Monitoring and conserving Scotland's birds of prey
Long-eared owls are usually found on the wooded edges of moorland and rough grassland and other areas with high populations of small mammals, such as young tree plantations. They feed principally on field voles and other small mammals, but will also take small birds (Wooller & Triggs 1968, Glue & Hammond 1974). They do not build their own nests, but use the old nests of other birds such as crows and sparrowhawk, or use platforms and boxes provided by conservationists. As the forestry plantations established in Scotland during the 20th century are restructured, suitable habitat is increasing. Whilst predominantly found nesting in coniferous woods, they also use broadleaf woodlands on some islands, and have even been found exploiting holes in crags and bracken in Sutherland, and heather in open hill country in Shetland.
The long-eared owl is a secretive breeding species being not readily found during normal ornithological surveys and so is regularly under-recorded. When well-grown young give their "squeaky gate" call they can be heard at considerable distance on still summer evenings. Thus, at the right time of the year, when specifically searched for, long-eared owls can be detected. As a result of their secretive nature, it is difficult to be sure whether the lack of observations in some areas gives a true indication of its range.
The timing of long-eared owl breeding in Scotland is influenced by food supplies. Typically birds use old nests, which are usually re-occupied from March. In years of plentiful small mammals the first eggs can be laid in late March, but mid-April is more normal, with up six eggs being produced. Incubation time ranges from 25-30 days, so most young hatch during May, although in good years this occurs in late April. Once young are three weeks old they are able to leave the nest by clambering and jumping. After four weeks they make their first faltering flights, though they remain dependent on the adults until around eight to nine weeks (Mikkola 1983).
Survey work during 1988-91 noted a widespread reduction in the breeding range of long-eared owl in Scotland ( New Atlas ), with breeding not recorded in 160 10km squares reported during a similar survey in 1968-72 ( Old Atlas ), and only 99 new 10km squares recorded. However, two factors make it difficult to be certain if this reflects a genuine decline. Firstly, there are fluctuations in breeding performance associated with the annual cycles of its main prey, which leads to variation in their detection; and, secondly, there is the lack of consistent recording effort that would allow changes to be detected. The results of the most recent Atlas will provide an interesting update on the status of this species in Scotland.
David C Jardine
Glue, D.E. and Hammond, G.J. (1974). Feeding ecology of the Long-eared Owl in Britain and Ireland. British Birds 67: 361-369.
Mikkola H. (1983). Owls of Europe. T.& A.D. Poyser, Calton.
Wooller, R.D. and Triggs, G.S. (1968). Food of the Long-eared Owl in Inverness-shire Bird Study 15: 164-166.
Hen Harrier• Goshawk• Sparrowhawk• Common Buzzard• Golden Eagle
Osprey• Kestrel• Merlin• Hobby• Peregrine Falcon• Barn Owl
Tawny Owl• Long-eared Owl• Short-eared Owl• Raven