Sampling forest canopy arthropod biodiversity with three novel minimal-cost trap designs

Sampling arthropods in the upper canopy of tall trees presents a range of challenges associated with portability, cost, placement, replication and collection. Detailed schematics and instructions are presented here for three trap designs: sticky CD cases, plastic bottle hanging flight-intercept traps and drink bottleneck funnel crawl traps. By using simple and salvageable materials such as plastic drink bottles and compact disc cases, the financial cost of an arthropod sampling regime in the crowns of old-growth Tasmanian stringybark trees Eucalyptus obliqua (L’Herit) was kept to a minimum. The traps collected comparatively diverse communities: the sticky traps catching high levels of Diptera, Hymenoptera and Coleoptera; the funnel traps catching Diptera, Hemiptera and Coleoptera; and the hanging traps catching Diptera, Coleoptera and Lepidoptera. The sticky traps were ranked best, and the funnels worst, when integrating relative merits of cost, transport, durability, construction, placement, retrieval, sorting and arthropod condition.