Tawny Owl Prey

The two main types of  lower jaw bone seen in the pellets have quite distinct characteristics.

The first type, shown above, holds a row of sharp teeth, looking just like those on large meat-eaters, and obviously belongs to a miniature carnivore. This jaw, which is only 12 mm long, comes from a shrew. These tiny mammals feed on creatures such as insects, worms and woodlice.

The second type of jaw has large, sharp incisors at the front but has a row of teeth further back which are obviously best suited for grinding plant material. Jaws such as these belong to mice and voles, which eat a lot of plant material, such as stems, roots and seeds.

It says a lot about the life of these small mammals when one of the most effective means of establishing their presence in the grounds is the identification of their remains in owl pellets. They are, undoubtedly, very numerous but I seldom see evidence of them, although I do sometimes here the squeaking of voles and I find the occasional dead shrew. (Shrews have an unpleasant taste and some animals will kill them but will not eat them.)