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Nick Isaac, Tom August & Gary Powney

Trends in British Biodiversity since 1970

@drnickisaac

Biodiversity in Crisis

Target 12By 2020 the extinction of known threatened species has been prevented and their conservation status, particularly of those most in decline, has been improved and sustained.

• Population time-series• Annual estimates of status• Taxonomically restricted

How do we know if the targets have been met?

• Red List indices• Many species• Temporally-imprecise

Botham et al (2011) UK Butterfly Monitoring Scheme Annual Report 2011.

Biological records: the third way

• Volunteer citizen scientists have been recording biodiversity for centuries

• A rich source of data for measuring change

• But the data are biased in space and time

Atlases: Stock & change in distribution

Biodiversity change using atlases

Thomas, JA et al. (2004). Comparative losses of British butterflies, birds, and plants and the global extinction crisis. Science, 303 1879–81

Estimating trends from biological records

http://figshare.com/articles/Extracting_trends_from_citizen_science_data_BES_version_/778699

MethodData Trends

Trends in British Biodiversity since 1970

• What proportion of species are declining?

• What are the net changes in biodiversity?

• Which taxa are doing best/worst?

• Are common or rare species faring best?

Vertebrates

Plants

Other Invertebrates

Insects

0 500 1000 1500 2000 2500

Number of species

Quantitative trends for >5000 species

No bird or mammals!

Status of British Biodiversity since 1970

• More species show significant increases (19%) than declines(14%)

Significance = Power

• More significant trends are apparent in groups with most data

Dragonflies & Damselflies

Moths

Long-hornbeetles

Soldier Beetles

Hoverflies

Vascular Plants

Trends in British Biodiversity 1990-2000

• Good news: Median change +2.4%; Net change +4%• Bad news: >1000 species would qualify as VU or worse

Median

Comparative patterns among taxa

Below the line: Rare species are doing better than common (& vice versa)

Median % change

Net

% c

hang

e

Conclusions

• Mixed news about the UK biodiversity• More increases than declines• Many species in steep decline

• Big losses among some groups, especially ladybirds & centipedes

• Substantial biotic homogenisation

• We can report against CBD targets for a much greater range of taxa than previously possible

https://github.com/BiologicalRecordsCentrehttp://bit.ly/18wTrrK

AcknowledgmentsColin Harrower, David Roy, Helen Roy, Michael Pocock, Chris PrestonMark Hill, Arco van Strien

@drnickisaac