BTO publishes various reports, from those covering the annual results of core surveys, through scientific studies, and on to those produced in partnership with other organisations. Many of these are published as BTO Research Reports. You can access all of our reports from here, though note that we are currently updating the reports section, working backwards through time to bring all of the report pages into a consistent format. You can read our Annual Report and Accounts in the Governance section.
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Northern Ireland Seabird Report 2023
The report includes detailed information about the population trends and breeding success of seabirds in Northern Ireland, over the 2023 breeding season. Notably, Fulmar and Kittiwake populations are reported to be experiencing continued declines, while Guillemot, Common Gull and Herring Gull populations show increases at most breeding sites.
15.04.24
Reports
BirdTrends 2023
The BirdTrends 2023 report is a one-stop shop for authoritative information about the population status of the common breeding birds of the wider UK countryside. The report is based on data gathered by the many thousands of volunteers who contribute to BTO-led surveys.Previous BirdTrends reports, up to and including BirdTrends 2022, included species pages displaying the latest information on trends in population size, breeding performance and survival rates for 121 species, as measured by our long-term monitoring schemes.The species information contained in previous BirdTrends reports has now been incorporated into BirdFacts, which provides a one-stop, easy-access location to review all the existing knowledge that is available about all the species found in the UK.However, the BirdTrends report itself continues to provide an overall summary of current trends in more than 120 UK bird species and is designed to be used in conjunction with the BirdFacts species pages.Download PDF
27.03.24
Reports
Modelling population-level impacts of wind farm collision risk on Welsh Red Kites
The Welsh Red Kite population is currently in ongoing recovery after a historic decline driven by persecution, and a consequent population bottleneck during the first half of the 20th century. Trends from the BTO/JNCC/RSPB Breeding Bird Survey show that the population has grown rapidly over the past few decades. Nonetheless, the Red Kite remains a conservation concern, in particular around two Special Protection Areas (SPAs) designated for the species’ conservation: the Berwyn SPA and the Elenydd—Mallaen SPA.Wind turbines represent a known threat to Red Kite populations, causing additional mortality through collisions. A large number of wind farm sites are currently at various stages of development (ranging from aspirational schemes to proposals under assessment) in Wales, especially in Mid Wales where Red Kites are at their highest density and where the Elenydd-Mallaen SPA is situated.The aim of this analysis is to model the potential impacts of current and proposed wind farm developments on the Welsh population of Red Kites, using a Population Viability Analysis.
15.03.24
Reports
Breeding periods of hedgerow-nesting birds in England
Hedgerows form an important semi-natural habitat for birds and other wildlife in English farmland landscapes, in addition to providing other benefits to farming. Hedgerows are currently maintained through annual or multi-annual cutting cycles, the timing of which could have consequences for hedgerow-breeding birds.The aim of this report is to assess the impacts on nesting birds should the duration of the management period be changed, by quantifying the length of the current breeding season for 15 species of songbird likely to nest in farmland hedges. These species are Blackbird, Blackcap, Bullfinch, Chaffinch, Dunnock, Garden Warbler, Goldfinch, Greenfinch, Linnet, Long-tailed Tit, Robin, Song Thrush, Whitethroat, Wren and Yellowhammer.
05.03.24
Reports
Bailiwick Bat Survey: 2023 season report
This report presents the main findings from survey work delivered using passive acoustic monitoring devices deployed across the Bailiwick of Guernsey.
26.02.24
Reports
Climate change and migratory species: a review of impacts, conservation actions, indicators and ecosystem services.
This major report, prepared by BTO staff and colleagues at JNCC, surveys the evidence on the impacts of climate change on migratory species. It was launched on 10 December 2023 at the UN Climate Change Conference in Dubai (UNFCCC COP28).
Available from the JNCC website
10.12.23
Reports
Ryevitalise - Bats and Ancient Trees, 2023 Report
Working with a network of volunteers, static acoustic bat detectors were deployed over a long survey season, to provide the fourth season of extensive bat data for the Ryevitalise Landscape Partnership Scheme area of the North York Moors National Park. This report provides an overview of the survey coverage and main results from 2023.
05.12.23
Reports
Scottish Raptor Monitoring Scheme Annual Report 2021 & 2022
01.12.23
Reports
Analysis of Wetland Bird Survey (WeBS) data for The Humber Estuary SSSI, SAC, SPA and Ramsar site: fourth appraisal — sector-level trends to winter 2021/22
This study updates previous reports that assessed population trends of waterbird species in different parts of the Humber Estuary, in order to identify areas where species were declining contrary to, or in excess of, the trend for the Humber Estuary as a whole and, furthermore, to identify sectors that support an increasing proportion of species that are declining across the Humber Estuary as a whole.
01.12.23
Reports