| year | No | Year or year range. Single year: "2024". Range: "2020,2024". Filters by observation year. Both endpoints inclusive. Omit the field to search every year — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |
| limit | No | Number of records to return (default 20, max 300). | |
| month | No | Calendar month (1–12). Useful for seasonal distribution queries. | |
| offset | No | Pagination offset. GBIF serves offset+limit up to 100,001 and rejects anything past it, with no cursor or scroll to continue from. To reach a result set larger than that, split it into per-datasetKey searches using a DATASET_KEY facet from gbif_occurrence_facets — gap-free and high-cardinality, unlike YEAR, which leaves undated records in no bucket — rather than paging deeper. | |
| country | No | ISO 3166-1 alpha-2 code, uppercase, of where the occurrence was recorded (e.g., "GB", "US", "DE", "SE"). Not the publisher's country — that is publishingCountry, and the two disagree on most records. Lowercase and alpha-3 forms ("gb", "USA") match nothing upstream, which is why only the uppercase two-letter form is accepted here. Take a value from a COUNTRY facet on gbif_occurrence_facets; an uppercase pair GBIF does not know ("XX") is rejected upstream by name. | |
| geometry | No | WKT polygon for geographic filtering (e.g., POLYGON((8 47, 9 47, 9 48, 8 48, 8 47))). Coordinates are longitude latitude. Takes precedence over decimalLatitude/decimalLongitude. Omit the field to search everywhere — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |
| taxonKey | No | GBIF backbone taxon key from gbif_match_species. Preferred over scientificName — matches all synonyms automatically. Matches the given taxon and all descendant taxa (subspecies, varieties, etc.). | |
| datasetKey | No | Restrict results to a single dataset by its GBIF dataset UUID (8-4-4-4-12 hex). Obtain one from gbif_search_datasets, gbif_get_dataset, a DATASET_KEY facet (gbif_occurrence_facets), or the datasetKey field on an occurrence record. Omit the field to search every dataset — an empty string is rejected rather than read as no filter, because GBIF answers a blank datasetKey with the unfiltered result set. | |
| isInCluster | No | Filter to records flagged as likely duplicates (true) or exclude them (false). Omit to include all. Note: GBIF does not expose a cluster identifier — only the membership flag. To de-duplicate, set isInCluster: false to exclude all clustered records. | |
| basisOfRecord | No | Filter by how the occurrence was recorded. HUMAN_OBSERVATION covers citizen science. PRESERVED_SPECIMEN covers natural history collections. | |
| hasCoordinate | No | When true, return only georeferenced records (those with coordinates). When false, return ONLY records without coordinates. Omit the parameter entirely to include all records regardless of coordinate presence. | |
| stateProvince | No | State, province, or first-level administrative division, matched as a verbatim string — exact and case-sensitive. GBIF stores what each dataset recorded without normalizing it, so there is no vocabulary to guess from: "England", "England - Greater London", and "Greater London" are three distinct values, and "england" is none of them. Take one from a STATE_PROVINCE facet on gbif_occurrence_facets scoped the same way and pass it back unchanged — an unmatched value returns zero records rather than an error. Omit the field to search every state or province — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. Records carrying no stateProvince match no value, so this cannot partition a scope. | |
| scientificName | No | Scientific name filter. Less precise than taxonKey — does not match synonyms. Use taxonKey from gbif_match_species for reliable results. Supplying both does not narrow the search: GBIF combines the two taxon filters with OR, so the result is the union of the two, not their intersection. Omit the field to search every name — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |
| decimalLatitude | No | Latitude range as "min,max" (e.g., "47.0,48.5"). Decimal degrees, WGS84. Combine with decimalLongitude for a bounding box. Omit the field to leave latitude unbounded — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |
| decimalLongitude | No | Longitude range as "min,max" (e.g., "8.0,9.5"). Decimal degrees, WGS84. Combine with decimalLatitude for a bounding box. Omit the field to leave longitude unbounded — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |
| occurrenceStatus | No | Presence/absence filter. Defaults to PRESENT: an ABSENT record documents a survey that looked for the taxon and did not find it, so including one would read as a sighting of the opposite. Use ANY for both (GBIF's own default), or ABSENT for non-observations alone. | PRESENT |
| publishingCountry | No | ISO 3166-1 alpha-2 code, uppercase, of the organization that published the record — not where the occurrence was observed, which is country. The two differ constantly: of 60,290,950 records observed in GB, 1,548,928 were published by US organizations. Take a value from a PUBLISHING_COUNTRY facet on gbif_occurrence_facets. Lowercase and alpha-3 forms ("us", "USA") match nothing upstream, which is why only the uppercase two-letter form is accepted here. | |
| iucnRedListCategory | No | Restrict to records whose taxon carries this IUCN Red List category: CR Critically Endangered, EN Endangered, VU Vulnerable, NT Near Threatened, LC Least Concern, DD Data Deficient, EX Extinct, EW Extinct in the Wild, CD Conservation Dependent. Records with no category are excluded when this is set. | |
| coordinateUncertaintyInMeters | No | Filter by coordinate uncertainty radius in meters. Range format: "min,max" (e.g., "0,1000" for sub-kilometer precision). Both endpoints inclusive. Omit the field to accept any uncertainty — a blank or whitespace-only value is rejected rather than dropped, because GBIF answers one with the unfiltered result set. | |