Wild bird populations in the UK and England, 1970 to 2023
Updated 12 November 2024
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Key changes to the UK and England wild bird publication
Updates for this publication are:
- All chapters have been updated using the most recent data from 2023.
- This publication, which used to be two separate publications, one for the UK and one for England, has been merged this year. We are keen to seek feedback on this change, so please email your views to enviro.statistics@defra.gov.uk.
- We have updated the way we visualise overall species trends and present a breakdown of individual species trends for the first time. We would appreciate any feedback on the readability of these charts, which can be emailed to enviro.statistics@defra.gov.uk.
- We have updated the figures used in this statistics release, and introduced some new ones. We are keen to seek feedback on this change, so please email your views to enviro.statistics@defra.gov.uk.
- The statistical (bootstrapping) approach to generating confidence intervals used in indicators with a large and diverse suite of species can be sensitive to individual species with sparse data in periods of the time series. This can be seen in the widening of confidence intervals in the England indicator. The species composition of this indicator will be reviewed, and a sensitivity analysis performed to determine whether these species should be retained and to carefully consider what the impact of their removal would be.
- There are no confidence intervals available for seabird indicators for the 2024 publication, pending consultation on a recent thorough review of the analytical methods used in the Seabird Monitoring Programme (SMP) species population indices, including confidence estimation. New analytical approaches will be developed and tested, and when available, the resulting trends will be incorporated into the aggregate seabird indicators. Trends should be interpreted with care due to the relatively small number of species included in some indices and the scarcity of data for some constituent species.
- We have removed unsmoothed trends from our time series plots, with the exception of wintering waterbirds and seabirds (where there are no confidence intervals available). These unsmoothed trends will still be available in the accompanying datasheet.
- We no longer show breakdowns of England species trends, instead presenting the overall UK trends and noting where these differ. The underlying England data can still be found in the associated datasheet.
Summary
In 2023, the combined bird species indices for the UK and England continue to show an overall decline. Since 1970, the indicators have declined by 16% in both the UK and England. Both indicators declined most between the late 1970s and the early 1990s, driven mostly by steep declines in woodland and farmland birds. Those two indicators then remained relatively stable or showed shallow declines until the mid 2010s, before in recent years showing a slightly accelerated downward trend. In the UK, the all-species index declined by 2% in the short term (the 5 year period between 2018 and 2023). In England, this drop was much steeper, with a decline of the all-species index of 7% in the same period. This decline is particularly associated with steep short term declines observed in woodland and farmland birds, although with the exception of UK upland birds, UK seabirds and UK water and wetland birds, all bird groups show a decline in this period.
Throughout this publication, you will find chapters on:
- All-species chapter 1
- Farmland birds chapter 2
- Woodland birds chapter 3
- Water and wetland birds chapter 4
- Seabirds chapter 5
- Upland birds chapter 6
- Wintering waterbirds chapter 7
Introduction
Why monitor bird populations
Bird populations have long been considered to provide a good indication of the broad state of wildlife in the UK. This is because they occupy a wide range of habitats and respond to environmental pressures that also operate on other groups of wildlife. In addition, there are considerable long-term data on trends in bird populations, allowing for comparison between trends in the short term and long term. Because they are a well-studied taxonomic group, drivers of change for birds are better understood than for other species groups, which enable better interpretation of any observed changes. Birds also have huge cultural importance and are highly valued as a part of the UK’s natural environment by the general public. Although bird indicators can reflect the health of the natural environment more widely, those presented in this publication should not be used in isolation to infer the status of all other species groups.
It is not practical to determine changes in the actual number of birds for each species in the UK and England each year, but it is possible and to reliably assess the status of many species by calculating relative change, based on counts on representative sample plots surveyed as part of national monitoring schemes (see Main notes at the end for more details of the survey sources used).
Trends in bird populations are used by policy makers, government agencies and non-governmental organisations as part of the evidence base with which to assess the effects of environmental management, such as agricultural practices or woodland management, on bird populations. The trends are also used to assess the effectiveness of environmental interventions intended to address declines, such as agri-environment schemes targeted at farmland birds.
Understanding the bird population indices
Individual bird species population trends, based on carefully designed surveys undertaken largely by volunteer experts, are calculated as a series of annual indices. These relate the population in a given year to a ‘baseline’ – the first year that data are available – which is given a value of 100. Thereafter, the index is expressing the population as a percentage of this ‘baseline’.
This annual Defra Accredited Official Statistics Release presents data trends up to 2023 in populations of common birds (species with a population of at least 500 breeding pairs in the UK, or 300 breeding pairs in England) that are native to, and breed in, the UK, with trends overall as well as for 5 main habitat groups (see relevant data sets published alongside this update for a list of birds in each group). The release also presents trends up to 2022/2023 for wintering waterbird populations, some of which also breed in the UK. In each chapter there are species that are included in the overall indicator, but not the habitat breakdowns, or are present in multiple habitat breakdowns.
The charts presented combine individual species indices into a single indicator to provide an overall trend for each group mentioned above using a geometric mean - an average calculated by multiplying a set of index values and taking the nth root, where n is the number of index values. More information can be found in Introduction to the Wild Birds Population Indicator. The indices are considered to give reliable medium to long-term trends, but strong reliance should not be attached to short-term changes from year to year.
Assessing trends
Smoothed trends are referred to in the text, which are used to formally assess the statistical significance of change over time. Smoothed trends are used for both long and short-term assessments as they reduce the short-term peaks and troughs resulting from, for example, year-to-year weather and sampling variations as well as good or bad breeding seasons See analytical methods on BTO website (Fewster et al. 2000. Ecology 81: 1970-1984). The most recent data point in smoothed trends, that is, 2023 in this update, can change in subsequent publications due to the smoothing process being applied and to additional data included in future updates (see BTO Research Report on ‘Production of smoothed population trends when a year of data is missing’ on BTO’s ‘Bird Indicators’ web page). Results and estimates of change are based on smoothed indices but unsmoothed trends are also provided in the associated data sheets.
These trends are based on estimates from surveys. Smoothed trends are presented with 95% confidence intervals (CI), which are a measure of the precision of these survey estimates: a 95% CI means users can be 95% confident that the true change in abundance relative to the baseline year falls within the confidence interval around it. The width of the confidence intervals varies between habitat indicators because it is influenced by the number of species in each indicator and the precision of the individual species trends that make up the indicator. For the indicators derived from species trends that cannot be statistically evaluated by this method (wintering waterbirds and seabirds), a threshold is used to evaluate the significance of the change. For wintering waterbirds this threshold is set at 5%. For seabirds, for which there are more gaps and variability in the underlying data, the threshold is set at 10%.
Throughout this release, assessment periods are referred to as:
- ‘Long-term’ – an assessment of change since the earliest date for which data are available; this varies among indicators and among individual species.
- ‘Short-term’ – an assessment of change over the latest 5 years for which data are available.
The data sets published alongside this update show long-term and short-term assessments for each individual bird species. Individual species assessments are calculated up to the penultimate year of data to account for uncertainty in the final year estimate.
Alongside the overall index, the percentage of species within each indicator that have increased or decreased in the long-term and in the short-term is also shown. This is based on the average rate of annual change over the long or short-term, categorised by how much the population would change if that annual change continued for 25 years. These thresholds are asymmetrical to represent symmetrical proportional change in an index, that is, the opposite of a 50% decline is a doubling (a 100% increase), not a 50% increase. These thresholds are derived from those used in the Birds of Conservation Concern status assessment on the BTO website for birds in the UK.
The 5 categories of change are defined as:
- strong increase: population increase of 100% or more
- weak increase: more than 33% but less than 100% increase
- little change: between a 25% decrease and a 33% increase
- weak decline: less than 50% but greater than 25% decrease
- strong decline: population decrease of 50% or more
Although a species may be classed as little change based on their rate of annual change continuing over a 25 year period, over longer periods of time this can still represent a substantial population change. For example, over 50 years species in this category may have experienced a decline of 50% or an increase of 66%.
The bird population indices have been compiled in conjunction with the British Trust for Ornithology (BTO), the Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
1. Native breeding wild bird populations
All birds Indicator trend description
The ‘all bird species’ index has declined by 16% in both the UK and in England since 1970. Following an initial upturn, this has show a shallow decline between the mid 1970s and the early 1990s. The index then remained relatively stable until 2015, since when it has shown a modest but continuous decline, with the UK indicator declining by 2% and England by 7% in the 5 years since 2018. The overall decline observed in the all species indicators, each composed of more than 100 species trends, masks considerable variation in the different habitat indices and in individual species trends.
