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The polyphagous Asian vinegar fly Drosophila suzukii (spotted wing Drosophila) is a native of Eastern and Southeastern Asia. It emerged as an important invasive insect pest of berries and stone fruits in the Americas and Europe beginning in 2008. Species distribution models are commonly used for analyzing the extant and potential range expansion of invasive species. Previous modeling efforts for D. suzukii include a degree-day model, a MaxEnt ecological niche model, a demographic model incorporating the effects of temperature, and a preliminary mechanistic physiologically-based demographic model (PBDM). In the present analysis, we refine the PBDM for D. suzukii based on biological data reported in the literature. The PBDM is used to assess the effects of temperature and relative humidity from a recently published global climate dataset (AgMERRA) on the prospective geographic distribution and relative abundance of the pest in the USA and Mexico, and in Europe and the Mediterranean Basin. Our focus is on areas of recent invasion and of predicted higher invasiveness in these areas. Although the species is native to Asia and is of putative temperate origins, it has established in subtropical to north temperate zones worldwide where it infests a wide range of wild and domesticated berries and stone fruits. The model captures the observed phenology of D. suzukii at specific locations, as well as the potential geographic distribution and relative favorability across larger regions. The main limiting factor is cold winter temperature in northern areas, though high temperatures and low relative humidity may be limiting in arid areas. The effect of greater cold tolerance in winter morph adults is explored.

The highly polyphagous light brown apple moth (LBAM) (Epiphyas postvittana (Walk.): Tortricidae) is indigenous to Australia and was first found in California in 2006. It is currently found in 15 coastal counties in California, but nowhere has it reached outbreak status. The USDA projects the geographic range of LBAM will include much of Arizona and California and the southern half of the US, which together with economic estimates of potential crop losses have been used as the rationale for an eradication program in California. We report a temperature-driven demographic model to predict the likely distribution and relative abundance of LBAM using the detailed biology reported by Danthanarayana and colleagues, and climate data from 151 locations in California and Arizona for the period 1995–2006. The predictions of our model suggest that the near coastal regions of California are most favorable for LBAM, the northern Central Valley of California being less favorable, and the desert regions of Arizona and California being unfavorable. The model also predicts that LBAM populations can develop at two of the hottest locations in SE Australia where it is has long been known to occur. This reassessment of the potential distribution of LBAM in California and Arizona suggests that its likely ecological and economic impacts would be less than previously assessed by USDA and that its current pest status warrants re-evaluation.

The Mediterranean Basin is a climate change and biological invasion hotspot where recent warming is facilitating the establishment and spread of invasive species, one of which is the highly destructive South American tomato leafminer (Tuta absoluta). This pest recently invaded the Mediterranean Basin where it threatens Solanaceous crops. Holistic approaches are required to project the potential geographic distribution and relative abundance of invasive species and hence are pivotal to developing sound policy for their management. This need is increasing dramatically in the face of a surge in biological invasions and climate change. However, while holistic analyses of invasive species are often advocated, they are rarely implemented. We propose that physiologically based demographic models (PBDMs) in the context of a geographic information system (GIS) can provide the appropriate level of synthesis required to capture the complex interactions basic to manage invasive species such asT. absoluta. We review the PBDMs for two invasive flies, and use them as a basis for assessing the biological data available for the development of a PBDM forT. absoluta, and in the process identify large data gaps that using the PBDM as a guide can be easily filled. Other components for an ecologically based management program for this pest (habitat modification, natural and classical biocontrol, pheromones, and others) are also reviewed. The development of a PBDM forT. absolutawould provide the basis for an interdisciplinary agroecological synthesis of the problem and the role different control tactics would play in region-specific control of the pest. [ABSTRACT FROM AUTHOR]

The invasive Asian citrus psyllid (Diaphorina citri Kuwayama) is the vector of the bacterial pathogen ('Candidatus Liberibacter asiaticus') that is the putative causal agent of citrus greening disease (Huanglongbing disease) in citrus in many areas of the world. The capacity to predict the potential geographic distribution, phenology and relative abundance of the pest and disease is pivotal to developing sound policy for their management. A weather-driven physiologically based demographic model (PBDM) system was developed to summarize the available data in the literature, and used to assess prospectively the geographic distribution and relative yield of citrus, the relative densities of the psyllid, its parasitoid (Tamarixia radiata Waterston), and the potential severity of citrus greening disease in North America and the Mediterranean Basin. The potential for natural and biological control of citrus psyllid was examined prospectively. [ABSTRACT FROM AUTHOR]

