The benefits of biodiversity data sharing: how well do national and - - PowerPoint PPT Presentation

The benefits of biodiversity data sharing: how well do national and local biological records overlap?

Dr Daniel Chapman (CEH) & Steve Hannah (TWIC)

Daniel Chapman Steve Hannah

Background

• Two major sources of UK biological records
• National Biodiversity Network (NBN)
• Partnership of data collectors and users
• National coverage
• Local Records Centres (LRCs)
• Regional coverage
• Incomplete coverage in Scotland
• Locally tailored data support

Background

• SBIF Action 7: “Encourage Local Records Centres (LRCs)

to carry out a gap analysis on their data holdings and to identify if data available through the NBN Gateway can fill the gaps”

• Can NBN and LRCs enhance each others’ data?
• What is the potential benefit of data sharing to users?

Overview of our initial study

• Focal LRC: The Wildlife

Information Centre for the Lothians and Borders (TWIC)

• Focal taxa: 66 Habitats

Directive taxa occurring in region

• Annexes 2, 4 & 5
• Comparison of:
• Data sources
• Temporal overlap
• Spatial overlap

Records used in the study

• 14370 from TWIC
• 6638 from NBN
• 224 datasets with records inside TWIC region
• Applied for access to all providers
• Accessed 55 datasets with Habitats Directive species

NBN sources for the TWIC region

6% 76% 81% 82% 94%

0% 25% 50% 75% 100% No access 100 m or better 1 km or better 2 km or better 10 km or better

% of datasets accessed

NBN and LRC have different data sources NBN TWIC

Why the different data sources?

• Lots of TWIC-only data sources are individual recorders
• Don’t always know if these find their way onto NBN via other

datasets

• Some NBN-only sources may only contribute at edge of

region

• e.g. Fife LRC and Natural England
• Some providers give different subsets of their data(sets) to

TWIC and NBN

• May have different names
• E.g. BSBI

Temporal overlap of records

NBN has relatively more historical records

Spatial overlap of records

• Record density maps for each species
• 100 m, 1 km, 2 km, 5 km & 10 km
• Measures of overlap between NBN andTWIC
• Spearman’s correlation on record density
• True Skill Statistic on record presence/absence
• Both range from -1 (no overlap) to 1 (perfect overlap)

Example of high overlap

ρ = 0.813 TSS = 0.781

Example of low overlap

ρ = 0.212 TSS = 0.265

Overlap across the taxa

• Overlap is generally quite high but variable
• Similar overlap across resolutions (except 100 m)

The potential benefit of greater sharing

NBN would gain 38% more 10 km grid squares TWIC would gain 18% more 10 km grid squares

NBN TWIC

Conclusions

• The LRC and NBN have very different data sources
• NBN has more historical records than the LRC
• LRC has more individual recorder data

Conclusions

• Spatial overlap was variable but quite good
• However, more data sharing would provide a major

improvement to data quality from both sources

• Should benefit all users
• Need to understand why data is not shared

Caveats

• We couldn’t access all the NBN data
• 94% of datasets at 10 km resolution
• Only one LRC
• May not be representative
• Highly non-random selection of species
• What about common species or invasives?

Thank you for listening!

Acknowledgements: All data providers, Christine Johnston, Ed Mackey, SBIF steering group and members.