Figure 1.1: Populations of 130 wild bird species in the UK and 118 in England, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 1.1:
- The smoothed trends are shown together with the 95% confidence intervals (a measure of uncertainty) represented by the shaded area around each line on the chart.
- The statistical (bootstrapping) approach to generating confidence intervals used in indicators with a large and diverse suite of species can be sensitive to individual species with sparse data in periods of the time series. This can be seen in the widening of confidence intervals in the England indicator. The species composition of this indicator will be reviewed, and a sensitivity analysis performed to determine whether these species should be retained and to carefully consider what the impact of their removal would be.
- The lower confidence intervals for the England index in 1994 and 1995 were un-estimable, this is due to the high uncertainty around the population trend for Snipe which is a scarce species. As a result the lower confidence intervals on the graph abridges the two data points for 1993 and 1996.
Variation in habitat index trends
The variation observed in the index trends for different bird habitats is summarised in Figure 1.2 and Table 1, whilst the detailed habitat indices (including indices for the different subgroups within each habitat) are shown in the individual habitat sections later in this publication. A summary of each habitat is provided here:
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Farmland bird populations have declined severely (by around 61% over the long-term and 9% in the short term), with declines being stronger for farmland specialist birds than generalists. Examples of farmland birds in strong long-term decline includes turtle dove, grey partridge, tree sparrow, corn bunting and starling, although some (corn bunting for example) show small increases in recent years.
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Woodland bird populations have declined severely by around 35% over the long-term and 10% in the short term. Long term declines have been driven by woodland specialist birds but there has also been a sharp downturn in generalist birds over the past five years. Examples of woodland birds in strong long-term decline include willow tit, capercaillie, lesser spotted woodpecker and spotted flycatcher.
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Breeding water and wetland bird populations have experienced little to no change over both the long term and short term (except for England, where they declined by 7%). However, this masked considerable variation in the different habitats with, for example, birds in reedbed habitats increasing. Examples of breeding water and wetland birds in strong decline include yellow wagtail in the long-term and lapwing, coot and tufted duck in the short term.
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Seabird populations in the UK have declined in the long term (25%) and shows signs of stability in the short term. The England seabird index, which is comprised of a slightly different suite of species, shows little or no change in both the long and short term. Examples of seabirds in strong decline include Arctic skua (all UK birds are in Scotland) and herring gull.
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Upland bird populations in the UK have declined in the long term (7%) and experienced little to no change in the short term. In England, they have experienced little to no change throughout. Examples of upland birds in strong decline include peregrine falcon, redshank, and whinchat.
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Most Wintering waterbird trends are not included in the all bird species indicator as this indicator is based on wintering populations, whether or not there are also breeding populations in the UK. These wintering populations have increased markedly in the long term (90%), but this trend changed around 2000 and is now showing a steep short-term decline (8%). No wintering water birds are in strong decline long term, but over the short term examples include Bewick’s swan, scaup and Icelandic greylag goose.
Figure 1.2: Populations of wild birds in the UK and in England by habitat, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 1.2:
- The indicators are based on the aggregated population trends for each habitat and each country.
- Figure 1.2 shows the smoothed trend for all habitats together with the 95% confidence intervals (a measure of uncertainty) represented by the shaded area around each line on the chart.
- The wintering waterbirds data is not included in the ‘all species’ indicator as this index is based on wintering numbers, whether or not any of the species in it also have breeding populations in the UK.
Table 1: Long and short-term trends at a glance for the UK and England
Index | Time period | Number of Species (UK /England) | Long-term trend UK | Short-term trend UK | Long-term trend England | Short-term trend England |
---|---|---|---|---|---|---|
All bird species | 1970 to 2023 | 130 / 118 | Deteriorating | Deteriorating | Deteriorating | Deteriorating |
Farmland | 1970 to 2023 | 19 / 19 | Deteriorating | Deteriorating | Deteriorating | Deteriorating |
Seabirds | 1986 to 2023 | 13 / 11 | Deteriorating | Little or no change | Little or no change | Little or no change |
Upland | 1994 to 2023 | 32 / 28 | Deteriorating | Little or no change | Little or no change | Little or no change |
Wetland | 1975 to 2023 | 26 / 26 | Little or no change | Little or no change | Deteriorating | Deteriorating |
Wintering waterbirds | 1975/1976 to 2022/2023 | 46 / 40 | Improving | Deteriorating | Improving | Deteriorating |
Woodland | 1970 to 2023 | 37 / 34 | Deteriorating | Deteriorating | Deteriorating | Deteriorating |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends
The ‘all bird species’ index includes aggregated population trends for 130 species of birds in the UK and 118 for England. The species list is compiled using mainly widespread species which each have a population of at least 500 breeding pairs (or 300 in England), and have sufficient data to calculate a trend. Species trends vary widely, from species increasing several-fold in the long term (for example, Cetti’s warbler, avocet, blackcap, buzzard, great spotted woodpecker, red kite and collared dove) to those having declined to less than a tenth of 1970 numbers (for example, turtle dove, capercaillie, willow tit, grey partridge, tree sparrow and spotted flycatcher).
To summarise trends in individual bird species changes (long term and short term) we present bar charts showing the proportion of species that are increasing, in decline, or show little or no change.
- In the UK 30% of species have declined since 1970 and a similar percentage of species has increased (28%).
- The short term trends shows a higher percentage of species in decline (42%) compared to those increasing (28%).
Similar patterns are observed in England, except for a stronger short term decline of 49%.
Figure 1.3: Long-term (1970 to 2022) and short-term changes (2017 to 2022) in species trends for the All birds species indicators
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 1.3:
- The indicators are based on the aggregated population trends of 130 species of wild birds in the UK and 118 species in England.
- Each row represents 100% of the species within a habitat.
- Each stack within a bar shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Variation in individual species trends for different habitats
The all bird species trends also masks variation in individual species trend summaries of the different habitats, and we provide a detailed breakdown (including a breakdown of subgroups such as generalist and specialist bird species) in the habitat specific chapters. To highlight this variation, a comparative summary of the long term and short term trends for individual species for each habitat in the UK is presented below. The key results are:
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Widespread species decline across habitats: across all habitats, a significant percentage of species are in decline except UK wetlands over the long term, with farmland and marine habitats showing the highest proportions of declining species. The short-term trends continue to show declines, particularly in woodland and wintering waterbird species.
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Farmland and woodland species are under pressure: farmland species are particularly at risk, with the highest percentage of species in decline considering both time periods and relatively few in increase. Woodland species are also under significant pressure, especially in the short term, where more than half of all species are declining.
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Limited evidence of increase in species: Although in the all-species indicator the number of species increasing and decreasing in the long term is similar - a smaller percentage of species show increasing trends across most of the habitats, with the highest proportion of increasing species observed in wintering waterbirds in the long term and seabirds in the short term.
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Stability in certain habitats: across several habitats, a notable proportion of species show little or no change, including seabirds, woodland and upland, which includes nearly half of the species over the long term. Short term habitats showing a substantial proportion of species with little change include woodland, farmland and upland.
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A reversal in trend for wintering waterbirds: Over the long term, almost half of all wintering waterbird populations have increased, whereas the opposite trend is seen over the short term, with the same proportion now in decline.
In England, we see similar trends in the long term. Over the short term there are some notable differences:
- Wetland and woodland see the same percentage in decline, over two thirds of constituent species.
- They are closely followed by farmland and upland habitats, where around half of constituent species are in decline.
Figure 1.4: Long-term and short-term changes in individual species trends for different habitats in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 1.4:
- Each row represents 100% of the species within a habitat.
- Each stack within a bar shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
- Over the long term, 32 upland species were assessed but only 26 could be assessed over the short term.
- Habitats are ranked by highest percentage of species in decline.
- WWB: Wintering waterbirds.
2. Breeding farmland bird populations in the UK and England
Indicator trend description: Farmland birds
Farmland bird populations have declined by 61% since 1970. The most severe population declines occurred between the mid 1970s and the early 1990s, largely due to the negative impact of rapid changes in farmland management during this period. Although the rate of decline has slowed since this period, the populations have continued to decline at a fast rate, declining by 9% in the 5 years since 2018. The long-term decline of the farmland bird indicator in the UK has been driven mainly by the decline of those species that are restricted to, or highly dependent on, farmland habitats (the ‘specialists’). The remaining species included in the indicator are ‘generalists’. These generalist species have seen severe population declines since the mid 2000s, contributing to the fast decline observed in the farmland bird indicator over the same time period.
