Wildlife Trust officer Kate Titford on how the local branch is working hard to improve conditions for barn owls

Asilent, ghostly-white shape flies past me. It is dusk and I’m standing near a hedgerow on the edge of a field in Chimney Meadows nature reserve in west Oxfordshire.

The bird that’s flown by is a barn owl, that much-loved, iconic farmland bird. But this is a rare sighting.

Barn owls feed on small mammals, particularly short-tailed field voles, as well as mice, bank voles and shrews. These live in rough grass, the sort of tussocky habitat that you find around the edge of fields, next to hedgerows, alongside ditches and streams.

Over the last 60 years in the UK we’ve lost 97 per cent of our traditional grasslands, and 50 per cent of our hedgerows have been lost or damaged. Agriculture has intensified to grow crops in as much of a field as possible and other fields have been turned over to housing developments. Consequently barn owls have less opportunity to find their food.

‘Tidier’ farms mean fewer small mammals for the owls to hunt. Efficient combine harvesters drop less grain for voles and shrews to eat, and rodenticides prevent small mammals from living in farm buildings.

Barn owls have also found themselves homeless. They traditionally nested in holes in trees or inside farm buildings. But old trees have been cut down or lost to disease, and many barns converted into modern homes with no space for a nest.

Barn owls are vulnerable to wet and cold weather. They fly silently, partly because their feathers aren’t waterproof — which means that during cold, wet winters fewer survive to breed in spring. Wet summers mean poor hunting conditions, just when barn owls need plenty of small mammals to raise their young.

As a result of all that, the number of barn owls in the UK fell dramatically during the last century.

The situation sounds grim, but it’s not all bad news. We still have barn owls in Oxfordshire and the Wildlife Trust would like to see more of them.

To give these remaining birds a fighting chance of survival and hope-fully to increase their numbers, the Berks, Bucks & Oxfordshire Wildlife Trust (BBOWT) is putting up nest boxes on reserves where there is good habitat for barn owls to hunt over. You might spot the large, triangular boxes on trees at Chimney Meadows, and a new rectangular box is on a barn at Wells Farm at Little Milton.

BBOWT is also working with landowners outside its nature reserves, putting up nest boxes and advising them about managing the land to provide the right conditions for these owls to thrive.

Barn owls need 50 hectares of grassland to find enough food to raise a family, and if the conditions are right barn owls can breed more than once a year.

Sadly, up to 75 per cent of young barn owls die during their first year, mainly due to lack of food and accidents with vehicles. It is vital we make sure barn owls have the ideal habitats where they can hunt, places to breed, and help to increase their population.

Because barn owls hunt mainly at dusk or in the early morning you may be lucky to see one gliding silently over fields; though you might hear an eerie screech from their nightly roost in a tree.

In the darkness, they use their acute sense of hearing, helped by having one ear higher than the other, to pinpoint their prey in the grass.

Look on the ground below their roost, where you’ll find pellets of regurgitated indigestible parts of their prey. These wide ovals, as long as a man’s thumb, are black and shiny when fresh. Carefully opening up an owl pellet reveals their latest meals: beaks of small birds, a shoulder blade of a vole or fur from a mouse.

Visit www.bbowt.org.uk to discover more about barn owls, including videos of barn owls   raising chicks near the Letcombe Valley nature reserve, and how to dissect an owl pellet