Application of Museum Data for Insect Conservation

Abstract

Across the globe, insect conservation is often impeded by a lack of species-specific data on population size and geographical range, leading to difficulties in assessment of conservation and threat status. However, utilising specimens and records held within natural history museums may help to overcome such limitations, as these can provide geographical and morphological information on species. This study used specimens and their associated data, from the New Zealand Arthropod Collection (NZAC), to obtain key information from threatened species and their non-threatened congeners. A range of insect groups were covered, with primary focus on Curculionidae (Coleoptera), Mecodema (Coleoptera: Carabidae), Calliphoridae and Therevidae (Diptera), Hemiptera, Colletidae (Hymenoptera), and Geometridae (Lepidoptera). Specimen data included locality, date, habitat, and morphological measurements, from over 21,000 specimens from 539 species. The New Zealand Department of Conservation classifies 33 of these species as Threatened and 132 as At Risk. Locality data for insect specimens were cross-referenced using the New Zealand Landcover Database and this demonstrated that the Protected Area Network provided significantly less coverage for insect species currently classified as Threatened or At Risk, than it did for non-threatened species. Results also revealed that variables such as body size, geographical distribution, and environmental variables were not valid as predictors of the current threat classification system, when Threatened species and At Risk species were compared to Not Threatened congeners. There was a strong bias for At Risk species to be found on offshore islands. In summary, the current threat classification system does not accurately reflect the conservation needs of insect species. This has significant implications for the future of New Zealand insect conservation, and the Protected Area Network.