Tag Archives: Microtus agrestis

Barn owls bounce back

Every now and again there is a piece of good news regarding the survival of a particular species. Yesterday on the BBC news website was just such a story. It concerned the resurgence of barn owls (Tyto alba, Dansk: slørugle) in the Trossachs around Loch Lomond in Scotland.

Watching barn owls silently quartering fields on a warm summers evening is a rare treat and getting rarer, so it was good to hear that in this area the numbers of field voles (Microtus agrestis) have rocketed by up to ten fold, which has led to a concommitant increase in the breeding success of the local barn owls.

A barn owl quartering a wheat field

Paradoxically, the reason the vole population exploded was the long freezing winters we had last year and the year before, in which large numbers of barn owls perished, but the voles were able to avoid the worst of the cold and move around by tunnelling under the snow and thereby avoid detection by airborn predators.

It was also interesting to read that the owls were maximising the benefit of the vole surplus by storing slaughtered prey in owl boxes, with up to 15 dead rodents in a single box.

Hopefully vole numbers will continue to remain high and barn owl numbers can recover even further. If anyone has heard similar reports about barn owl numbers in other parts of the country please let me know.