Why do we need RAS? Long-term monitoring of bird populations is needed in order to conserve them effectively. This tells us whether numbers are stable, decreasing or increasing. If there is a change ...

Marsh Tits and Willow Tits probably present one of the more difficult ID challenges in the UK. View our Bird ID video to gain some invaluable tips on key features to tell them apart.

Avian pox is caused by a virus, and sporadic cases of the disease are observed each year in British garden birds. Please note: avian pox is a different disease from avian influenza. Great Tit with ...

With its warm buff head and neck, black cap, grey back and deep chestnut shoulder patch, the adult Purple Heron is a smart bird, but one that favours the dense vegetation, such as reedbeds, of shallow ...

Explore how a particular species is faring in different countries, and download data and graphs with our interactive Trends Explorer. Search our index of the regularly occurring UK bird species listed ...

From donating, joining and fundraising to helping at events, volunteering for surveys, or becoming a corporate member, there are lots of ways you can support us and our work. Get involved in our ...

Each year, thousands of people from all over the UK kindly donate to BTO to help fund our research and monitoring of the UK's bird populations. The data and insight from our work provides crucial ...

Every donation makes a difference. Whether you make a monthly donation or give a one-off gift, support the area of our work that means the most to you. Please also see our past appeals page for more ...

Batten, L.A. 1978. The seasonal distribution of recoveries and causes of Blackbird mortality. Bird Study 25: 32. doi:10.1080/00063657809476571 ...

Identifying the two large sawbills, Goosander and Red-breasted Merganser, can be pretty straightforward when confronted with male birds. However, separating the females - or redheads, as they are more ...

Marchant, J.H. 1991. British Ornithologists' Union. Records Committee: Fifteenth Report (April 1991). Ibis 133: 441. doi:10.1111/j.1474-919X.1991.tb04594.x ...

Appleton, G.F., Adams, S.Y., Clark, J.A., Simons, J.R. & Peach, W.J. 1997. Report on bird ringing in Britain and Ireland for 1995. Ringing & Migration 18: 158.