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Topic: Unexpected handling of records where grid ref straddles VCs

Records where the grid ref straddles one or more VC boundaries seem to be assigned only to the VC having the larger area. (Please confirm) and other fields within the section 'Additional political boundaries information' may be being computed inconsistently.

Although the field title 'Watsonian Vice Counties (GB)' implies that all VCs are shown, in practice I only ever find one. Would it be possible to assign boundary-straddlers to all VCs so that they are included when searching by any such VC?

Example: record https://records.nbnatlas.org/occurrence … 4280737dd3 has Occurrence ID iBRC17560955.Ad and of a dragonfly recorded in grid square SO2111 which is mostly in Breconshire but straddles the VC boundary into Monmouthshire.
I do not have a side-by-side comparison between Preserved (modern) and Historic (VC) Counties of Wales but the assignments to this record may not be consistent:

- Districts, Boroughs and Unitary Authorities (Great Britain): Sir Fynwy - Monmouthshire
- Watsonian Vice Counties (GB): Breconshire

David Hepper
Records Officer, British Dragonfly Society

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Re: Unexpected handling of records where grid ref straddles VCs

Hello David,

Apologies for the delay in getting back to you. Thank you for taking the time to share this feedback with us.

At the moment the NBN Atlas assigns an occurrence record to a vice county using the occurrence's central latitude and longitude. This is because the OSGB grids on the NBN Atlas are part of a spatial layer, and the atlas does not currently have the functionality to process intersections between spatial layers (i.e., the atlas cannot currently identify intersections between the OSGB grid layer and vice county layer).

However, we will log your very helpful feedback as this functionality may become available in the future.

Thank you again for taking the time to share your feedback with us, this is most appreciated.

Kind regards,
Rhiann

Rhiannydd Stock
NBN Atlas Support Officer