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State of Nature Report Scotland 2019 State of Nature Report Scotland 2019 3

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State of Nature Report Scotland 2019 State of Nature Report Scotland 2019 3 2019 SCOTLAND 2 State of Nature Report Scotland 2019 State of Nature Report Scotland 2019 3 Though some Gannet THE HEADLINES pressures on nature, In this report we have drawn on the best available data on Scotland’s biodiversity, notably freshwater pollution, • Legislation has driven marked produced by partnerships between conservation non-governmental organisations (NGOs), have reduced in recent decades, reductions in emissions of some the pressures that have caused harmful pollutants, although research institutes, UK and national governments, and thousands of dedicated volunteers. the net loss of biodiversity negative impacts remain. We have focused on the trends in species as the key evidence of how nature is faring. continue collectively to have a • The need for more homes in negative effect. response to changing human The collection of systematic data on species’ trends often does not • Agricultural productivity, linked population demographics means fully cover timescales relevant to ecological changes. Widescale to the intensification of land that thousands of hectares (ha) data collection only began 20–50 years ago. The results should management and the decline of habitat including farmland, be interpreted in that context and viewed against a backdrop in farmland nature, is still woodland and wetland are of profound historic human influences on nature in Scotland. increasing, although some built on every year, although Photo: Andrew Parkinson Scotland makes a very significant contribution to UK biodiversity; farmers have adopted wildlife- woodland cover has increased it has a high proportion of the UK’s upland habitats, including its friendly farming techniques. and new wetland habitat has most mountainous terrain, and has species found nowhere else been created. The impacts of fishing in the UK. Some of Scotland’s species, such as the White-script • Average temperatures in and climate change Lichen and Scottish Primrose, are found nowhere else in the Scotland have increased by on species’ abundance and world. Historic deforestation, intensified livestock grazing since nearly 1°C, with widespread distribution are evident throughout the 18th century, widespread sporting management since the impacts on nature Scottish seas. At the base of the food 19th century and large-scale commercial forestry during the evident already. web, plankton communities have 20th century have all had significant effects on upland wildlife. Photo: Drew Buckley changed in response to warming seas. While fish stocks are showing signs of recovery, the impacts of unsustainable fishing persist. The ramifications of other pressures on Red squirrel Our data show that the abundance the marine environment, such as noise and plastic pollution, are of and distribution of Scotland’s concern but remain less clear. species has on average declined over recent decades and most measures indicate this decline Photo: Oliver Smart has continued in the most recent This report decade. There has been no let-up showcases just a in the net loss of nature in Scotland. few of the exciting Photo: Kevin Sawford conservation initiatives, Photo: Peter Cairns involving thousands of people, Scotland has a long 24% 14% 49% 62% 11% 38% intended to help nature decline in decline in of species have of species show of species are decline in the flourish across Scotland, history of love for, and average species’ average species’ decreased in strong changes. threatened. Scottish breeding delivered through partnerships abundance. distribution. abundance. Our wildlife is Of the 6,413 species seabird indicator fascination with, our between 1986 of individuals, landowners, Our indicator of Our indicator of Of the species undergoing found in Scotland and 2016. NGOs and government. natural heritage. average species’ average species’ showing either rapid change, that have been abundance of 352 distribution, strong or moderate the proportion of assessed using However, the Thanks to this, thousands of terrestrial and covering 2,970 changes in species defined Regional Red List abundance volunteers collect data on our wildlife freshwater species terrestrial and numbers, 49% as showing criteria, 11% have indicators for fish every year. Without their dedication has fallen by 24% freshwater species have decreased strong changes been classified as species, both pelagic this report would not be possible; since 1994. There over a broad range and 28% have in abundance, threatened with and demersal, we thank them all. has been very little of taxonomic increased. Likewise either increasing extinction from show some signs change in the rate groups, has fallen more species or decreasing, rose Great Britain. of recovery from of decline in the last by 14% since 1970, have decreased in from 45% since deep historic lows 10 years. and is 2% lower distribution (33%) 1994 to 62% over in the Celtic and