BTO - British Trust for Ornithology - Climate change

Breeding Bird Survey

Anonymous — Fri, 02 Feb 2018 11:46:31 +0000

The Breeding Bird Survey is the main scheme for monitoring the population changes of the UK’s common and widespread breeding birds. The survey involves two early-morning spring visits to a 1-km square, to count all the birds you see or hear while walking two parallel 1-km lines across the square.

Breeding Bird SurveyButterfly Monitoring Friday, April 1, 1994 - 00:00

BBS monitors the population changes of 118 breeding bird species across the UK thanks to the dedication of almost 3,000 volunteers who survey their randomly selected 1-km square each spring.

The BTO/JNCC/RSPB Breeding Bird Survey (BBS) is the main scheme for monitoring the population changes of the UK’s common and widespread breeding birds, producing population trends for 118 bird and nine mammal species.

The survey involves a recce visit and two early-morning spring visits to an allocated 1-km square, to count all the birds you see or hear while walking two 1-km lines across the square and record any nest counts for colonial nesting birds in the square.

You can optionally record mammals and visit your square later in the season to survey for butterflies. There is the option to return data on paper, via field recording forms or to submit your data on BBS-Online.

Support the future of our birds

Our surveys are vital. The data they produce help us drive positive change for the UK’s birds.

But increased pressure on funding is putting our surveys and data at risk – which is why we need your support.

Donate today

bbs-report-2022-cover.jpg

Read the latest BBS report

The Breeding Bird Survey started in 1994, and a report is produced every year containing population changes and other results from the scheme.

The 2022 Breeding Bird Survey Report reveals a mixed picture, especially for birds which breed in farmland habitats.

Read the 2022 Breeding Bird Survey report

How to take part

Find out how to request a square and what the survey entails.

Results

Explore the results from the data BBS volunteers provide.

Mammal recording

Find out how to record mammals during your BBS visits.

Count butterflies on your BBS square

Take part in the Wider Countryside Butterfly Survey by making additional visits to your BBS square.

How to enter BBS data online

Instructions and video tutorials on submitting your BBS data.

Download BBS forms

Download and print BBS recording forms instructions and recording forms.

Support the future of our birds

Our surveys are vital. The data they produce help us drive positive change for the UK’s birds.

But increased pressure on funding is putting our surveys and data at risk – which is why we need your support.

Donate today

Take part in BBS - counting for conservation

David White

James Heywood

February – March Forms sent or downloaded
March Reconnaissance visit
Early April – mid May Early visit
Mid May – late June Late visit
May – August Wider Countryside Butterfly Survey
End of August Data entry deadline

Undertake three site visits between April and June - a recce and two morning visits, along with data entry. Able to identify UK breeding birds by sight, song and call. If you have the necessary bird ID skills to take part in the Breeding Bird Survey but want to learn more about survey methods, there are a number of BTO training courses covering this subject.

ongoing Farmland birdsUpland birdsWoodland birdsOther species volunteers

BTO Urban AppealWider Countryside Butterfly SurveyAssessing agri-environment schemes No bbs@bto.org

Mixed fortunes for UK’s herons and egrets

VIOLA.ROSS-SMITH — Fri, 02 Feb 2024 09:54:32 +0000

2024-05 02 Feb 2024

Surveys show colonising egrets and Spoonbills continuing to increase in many parts of the UK, while breeding Grey Herons seem slow in bouncing back following recent declines.

The British Trust for Ornithology (BTO) is marking World Wetlands Day (2 February) with the latest findings from its long-running Heronries Census. First launched back in 1928, the study set out to monitor and estimate the numbers of Grey Herons nesting in Britain. In recent years, the species covered in the census has grown as egrets and other waterbirds formerly restricted to the continent have colonised the UK’s wetlands, considered by many to be a direct result of climate change.

Little Egrets first nested in the UK in 1996 and over the past couple of decades they have been joined by Great White Egrets, Cattle Egrets and Spoonbills. Another bird covered by the census is the Cormorant, which has seen a change in nesting behaviour, with some birds now breeding inland in trees as opposed to on traditional coastal cliffs.

Grey Herons have shown ‘boom and bust’ population rises and dips since the census began almost a century ago, with temporary declines often associated with severe winters. However, the current reduction in breeding numbers is showing little sign of recovery and researchers are concerned that this familiar bird may be heading for the Birds of Conservation Concern Amber List.

Ian Woodward, Research Ecologist at the BTO said “This ongoing survey helps us monitor the overall well-being of nesting heron species across the UK. Thanks to the wealth of information gathered by our dedicated volunteers we can see just how these birds are responding both positively and negatively to changes in the environment.”

