No abstract

The Asian vinegar fly Drosophila suzukii (spotted wing Drosophila [SWD]) has emerged as a major invasive insect pest of small and stone fruits in both the Americas and Europe since the late 2000s. While research efforts have rapidly progressed in Asia, North America, and Europe over the past 5 years, important new insights may be gained in comparing and contrasting findings across the regions affected by SWD. In this review, we explore common themes in the invasion biology of SWD by examining (1) its biology and current pest status in endemic and recently invaded regions; (2) current efforts and future research needs for the development of predictive models for its geographic expansion; and (3) prospects for both natural and classical (=importation) biological control of SWD in invaded habitats, with emphasis on the role of hymenopteran parasitoids. We conclude that particularly fruitful areas of research should include fundamental studies of its overwintering, host-use, and dispersal capabilities; as well as applied studies of alternative, cost-effective management techniques to complement insecticide use within the integrated pest management framework. Finally, we emphasize that outreach efforts are critical to effective SWD management by highlighting successful Communicated by M. Traugott. Electronic supplementary materialThe online version of this article (strategies and insights gained from various geographic regions.Keywords Biological control Á Drosophila Á Frugivore Á Integrated pest management Á Invasion biology Key message• Spotted wing Drosophila (SWD) is a major invasive pest of soft fruits in the Americas and Europe. • We review the current global distribution and economic impacts of SWD, develop models for predicting its further spread, and discuss the prospects for biological control of this pest. • The following research areas into SWD biology appear particularly promising: its biology at low temperatures, the dispersal and migratory abilities of adults, and exploration in Asian regions for potential classical biological control agents.

With the current advances in insect population modelling, the need for more accurate simulation of temperature-dependent growth rates has become vital. The day-degree concept, with its linear temperature–rate relationship, has not been adequate for simulation of field populations under highly variable temperature conditions. Similarly, several of the non-linear relationships proposed in the past (Janisch’s catenary, parabola) have also been inadequate. All of these relationships produce large errors at temperature extremes.This paper presents a comparison of various functions which have been used for developmental time estimation and an algorithm for a sigmoid function which can be used in simulations having either a calendar or a physiological time base. Validation of the algorithm is presented for three insect species.

Ratio—dependent models of predators and prey are approximations of the biology of resource acquisition and allocation and their consequences for population birth and death rates. A demand—driven functional response model that has a physiological basis in mass (energy) dynamics is reviewed (i.e., the metabolic pool model), and its obvious links to the logistic model are outlined. To demonstrate the utility of this approach, a distributed maturation time age—structure model of the dynamics of A. J. Nicholson's classic laboratory population data on the sheep blow fly (Lucilia cuprina Weidman) is developed. The model provides sufficient information on the dynamics of the intermediate life stages to show that the blow fly oscillations were due to the effects of larval competition for food on size, fecundity, and pupation success. These results agree with Nicholson's conclusions. The advantage of this model, in contrast to prior models, is that the dynamics emerge by considering the processes of resource acquisition and allocation as they affect growth, reproduction, and survival. No explicit time delays, which automatically lead to oscillations, were included. Lastly, the notions of the metabolic pool model are found in Nicholson's original model for equilibrium population density. The metabolic pool paradigm in an age—structure setting is used to model the tri—trophic dynamics of Acyrthosiphon aphids in an alfalfa ecosystem. The model explains the role of the various natural enemies in the regulation of the aphids.

The Mediterranean Basin is a climate and biodiversity hot spot, and climate change threatens agro-ecosystems such as olive, an ancient drought-tolerant crop of considerable ecological and socioeconomic importance. Climate change will impact the interactions of olive and the obligate olive fruit fly (Bactrocera oleae), and alter the economics of olive culture across the Basin. We estimate the effects of climate change on the dynamics and interaction of olive and the fly using physiologically based demographic models in a geographic information system context as driven by daily climate change scenario weather. A regional climate model that includes fine-scale representation of the effects of topography and the influence of the Mediterranean Sea on regional climate was used to scale the global climate data. The system model for olive/olive fly was used as the production function in our economic analysis, replacing the commonly used production-damage control function. Climate warming will affect olive yield and fly infestation levels across the Basin, resulting in economic winners and losers at the local and regional scales. At the local scale, profitability of small olive farms in many marginal areas of Europe and elsewhere in the Basin will decrease, leading to increased abandonment. These marginal farms are critical to conserving soil, maintaining biodiversity, and reducing fire risk in these areas. Our fine-scale bioeconomic approach provides a realistic prototype for assessing climate change impacts in other Mediterranean agro-ecosystems facing extant and new invasive pests.ecological impacts | economic impacts | species interactions | Olea europaea | desertification