than in 2005. than increased the last 10 years. North Seas. (20%) since 1970. #STATEOFNATURE 4 Key findings Drivers of change Historical change UK key findings State of Nature Report Scotland 2019 5 KEY FINDINGS Our species’ status metrics make We focus on measuring change over TRENDS IN ABUNDANCE FOR BIRDS, MOTHS, BUTTERFLIES AND MAMMALS use of two broad types of data: two periods: from 1994 through to 2016 Sota rou auae ator broadly stable since, with a statistically for abundance data and from 1970 to Abundance data from a number 200 non-significant decline in average We are able to present trends 2015 for occupancy data. Our short- of well-established monitoring 180 abundance of 4% (CI -9% to 0%). term period covers the final 10 years in status for more species than schemes in Scotland and the UK 160 The indicator was 7% lower in 2016 of these time series, telling us how 140 ever before in State of Nature encompassing 352 species (birds, compared to 2006. Scotland’s nature is doing now. 120 2019. This is due to new datasets mammals, butterflies and moths). (1975 100) 100 • The abundance indicator for Many of these species are popular becoming available and the 80 25 butterfly species starts in 1979 e e development of analytical tools to record, and are relatively easy to 60 and shows a slight but statistically identify and to observe, making it 40 which enable a much broader non-significant increase in average possible to count individuals to get a 20 abundance of 9% (CI -27% to +45%). range of taxonomic groups to 0 measure of relative abundance. Our 1975 1980 1990 2000 2010 2016 The indicator was 19% lower in 2016 be represented. Birds (143) Moths (175) Butterflies (25) Mammals (9) abundance metrics report the average compared to 2006. change in relative abundance across Unsmoothed indicator Using multispecies indicators, • The abundance indicator for nine these species. our goal is to communicate a Based on smoothed trends: 25% (CI -49% to -1%). Over the short mammal species starts in 1998 and term, the indicator was 10% lower in clear, objective assessment Occupancy data from large-scale • The abundance indicator for overall shows a statistically significant biological records datasets from 175 moth species starts in 1975 2016 compared to 2006. decline in average abundance of 9% of the state of biodiversity which we can now calculate trends for and shows a statistically significant • The abundance indicator for 143 bird (CI -14% to -4%). The indicator was in Scotland. The metrics we 2,970 species across a wider range of decline in average abundance of species starts in 1994 and has been 5% lower in 2016 compared to 2006. present show how measures taxonomic groups (including mammals, of average species’ status have vascular plants, lichens, bryophytes changed over time as well as and a number of invertebrate groups). CHANGE IN SPECIES’ DISTRIBUTION IN SCOTLAND showing the variation in trends These trends measure the change in Sota oua ator (2,970 species) o ter Sort ter the proportion of occupied sites in 1970–2015 2005–2015 • Over the long term, 33% of species between species. (2,970) (2,970) Scotland, so our metrics effectively 120 100% showed strong or moderate declines and 20% showed strong or moderate report the average change in 100 For full methods see State of Golden Eagle 80% distribution for these species. increases; 47% showed little change. Nature 2019 at www.nbn.org.uk/ Photo: Laurie Campbell 80 • Over the short term, 37% of species stateofnature2019. 60% (1970 100) 60 showed strong or moderate declines 40% and 30% showed strong or moderate e e SCOTLAND-SPECIFIC COMBINED ABUNDANCE INDICATOR BASED ON TRENDS OF MOTHS (175 SPECIES), 40 of species Percentage increases; 33% showed little change. BIRDS (143 SPECIES), BUTTERFLIES (25 SPECIES) AND MAMMALS (9 SPECIES) 20% 20 • Over the long term, 23% of species Sota auae ator (352 species) o ter Sort ter individual species’ trends. To examine 1994–2016 2006–2016 0 0% showed a strong change in distribution All (352) All (344) this, we have allocated species 1970 1980 1990 2000 2010 2015 Strong increase Moderate increase (either increase or decrease). Over the 140 100% Indicator 90% credible intervals into trend categories based on the Little change Moderate decrease short term this rose to 45% of species. 120 magnitude of population change, over Strong decrease 80% Using a different, binary categorisation: the long- and the short-term periods. 100 The occupancy indicator for 2,970 declines could reflect more severe 60% • Over the long term, 62% of species 80 • Over the long term, 49% of species terrestrial and freshwater species underlying abundance declines. (1994 100) showed negative trends and 38% showed strong or moderate declines shows a decline in average distribution To examine the variation in species’ 60 40% showed positive trends in distribution; e e and 28% showed strong or moderate of 14% between 1970 and 2015, and distribution trends, we allocated trends 40 of species Percentage over the short term, 57% of species increases; 24% showed little change.
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