Terrestrial invertebrate surveys and rapid biodiversity assessment in New Zealand: lessons from Australia

Although invertebrates play a key role in the environment, their conservation and use in environmental monitoring is often considered “too difficult” and consequently ignored. One of the main problems in dealing with invertebrates is that even limited sampling can yield large numbers of specimens and an enormous diversity of species. Other problems include the taxonomic impediment (i.e. high proportions of invertebrate taxa are undescribed and there are few specialists available to identify specimens), the lack of knowledge on species distribution, diversity and ecological roles, and the fact that invertebrates are undervalued by the general public. A number of rapid biodiversity assessment (RBA) approaches have been suggested to overcome these problems. RBA approaches generally fall into four categories: (1) restricted sampling in place of intensive sampling (sampling surrogacy); (2) the use of higher taxonomic levels than species (species surrogacy); (3) the use of recognisable taxonomic units (RTUs) identified by non-specialists (taxonomic surrogacy); and (4) the use of surrogate taxa in place of all taxa (taxon-focusing). Australia has a long history of using invertebrates in terrestrial ecological studies, and in developing and using RBA approaches. Therefore, New Zealand could benefit from the experienced gained in Australia. Potentially one of the most useful RBA approaches to take in New Zealand involves focusing resources and attention on a limited range of taxa. However, this requires substantial communication, discussion, and agreement over which taxa should be selected for conservation priorities and environmental monitoring in terrestrial ecosystems.