Farmland refers to the 70% of land in the UK and 67% of land in England which is devoted to agriculture. Farmland also provides semi-natural habitats such as hedgerows and field margins that provide food and shelter to birds.
Figure 2.1: Breeding farmland birds for 19 species in the UK and England, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 2.1:
- The indicators are based on the aggregated population trends of species of farmland birds in the UK and England (of which 12 species are farmland specialists and 7 are generalists).
- Figure 2.1 shows the smoothed trend together with its 95% confidence interval (a measure of uncertainty) represented by the shaded area on the chart, for the UK and England.
Figure 2.2: Breeding farmland birds by species group in the UK and England, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 2.2:
- The indicators are based on the aggregated population trends of 19 species of farmland birds in the UK and England (of which 12 species are farmland specialists and 7 are generalists).
- Figure 2.2 shows the smoothed trend together with its 95% confidence interval for the different subgroups of birds. Trends for the UK and England are plotted side by side.
Table 2: Long and short-term trends at a glance for Farmland birds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1970 to 2023 | 19 / 19 | -61% | -9% | -63% | -10% |
Generalists | 1970 to 2023 | 7 / 7 | -22% | -6% | -15% | -6% |
Specialists | 1970 to 2023 | 12 / 12 | -73% | -10% | -77% | -12% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Farmland birds
The farmland bird index for both the UK and England includes individual measures for 19 species of farmland birds, of which 12 species are farmland specialists and 7 species are farmland generalists. In the UK:
- 43% of generalists species have declined since 1970 and in the most recent 5-year period 57% of generalists species have declined
- 75% of specialist species have declined since 1970 and in the most recent 5-year period 33% of specialist species have declined
Similar trends are observed in England, with the exception that:
- in the long term fewer generalist species have declined in England (29%)
- in the most recent 5-year period more specialist species have declined (50%)
Figure 2.3: Long-term and short-term changes in species trends for farmland birds in the UK, 1970 to 2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 2.3:
- The indicators are based on the aggregated population trends of 19 species of farmland birds in the UK (12 species are farmland specialists and 7 species are farmland generalists).
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Farmland birds
Farmland generalists
The generalist species use a wider range of habitats than the specialist farmland species. Three generalist species have declined over the long-term period: greenfinch by 68%, yellow wagtail by 70% and kestrel by 52%. While numbers of rook and reed bunting have not changed enough to be designated as showing decline, populations of two species, woodpigeon and jackdaw, have more than doubled relative to 1970 levels.
In the short term time period one of the seven species, greenfinch, decreased strongly (by 20% in the UK and 19% in England), in this species attributed to the impact of the disease trichomoniasis.
Farmland specialists
Five farmland specialists (turtle dove, tree sparrow, grey partridge, corn bunting and starling) have experienced severe declines in excess of 80% since 1970. In contrast, numbers of two other farmland specialists (stock dove and goldfinch) have more than doubled over the same period, this shows how responses to changes in farmland or other factors vary among species.
In the short-term the index for farmland specialists shows that on average specialists declined by 10%. Turtle dove, has shown a marked change in numbers over this recent 5-year period, decreasing by 54% in the UK and in England. Tree sparrow also continue to decline sharply, by 25% (35% in England), whereas stock dove and corn bunting increased by 21% (26% in England) and 18% (20% in England) respectively since 2017.
Figure 2.4: Long-term and short-term changes in individual species trends for farmland birds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 2.4:
- Figure 2.4 shows the individual population trends of 19 species of farmland birds in the UK and in England (12 species are farmland specialists and 7 species are farmland generalists).
- Species names are labelled with the associated habitat specificity. G - farmland generalist species; S - farmland specialist species.
- Only those species for which the trend was significant and whose magnitude placed it outside of the ‘little or no change’ category are labelled with their percentage change.
- For visualisation purposes the axis have been truncated to between -100% and +100%. For species that exceed the +100% limit, the exact percentage change is labelled next to the bars and marked with a † symbol. In figure 2.4 woodpigeon, stock dove, jackdaw and goldfinch all exceed 100%.
Factors affecting farmland bird populations
Farmland refers to the 70% of land in the UK which is devoted to agriculture. Farmland also provides semi-natural habitats such as hedgerows and field margins that provide food and shelter to birds. The large declines in the abundance of many farmland birds have a number of known and potential causes. For a large part, declines have been caused by the changes in farming practices that have taken place since the 1950s and 1960s, such as the loss of mixed farming, a move from spring to autumn sowing of arable crops, change in grassland management (for example, a switch from hay to silage production), increased pesticide and fertiliser use, and the removal of non-cropped features such as hedgerows. The rate of these changes, which resulted in the loss of suitable nesting and suitable feeding habitats, and a reduction in available food, was greatest during the late 1970s and early 1980s, the period during which many farmland bird populations declined most rapidly. However, some generalist species such as woodpigeon have benefited from increased availability of their food throughout the winter owing to the autumn sowing of crops.
Some farming practices continue to have negative impacts on bird populations, but most farmers can and do take positive steps to conserve birds on their land. In particular, a number of incentive schemes encourage improved environmental stewardship in farming, with some measures specifically designed to help stabilise and recover farmland bird populations. These include the provision of over-wintered stubble and planted wild bird crop covers to provide seed in the winter, uncropped margins on arable fields and sympathetic management of hedgerows. There is growing evidence that such action can deliver local recoveries in farmland bird populations and thus, if delivered at appropriate scale, wider recovery. Changes in numbers experienced by some species may, to a lesser extent, be further driven by other pressures. For example, there is evidence of an adverse impact from disease for some species, most notably greenfinch.
For more information about the evidence for this indicator, see the evidence statement Annex 1.03 Evidence Statement for C5a Farmland Birds.
3. Breeding woodland bird populations in the UK and England
Indicator trend description: Woodland birds
Woodland bird populations have declined by 35% in the UK and 38% in England since 1970. The rate of decline has accelerated in the last decade, declining by 10% in the UK and 12% in England in the 5 years since 2018. The long-term decline of the woodland bird indicator in the UK has been driven mainly by the decline of those species that are restricted to, or highly dependent on, woodland habitats (the ‘specialists’). However, the increased rate of decline observed in the last 5 years has been driven by declines in populations of both the generalist and specialist species alike.
Woodland covers 13% of the UK’s land area and 10% of England’s, providing trees and other vegetation suitable for nesting, foraging opportunities and cover from predators.
Figure 3.1: Breeding woodland birds for 37 species in the UK and 34 in England, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 3.1:
- The indicators are based on the aggregated population trends of species of woodland birds in the UK and England, of which 25 species are woodland specialists (22 in England) and 12 are generalists in the UK and England.
- Figure 3.1 shows the smoothed trend together with its 95% confidence interval (a measure of uncertainty) represented by the shaded area on the chart, for UK and England.
Figure 3.2: Breeding woodland birds by species group in the UK and England, 1970 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 3.2:
- The indicators are based on the aggregated population trends of 37 species of woodland birds in the UK and 34 in England, of which 25 species are woodland specialists (22 in England) and 12 are generalists in the UK and England.
- Figure 3.2 shows the smoothed trend together with its 95% confidence interval for the different subgroups of birds. Trends for the UK and England are plotted side by side.
Table 3: Long and short-term trends at a glance for Woodland birds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1970 to 2023 | 37 / 34 | -35% | -10% | -38% | -12% |
Generalists | 1970 to 2023 | 12 / 12 | -7% | -10% | -14% | -15% |
Specialists | 1970 to 2023 | 25 / 22 | -47% | -10% | -49% | -11% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Woodland birds
The woodland bird index for both the UK and England includes individual measures for 37 species of woodland birds in the UK and 34 in England, of which 25 species are woodland specialists (22 in England) and 12 are generalists in the UK and England. The overall trend masks different underlying trends for specialist species, those which are highly dependent on woodland habitats, and generalist species, which are found in a wide range of habitats, including woodland. In the UK:
-
25% of generalists species have declined since 1970 and in the most recent 5-year period 58% of generalists species have declined
-
40% of specialist species have declined since 1970 and in the most recent 5-year period 48% of specialist species have declined
Similar trends are observed in England, with the exception that:
- in the long term more generalist species are showing little or no change in England (83%)
- in the long term more specialists are increasing in England (27%)
- in the most recent 5-year period more generalist species are declining (67%) and more specialists species declining (59%)
Figure 3.3: Long-term and short-term changes in species trends for woodland birds in the UK, 1970 to 2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 3.3:
- The indicators are based on the aggregated population trends of 37 species of woodland birds in the UK (25 species are woodland specialists and 12 species are woodland generalists).
