On the dates of GBIF mobilised primary biodiversity records

Abstract

There are more than 390 million primary biodiversity data records published by hundreds of data publishers through the GBIF network. Thus, the GBIF network is the single most comprehensive index for this kind of data. Ensuring or, at least assessing data quality is of capital importance for the reliability and usability of this data. While conducting a time data gap analysis on this mass of data, we have detected some issues with the way date information is processed and shared. Dates can be obscured or altered under certain circumstances, when a specific combination of publisher’s error or date handling features, and faulty or inadequate date parsing and processing routines gets chained together. The extent of the date unreliability (either at the source or through GBIF portal) is relatively low, and problems are concentrated in a few data publishers. The types of errors and misprocessing in dates through the sources and the published records are analysed, impact on the overall data quality of the published index was assessed, and corrective measures are suggested.