The natural world range of Little Owls extends across Eurasia from Iberia to China's Yellow Sea and southwards from the Baltic to Mediterranean Africa with outlying populations elsewhere in Africa north of the equator. Fossil evidence shows that they existed in Great Britain in pre-historic times but by the modern era the species had died out here until it was re-introduced in the late 19th century. Much of southern lowland England provided the type of habitat in which they could thrive and by the 1950s they had spread throughout England and Wales and were beginning to appear in Scotland.
    In Wiltshire there were a few scattered records in the 19th century, assumed to be of escapes or failed introductions, but it wasn't until the first decades of the 20th century that they began to appear regularly. By 1920 they were reported to be established over the whole county, reaching a peak in the 1930s. Thereafter there was some overall decline nationally thought to have been caused by harsh winters in the 1940s and increased use of pesticides, before numbers stabilised in the 1970s. Numbers in Wiltshire remained stable from 1974 until the end of the century. Birds of Wiltshire recorded them present in 290 tetrads (32%), with breeding in 140 of them. Since then however there has been a sharp decline; WTA2 recorded their presence in only 152 tetrads with breeding in 72. This is consistent with the national trend recorded in Bird Atlas 2007-2011 which showed a decline in abundance in the south-western side of Britain, partly offset by increases in north-east and eastern England, possibly caused by changes in farming practices leading to decreased food supply.

References
The following references are used throughout these species accounts, in the abbreviated form given in quotation marks:
1968-72 Breeding Atlas” – Sharrack, J.T.R. 1976:  The Atlas of Breeding Birds in Britain and Ireland. T. & A. Poyser
1981-84 Winter Atlas” – Lack, P.C. 1986:  The Atlas of Wintering Birds in Britain and Ireland. T. & A. Poyser
1988-91 Breeding Atlas” – Gibbons, D.W., Reid, J.B. & Chapman, R.A. 1993: The New Atlas of Breeding Birds in Britain and Ireland 1988-91. T. & A. Poyser
Birds of Wiltshire” – Ferguson-Lees, I.J. et al. 2007 : Birds of Wiltshire, published by the tetrad atlas group of the Wiltshire Ornithological Society after mapping fieldwork 1995-2000. Wiltshire Ornithological Society.
Bird Atlas 2007-2011” – Balmer, D.E., Gillings, S., Caffrey, B.J., Swann, R.L., Downie, I.S. and Fuller, R.J. 2013: Bird Atlas 2007-2011: the Breeding and Wintering Birds of Britain and IrelandBirds of
WTA2” – ("Wiltshire Tetrad Atlas 2 ") the present electronic publication, bringing together the Wiltshire data from “Birds of Wiltshire” and “Bird Atlas 2007-11”, together with data from further fieldwork carried out in 2011 and 2012.
"Hobby" - the annual bird report of the Wiltshire Ornithological Society.