Fruit Fly (Tephritidae, Diptera) Communities along Elevational and Disturbance Gradients in Papua New Guinea Rainforests
Papua New Guinea’s first ever multi-purpose National Forest Inventory project included in its biodiversity observation three target invertebrate groups: fruit flies (Insecta: Diptera: Tephritidae), moths (Insecta: Lepidoptera: Geometridae) and ants (Insecta: Hymenoptera: Formicidae). In PNG, these groups are well known taxonomically, are easy to identify and are species-rich. Distributed across different forest types and altitude, they respond to environmental conditions and therefore are of high bio-indicative value representing a mix of ecological roles and trophic levels in forest communities. Assessment of indicator targets of the forest components of floral and faunal communities and the soil condition gives status of the health of the forests (Hughes et al., 1992). Papua New Guinea National Forest Inventory offers a presentable platform for floral assessment in which the faunalistic component can be cost-effectively incorporated, (Novotny and Toko, 2015). PNG has the greatest national diversity of tropical fruit fly species (Diptera: Tephritidae: Dacinae) in the world (Leblanc et al., 2001). Diverse as it is with over 250 species, it is also economically important as it includes numerous pest species. Fruit fly pest species prevalence has provoked agricultural research on fruit flies in PNG with collaborations from Australia in recent years which is ongoing. Fruit flies including the agricultural pest species, also attack numerous rainforest fruits and are therefore an important component of forest communities (Novotny and Toko, 2015). The Tephritidae was chosen as one of the indicator targets for assessment of forest health because fruit flies have good indicator features of large population sizes, short life-spans, fast reproduction with multiple overlapping generations, and they respond rapidly to environmental change (Hilty and Merenlender, 2000). The objective of my study therefore is to assess the response of fruit fly species diversity, distribution and community composition to different forest types and at various elevations in the region surveyed. The record will be used for long term resurvey purpose to ascertain changes that may occur.
Steps to reproduce
The samples for the study were collected from 37 sites from the provinces of Madang, Morobe, Eastern Highlands, West New Britain and Western Highlands Province respectively from which the PNG NFI were conducted commencing in 2016 to current 2018 (Fig. 3.1). The selection of forest survey sites (called here clusters) was done by placing random coordinates to satellite maps using Collect Earth which is one of the Open Foris software. The resulting sites cover a wide range of the forest types, geographic areas, land-use and climates. For each survey, a cluster contains 10 Steiner traps, each baited with a combination of three lures: Cue lure, Methyl eugenol (ME) lure and Zingerone. They were infused with insecticide and placed in predetermined locations within the periphery of the clusters.