He continued “It also goes to show just how important the UK’s wetlands are as essential habitats for many of our resident species as well as those already colonising from the continent, such as Spoonbills, and those showing signs of doing so, such as Glossy Ibis.”

The Heronries Census is a valuable tool in the BTO’s research into the changes occurring within populations of wetland birds and more volunteers are being sought to help fill in some of the missing gaps.

Ian added “Many birdwatchers may be aware of new or small nesting colonies that haven’t yet been recorded by the census, and these could be vital in our understanding of how these species are adapting to change, or colonising new areas. The more information we can gather, the better we will understand just how our nesting herons and egrets are faring in an ever-changing landscape.”

Publication details

For further information about the BTO Heronries Census see here.

Images

Images are available for use alongside this News Release. These can be downloaded from this link for which you will need to enter the password 202405heron. Alternatively, please contact press [at] bto.org quoting reference 2024-05.

Spatially targeted nature-based solutions can mitigate climate change and nature loss but require a systems approach

VIOLA.ROSS-SMITH — Thu, 01 Feb 2024 17:06:10 +0000

The Cuckoo cohort of 2024 takes flight!

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Finch, T., Bradbury, R.B., Bradfer-Lawrence, T., Buchanan, G.M., Copping, J.P., Massimino, D., Smith, P., Peach, W.J. & Field, R.H. One Earth 10.1016/j.oneear.2023.09.005

Finite land is under pressure to provide food, timber, human infrastructure, climate change mitigation, and wildlife habitat. Given the inherent trade-offs associated with land-use choices, there is a need to assess how alternative land-use trajectories will impact the delivery of these benefits. Here, we develop nine exploratory, climate change mitigation-driven land-use scenarios for the UK. The scenario that maximized deployment of nature-based solutions reduced greenhouse gas (CO2e) emissions from the land sector by 100% by 2050 but resulted in a 21% decline in food production. All mitigation scenarios delivered aggregate increases in habitat availability for 109 bird species (including 61 species of conservation concern), although farmland-associated species lost habitat. Our study reiterates the potential of nature-based solutions to address global climate and biodiversity challenges but also highlights risks to farmland wildlife and the importance of food system reform to mitigate potential reductions in primary food production.

This study was funded by the Royal Society for the Protection of Birds (RSPB) and Natural England (project code ECM 58632). The Breeding Bird Survey is a Partnership between the BTO, RSPB, and Joint Nature Conservation Committee (on behalf of Natural Resources Wales, Natural England, Council for Nature Conservation and Countryside, and NatureScot) and relies on volunteer surveyors.

Avian responses to climate extremes: insights into abundance curves and species sensitivity using the UK Breeding Bird Survey

VIOLA.ROSS-SMITH — Wed, 31 Jan 2024 13:32:31 +0000

The Cuckoo cohort of 2024 takes flight!

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Tirozzi, P., Massimino, D. & Bani, L. Oecologia 10.1007/s00442-023-05504-9 Climate change remains one of the most urgent challenges for biodiversity conservation. Recent studies have highlighted that climate extremes (CLEXs) can lead to widespread and negative efects across all taxa and ecological levels, but most of these studies are based on short-term periods and small spatial scales and lack a multi-species approach. Here, using generalised additive models (GAMs) and the UK Breeding Bird Survey (BBS), we described response curves for the abundance of 100 resident bird species over large spatial and temporal scales and identifed the species showing a greater sensitivity to CLEXs. We used fve climatic indices computed at 1-km spatial resolution as proxies of CLEXs during the winter or breeding season and considered both 1- and 2-year lagged efects. The results demonstrated widespread and signifcant efects of CLEXs on bird abundances at both time lags and in both seasons. Winter frost days (FD0), summer days (SU25) during the breeding season and simple precipitation intensity index (SDII) during the breeding season mainly showed negative efects. Daily temperature range (DTR) in both winter and breeding season and dry days (DD) during the breeding season led to diversifed responses across the species, with a prevalence of positive efects. A large proportion of species showed a high sensitivity to CLEXs, highlighting that these species may deserve attention in future studies aimed at biodiversity conservation. We demonstrated that CLEXs can represent a signifcant driver afecting population abundances over large spatial and temporal scales, emphasising the need for understanding mechanistic processes at the basis of the observed efects. The authors thank all surveyors who have taken part in the Breeding Bird Survey, a partnership funded by the British Trust for Ornithology, Royal Society for the Protection of Birds and Joint Nature
Conservation, with feldwork conducted by volunteers.

Climate change and migratory species: a review of impacts, conservation actions, indicators and ecosystem services.

