Biodiversity managers need robust and cost-effective tools to monitor ecosystem health and outcomes of management actions. Large arboreal invertebrates are important components of forest ecosystem food webs, but can be difficult and expensive to monitor because of their inaccessibility. Frass drop has been used extensively in Europe and North America to index the abundance of arboreal invertebrates, but has rarely been used in an ecological context in New Zealand.
Although reproductive and behavioural studies have been conducted on captive tree weta, there have been very few ecological field studies of any of the weta species involving free-ranging, marked individuals. The mountain stone weta (Hemideina maori) is a tree weta that lives on rock tors in the alpine region of the South Island of New Zealand. Over three seasons each of 480 adults and 789 juveniles was individually marked on four large and 14 small tors to gather baseline information on aspects of H. maori’s life cycle and life history.