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Verification of records is vital to ensure data quality. Only records validated and verified by County Recorders enter Butterfly Conservations UK Recording Schemes. Butterfly Conservation recommends the use of iRecord inbuilt verification tools, find out more below and here. In this section we also highlight other tools that can be used. These are compatible with use of iRecord, for example you can use them to check records displayed publicly before import.

Bespoke tools have been developed to help County Recorders and Verification Assistants to verify moth and butterfly records. These tools help automate the process and highlight records that require further scrutiny. The choice of tool to use is a personal, some County Recorders will prefer to work with the Spreadsheet Validators, whereas others will prefer the NBN Record Cleaner. We suggest trying both options to see what suits you best.

Photo record verification in iRecord

The Butterfly Conservation iRecord linked websites such as BNM Online, NMRS Online and the iRecord Butterflies app allow for photographs to be uploaded as part of the record.

Provided that the photograph is good quality and shows the distinguishing features of the species, it is relatively straightforward to accept or reject a photograph record. Records with photographs can be accepted as Correct in iRecord, if you can confirm that the species has been identified correctly on the basis of the photos.

In some cases you will need to redetermine the record because the supplied photograph indicates the recorded species was misidentified. In this case you can redetermine the record to another species.

Guidance on how review records with photographs in iRecord can be found here.

Tip for verifiers

The redetermine button is shown as indicated below by the red circle.

Verification in iRecord (without photograph or specimen)

If the record is not accompanied by a photograph Butterfly Conservation recommends the verification decision is based on the following questions:

  1. Is the record within the known flight-period of the species?
  2. Is the record within the known distribution of the species?
  3. What is the level species identification difficulty?
  4. Is the habitat correct?
  5. Does the determiner (normally the recorder although this could be a third party if the recorder has sought ID advice) have sufficient experience to identify this species?
  6. Has the determiner had previous records of this species (or similar species) accepted?
  7. Has the determiner attended relevant training?
  8. Has the verifier seen the determiner’s ID abilities in action?
  9. Do you need any further information to verify the record? If so, contact the recorder.
  10. Apply verification decision

Using rule-based verification assistance tools in iRecord

iRecord has inbuilt rules that check the flight period, distribution and species identification difficulty for butterflies and moths, which Butterfly Conservation recommends as an additional reference check during verification. The system will highlight records that break the inbuilt rules with specific icons:

As County Recorder, you can also create your own local rule set based on known distributions and flight periods. Butterfly Conservation have worked with UKCEH to develop this functionality based on feedback from County Recorders as part of the Supporting Science project. If you find the inbuilt iRecord tools are not quite right for your local situation, we recommend you try out some local iRecord rules. Find out how to do this here (coming soon).

If a record passes the automated rule-based assistance checks (inbuilt or local) and is given a ‘green thumbs-up’ this is an aid to help you identify records that should be marked as Considered Correct. This is an additional check for records for which you are not able to personally confirm the species identification using photos or a voucher specimen. Records flagged with the ‘green thumbs-up’ have a higher degree of confidence that the record is likely to be correct, based on a number of criteria including the identification difficulty, date, location and recorder skills/experience etc. However, please do give these 'green-thumbs up' records a spot-check as on occasion a recorder will provide a photograph that is clearly not the species they have recorded.  

Record validation spreadsheets

The Moth and Butterfly Spreadsheet Validators have been developed by Mark Cubitt, County Moth Recorder in East Scotland. The butterfly version has been developed for launch with this toolkit. You can use these to help validate and verify records in spreadsheets. Any potentially erroneous records are colour coded depending upon their severity. The Spreadsheet Validators also perform data reformatting, allowing for onward import into iRecord, MapMate or a more general output.

Use this tool for checking data formats and assisting with the validation and verification of the content in an Excel, csv or tab-delimited spreadsheet of butterfly or moth records.

The Validator produces a new worksheet that can be imported into iRecord or MapMate or a less-specific General format depending on the format option selected.

Warnings about errors are colour coded depending on whether they are medium or high severity. In these cases, some manual remediation, such as editing incorrect grid refs and correcting species name spellings is required prior to import. Using a variety of selected checkboxes, the Validator can also perform a range of Verification analyses.


