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 342 members and 787 non members for our surveys, Garden Birdwatch ( 674 ) Breeding Bird Survey (122) and we would love to have more new members and volunteers .
Visit the BTO website for more information , training courses etc.
Participating in surveys is both rewarding and educational. It gives your birdwatching a different focus and helps you develop new skills, such as counting individual birds and using maps to plot their locations. At the same time, you are helping to gather valuable data to help us understand how birds are faring and what can be done to help them.
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.

Winter Gull Survey (WinGS) for 2023/24–2024/25

The last survey took place from 2003/04-2005/06 and concluded that the UK and near-shore coastal waters supported over 3.8 million wintering gulls at that time. Population trends from the BTO/RSPB/JNCC Wetland Bird Survey (WeBS) for gull species present in the UK in winter are variable and updated information is
necessary to identify potential Sites of Special Scientific Interest (SSSIs) and Special Protection Areas (SPAs) for gulls.
The primary goal of the survey is to produce new population estimates for wintering gulls in the UK and assess how populations have changed since the last survey in 2003/04–2005/06. The results of this survey will also aid us in assessing the impact of the ongoing outbreak of Highly Pathogenic Avian Influenza (HPAI) on gull populations and enable us to identify sites where the 1% threshold for the population is exceeded to thus recommend potential protected area designation for the species.
Surveys will be conducted in mid-winter 2023/24 and 2024/25. Further information will be collected in autumn 2024 which will mean that we can compare numbers across seasons for the first time.
WinGS Online is here! The survey webpage is now open to the general public. The vacant site map will accept volunteer requests for sites  and the organiser will have the function to assign volunteers to cover sites.
Please log in to your BTO account and sign up for WinGS, listed amongst other BTO surveys here:   if you have not got an account just sign up for one.
After you sign up it may take a few minutes for the survey to appear under “My Current Projects”. Please refresh your browser after signing up if you encounter a longer wait time, then follow instruction to view map and select a site you would like to survey.

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 14% of the surface of the region, and can measure changes in common bird populations with precision. 2022 was our most successful year to date with a total of 248 squares surveyed and 74,509 birds recorded and rather a relief after the difficulties of the previous couple of years. This terrific achievement was only possible thanks to your efforts. The National BBS is a vital conservation tool, measuring the changes in our breeding bird populations, particularly the commoner birds of town and countryside which can otherwise be easily overlooked. With the considerable additional help of our ‘Local’ squares we are also able to gain a much better understanding of our own local bird populations, producing trends for 30 species in Avon in 2022. Thank you very much for all your efforts in 2022 which are important and valued. Take on a square, and you are hooked for life.
 If you are interested contact Dave Stoddard or Peter Bryant who is taking over as BBS organiser for the 2023 season at    

Avon Winter Bird Survey

We will once more be running a Winter Bird Survey in Avon this coming winter for the eighth consecutive year and I hope that you will be able to participate again
The aim of the Survey is to measure the fortunes of the more common wintering species of the Avon BTO Region in the same way that the Breeding Bird Survey (BBS) has done so successfully for our breeding birds. Please find attached the Instructions and forms for the Survey.
Last year 2022 we covered a record total of 161 squares in the Avon BTO Region, our best performance to date, and recorded a total of 66,273 birds.
As last year the Survey will consist of a minimum of two visits – with one in November-December and one in January-February and with at least a four-week gap between visits. However, there is the option of doing a third visit in either Nov-Dec or Jan-Feb. This is entirely optional. However, please do still leave at least a four-week gap between visits. Any BBS square whether ‘National’ or ‘Local’ can be covered. Non-BBS squares can also be covered but please check with me to ensure that the square is not already allocated.
I hope that you will be able to participate in the Survey this coming winter – we are now building up a useful body of data on our ‘winter birds’.
If you will not be able to participate this season please let me know.
Dave Stoddard email;-

[toggle title="Garden Bird Watch"]
Help with research into garden wildlife by joining our Garden BirdWatch community. BTO has run the year-round Garden BirdWatch scheme since 1995, and thousands of people across the UK contribute their sightings each week. Gardens are really important habitats for wildlife, but we need to understand how and why populations of garden birds and other wildlife are changing, and how we can help them. You can help by keeping a simple list and telling us which species visit each week, helping us learn about how wildlife uses the food, shelter and other resources in our gardens. The more we can understand about how birds and animals use our gardens, the more we can improve our cities, towns, villages and individual gardens for wildlife. This survey is free to join and  is very widely supported in the region with 674 BTO members or  non members taking part in this important survey. 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.  If you want to join contact The new Avon Ambassador is Jane Cumming – email

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.

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.

Bird Ringing

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 with 38 bird ringers within Avon, in particular Peter Rock’s Gull ringing efforts which have hugely 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

Initial Results : Up to 2013 showed that counts were relatively stable until 2008. The number of Roding males then declined steadily until 2015. In 2016 there was a substantial increase, giving the highest counts since 2008 – but numbers then reduced in 2017, stabilised, and declined again in 2020. In 2021 and again in 2022, numbers increased slightly, but the overall trend is for decline. We await the latest results for the 2023 survey

Breeding Waders of Wet Meadows 2020 (Avon)

The purpose of this survey was 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.