BTO Surveys and Latest News

BTO in the Bristol Region

Many members of the BOC are also members of the British Trust for Ornithology (BTO), and many more contribute to their surveys.

Nationally we have reached 18,000 members and have 70,000 registered for our surveys, in Avon we have 337 members and 930 non members for our surveys, Garden Birdwatch ( 369 ) Breeding Bird Survey (184) WEBS (47) Swift & House Martins (73) and we would love to have more new members and volunteers .

The Regional Representative for the Bristol region (Avon) is Gordon Youdale (email: ).

Latest Local News

Current surveys

The BTO exists to gather accurate facts about bird populations and movements, and members share an enthusiasm for survey work which is second to none in the country. Below are a list of surveys currently taking place in the region – click a title to reveal more details.

Waterbirds on the Severn Estuary

We’re asking birdwatchers to look out for colour-ringed and dye-marked waders and ducks on and around the Severn Estuary.The British Trust for Ornithology and Wildfowl and Wetlands Trust have recently started a project to understand more about the home ranges of three species of waders (Curlew, Redshank and Dunlin) and a range of duck species on the Severn Estuary between Newport and Cardiff. Latest Blog at part of this work the Redshank and Curlew have been colour ringed and Dunlin and some ducks marked with yellow dye. In addition we have put state-of-the-art tracking devices on some of the Curlew, Redshank and Shelduck, which is giving us fascinating information about how birds use the estuary through the winter during both the day and the night. Work is ongoing, with the aim to mark more birds of these species and additional duck species during January and February.The work is funded by Tidal Lagoon Power, to provide high quality scientific information for the environmental impact assessment for a proposed tidal power lagoon (Tidal Lagoon Cardiff), and to inform their conservation and biodiversity programme – the Ecosystem Enhancement Programme (EEP).If you see any colour ringed or dyed birds when you are birdwatching either on the Severn or elsewhere, we would be very grateful for any sightings of these birds. We are particularly interested in any records of birds with yellow dye. Birds of different age have been marked on different parts of the body so please record the location of the dye and, if possible, the total number of birds in the flock, the date, time and location (ideally including a six-figure grid reference) alongside sightings of colour-marked birds. Any records of colour ringed birds on the Severn would also be extremely valuable and we will give all observers information on the history of any colour ringed birds. We are very keen to follow up any records quickly and would be grateful if you could phone the BTO on 01842 750050, or email Emily Scragg () with any records of colour-marked waders as soon as possible. Please email duck records to Ed Burrell (). Please pass on this information to any of your birdwatching contacts who may be interested in recording these birds. Further detail of the marking schemes is provided below:
Redshank have yellow over white colour rings on the left tarsus (below the “knee”), and a colour over a metal ring on the left tibia (above the “knee”), plus two colour rings on the right tibia.
Curlew have orange over white colour rings on the left tarsus, a single colour ring on the left tibia, the metal ring on the right tarsus and two colour rings on the right tibia.
Dunlin adults have yellow dye on the breast, while first-winter Dunlin have yellow dye on the undertail/flanks/rump.
Shelduck have yellow dye on the normally white plumage on the neck/upper breast.

Breeding Bird Survey

This survey began in 1994 and we monitor over 10% of the surface of the region, and can measure changes in common bird populations with precision. In 2010 125 observers spent 530 hours in 194 one-km squares counting 66,900 birds of 106 species.Take on a square, and you are hooked for life. If you are interested contact Dave Stoddard at

Garden Bird Watch

This survey is very widely supported in the region.The way the results are reported on the BTO website does not enable a summary of the Bristol region to be shown, but the large number of local supporters ensures that we play out part in establishing the local and national pattern of changes in garden use. The cold snap last December increased numbers using gardens by about 25%, and at one point most of the entire winter population of Redwings and Fieldfares were to be found in gardens, enabling these birds to survive. If you want to join contact Thenew Avon Ambassador is Jane Cumming –

Wetland Bird Survey

A small band of dedicated individuals survey the entire coast, and all major inland lakes in mid-month every month of the year. This survey was run by The Wildfowl and Wetland Trust until recently, and monitors all waterfowl and waders annually, and has done so since the 1950s. If you are interested contact or for sites on the coast contact Harvey Rose at .

Heronries Survey

As top predators in the freshwater food chain, herons are able to thrive only when their potential prey are also present in good numbers. Monitoring their breeding population sizes can therefore provide a valuable indicator of the health of the freshwater environment.
We have been annually counting Heron nests since 1928 making it the longest running bird survey and we would like all records for this species within Avon and now we have a New tutorials on how to use the online Heronries Census at:
The BTO Heronries Census collects nest counts of herons from as many heronries as possible in the UK each year. The main species covered is Grey Heron but Little Egret is fully included, as are rarer species of colonial herons such as Cattle Egrets (which nested in the UK for the first time in 2008). Nest counts of Cormorants are also collected, especially where they are nesting alongside herons. Data are shared with county recorders and for rare species with the Rare Breeding Birds Panel.

Owl Survey

Following on from the very successful BTO Owl Appeal, this year will be the start of our Project Owl research. With new surveys from autumn 2018, we need your help to learn more about our nation’s fascinating but often mysterious owl species. See Survey
Final Appeal for Surveyors –Final Appeal

Bird Track

This is a recording system common to the RSPB and BTO which also feeds into the Avon Bird Report and national databases. It provides those who use it with a permanent database of their records, and it measures with increasing accuracy the movement across the country of migrants both in spring and autumn, and also changes in distribution, because it is based on total counts of all species present during a bird walk. Visit for full details.


The Chew Valley Ringing Station provides around 2/3rds of the ringing data for the region and further information about ringing at the lake can be found at There are a number of other sites and individuals, in particular Peter Rock’s Gull ringing efforts which havehugely increased our understanding of Herring and Lesser Black-backed Gulls movements and population dynamics. Details about the birds ringed in the area, plus interesting recoveries, are given in the annual Avon Bird Report and can also be found on the British Trust for Ornithology’s website

Woodcock survey

Results of the latest survey for the South West indicates a reduction of 58.0% in breeding populations

Peregrine Survey

The table shows provisional estimates of the UK and IoM Peregrine population – shown as number of breeding pairs found in the 2014 survey.
Area20022014% change
Wales283249- 12
Scotland571509- 11
England470628+ 34
Isle of Man3123- 26
Northern Ireland8296+ 17
TOTAL14371505+ 5

Breeding Waders of Wet Meadows 2020 (Avon)

The purpose of this survey is to assess the importance of both existing and new wet grassland and other breeding wader habitats in England.
In total, nationally 2238 individual sites were reported as covered, consisting of 518 sites with Lapwing Plots, 71 with Agri-environment management. Then a further 1249 BW WM sites, which had been covered in 1982 and/or 2002. In Avon we were allocated 21 sites of which 62% were surveyed. The analysis is now underway, and we expect to have summary results available later in the winter.