Online solutions and the "Wallacean shortfall" : what does GBIF contribute to our knowledge of species' ranges?

Aim To investigate the contribution to range filling, range extent and climatic niche space of species of information contained in the largest databank of digitized biodiversity data: the global biodiversity information facility (GBIF). We compared such information with a compilation of independent distributional data from natural history collections and other sources. Location Europe. Methods We used data for the hawkmoths (Lepidoptera, family Sphingidae) to assess three aspects of range information: (1) observed range filling in 100 km × 100 km grid cell squares, (2) observed European range extent and (3) observed climatic niche. Range extents were calculated as products of latitudinal and longitudinal extents. Areas derived from minimum convex polygons drawn onto a 2-dimensional niche space representing the two main axes of a principal component analysis (PCA) were used to calculate climatic niche space. Additionally, record-based permutation tests for niche differences were carried out. Results We found that GBIF provided many more distribution records than independent compilation efforts, but contributed less information on range filling, range extent and climatic niches of species. Main conclusions Although GBIF contributed relevant additional information, it is not yet an effective alternative to manual compilation and databasing of distributional records from collections and literature sources, at least in lesser-known taxa such as invertebrates. We discuss possible reasons for our findings, which may help shape GBIF strategies for providing more informative data.