a ghostly legend, a community memory, in the Irish countryside from Kerry to Derry. We carelessly wiped out this bird, mainly by removing the open barns where it once lived and helped keep farmyard vermin in check. And so the nestboxes have been a godsend for this species and now Dúlra gets reports of barn owl sightings from all around Belfast – the latest was this week at Throne Wood in Newtownabbey. Now Aidan and his group have turned their attention to bats. A few months back Dúlra went on one of Aidan’s bat tours around Belfast Castle – and it was clear, even in the darkness, that Aidan was disappointed we didn’t spot a single one, although we did hear them calling on our trackers. “I’m coming back,” he pledged to the crowd at the end of the walk, “to put up a whole pile of bat boxes. The bats of Belfast Castle need help.” Dúlra has a bat box on his chimney – a small wooden one with a tiny slit at the bottom so they can crawl in, but small enough to keep birds out. He’s no idea if it’s being used, but hopefully it has been noticed by the bats that were flying around the street lamp this summer. Attracting a single family is one thing, but Aidan has set his sights on much more. Experts have learned recently that, unlike birds, bats need different types of boxes at different times of the year. They’ll sleep in one place, breed in another and hibernate in another again.