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Woodland birds
Woodland generalists
The majority of generalist woodland species, many of which have adapted to using gardens and wooded areas in farmland landscapes, have not shown a substantial change over the long term, with three species showing notable decline in the UK, song thrush by 47% (51% in England), tawny owl by 49% and bullfinch by 50% (59% in England). Only one species showed a sustained high annual rate of increase in the UK, long-tailed tit by around 93% over the long term, and none in England.
In the short term, the number of species in decline has increased to 7 species (48 %), including four species showing strong declines: tawny owl by 20% (18% in England), bullfinch by 22% in the UK (33% in England), lesser whitethroat by around 14% in both the UK and England, and chaffinch by 21% (29% in England), the latter likely due to the disease trichomoniasis. No species have increased in this period.
Figure 3.4: Long-term and short-term changes in individual species trends for generalist woodland birds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 3.4:
- Figure 3.4 shows the individual population trends of 12 species of generalist woodland birds in the UK.
- Only those species for which the trend was significant and whose magnitude placed it outside of the ‘little or no change’ category are labelled with their percentage change.
- For visualisation purposes the axis have been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol. In figure 3.5, chiffchaff, nuthatch, great spotted woodpecker and blackcap all exceed 100%.
Woodland specialists
Four woodland specialists in the UK, lesser spotted woodpecker, spotted flycatcher, capercaillie and willow tit, have declined by over 90% relative to 1970 levels (lesser redpoll and wood warbler are also in strong decline in England). In contrast, over the same period, populations of chiffchaff have more than doubled, nuthatch have more than trebled and both blackcap and great spotted woodpecker have more than quadrupled in numbers, this shows how responses to pressures varies among species. In England strong increases were also observed in siskin and sparrowhawk populations.
In the short-term, 12 woodland specialists species (48%) were in significant decline. Of the four species mentioned above, all showed strong declines of between 32% and 48% in this 5-year period. Wood warbler experienced the strongest decline over the short term of 48% in the past five years. Nightingale and chiffchaff both show a strong increase of over 20% over the same period, although uncertainty around the nightingale’s trend means we cannot say this change is meaningful. Trends in long-distance migrants such as nightingales may reflect changing conditions on their wintering grounds in Africa. Whereas declines in residents such as willow tit and capercaillie will be due to pressures on their breeding grounds within the UK.
Figure 3.5: Long-term and short-term changes in individual species trends for specialist woodland birds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 3.5:
- Figure 3.5 shows the individual population trends of 25 species of specialist woodland birds in the UK.
- Only those species for which the trend was significant and whose magnitude placed it outside of the ‘little or no change’ category are labelled with their percentage change.
- For visualisation purposes the axis have been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol. In figure 3.5, chiffchaff, nuthatch, great spotted woodpecker and blackcap all exceed 100%.
- Some woodpecker species names have been shortened for this plot: LS is lesser spotted, GS is greater spotted and G is green.
Factors affecting woodland bird populations
Woodland covers 13% of the UK’s land area, providing trees and other vegetation suitable for nesting, foraging opportunities and cover from predators.
The declines in woodland birds have several known and potential causes, such as a lack of woodland management (including the reduction of traditional practices such as coppicing) and increased deer browsing pressure, both of which result in a reduced diversity of woodland structure and reduced availability of suitable nesting and foraging habitats. Changes in farmland management, such as the removal of hedgerows, adversely impacted many of the species in the indicator which have substantial populations outside of woodland, for example, in farmland and gardens. In addition, several declining woodland birds are long-distance migrants, and a decline in the extent or quality of habitats used outside of the UK in the non-breeding season (in stop-over sites or African wintering areas) may be a significant factor affecting these species. Positive factors include the increasing area of woodland cover and milder winters potentially having a beneficial impact for some species.
For more information about the evidence for this indicator, see the evidence statement Annex 1.04 Evidence Statement for C5b Woodland Birds.
4. Breeding water and wetland bird populations in the UK and England
Indicator trend description: Water and wetland
The water and wetland bird indices have declined by 10% in the UK and 4% in England since 1975. However, this is not a meaningful change due to the lower level of confidence in the indicator.
In the UK the water and wetland bird index has remained fairly stable for most of the period since data collection started in 1975 but declined between 2005 and 2010 and fluctuated at this level since then. In the 5 years since 2018, the indicator has shown little to no change.
In England, the index trends have followed a similar pattern but with the overall index being above the baseline until 2020, when it declined due mainly to trends observed in the wet grassland species. The overall index has been in general decline since the mid 2000s, and declined by 7% over the most recent 5-year period.
The overall indicators for both the UK and England mask large differences in the trends of the individual habitat subgroup indices found within this group of birds, reflected in the wider confidence intervals.
Water and wetlands include rivers, lakes, ponds, reedbeds, coastal marshes, other wet grasslands, and lowland raised bogs. Together these total 3% of the UK’s area and provide important habitats for birds. Species included in the wetland indicator are those defined as having a positive association with waterways or wetlands, but in practice, these overlap markedly with those classified as ‘lowland wetland’ species and also include some upland birds and those also associated with farmland, for example reed bunting and yellow wagtail.
Figure 4.1: Breeding water and wetland birds for 26 species in the UK and England, 1975 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 4.1:
- The indicators are based on the aggregated population trends of 26 species of wetland birds in the UK (of which 4 species are birds of fast flowing water, 4 are birds of reedbeds, 6 are birds of slow flowing and standing water, and 8 are birds of wet grasslands). There are an additional 4 species which don’t belong to any particular sub-habitat.
- The smoothed trend together with its 95% confidence interval (a measure of uncertainty) are represented by the lines and shaded area on the chart, for UK and England.
Key results for individual habitat subgroups indices:
- The index for birds of fast flowing water was 18% lower in 2023 than in 1975, although this change is not meaningful. Like the overall indicator for breeding wetland and waterways birds, it dipped during the early 2010s, although not as low as in the 1980s, and has shown little or no change in the short term.
- The index for birds of reedbeds increased by 21% since 1975 in the UK, but this is classified as little to no change due to wide confidence intervals. This indicator did increase by 25% over the long term in England. In the short term it increased by 15% in the UK and remained stable in England.
- Birds of slow flowing and standing water increased by more than 50% between 1975 and the late 2000s, possibly partly reflecting the benefit from wetland creation, but since then have been in continuous decline; in 2023 the index showed little or no change compared to the baseline. However, the index has shown a 14% decrease in the most recent 5-year period, reflecting the declines in this group in the last two decades.
- The index for birds of wetland meadow and wet grassland, was 49% lower in 2023 than in 1975. The majority of this decline, which has been driven mainly by drainage and the loss of key habitats, occurred between the peak in the mid-1980s and the mid-1990s. More recently the indicator has shown signs of stability, showing little or no change in the most recent 5-year period.
Figure 4.2: Breeding water and wetland birds by species group in the UK and England, 1975 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 4.2:
- The indicators are based on the aggregated population trends of 26 species of wetland birds in the UK and in England (of which 4 species are birds of fast flowing water, 4 are birds of reedbeds, 6 are birds of slow flowing and standing water, and 8 are birds of wet grasslands). There are an additional 4 species which don’t belong to any particular sub-habitat.
- Figure 4.2 shows the smoothed trend together with its 95% confidence interval for the different subgroups of birds, in the United Kingdom and England.
Table 4: Long and short-term trends at a glance for water and wetland birds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1975 to 2023 | 26 / 26 | -10% | 2% | -4% | -7% |
Fast flowing water | 1975 to 2023 | 4 / 4 | -18% | -2% | -21% | -10% |
Reedbeds | 1975 to 2023 | 4 / 4 | 21% | 15% | 25% | 11% |
Slow flowing and standing water | 1975 to 2023 | 6 / 6 | 8% | -14% | 10% | -18% |
Wetland meadow and wet grasslands | 1975 to 2023 | 8 / 8 | -49% | 7% | -30% | -6% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Water and wetland birds
Species included in the wetland indicator are those defined as having a positive association with waterways or wetlands, and also include some upland birds and those also associated with farmland, for example reed bunting and yellow wagtail. The 26 species of bird included in the water and wetland bird index are split into 4 categories of sub-habitat indicators. When interpreting these indicator trends, it should be noted that each sub-habitat trend is derived from relatively few species’ trends: 4 species are birds of fast flowing water, 4 are birds of reedbeds, 6 are birds of slow flowing and standing water, and 8 are birds of wet grasslands. There are an additional 4 species which don’t belong to any particular sub-habitat.
