Data from: Developing a database of Australian grasshopper occurrences from historic field survey notebooks spanning 54 years (Orthoptera: Acrididae, Morabidae, Pyrgomorphidae, Tetrigidae)

The baseline distribution data for all species of a given group in a
region can provide fundamental insights into biogeographic questions about
historic patterns of species richness, population trends, and extinction.
Grasshoppers are one major group of insects for which a continent-wide
perspective on their geographic distribution can be obtained. This is
because they were extensively surveyed in Australia for 54 years
(1936-1989) as part of Commonwealth expeditions to obtain specimens for
the Australian National Insect Collection (ANIC). Field notebooks recorded
from those surveys, under the direction of ANIC curator and director K. H.
L. Key, form the principal source of historic distribution records for
grasshoppers in Australia. We digitized all 223 notebooks (2486 pages) and
transcribed all the field trips conducted in Western Australia (WA) and
Tasmania (47 notebooks, 590 pages). We then carefully geocoded all
sampling sites of the transcribed notebooks, following the odometer
readings and descriptions of routes from a suitable reference point using
historic topographic maps and Google Earth. In total, we extracted 8975
geographic coordinates for 477 species having a confirmed or putative
taxonomic name of (only 170 of these species have been formally
described). We found that species richness varied spatially, with highest
richness in arid interior and north of WA. Historic grasshopper surveys
were non-randomly distributed across both WA and Tasmania with the highest
survey intensity around coastal regions. Variation was observed among
surveyors in terms of the number of species detected per site,
between-site distance, and the season of survey being conducted. Overall,
however, the dataset is among the most comprehensive continent-wide
surveys of Australian invertebrates and will greatly facilitate future
work on their ecology, biogeography, conservation, and responses to
environmental change.