This diminutive bird has sadly been a declining sight around the countryside. In order to reverse their fortunes, conservationists are now operating nest box schemes to protect the little owls and monitor their progress
At just approximately 125mm tall, the little owl is the smallest of the British owls. It was introduced into Britain during the 19th century by Thomas Powys and by the 1930s had spread to every county south of the River Humber, apart from parts of Wales. Although it did spread northwards in the 1940s, general decreases in numbers were noticed in both the 1950s and 60s. This is likely the result of the loss of hunting habitat, breeding sites and harsh winters.
Little owls can also be found grubbing for worms on the ground which makes the them vulnerable to mammals and other birds of prey. Now the BTO (British Trust for Ornithology www.bto.org) suggests that although the decline is patchy, numbers are in moderate decline, with Breeding Bird Survey data suggesting that the UK population is estimated to have fallen by 24% between 1995 and 2008. The number of breeding pairs is hard to determine, but it could be anything between 4,000 and 8,000 pairs. Their breeding season is relatively short with three to five eggs being hatched during April and May. The eggs are incubated for between 28 to 33 days and mostly starts when the penultimate egg has been laid. The owlets usually leave the nest after 30 to 35 days but may remain much longer. Their parents continue to feed them for up to a month after fledging and they can fly within a week of leaving the nest.
Crepuscular, the little owl is most active at dawn and dusk. They can also be seen hunting during the day when the weather is fine, sunning themselves or simply perching on posts or in trees. Their favourite habitats are orchards and parklands but they can also be found on farmland where there are established trees and hedgerows. Being 'synanthropes' (animals that are adept at surviving amongst us and adapting to situations we put them in) they have also been recorded in the centres of towns and cities, as well as on the edges of moorland, sand dunes and industrial wasteland.
Although the owls diet may vary, a large part is made up from small mammals and invertebrates, such as worms, slugs, beetles, moths and earwigs, with small rabbits and birds occasionally taken.
Owl nest box and ringing monitoring projects
Major Nigel Lewis started his nest box scheme in Wiltshire in 1974, when Dutch elm disease struck the trees that kestrels nested in. He noticed that owls had begun to use the boxes, so the scheme was expanded with boxes designed for them. As he explains, 'Little owls are starting to do well but they have hit a major problem - the baby owls come out of the nests before they can fly, run around on the ground and get eaten by predators, especially where there are no hedgerows to hide in. In our area they have particular problems with buzzards, foxes and badgers, amongst others.' The boxes have been developed so that the owlets cannot get out of the box until they are bigger. The boxes also allow the owls to be monitored by ringing. The ringing begins in May and June and licensed rings from the BTO are used. The owls are carefully removed from the nest box into a ringing bag to keep them calm. They are then measured, weighed and their primary feathers are checked.
Read the rest of this feature on p.77 of the May/June 2013 issue...
By Kate Smith