The polyphagous European grapevine moth Lobesia botrana (Den. & Schiff.) is the principal native pest of grape berries in the Palearctic region. It was found in Napa County, California, in 2009, and it has subsequently been recorded in an additional nine counties, despite an ongoing eradication programme. The present study aimed to assess prospectively its potential geographical distribution and relative abundance in California and the continental U.S.A. A subsidiary goal was to provide explanation for timing control measures., Data from the European literature were used to formulate and parameterize a holistic physiologically-based demographic model for L. botrana. This model was linked to an extant mechanistic model of grapevine phenology, growth and development that provides the bottom-up effects of fruiting phenology, age and abundance on L. botrana dynamics. Fruit age affects larval developmental rates, and has carryover effects on pupal development and adult fecundity. Also included in the model were the effects of temperature on developmental, survival and fecundity rates., Observed daily weather data were used to simulate the potential distribution of the moth in California, and the continental U.S.A. The relative total number of pupae per vine per year was used as the metric of favourability at all locations. The simulation data were mapped using grass gis ()., The model predicts L. botrana can spread statewide with the highest populations expected in the hotter regions of southern California and the lower half of the Central Valley. In the U.S.A., areas of highest favourability include south Texas, and much of the southeast U.S.A., The effects of a warmer climate on pest abundance were explored by increasing observed mean temperatures 2° and 3 °C. L. botrana abundance is expected to increase in northern California and in the agriculturally rich Central Valley but to decrease in the hot deserts of southern California where summer temperatures would approach its upper thermal limit., Analysis of the timing of mating disruption pheromone for control of L. botrana suggests the greatest benefit would accrue by targeting adults emerging from winter diapause pupae and the flight of first summer adults. [ABSTRACT FROM AUTHOR]

The capacity to predict the geographic distribution and relative abundance of invasive species is pivotal to developing policy for eradication or control and management. Commonly used methods fall under the ambit of ecological niche models (ENMs). These methods were reviewed and shortcomings identified. Weather-driven physiologically based demographic models (PBDMs) are proposed that resolve many of the deficiencies of ENMs. The PBDM approach is used to analyze the invasiveness of the polyphagous glassy-winged sharpshooter (Homalodisca vitripennis [Germar] ), a pest native to the southeastern United States and northeastern Mexico that extended its range into California in 1989. Glassy-winged sharpshooter vectors the pathogenic bacterium, Xylella fastidiosa (Wells) that causes Pierce's disease in grape and scorch-like diseases in other plants. PBDMs for glassy-winged sharpshooter and its egg parasitoids (Gonatocerus ashmeadi Girault and G. triguttatus Girault) were developed and linked to a PBDM for grape published by Wermelinger et al. (1991). Daily weather data from 108 locations across California for the period 1995-2006 were used to drive the PBDM system, and GRASS GIS was used to map the simulation results. The geographic distribution of glassy-winged sharpshooter, as observed, is predicted to be largely restricted to the warm areas of southern California, with the action of the two egg parasitoids reducing its abundance >90%. The average indispensable mortality contributed by G. triguttatus is <1%. A temperature-dependent developmental rate model for X. fastidiosa was developed that suggests its geographic range is also limited to the warm inland areas of southern California. Biological control of glassy-winged sharp- shooter further decreases the pathogen's relative range. Climate warming scenarios of + 2°C and +3°C suggest that the distribution and severity of glassy-winged sharpshooter and X. fastidiosa will increase in the agriculturally rich central valley of California. The utility of holistic analyses for formulating control policy and tactics for invasive species is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Adapted species in nature are assumed to have solved renewable resource management problems, and this is examined here using a physiologically based model of energy acquisition and allocation. Newly established invasive species are merely in an early phase of this process in their new environment. Analogies between the economies of humans and other species are used to develop an objective function for individual utility of energy allocation. The objective function includes the physiologically based population dynamics models of the consumer and resource species in a food chain as constraints. The model applies to all trophic levels in a food chain including human harvesting of renewable resources (see also Regev et al. (Regev, U., Gutierrez, A.P., Schreiber, S., Zilberman, D., 1998. Biological and Economic Foundation of Renewable Resource Exploitation. Ecological Economics. 26 (3), 227-242.)). Specifically, the analysis: [(1)] Attempts to combine ecological and economic theory; [(2)] Points out the importance of time frame in the two economies (evolutionary vs. market time); [(3)] Examines the effects of expected uncertainty due to environmental hazards in defining energy acquisition and allocation strategies in two invasive aphid species at the extremes of so called r- and K-strategies and the well adapted Central American cotton–cotton bollweevil system; [(4)] Evaluates the effects of changes in behavioral and physiological parameters and environmental degradation on the abundance of resource and consumer species. [Copyright &y& Elsevier]