D7: Species supporting ecosystem functions
Short Description
All species have a functional role within ecosystems such as photosynthesis, respiration, decomposition, nutrient cycling, predator-prey and symbiotic relationships such as pollination. Plants, fungi, algae, invertebrates and soil micro-organisms are particularly important. The presence, abundance and diversity of species are key factors in determining the resilience of ecosystems to environmental changes, including climate change and disease, and the maintenance of ecosystem services. Further research is required to develop this indicator, building on the existing UK pollinator indicator and defining species groups and functions for inclusion.
Readiness and links to data
An interim indicator is presented here that shows trends in the distribution of pollinators (bees and hoverflies) in the UK. While these metrics are official statistics and finalised, additional research and development is required to include a range of species groups important for supporting ecosystem functions in England. This distribution index, also referred to as an occupancy index, measures the number of 1 kilometre grid squares in which species are recorded each year. It will increase when a species becomes more widespread and decrease when a species becomes less widespread. These data are published annually as UK Biodiversity Indicator D1c – Status of pollinating insects.
Indicator components
Figure D7i: Change in the distribution of pollinators in the UK, 1980 to 2022
Table D7i: Change in the distribution of pollinators in the UK, 1980 to 2022
| Year | Unsmoothed index | 90% credible interval lower bound | 90% credible interval upper bound |
|---|---|---|---|
| 1980 | 100.00 | 100.00 | 100.00 |
| 1981 | 101.87 | 100.77 | 102.94 |
| 1982 | 103.63 | 102.24 | 105.04 |
| 1983 | 105.33 | 103.83 | 106.86 |
| 1984 | 107.00 | 105.50 | 108.48 |
| 1985 | 108.54 | 107.08 | 110.04 |
| 1986 | 109.59 | 108.12 | 111.09 |
| 1987 | 110.17 | 108.67 | 111.81 |
| 1988 | 109.12 | 107.63 | 110.69 |
| 1989 | 107.42 | 105.92 | 108.94 |
| 1990 | 105.60 | 104.16 | 107.09 |
| 1991 | 104.15 | 102.58 | 105.69 |
| 1992 | 103.49 | 101.93 | 105.06 |
| 1993 | 103.47 | 102.00 | 104.94 |
| 1994 | 103.67 | 102.21 | 105.16 |
| 1995 | 103.13 | 101.56 | 104.76 |
| 1996 | 101.89 | 100.38 | 103.40 |
| 1997 | 100.14 | 98.73 | 101.61 |
| 1998 | 98.58 | 97.19 | 100.02 |
| 1999 | 97.54 | 96.15 | 98.95 |
| 2000 | 96.81 | 95.41 | 98.21 |
| 2001 | 96.45 | 95.05 | 97.85 |
| 2002 | 96.68 | 95.26 | 98.04 |
| 2003 | 96.91 | 95.60 | 98.28 |
| 2004 | 96.62 | 95.27 | 97.97 |
| 2005 | 96.25 | 94.89 | 97.61 |
| 2006 | 95.62 | 94.29 | 97.00 |
| 2007 | 94.38 | 93.12 | 95.68 |
| 2008 | 92.70 | 91.44 | 94.04 |
| 2009 | 90.67 | 89.44 | 91.96 |
| 2010 | 88.08 | 86.89 | 89.34 |
| 2011 | 85.44 | 84.21 | 86.65 |
| 2012 | 83.19 | 82.01 | 84.34 |
| 2013 | 81.34 | 80.25 | 82.48 |
| 2014 | 79.73 | 78.63 | 80.85 |
| 2015 | 78.39 | 77.27 | 79.48 |
| 2016 | 77.43 | 76.34 | 78.55 |
| 2017 | 76.49 | 75.41 | 77.54 |
| 2018 | 75.64 | 74.55 | 76.73 |
| 2019 | 75.14 | 74.02 | 76.31 |
| 2020 | 75.14 | 73.97 | 76.29 |
| 2021 | 75.57 | 74.33 | 76.87 |
| 2022 | 76.12 | 74.51 | 77.83 |
Trend description for D7i
There has been an overall decline in the UK pollinators index since its peak in 1987, and in 2022, the index had decreased by almost 31% compared to this peak and by almost 24% compared to its value in 1980. More recently, however, the trend has levelled off and shows little or no change in the distribution of pollinators in the UK since 2017.
Assessment of change
The indicator ‘Status of pollinating insects’ is also reported in the UK Biodiversity Indicators, which presents short and long-term assessments for the same time periods used in this Outcome Indicator Framework assessment. These assessment results are reused here as they are more tailored to the specific dataset and factor-in information on confidence. The methodology from the UK Biodiversity Indicators is also used here to assess change over the medium term. The assessments show little or no change in the distribution of pollinators in the UK in the short term and a decline (deterioration) over the medium and long term.
Change since 2018 has also been assessed using the UK Biodiversity Indicators methodology. There has been little or no change in the index for relative abundance of priority species in the UK since 2018. However, this result is based on only 5 data points so should be considered as indicative and not evidence of a clear trend.
Details on the UK Biodiversity Indicators assessment methodology for this indicator can be found in the Technical Annex of the UK Biodiversity Indicator page. Further information on the standard assessment used in the Outcome Indicator Framework, along with details on the methodology, is provided in the Assessment background page. Summaries by 25 Year Environment Plan goal and information on indicator links are presented in the Assessment results pages.
Table D7i: Assessment of change
| Component | Subcomponent | Period | Date range | Percentage change | Smoothing function | Assessment of change |
|---|---|---|---|---|---|---|
| D7i | Unsmoothed index | Short term | 2017 to 2022 | -0.48 | Unsmoothed data | Little or no change |
| D7i | Unsmoothed index | Medium term | 2012 to 2022 | -8.50 | Unsmoothed data | Deterioration |
| D7i | Unsmoothed index | Long term | 1980 to 2022 | -23.88 | Unsmoothed data | Deterioration |
Note that unsmoothed data presented in the indicator charts were used for percentage change calculations. Percentage change refers to the difference seen between the first and last years in the specified date range.
Figure D7ii: Long-term and short-term changes in the distribution of individual pollinator species in the UK, 1980 to 2022
Table D7ii: Long-term and short-term changes in the distribution of individual pollinator species in the UK, 1980 to 2022
| Time period | Strong decline | Weak decline | Little or no change | Weak increase | Strong increase |
|---|---|---|---|---|---|
| Long term (1980–2022) | 21.32 | 20.56 | 39.09 | 10.66 | 8.38 |
| Short term (2017–2022) | 24.37 | 12.44 | 24.37 | 15.99 | 22.84 |
Trend description for D7ii
The long-term decline in the overall distribution of pollinators in the UK shown in D7i masks the trends of the individual species within the index, 42% of which have become less widespread, 39% of which have shown little or no change and 19% of which have become more widespread since the index began in 1980. Over the short term (between 2017 and 2022) results for the individual species trends are more balanced, with 37% of species becoming less widespread, 24% showing little or no change and 39% becoming more widespread in the latest 5 years for which data are currently available.
Assessment of change
No assessment of change was undertaken for this indicator as it is based on the same underlying data that are already assessed in D7i.