MIKETOMS — Fri, 08 Dec 2023 11:02:29 +0000

The Cuckoo cohort of 2024 takes flight!

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Williams, J.M., Scott, S.E., Galbraith, C.A., Martay, B., Macphie, K.H., Hereward, H.F.R., Barton, M.G., Bowgen, K.M., Pearce-Higgins, J.W. & Robinson, R.A. 978-0-86139-000-7 The study ‘Climate change and migratory species: a review of impacts, conservation actions, indicators and ecosystem services’ was commissioned by the Government of the United Kingdom of Great Britain and Northern Ireland through the Joint Nature Conservation Committee (JNCC) as a major contribution to the work of CMS on climate change and prepared by the British Trust for Ornithology (BTO).

Seabird abundances projected to decline in response to climate change in Britain and Ireland

VIOLA.ROSS-SMITH — Tue, 05 Dec 2023 11:57:57 +0000

The Cuckoo cohort of 2024 takes flight!

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Davies, J.G., Humphreys, E.M., Evans, T., Howells, R., O’Hara-Murray, R. & Pearce-Higgins, J.W. Marine Ecology Progress Series 10.3354/meps14462

Estimating species’ vulnerability to climate change is a key challenge in conservation. Many seabird species are particularly sensitive to negative effects of warming and are thus threatened by climate change. We projected seabird abundance in 2050 in Britain and Ireland, an internationally-important region for seabirds, under climate change scenario RCP8.5. Our projections were based on fitted relationships between abundance and both climatic (air temperature, precipitation) and oceanographic (sea surface temperature, potential energy anomaly) variables, estimated using a Bayesian hurdle model with spatial random effects. The most consistent responses to environmental variables were negative relationships between species presence or abundance and breeding season maximum terrestrial air temperature. Although data and modelling issues meant that future projections could be made for only 15 of the 25 species and with low predictive power for spatial abundance, predictive power was high for spatial presence and moderate for temporal abundance change. Projections suggest that seabirds will generally fare poorly under climate change in Britain & Ireland, with 10 species projected to decline in abundance by 2050. Variable model fit and projection uncertainty limited confidence, which was generally greater for declines than for increases. Fulmar, puffin and Arctic tern were each projected to decline by over 70% with higher confidence. For a few species, colonisation of new areas may reduce projected losses, but this is potentially limited by suitable habitat. Projected abundance change was more negative for marine specialists than for generalists. Our findings highlight the vulnerability and conservation needs of seabirds in a changing climate.

This paper was supported by funding from gifts in Wills to the BTO, for which the authors are extremely grateful. This paper is an output from the Marine Protected Areas Management and Monitoring (MarPAMM) project; the authors thank the project steering group for useful feedback at all stages of the development of the study and Naomi Wilson for the financial administration of the project on behalf of Agri-Food and Biosciences Institute (AFBI). This project has been supported by the EU’s INTERREG VA Programme, managed by the Special EU Programmes Body (SEUPB).

Linking climate warming and land conversion to species’ range changes across Great Britain

VIOLA.ROSS-SMITH — Mon, 06 Nov 2023 10:29:10 +0000

The Cuckoo cohort of 2024 takes flight!

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Suggitt, A.J., Wheatley, C.J., Aucott, P., Beale, C.M., Fox, R., Hill, J.K., Isaac, N.J.B., Martay, B., Southall, H., Thomas, C.D., Walker, K.J. & Auffret , A.G. Nature Communications 10.1038/s41467-023-42475-0 Although increased temperatures are known to reinforce the effects of habitat destruction at local to landscape scales, evidence of their additive or interactive effects is limited, particularly over larger spatial extents and longer timescales. To address these deficiencies, we created a dataset of land-use changes over 75 years, documenting the loss of over half (>3000 km²) the semi-natural grassland of Great Britain. Pairing this dataset with climate change data, we tested for relationships to distribution changes in birds, butterflies, macromoths, and plants (n = 1192 species total). We show that individual or additive effects of climate warming and land conversion unambiguously increased persistence probability for 40% of species, and decreased it for 12%, and these effects were reflected in both range contractions and expansions. Interactive effects were relatively rare, being detected in less than 1 in 5 species, and their overall effect on extinction risk was often weak. Such individualistic responses emphasise the importance of including species-level information in policies targeting biodiversity and climate adaptation. The authors thank the many thousands of volunteer surveyors of land use and biodiversity, without whom these analyses would not have been possible. Data and imagery from the Land-Utilisation Survey of Great Britain are reproduced with permission of the copyright holder Giles N. Clark. Chris Fleet at National Library of Scotland provided assistance with land-use maps covering Scotland, and Natural England provided assistance with maps covering England and Wales. This work was supported by a UKRI Natural Environment Research Council grant (NE/M013030/1, for A.J.S., J.K.H. and C.D.T.), a Northumbria University Vice Chancellor’s Senior Research Fellowship (for A.J.S.), and grants from the Swedish Research Councils Formas and VR (2015-1065 and 2020-04276, for A.G.A.).