In the UK, 35% of wetland species have declined since 1975 and in the most recent 5-year period 42% of wetland species have declined.
In England, fewer species are in significant long term decline (27%), but more species are in significant decline over the most recent 5-year period (62%).
Figure 4.3: Long-term and short-term changes in species trends for water and wetland birds in the UK, 1975 to 2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 4.3:
- The indicators are based on the aggregated population trends of 26 species of wetland birds in the UK and in England (of which 4 species are birds of fast flowing water, 4 are birds of reedbeds, 6 are birds of slow flowing and standing water, and 8 are birds of wet grasslands).
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Water and wetand birds
Grey heron, kingfisher, oystercatcher and sand martin are included in the overall water and wetland bird indicator but not in any specific sub habitat indicator. These species show little or no change in the long term or short term with the exception of sand martin, which shows a strong increase in numbers in the UK over the short term (49%) and oystercatcher, which increased by 151% in England in the long term.
Birds of fast flowing water:
Although all the 4 species which make up this indicator are dependent on food from water, they share another characteristic of being found mainly in upland areas.
Over the long term in the UK indices for common sandpiper and grey wagtail have declined by 49% and 43% respectively, while numbers of goosander have more than doubled. In England only common sandpiper is in decline (45%).
In the short term the indices for common sandpiper, grey wagtail and dipper declined by between 8% to 13% in the UK (7% to 26% in England), while the index for goosander increased by 8%. However, wide confidence intervals around these species indexes mean we cannot say these are meaningful changes.
Birds of reedbeds:
In the long term, reed bunting and sedge warbler have shown declines in wetland habitats, of 68% and 53% respectively (60% and 56% in England). In contrast Cetti’s warbler has shown more than a 10-fold increase since 1988 (when the species exceeded the threshold for inclusion in the indicator, following the colonisation of the UK in 1972) and reed warblers have almost doubled in numbers since 1981 in the UK.
More recently, in the short-term, reed buntings have declined by 9% (14% in England), whilst sedge warbler and reed warbler numbers showed little change, and Cetti’s warbler increased strongly by 44% in both the UK and England.
Birds of slow flowing and standing water:
Over the long term, numbers of little grebe have decreased by 47% in the UK, although there is much uncertainty around this estimate. In contrast, numbers of mallards have more than doubled. In England, great crested grebe has declined by 39%.
In the short term, numbers of tufted duck, coot and both grebe species showed strong declines of between 16% and 20% in the UK and very similarly in England.
Birds of wetland meadow and wet grasslands:
Over the long term, the three species (little egret, teal and mute swan) have shown an increase in population size, little egret and teal more than doubling in number. In contrast, yellow wagtail (in wetland habitats) declined strongly, by 96% and three of the waders showed significant declines, snipe by 79% (67% in England), redshank by 68% (65% in England) and lapwing by 63% (in the UK). Wide confidence intervals in the snipe estimate means that we cannot say this is a meaningful change.
Over the short term, yellow wagtail and teal increased by 33% and 40%, respectively along waterways, although there is a great deal of uncertainty in these estimates. Numbers of lapwing fell strongly by 20% (35% in England). The indices for snipe and mute swan show little change but little egret showed strong increases of 17% (18% in England).
Figure 4.4: Long-term and short-term changes in individual species trends for water and wetland birds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 4.4:
- Figure 4.4 shows the individual population trends of 26 species of water and wetland birds in the UK
- Long term trends were calculated from as early as 1975, although for some species data collection started later. Exceptions are sand martin (1977), curlew (1979), lapwing (1979), goosander (1980), reed warbler (1980), Cetti’s warbler (1988), great crested grebe (1994), Teal (1994), Little Egret (2006 in the UK, 2004 in England).
- Habitat subgroups are denoted by the subscript numbers at the end of each species: F = Birds of fast flowing water; R = Birds of reedbeds; S = Birds of slow flowing and standing water; W = Birds of wetland meadow and wet grasslands.
- Only those species for which the trend was significant and whose magnitude placed it outside of the ‘little or no change’ category are labelled with their percentage change.
- For visualisation purposes the axis have been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol. In figure 4.4, goosander, mallard and Cetti’s warbler all exceed 100%.
Factors affecting wetland bird populations
The historical declines in breeding waders resulted from land management changes such as drainage, the intensification of grassland management and the conversion of coastal and floodplain grazing marshes to arable land. Where populations persist in small fragments of high-quality habitat, their nests and young can be vulnerable to predation, which is currently thought to be limiting the recovery of several species of breeding wader. However, a range of species, particularly those associated with standing water bodies, have benefited from habitat creation, especially from the restoration of post-extraction gravel pits. Additionally, there has been a net positive impact from improved survival rates due to the trend in climate towards milder winters.
5. Breeding seabird populations in the UK and England
Indicator trend description: Seabirds
The indicators for seabirds in the UK and England show different trends. Although seabird populations can vary by region and colony, the difference in the UK and England seabird indicators is strongly influenced by small differences in their species composition. In particular, the England index is strongly influenced by the inclusion of gannet, reliable trends of which are not available for the UK overall. The UK seabird indicator has declined by 25% since 1986. The population showed a steady decline between 2000 and 2013 but has since shown relatively little change in the 5 years since 2018. The England seabird index shows a different trend, having shown little or no change over both the long term as there is a high degree of uncertainty around their estimates. Data collection for seabirds was impacted by the COVID-19 pandemic and trends in some seabird species have been negatively impacted by the onset of Highly Pathogenic Avian Influenza (HPAI) since 2020. However, it is unlikely that the full effect of HPAI can be seen from the data currently available.
The UK coast consists of a wide variety of habitats such as sea cliffs, sand dunes, shingle ridges, machair and intertidal areas. Additionally, the area of sea around the UK amounts to three and a half times the land area of the UK (not including overseas territories). The marine habitats used for foraging by this group of birds include coastal lagoons and shallow coastal waters as well as deeper offshore waters throughout the UK. Although inland populations of seabird species are largely excluded, some species will also exploit terrestrial food sources.
Figure 5.1: Breeding seabirds for 13 species in the UK and 11 in England, 1986 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 5.1:
- The smoothed trend (solid line) together with the unsmoothed trend (dashed line) for the UK and England.
- There are no confidence intervals available for seabird indicators for the 2024 publication, pending consultation on a recent thorough review of the analytical methods used in the Seabird Monitoring Programme (SMP) species population indices, including confidence estimation. New analytical approaches will be developed and tested, and when available, the resulting trends will be incorporated into the aggregate seabird indicators. Trends should be interpreted with care due to the relatively small number of species included in some indices and the scarcity of data for some constituent species.
Key results for individual habitat subgroups indices:
- The index for surface feeders in the UK was 27% lower in 2023 than in 1986. There was an overall decline until 2013, when the index then stabilised and showed little or no change in the short term. In England, the picture was very similar for surface feeders over the long term, although they experienced a decline of 13% over the short term.
- The index for subsurface feeders in the UK showed little or no change since 1986. In the short term it also showed little change following a slight decline between 2003 and 2014. In England, the subsurface feeders are doing markedly better, with an overall increase of 169% since 1986 and little short term change since 2018. However, the England subsurface feeders index is strongly influenced by the inclusion of gannet, reliable trends of which are not available for the UK overall.
Figure 5.2: Breeding seabirds by species group in the UK and England, 1986 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 5.2:
- The indicators are based on the aggregated population trends of 13 species of seabirds in the UK and 11 species in England.
- The smoothed trend (solid line) together with the unsmoothed trend (dashed line) for the different subgroups of birds. Trends for the UK and England are plotted side by side.
- There are no confidence intervals available for seabird indicators for the 2024 publication, pending consultation on a recent thorough review of the analytical methods used in the Seabird Monitoring Programme (SMP) species population indices, including confidence estimation. New analytical approaches will be developed and tested, and when available, the resulting trends will be incorporated into the aggregate seabird indicators. Trends should be interpreted with care due to the relatively small number of species included in some indices and the scarcity of data for some constituent species.
