Roff trusses are popular breeding places and places of settlement for a lot of animals, on condition, that those rooms aren't fitted up. The timber, as well, must be treated only with well-chosen wood preservatives. By the way there must be suitable entrance holes for the birds. These holes can be structured that way, that only welcom lodgers will move in and others, for instance pigeons, aren't admitted to.

The Barn owls (Tyto alba) almost only occur in the direct settlement areas. They rear their youngs in church steeple timbers, in barns and in the attic. As they have an excellent hearing they are able to locate their prey (first of all mice and shrews) exactly. Depending on the mice supply this owl breeds once or twice a year. The number of eggs and the surviving rate of the offspring directly depend on the food supply, too. Today barn owls are above all in villages and on the outskirts of the towns. There are not only lots of mice, but they are easily to catch there, too.

During the day the Beech marten (Martes foina) hides. It starts searching for food late in the dark or in the night. So it nearly isn't noticed, though it's almost everywhere in our towns. The adaptable animals eat almost everything that offers: pigeons, carrion, left-overs out of the rubbish. As they are very quick and nimble they are able to take run over animals from the road. But sometimes that costs the marten its life.

Looking for a hiding place the beech marten is very flexible and imaginative. They can reach the attics through skylights and gaps in the walls. People notice them only, if they operate as poltergeist.