Combining remote sensing and tracking data to quantify species’ cumulative exposure to anthropogenic change

VIOLA.ROSS-SMITH — Tue, 10 Oct 2023 09:15:21 +0000

The Cuckoo cohort of 2024 takes flight!

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Buchan, C., Gilroy, J.J., Catry, I., Hewson, C.M., Atkinson, P.W. & Franco, A.M.A Global Change Biology 10.1111/gcb.16974 Identifying when and where organisms are exposed to anthropogenic change is crucial for diagnosing the drivers of biodiversity declines and implementing effective conservation measures. Accurately measuring individual-scale exposure to anthropogenic impacts across the annual cycle as they move across continents requires an approach that is both spatially and temporally explicit—now achievable through recent parallel advances in remote-sensing and individual tracking technologies. We combined 10 years of tracking data for a long-distance migrant, (common cuckoo, Cuculus canorus), with multi-dimensional remote-sensed spatial datasets encompassing thirteen relevant anthropogenic impacts (including infrastructure, hunting, habitat change, and climate change), to quantify mean hourly and total accumulated exposure of tracked individuals to anthropogenic change across each stage of the annual cycle. Although mean hourly exposure to anthropogenic change was greatest in the breeding stage, accumulated exposure to changes associated with direct mortality risks (e.g., built infrastructure) and with climate were greatest during the wintering stage, which comprised 63% of the annual cycle on average for tracked individuals. Exposure to anthropogenic change varied considerably within and between migratory flyways, but there were no clear between-flyway differences in overall exposure during migration stages. However, more easterly autumn migratory routes were significantly associated with lower subsequent exposure to anthropogenic impacts in the winter stage. Cumulative change exposure was not significantly associated with recent local-scale population trends in the breeding range, possibly because cuckoos from shared breeding areas may follow divergent migration routes and therefore encounter very different risk landscapes. Our study highlights the potential for the integration of tracking data and high-resolution remote sensing to generate valuable and detailed new insights into the impacts of environmental change on wild species. The BTO Cuckoo Tracking Project was funded by the A. G. Leventis Foundation, BBC Wildlife Fund, Dulverton Trust, BTO including from much appreciated gifts in Wills, Ernest Kleinwort Charitable Trust, Essex and Suffolk Water, Mark Constantine, Tobit Trust and ‘Cuckoo Sponsors and Champions’. The authors thank everyone who provided assistance in the field, Paul and Russell Howey for assistance with PTTs, and BTO Fundraising and Communications teams for vital contributions to the project. CB was funded by a PhD studentship from the Natural Environment Research Council, grant number NE/L002582/1. IC was funded by contract 2021.03224.CEECIND from FCT (Fundação para a Ciência e Tecnologia).

The phenology and clutch size of UK Blue Tits does not differ with woodland composition

MIKETOMS — Fri, 25 Aug 2023 08:49:47 +0000

The Cuckoo cohort of 2024 takes flight!

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Branston, C.J., Whittingham, M.J., Phillimore, A.B., Leech, D. & Willis, S.G. Ibis 10.1111/ibi.13248

The deciduous tree-herbivorous caterpillar-insectivorous bird food chain is a well-studied system for investigating the impacts of climate change across trophic levels. To date, across Europe, most attention has focused on the impacts of increasing spring temperature on changes to phenology in oak-dominated (Quercus spp.) woodlands. Paridae species and Pied Flycatcher Ficedula hypoleuca are the most studied secondary consumers, all of which demonstrate an advancement in reproductive phenology with increases in spring temperature.

Shifts in climate and phenology may also impact on reproductive investment in clutch size, and the effects of climate on phenology and clutch size may vary depending on woodland composition. To date, the effects of among-habitat variation in phenology and reproductive investment have received little attention. Insectivorous birds inhabiting woodlands that differ in tree composition may differ in the timing of breeding, due to local tree leafing phenology acting as a cue for egg-laying date and/or clutch size. Moreover, for most insectivorous birds, woodland composition within a territory is likely to be the main determinant of food availability for both adults and chicks. Consequently, if warming springs affect the temporal patterns of food availability differently across different woodland compositions, this may affect the optimal average local phenology for nesting birds.