Table 5: Long and short-term trends at a glance for Seabirds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1986 to 2023 | 13 / 11 | -25% | 2% | 5% | -5% |
Subsurface feeders | 1986 to 2023 | 3 / 4 | 4% | 9% | 169% | 2% |
Surface feeders | 1986 to 2023 | 5 / 5 | -27% | -4% | -29% | -13% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Seabirds
The seabird index for the UK includes individual measures for 13 species of seabirds (11 in England), of which 5 species are surface feeders and 3 species are subsurface feeders (4 in England). When interpreting these indicator trends, it should be noted that each sub-habitat trend is derived from relatively few species’ trends.
In the UK, 38% of seabird species have declined since 1986 and in the most recent 5-year period 31% of seabird species have declined. Subsurface feeder species are evenly distributed across the weak increase, weak decline and little or no change over the long term (33% in all categories), whereas all three species are increasing over the short term. In England, one subsurface feeder, gannet, not included in the UK indicator, is also increasing. 80% of surface feeding species are stable over the long term, with 20% showing a decrease. Whereas over the short term, 40% are increasing, 40% are decreasing and 20% are stable.
In England, more species are increasing both in the long term (18%) and over the most recent 5-year period (64%). Since 1986, more subsurface feeders are increasing in England (50%) and more surface feeders are declining (40%). Over the short term both groups have seen substantial increases, with 75% of subsurface feeders increasing and 60% of surface feeders increasing.
Figure 5.3: Long-term and short-term changes in species trends for seabirds in the UK, 1986 to 2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 5.3:
- The indicators are based on the aggregated population trends of 13 species of seabirds in the UK.
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Seabirds
The species-level breakdown of seabirds will be released once the Seabird Monitoring Programme publish their annual report.
Factors affecting seabird populations
The seabird index in the UK exhibits a different pattern to the England index. One reason for this difference is species composition. Some species breed only in Scotland whereas others are more widespread but have the bulk of their populations in northern parts of the British Isles, and there may be insufficient data to generate an England-only trend. It was also only possible to generate an England trend for gannet based on reliable data from a single large colony, but there are insufficient data representative of the UK population to produce a reliable UK trend for this species, meaning it is absent from the UK indicator. In addition, trends for some species may differ between the two areas.
Seabird populations are impacted by a range of pressures including climate change and fisheries induced changes in prey availability, introduced mammalian predators on islands, and disturbance.
Since 2020, the onset of HPAI in Britain’s seabirds has had devastating effects on many species. Particular impacts were seen among Arctic skua, many of the tern species and gannet (Tremlett, Morely and Wilson, 2024). According to UK seabird colony counts in 2023, declines of gannet were seen across Scotland and Wales, but with corresponding increases in England. As this indicator looks at short term species trends across the five year period 2017-2022, it is unlikely that the full impact of this disease outbreak is reflected in these indicators yet. Additionally, some of the most impacted species, such as Great Skua, are not included in this indicator, which only includes around half of the species of breeding seabirds in the UK (see the seabird colony count for a broader picture).
For more information about the evidence for this indicator, see the evidence statement Annex 1.06 Evidence Statement for C5d Seabirds.
6. Breeding upland bird populations in the UK and England
Indicator trend description: Upland birds
Upland bird populations have declined by 7% in the UK and 8% in England since 1994 although uncertainty in the England indicator means this is not a significant change. The UK and England indicators both show little to no change over the short term, although there is some variability amongst individual groups of species. Upland generalists have increased in both the UK and England over the short term, whereas upland specialists have declined over the past five years in England.
The upland areas in the UK are wild and isolated providing the ideal open habitat for a variety of bird groups. In England, these are comprised mainly of large areas in the north as well as pockets in the southwest, but are comparatively less widespread than in other UK countries. Largely open and often grazed with livestock, these areas provide the open habitats for waders and specialist moorland birds to breed or forage.
Due to its heavy reliance on the Breeding Bird Survey introduced in 1994, as well as relevant national single species surveys over this same period, this indicator covers the period 1994 to 2023. Therefore, this indicator does not cover the period where significant change was observed in some of the other habitat indicators, such as farmland and woodland.
Figure 6.1: Breeding upland birds for 32 species in the UK and 28 in England, 1994 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 6.1:
- The indicators are based on the aggregated population trends of 32 species of upland birds in the UK and 28 in England (of which 15 species are upland specialists (12 in England), 13 are generalists in the UK (12 in England), and 4 are upland riparian species in both the UK and England).
- Figure 6.1 shows the smoothed trend together with its 95% confidence interval (a measure of uncertainty) represented by the shaded area on the chart, for UK and England.
Key results for individual habitat subgroups indices:
- The index for upland specialists in the UK was 16% lower in 2023 than in 1994. It has decreased steadily over this period and then stabilised in the most recent five years, showing little or no change. For England, the most recent five years show a steep decline of 13% and these specialist species have declined much further overall, by 30% since 1994.
- The index for upland generalists in the UK has shown little change long term, but in the short term it increased by 11%. England generalist species follow a similar trend, but with a more dramatic increase of 26% since 1994 and 14% since 2018.
- Riparian upland species show a similar long-term trend across the UK and England, where they decreased by 10% since 1994 (18% in England), although uncertainty in this indicator means we are unable to say this is a meaningful change. Over the most recent five years, populations of riparian species in the UK have shown little or no change.
Figure 6.2: Breeding upland birds by species group in the UK and England, 1994 to 2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 6.2:
- The indicators are based on the aggregated population trends of 32 species of upland birds in the UK and 28 in England (of which 15 species are upland specialists (12 in England), 13 are generalists in the UK (12 in England), and 4 are riparian species in both the UK and England.
- Figure 6.2 shows the smoothed trend together with its 95% confidence interval for the different subgroups of birds. Trends for the UK and England are plotted side by side.
Table 6: Long and short-term trends at a glance for upland birds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1994 to 2023 | 32 / 28 | -7% | 3% | -8% | -2% |
Generalists | 1994 to 2023 | 13 / 12 | 6% | 11% | 26% | 14% |
Riparian | 1994 to 2023 | 4 / 4 | -10% | -2% | -18% | -10% |
Specialists | 1994 to 2023 | 15 / 12 | -16% | -2% | -30% | -13% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Upland birds
The upland bird indices for the UK and England includes individual measures for 32 species of upland birds in the UK and 28 species in England. These are disaggregated into 3 subgroups: specialists, generalists and riparian species. The upland specialist indices are comprised of the population trends for 15 species in the UK (12 species in England) characteristic of and found solely in upland, typically open moorland habitats. Upland generalists (13 species in the UK and 12 species in England) are widespread and often common in uplands but also found in other habitats such as lowland farms or woodland. For these species, most known to occupy several different habitats, the population trends used are derived solely from surveys in upland habitat. Upland riparian species (4 species in the UK and 4 England) are comprised of the population trends for species strongly associated with upland rivers and streams. The overall trend masks different underlying trends between these different groups.
In the UK:
- 38% of generalists species have declined since 1994, but with 46% increasing in the most recent 5-year period.
- 33% of specialist species have declined since 1994 and in the most recent 5-year period 22% of specialist species are in decline. No specialist species are showing increasing trends.
- 25% of riparian species have declined since 1994 and in the most recent 5-year period this has increased to 75% of riparian species in decline.
In England, the trends follow a similar pattern with the following deviations:
- fewer generalist species are in long and short term decline (17% and 33% respectively).
- more specialist species are in short term decline (56%), although some are increasing over the same period (11%)
- no riparian species are increasing over the short term and more species are decreasing over the long term (50%).
Figure 6.3: Long-term and short-term changes in species trends for upland birds in the UK, 1994 to 2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 6.3:
- The indicators are based on the aggregated population trends of 32 species of upland birds in the UK (15 species are upland specialists, 13 species are upland generalists and 4 species are upland riparian species).
- Over the long term, 32 upland species were assessed but only 26 could be assessed over the short term
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Upland birds
Upland generalists
Since 1994, numbers of red kite and stonechat increased in the UK by more than 100%. In England, numbers of stonechat reached almost a 700% increase. In contrast, numbers of both peregrine and redshank declined strongly by 80% and 57% respectively (78% and 56% in England). Hooded crow experienced moderate declines of 34% in the UK, as did lapwing and pied/white wagtail (43% and 31% for the UK). In England, both of these species showed little change and hooded crow only appears in the UK indicator. England also saw long term increases in wren of 62%.