NBN Record Cleaner

NBN Record Cleaner is a free software tool to help improve the quality of biological records. NBN Record cleaner performs similar checks on the records to the Spreadsheet Validators. Any records that fail the validation and verification rules are output for your further scrutiny.

The tool helps you to identify errors in the data and works on a number of formats including CSV, tab delimited, excel spreadsheets, Recorder and MapMate.

Firstly, the data are validated, this process spots bad dates, bad grid references and incorrect species names. Once the validation issues are remedied the data are reloaded and verified against a set of inbuilt rules. These rules relate to flight period and distribution, species records that are outside of the known flight period and or distribution are flagged for further investigation.

The tool is developed for any taxa. There are various options and tips that Butterfly Conservation staff have developed for the checking of butterfly and moth records using the tool. Please review our guidance (coming soon) and get in touch if you need support.

Reference checklist of Lepidoptera names

The Checklist of the Lepidoptera of the British Isles contains the current scientific names & codes of butterflies and moths that are resident and transitory resident species along with species that are believed to be extinct and immigrants. It also includes adventive species- species that have been imported and found in the wild. The book is available to buy from booksellers and there is also a downloadable Excel spreadsheet which is regularly updated.

In iRecord linked surveys, the species names are auto-filled with Checklist standard names. Spreadsheets can be more problematic for species name spelling mistakes so additional caution is required. Supplying a spreadsheet template to your local recorders can help minimise this issue, see resources. You can also use the Butterfly or Moth Validation spreadsheet to check incoming data sheets’ species names against the Checklist names.

Micro-moth verification specialists

Across the UK there is a network of Verification Specialists who deal with micro-moth verification. These volunteers are available to help you with your micro-moth verification. The network operates at a regional and national level. If a regional verification specialist is unable to confirm the identification of a species it can be escalated to the national experts.

Contact your regional (or national) specialist for advice and assistance with verifying micro-moth records. A list of these experts can be found in Assemble.


The tools detailed above can help County Recorders perform the vital process of verification. Many tools are available within iRecord itself to aid verification of records within the system. The Moth and Butterfly Spreadsheet Validators colour code any issues in the data making them easily detectable. The validators can also re-format the data into the County Recorders preferred output for import into iRecord, MapMate or a general format. The NBN Record cleaner produces an output that details records that fail the distribution and flight period rules that need further scrutiny. Choosing which tool to use is a personal choice. Don’t forget that you also have peer support available as well as tools. Please take advantage of County Recorder meetings, the communication channels within the volunteer database, and the network of Micro-moth Verification Specialists.



Butterfly Conservation iRecord verification training (coming soon)

iRecord’s library of guidance for verifiers (webpages and downloads available when logged in with a verifier account)

iRecord’s guide on how to review records with photographs with the new photo record page (pdf)

iRecord’s guide on how to set up templates for record comments (pdf)

iRecord’s guide on the new sample bulk verification option (pdf) (video)

iRecord’s guide to grid column settings (video)

iRecord’s guide to verification keyboard shortcut keys (video)

iRecord’s guide to verifying iNaturalist records (pdf)

Butterfly Conservation and iRecord’s presentation on communicating with iNaturalist recorders (pdf)

iRecord’s guide to understanding and verifying BirdTrack records (pdf)

iRecord’s guide on filtering records based on co-ordinate uncertainty (pdf)

Biological Recording Company: What is iRecord? (video)

Biological Recording Company’s tour of iRecord verification portal (video)

Butterfly Conservation’s filtering butterfly records in iRecord demo (video)

Biological Recording Company’s Querying records in iRecord demo (video)

Biological Recording Company’s single record verification in iRecord demo (video)

Biological Recording Company’s bulk verification in iRecord demo (video)

Butterfly Conservation’s bulk verification of butterfly records in iRecord demo (video)

Offline tools and support

British and Irish moths: an illustrated guide to selected difficult species (covering the use of genitalia characters and other features) (pdf)

Guide to using NBN Record Cleaner software (coming soon)

Moth Validation Spreadsheet (Link)

Butterfly Validation Spreadsheet (Link)

Checklist of the Lepidoptera of the British Isles Excel download (link)

Data entry spreadsheet template for recorders (Excel)