Британское орнитологическое общество: история и исследования птиц

The British Trust for Ornithology (BTO) is an organisation founded in 1932 for the study of birds in the British Isles. The Prince of Wales has been patron since October 2020.

In 1938 the BTO contributed funds to the new Edward Grey Institute of Field Ornithology. In 1947, the institute became part of a new department of Zoological Field Studies at the University of Oxford, and the BTO again concentrated on a programme of volunteer based surveys.

In December 1962, at the behest of Tony Norris, the BTO purchased Beech Grove, a large Victorian house in Tring, Hertfordshire, relocating there from Oxford, along with their Ringing Office, which had been at the British Museum.

In April 1991, the BTO moved to The Nunnery, Thetford, Norfolk, a large property lying between the A134 and the River Little Ouse, which had been donated to them. Parts of the medieval Benedictine Nunnery of St George can still be seen on this site. The BTO also runs its only bird reserve, Nunnery Lakes Reserve, on this site. The reserve lies between the River Thet and the River Little Ouse, extending upstream from The Nunnery, along the banks of the Little Ouse, and incorporates several flooded gravel pits. In the early 2000s, a new library was created there, dedicated to the memory of Chris Mead. Professor Jeremy Greenwood PhD, who had been Director since 1988, retired in September 2007. The current Chief Executive Officer is Dr Juliet Vickery, as of 2020.

The BTO carries out research into the lives of birds, chiefly by conducting population and breeding surveys and by bird ringing, largely carried out by a large number of volunteers. Its Garden Birdwatch survey, for example, allows large numbers of birdwatchers to participate, by making a weekly count of the birds they see in their gardens.

In September 1967, inspired by on going work on the innovative Atlas of Breeding Birds of the West Midlands, produced by the West Midland Bird Club, and in partnership with the Irish Wildbird Conservancy (now BirdWatch Ireland), work began on the first Atlas of Breeding Birds in Britain and Ireland. 3,862 10 km squares were surveyed and the atlas was published in 1976. The New Atlas (1993) updated and refined this huge survey, again with the help of IWC and the Scottish Ornithologists Club. A Winter Atlas and a Historical Atlas have also been published. The groundbreaking Migration Atlas presents the results of almost 100 years of bird ringing. As with all BTO studies, the vast majority of the fieldwork was undertaken by volunteers. The Bird Atlas 2007–11, published November 2013, combines breeding and winter surveys across the entire UK and Ireland, involving the BTO, Birdwatch Ireland, and the Scottish Ornithologist's Club, in order to produce a new atlas. Fieldwork began in winter 2007, and was due to continue until the end of 2011.

The Trust awards the Bernard Tucker Medal for services to ornithology, named in memory of Bernard Tucker, the first Secretary, and the Dilys Breese Medal in honour of Dilys Breese and several Marsh Awards for Ornithology.

BirdTrack is an online citizen science website, operated by the BTO on behalf of a partnership of the BTO, the RSPB, BirdWatch Ireland, the Scottish Ornithologists' Club and the Welsh Ornithological Society (Cymdeithas Adaryddol Cymru).