Using a pheromone lure survey to establish the native and potential distribution of an invasive Lepidopteran, Uraba lugens

Abstract

Summary1. When invasive species are first detected in a new environment there is often a demand for information about the potential for the organism to spread and create impacts. Uraba lugens (Lepidoptera: Nolidae) is an Australian native moth that has invaded New Zealand in what are presumed to be two separate episodes. After U. lugens was found in Auckland in 2001 a climex ™ model was prepared to gauge the potential for the moth to spread and inflict damage in New Zealand. Inconsistencies in fitting model parameters to the then known native distribution, indicated that the known native distribution was probably incomplete, and that the unknown part of its range was critical for defining its likely range limits in New Zealand. 2. A synthetic sex pheromone trapping survey was used to ascertain the altitudinal and upper rainfall range limits of U. lugens in part of its native range in Australia. The survey extended the known range of U. lugens into higher-altitude and higher-rainfall zones of Tasmania. We used the expanded distribution information to refine a climex model, and to project the climate suitability for U. lugens with particular emphasis on New Zealand. 3. The projected climatic suitability of New Zealand indicates that the area likely to be at risk of invasion by U. lugens is considerably more extensive than was indicated from its historical distribution records in Australia. It now includes all the eucalypt forestry areas. Similarly, the global potential distribution covers the major eucalypt forestry regions of the world. 4. The minimum heat sum necessary to complete a generation for U. lugens that was associated with its range limits was considerably lower than that predicted by average development rates gained from constant temperature and daylength studies. Possible explanations for this anomaly are discussed. 5. Synthesis and applications . The lack of suitable data on the distribution of organisms is perhaps the single most common challenge for ecological climate modellers. Trapping along climatic gradients with a synthetic pheromone lure offers a cheap, rapid means of ascertaining the climatic distribution of suitable high profile insects.

Combining a Climatic Niche Model of an Invasive Fungus with Its Host Species Distributions to Identify Risks to Natural Assets: Puccinia psidii Sensu Lato in Australia

“…was found in slightly cooler locations in its introduced range (e.g., in southern California), than was known from within its presumed native range in South America and the Caribbean. However, in the absence of more extensive surveys such as gradsect trapping [56], the potential exists for P. psidii s.l. to be present, but undetected in cooler locations in the native range.…”

“…should be kept in mind when considering the modelled risks in the tropics. Should this aspect of the model become critical to some important decisions, then transect surveys using susceptible trap plants could be undertaken along critical climatic gradients [56]. The modelled poleward limits of P. psidii s.l.…”

CliMond: global high‐resolution historical and future scenario climate surfaces for bioclimatic modelling

“…The climate variables were monthly mean values from 1961-1990 of average daily temperature, daily temperature range and relative humidity, and average monthly totals of precipitation. Relative humidity values for 0900 and 1500 hours were estimated using the procedures described by Kriticos et al (2007). These 30¢ resolution data were then transformed into the CLIMEX .loc and .met file formats.…”

“…Following the method described by Kriticos et al (2007), projected values of monthly mean temperature at 0900 (T 0900 ) and 1500 hours (T 1500 ) were calculated from T mx and T mn (eqns 2 and 3) and projected values of relative humidity at 0900 (RH 0900 ) and 1500 hours (RH 1500 ) were calculated from vap, T mn , T 0900 and T 1500 for a given grid box (i), month (m), year (y), GCM (g) and SRES scenario (s).…”

The Stages of Invasion

“…Individual moths may fl y for only a kilometre or so, but wind transport (as for many insects) may be over much longer distances. Potential spread, with likely range in New Zealand evaluated though climate matching based on Australian data, was refi ned by surveys for adult moths in Tasmania using a synthetic pheromone (Kriticos et al 2007 ). In this example, the potential systematic use of such lures as a monitoring tool appeared useful in predicting range expansion.…”