Contents of report
Breeding Bird Survey
Common Birds Census
Constant Effort Sites
Nest Record Scheme
Waterways Bird Survey
What the categories mean
Return to BTO Home Page
Conservation Listings Long term trend

Biodiversity Steering Group Conservation Concern List

UK: Unknown

Status Summary
This is one of the most poorly monitored UK species, being very secretive and nocturnal. Only brood size is recorded in sufficient numbers for this species, and indicates no trend over time. Its distribution appears to have decreased markedly but for unknown reasons (Gibbons et al. 1993).
Annual breeding population changes for this species
are not currently monitored by BTO
Table of productivity information for Long-eared Owl
Variable Period
Years Mean
Trend Predicted
in first year
in last year
Change Comment
Brood size 30 1968-1998 10 None       Small sample
Insufficient data on clutch size
available for this species

Insufficient data on egg failure
available for this species
Insufficient data on nestling failure
available for this species

Insufficient data on laying date
available for this species


Insufficient data on CES
available for this species




The report should be cited as: Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Bashford, R.I., Beaven, L.P., Freeman, S.N., Marchant, J.H., Noble, D.G., Raven, M.J., Siriwardena, G.M., Thewlis, R. and Wernham, C.V. (2001) Breeding Birds in the Wider Countryside: their conservation status 2000. BTO Research Report No. 252. BTO, Thetford. (

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Last updated: 17 April, 2001

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