Managing observations when taxonomy changes: the case of Artportalen and Dyntaxa

What this was about

Johan Liljeblad explained how Sweden's 26-year-old citizen observatory Artportalen stays aligned with the national taxonomic database (Dyntaxa, started 2004), which uses stable taxon-concept identifiers rather than names. Taxonomy is published continuously and harvested nightly, but Artportalen applies changes every two months with news notes: name changes need no action, lumps move observations to the new taxon ID, and splits keep observations on a 'collective taxon' unless information (e.g. geography or phenology) allows assignment to one segregate. Edge cases include chained lumps, excluded taxa and fully revised concepts, so the process remains semi-manual with expert review, which is manageable at about 100 new taxa and 10-15 reassignments per cycle.

Why it matters. A working national model for keeping millions of observations consistent with an evolving taxonomy, relevant to any portal linked to a changing backbone.

In the room

• Every taxon has an ID and at least one recommended name; the ID stays stable to the concept while names change, and changes are traceable.
• Taxonomy is harvested nightly (Darwin Core file) but applied to Artportalen every second month to manage changes and inform users.
• Not every taxon in the database is reportable; a filter controls what can be reported.
• Lumps move observations to the replacing ID; splits keep observations on a collective taxon unless extra information allows reassignment.
• Complications include multi-step lumps, taxa later excluded from Sweden, and totally revised concepts with no single target.
• Around a million records are added per two months; about 100 new taxa and 10-15 reassignments per cycle are checked by organism-group experts.
• Sweden has about 60,000 species in the database and observations of about 40,000.

Notable moments