Numbers of red kite and stonechat increased strongly in the short term by 29% and 80% in the UK respectively (23% and 108% in England). In England, numbers of oystercatchers have increased strongly by 21%. Cuckoo, skylark and oystercatcher increased moderately in the short-term for the UK, between 10% and 15%. Numbers of peregrine and pied/white wagtail have declined strongly in the short term for the UK, by 39% and 15% respectively and for England, carrion crow joins these strong declines (13%).
Upland specialists
Since 1994, numbers of whinchat have declined strongly by 60% (65% in England). Four other species (dotterel, curlew, ring ouzel and wheatear) exhibited moderate declines of between 30% and 46%, although there is uncertainty around the ring ouzel estimate. In England there are no trends for dotterel, but wheatear show similar moderate declines, and Twite show strong declines of 66%.
Over the short term, whinchat declined in England, by 38%, and red grouse declined strongly in the UK, by 31%. Short-term trends are not available for 6 of the specialist upland species, monitored through periodic surveys.
Upland Riparian
Since 1994, 3 of the 4 upland riparian species in the UK showed little overall change but common sandpiper showed a moderate decline of 41% (37% in England). Dipper also saw declines of 29% in England, but there is a relatively large amount of uncertainty around this estimate.
Over the short term, uncertainty around all of these species’ trends means that we cannot say their changes are meaningful. Grey wagtail, dipper and common sandpiper have all declined by between 8% and 13% in the UK. Goosander has increased by 8% over the same period, although no such trend was detected for England. Dipper and common sandpiper saw strong declines in England over this period, of 26% and 20% respectively.
Figure 6.4: Long-term and short-term changes in individual species trends for upland birds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 6.4:
- Figure 6.4 shows the individual population trends of 32 species of upland birds in the UK.
- Habitat subgroups are denoted by the subscript numbers at the end of each species: G = upland generalist species; R = species of riparian habitats; S = upland specialist species.
- Only those species for which the trend was significant and whose magnitude placed it outside of the ‘little or no change’ category are labelled with their percentage change.
- For visualisation purposes the axis have been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol. In figure 6.5, stonechat and red kite both exceed 100% increase in the long term.
Factors affecting upland bird populations
Upland birds are vulnerable to a number of pressures contributing to the pattern of overall decline, particularly among the upland specialists. UK uplands have a long history of intensive sheep grazing, game management and commercial afforestation. Reviews of causes of change have identified changes in grazing pressure, forest expansion, especially by non-native conifers, site-based predator control and climate change effects such as droughts, as some of the major pressures for open-nesting moorland species whereas upland passerines are affected by reductions in vegetation structure and composition. Raptors have benefited from reduced persecution although this still remains a threat. The overall stability in generalist species may reflect a balance between long term negative impacts of land use changes and benefits of climate change as more adaptable species are able to colonise new areas and increase in abundance.
7. Wintering waterbird populations in the UK and England
Indicator trend description: Wintering waterbirds
Wintering waterbird populations have increased by 90% in the UK and 78% in England since 1975/1976. However, since the early 2000s the index has been in decline, with a drop of 8% in both England and the UK over the most recent five year period. Over the short term this decline is mostly driven by wildfowl rather than wader species. This indicator relates to numbers of these species during the winter period from September to the following March each year.
The term waterbird is used to describe all birds that inhabit or depend on water and wetland habitats; this chapter is about waterbirds that over-winter in the UK, some of which also breed here. The wintering waterbird trends in this chapter are not included in the all breeding birds index, but that index does include breeding population trends for species in the wintering waterbird indicator which also breed in the UK and for which breeding trends are available. Wintering populations typically originate from breeding populations outside the UK, which represent completely different populations or races.
Figure 7.1: Wintering waterbirds for 46 species in the UK and 40 in England, 1975/1976 to 2022/2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 7.1:
- The indicators are based on the aggregated population trends of 46 species of wintering waterbirds birds in the UK and 40 in England, of which 15 (14 in England) species are waders in the UK and in England and 31 species are wildfowl in the UK (26 in England).
- Figure 7.1 shows the smoothed trend (solid line) together with the unsmoothed trend (dashed line) for UK and England.
- Data from wintering waterbirds monitoring schemes are based largely on full counts at colonies or at wetland and coastal sites of markedly varying size. This means that bootstrapping methods cannot be applied reliably and hence trends for these groups are currently presented without confidence intervals.
- As there are no 95% confidence intervals for wintering waterbirds, we instead provide the unsmoothed index as a view of the underlying variability of the data.
- Each year of data corresponds to a wintering period from September of that year to the following March.
Key results for individual habitat subgroups indices:
- The index for waders in the UK was 77% higher in 2022/2023 than in 1975/1976. The index has been relatively stable since the late 90s, with no change in the most recent five years. For England, the waders show a very similar trend of 82% increases since 1975/1976 and little change over the last five years.
- The index for wildfowl in the UK was 101% higher in 2022/2023 than in 1975/1976. The index has been in decline since the early 2000s, with a decrease of 12% in the most recent five years. For England, the wildfowl show a very similar trend of a 79% increase since 1975/1976 and no change over the last five years.
Figure 7.2: Wintering waterbirds birds by species group in the UK and England, 1975/1976 to 2022/2023
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 7.2:
- The indicators are based on the aggregated population trends of 46 species of wintering waterbirds birds in the UK and 34 in England, of which 15 species are waders in the UK and in England and 31 species are wildfowl in the UK (26 in England).
- Figure 7.2 shows the smoothed trend (solid line) together with the unsmoothed trend (dashed line) for the different subgroups of birds. Trends for the UK and England are plotted side by side.
- Data from wintering waterbirds monitoring schemes are based largely on full counts at colonies or at wetland and coastal sites of markedly varying size. This means that bootstrapping methods cannot be applied reliably and hence trends for these groups are currently presented without confidence intervals.
- As there are no 95% confidence intervals for wintering waterbirds, we instead provide the unsmoothed index as a view of the underlying variability of the data.
- Each year of data corresponds to a wintering period from September of that year to the following March.
Table 7: Long and short-term trends at a glance for wintering waterbirds birds in the UK and England
Index | Time period | Species number (UK / England) | Long-term change UK | Short-term change UK | Long-term change England | Short-term change England |
---|---|---|---|---|---|---|
All | 1975/1976 to 2022/2023 | 46 / 40 | 90% | -8% | 78% | -8% |
Waders | 1975/1976 to 2022/2023 | 15 / 14 | 77% | 0% | 82% | 1% |
Wildfowl | 1975/1976 to 2022/2023 | 31 / 26 | 101% | -12% | 79% | -12% |
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Species trends: Wintering waterbirds
The wintering waterbirds index for both the UK and England includes individual measures for 46 species of wintering waterbirds in the UK and 40 in England, of which 15 species are waders in the UK (14 in England) and 31 species are wildfowl in the UK (26 in England). The overall trend masks different underlying trends for wader species and wildfowl species.
In the UK:
- No wader species have declined in winter numbers since 1975/1976, and 40% have increased.
- In contrast, for the most recent 5 year period, fewer winter populations are increasing with 27% of wader populations declining.
- 10% of wildfowl wintering populations have declined since 1975/1976 and in the most recent 5 year period 58% of wildfowl populations have declined.
In England the trends are very similar, though more wintering wildfowl populations declined over the long term (19%) and fewer over the short term (50%).
Figure 7.3: Long-term and short-term changes in species trends for wintering waterbirds birds in the UK, 1975/1976 to 2021/2022
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figures 7.3:
- The indicators are based on the aggregated population trends of 46 species or races of wintering waterbirds birds in the UK and 40 in England, of which 15 species are waders in the UK (14 in England) and 31 species are wildfowl in the UK (26 in England).
- Each row represents 100% of the species within a habitat/sub-habitat.
- Each bar within a row shows the percentage of species within the indicator that are categorised as showing an increase (strong or weak increase), a decrease (strong or weak decline) or little or no change.
Species breakdown: Wintering waterbirds
The wintering waterbird indicator breaks down some species (barnacle goose, brent goose, greylag goose and white-fronted goose) into distinct races and/or flyway populations. These populations breed and winter in different areas within and outside the UK, and hence are treated separately here, as in most conservation assessments and initiatives.