Here, using data from 34 long-term (mean 15 years) nest monitoring sites across the UK, we investigate the effect of woodland tree composition and temperature on Blue Tit Cyanistes caeruleus first egg date (FED) and clutch size. We supplemented the nest monitoring data by quantifying woodland composition, at a site level, through modified point counts.

We predict that birds breeding in woodlands with greater proportions of late-leafing species, such as oak and Ash Fraxinus excelsior, will breed later than those breeding in woodlands with greater proportions of early-leafing species, such as birch Betula spp. and Beech Fagus sylvatica. We found no evidence for differences in Blue Tit FED or clutch size in relation to the proportion of any of the tree species investigated, after controlling for temperature and latitude (FED: −3.4 and 2.2, clutch size: −0.4 and − 0.2 eggs for one-unit increase in temperature and latitude, respectively).

In recent decades and across all sites, clutch size has decreased as spring temperatures have increased, a strategy which could allow birds flexibly to adjust their breeding phenology such that nestling demand coincides with peak food availability. The lack of an effect of woodland composition on Blue Tit phenology suggests Blue Tits do not fine-tune their reproductive phenology to the local tree composition. Whether this lack of evidence for phenological divergence is due to an absence of divergent selection on breeding phenology and clutch size or to gene flow is not clear.

We would like to thank Roger Peart, David Warden, Stuart Downhill, RSPB and their many volunteers, Terry Fenton, Garth Lowe, Ros and John Matthews, John Bebbington, Dave Francis, Mischa Cross, Adam Homer, John Lawton Roberts, Peter Coffey, David Norman, Merseyside Ringing Group, Anne Goodall, Ian Spence, Joseph Carroll, Treswell Wood IPM Group, Chris du Feu, Lancaster District Birdwatching Group, John Wilson, Kevin Briggs, Jill Warwick, C. H. Fletcher, Geoff Myers and Tom Dewdney for collecting the bird nesting data and allowing access to their sites to collect additional habitat data. We would also like to thank David Branston and Harriet Clewlow for assistance in the field, and two anonymous reviewers for their thoughtful comments, which greatly improved the manuscript. The Nest Record Scheme is funded by a partnership of the BTO and the JNCC on behalf of the statutory nature conservation bodies (Natural England, Natural Resources Wales, NatureScot and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland).

Local colonisations and extinctions of European birds are poorly explained by changes in climate suitability

VIOLA.ROSS-SMITH — Wed, 16 Aug 2023 16:13:47 +0000

The Cuckoo cohort of 2024 takes flight!

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Howard, C., Marjakangas, E.-M., Morán-Ordóñez, A., Milanesi, P., Abuladze, A., Aghababyan, K., Ajder, V., Arkumarev, V., Balmer, D.E., Bauer, H.-G., Beale, C.M., Bino, T., Ali Boyla, K., Burfield, I.J., Burke, B., Caffrey, B., Chodkiewicz, T., Del Moral, J.C., Dumbovic Mazal, V., Fernández, N., Fornasari, L., Gerlach, B., Godinho, C., Herrando, S., Ieronymidou, C., Johnston, A., Jovicevic, M., Kalyakin, M., Keller, V., Knaus, P., Kotrošan, D., Kuzmenko, T,, Leitão, D., Lindström, Å., Maxhuni, Q., Mihelič, T., Mikuska, T., Molina, B., Nagy, K., Noble, D., Jostein Øien, I., Paquet, J.-Y., Pladevall, C., Portolou, D., Radišić, D., Rajkov, S., Rajković, D.Z., Raudonikis, L., Sattler, T., Saveljić, D., Shimmings, P., Sjenicic, J., Šťastný, K., Stoychev, K., Strus, I., Sudfeldt, C., Sultanov, E., Szép, T., Teufelbauer, N., Uzunova, D., van Turnhout, C.A.M., Velevski, M., Vikstrøm, T., Vintche Nature Communications 10.1038/s41467-023-39093-1 Climate change has been associated with both latitudinal and elevational shifts in species’ ranges. The extent, however, to which climate change has driven recent range shifts alongside other putative drivers remains uncertain. Here, we use the changing distributions of 378 European breeding bird species over 30 years to explore the putative drivers of recent range dynamics, considering the effects of climate, land cover, other environmental variables, and species’ traits on the probability of local colonisation and extinction. On average, species shifted their ranges by 2.4 km/year. These shifts, however, were significantly different from expectations due to changing climate and land cover. We found that local colonisation and extinction events were influenced primarily by initial climate conditions and by species’ range traits. By contrast, changes in climate suitability over the period were less important. This highlights the limitations of using only climate and land cover when projecting future changes in species’ ranges and emphasises the need for integrative, multi-predictor approaches for more robust forecasting.