The UK and England versions of the wintering waterbird indicator also have a different species composition. For waders, ringed plover only appears in the UK data. Likewise for wildfowl, Icelandic greylag goose, Greenland white-fronted goose, light-bellied brent goose (of Nearctic origin), and both populations of barnacle goose (Greenland and Svalbard) only appear for the UK indicator.
Waders
Since the winter of 1975/1976 in the UK, the indices for avocet and black-tailed godwit showed the strongest increases, wintering numbers have now increased substantially (and avocet is only included in the indicator since 1989/1990). Golden and grey plover also show strong increases long term, more than doubling in this time period. Lapwing and sandering also show increases long term of 61% and 98% respectively.
In the short term, the indices for the bar-tailed godwit, lapwing and golden plover declined strongly by 18%, 16% and 17% respectively. The only 3 wader species to increase in recent years are: dunlin by 6%, black-tailed godwit by 9% and sanderling by 10%.
These figures for England look very similar both long and short term, although in the short term purple sandpiper also increased by 12%. Unlike in the UK, dunlin shows little change short term in England.
Figure 7.4: Long-term and short-term changes in individual species trends for wading species of winter waterbirds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 7.4:
- Figure 7.4 shows the individual population trends of 15 species of wader species in the UK.
- Only those species for which the trend was significant are labelled with their percentage change.
- For visualisation purposes the axis has been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol.
Wildfowl
Since the winter of 1975/1976, decreases were observed for the Bewick’s swan, European white-fronted goose and pochard in the UK, which declined by 91%, 71% and 64%, respectively. 13 of the wildfowl species are showing strong increases long term, including light-bellied brent goose (of Nearctic origin), Mute Swan and Teal. The British/Irish greylag goose, and gadwall are estimated to be increasing substantially in wintering numbers. Wintering numbers of whooper swan and Svalbard light-bellied Brent goose are also estimated to have increased greatly.
In the short term, notable decreases were observed for the Bewick’s swan, scaup and Icelandic greylag goose which showed declines of 81%, 40% and 23% respectively. Five other species are in strong decline (European white-fronted goose, pochard, wigeon, dark-bellied brent goose, and Svalbard barnacle goose) of between 14% and 22%. A further 10 species are in weak decline of between 6% and 13%, including coot, pink-footed goose, great crested grebe and several species of duck. Light-bellied brent goose (of Nearctic origin) and British/Irish greylag goose are increasing strongly (21% and 16%, respectively), with a further five increasing species (pintail, cormorant, shoveler, whooper swan and Svalbard light-bellied brent goose) of between 7% and 13%.
For England, eider and scaup also join the long term declines, by 64% and 86%. There are fewer species in strong increase, only 10 overall with the strongest increases seen in British/Irish greylag goose and whooper swan. Over the short term there are fewer species weakly and strongly declining. Of the 6 species in strong decline, the England list also includes red-breasted merganser and these species are in declines of between 15% and 76%.
Figure 7.5: Long-term and short-term changes in individual species trends for wildfowl species of wintering waterbirds in the UK
Source: British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and the Joint Nature Conservation Committee (JNCC).
Notes for Figure 7.5:
- Figure 7.5 shows the individual population trends of 31 species of wildfowl species in the UK.
- Some species names have been shortened for this plot: LB is light-bellied, DB is dark-bellied. Regions have been included in brackets to describe the origin of any sub-populations of species.
- Only those species for which the trend was significant are labelled with their percentage change.
- For visualisation purposes the axis has been truncated to between -100% and +100%. For species that exceed these limits, the exact percentage change is labelled next to the bars and marked with a † symbol.
Factors affecting wintering waterbird populations
Populations of wintering wetland birds are affected by a range of factors including conditions in the high latitude countries where they breed, with breeding productivity increasing for species including black-tailed godwit but decreasing for others such as Greenland white-fronted geese. There is good evidence of a strong climate change impact on the indicator in recent years, with milder winters leading to the wintering ranges of many species, including mallard, pintail, goldeneye, pochard, bewick’s swan, ringed plover, curlew and bar-tailed godwit, increasingly shifting away from the UK. In addition, local changes, such as wetland creation and changes in agricultural management, have had an impact on waterbird populations within the UK.
Like seabirds, wintering waterbirds have been impacted by the Highly Pathogenic Avian Influenza (HPAI) outbreak. In winter 2021/22, around one third of Svalbard barnacle geese died in the Solway Firth in Scotland. The following winter, thousands of Greenland barnacle geese died on Islay in Scotland, and there have been reports of significant mortality in pink-footed and greylag geese and in mute swan. It remains to be seen whether HPAI has longer term impacts on wintering populations of ducks, swans or geese. The long term impacts are on wintering populations of ducks, swans or geese currently unknown.
For more information about the evidence for this indicator, see the evidence statement Annex 1.04 Evidence Statement for C5e Wintering Waterbirds.
Main notes: methodological detail, limitations of the indicators and further information
The bird population indices have been compiled in conjunction with the British Trust for Ornithology (BTO), the Joint Nature Conservation Committee (JNCC), and the Royal Society for the Protection of Birds (RSPB) from a wide range of sources, principally:
- the Common Birds Census (from 1966 to 2000)
- the BTO/JNCC/RSPB Breeding Bird Survey (from 1994 to 2023)
- the BTO/ Waterways Bird Survey(from 1974 to 2007)
- the BTO/JNCC/RSPB Waterways Breeding Bird Survey with support from the Environment Agency (from 1998 to 2023)
- the BTO/RSPB/JNCC Wetland Bird Survey counts (from 1975/1976 to 2022/2023)
- the WWT Goose & Swan Monitoring Programme in partnership with the JNCC and Scottish Natural Heritage
- the Seabird Monitoring Programme (from 1986)
- the Periodic Seabird censuses supplied by JNCC, RSPB, the Seabird Group, SOTEAG (Shetland Oil Terminal Environmental Advisory Group) and other partners
- Monitoring of scarce and rare breeding birds by the Statutory Conservation Agency and RSPB Annual Breeding Bird Scheme (SCARABBS) and the Rare Breeding Birds Panel (from 1970 to 2023)
The census sources provide an indication of the average annual rate of change between censuses for some species, and this is assumed to apply to each year between censuses
More information about individual species trends, including photographs and background to the changes in population are available via the BTO website. Some regional analysis is also published as part of the Breeding Bird Survey, including for other constituent countries of the UK. More information about the State of UK birds can be accessed through the RSPB website. Details on the monitoring of scarce and rare breeding birds, including annual reports, can be found on the website of the Rare Breeding Birds Panel.
More information on how a smoothed trend was produced when a year of data is missing is in the BTO Research Report ‘Production of smoothed population trends when a year of data is missing’ on BTO’s ‘Bird Indicators’ web page.
For more information on the Upland Indicator, see BTO Research Report ‘Upland Indicator Report’ on BTO’s ‘Bird Indicators’ web page.
The indices cover birds that are native to the UK, excluding rare (less than 500 breeding pairs, or 300 in England) and introduced species. The indices portray the annual changes in abundance. Within the indices, each species is given equal weighting, and the overall index is the geometric mean of the individual species indices. Individual species populations within the index may be increasing or decreasing, irrespective of the overall index trends. Species indices are derived by modelling count data and estimates are revised when new data or improved methodologies are developed and applied retrospectively to earlier years.
The indices are considered to give reliable medium to long-term trends, but strong reliance should not be attached to short term changes from year to year.
The individual species included within each indicator are given in the relevant data sets published alongside this update for a list of birds in each group.
Smoothing is a standard procedure in the generation and reporting of bird population trends. The smoothing methodology involves the application of a thin plate smoothing spline to remove the short-term peaks and troughs due to weather effects and any between year sampling error. Research by the BTO and RSPB further developed this procedure to enable the production of an indicator based on smoothed individual species’ indices.
Bootstrapping, a standard statistical technique, is used to calculate 95% confidence intervals in the indicators and in change over any specified period. The width of the confidence interval for a given indicator is influenced by the number of species in that indicator and the precision of the individual species trends that make up that indicator. The precision of trends varies between species; this is true even for species for which trends come from the same source, due to the variation in sample size. Therefore, the size of confidence intervals varies among habitat indicators.
For the farmland bird index, it should be noted that although 20 species were originally chosen for the index, a reliable annual index is not available for barn owl, so that species is excluded.
For more information, please see the Technical Background document associated with this release