Search

BackgroundInvasive species threaten the productivity and stability of natural and managed ecosystems. Predicting the spread of invaders, which can aid in early mitigation efforts, is a major challenge, especially in the face of climate change. While ecological niche models are effective tools to assess habitat suitability for invaders, such models have rarely been created for invasive pest species with rapidly expanding ranges. Here, we leveraged a national monitoring effort from 543 sites over 3 years to assess factors mediating the occurrence and abundance of brown marmorated stink bug (BMSB, Halyomorpha halys), an invasive insect pest that has readily established throughout much of the United States.ResultsWe used maximum entropy models to estimate the suitable habitat of BMSB under several climate scenarios, and generalized boosted models to assess environmental factors that regulated BMSB abundance. Our models captured BMSB distribution and abundance with high accuracy, and predicted a 70% increase in suitable habitat under future climate scenarios. However, environmental factors that mediated the geographical distribution of BMSB were different from those driving abundance. While BMSB occurrence was most affected by winter precipitation and proximity to populated areas, BMSB abundance was influenced most strongly by evapotranspiration and solar photoperiod.ConclusionOur results suggest that linking models of establishment (occurrence) and population dynamics (abundance) offers a more effective way to forecast the spread and impact of BMSB and other invasive species than simply occurrence-based models, allowing for targeted mitigation efforts. Implications of distribution shifts under climate change are discussed. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Biological control is often a key component of management strategies for invasive species. Yet, the effectiveness of biological control can be limited by a poor understanding of natural enemy ecology. To overcome this, habitat suitability models can predict distributions of invasive species and identify areas of potential overlap between invaders and natural enemies to guide biological control. Here we used data from a coordinated national monitoring network and a novel modeling method that incorporates physiology into correlative niche models to predict potential distributions of the brown marmorated stink bug, Halyomorpha halys, and two natural enemies (a parasitoid, Trissolcus japonicus, and a microsporidian, Nosema maddoxi) in current and future climates (2070s). We show all three species have broad similarity in habitat suitability, with especially high overlap in the mid-Atlantic and southeastern US where H. halys populations were first established. Each species will likely expand their range across the northern US in the future, but the overlap between species may decrease. In much of the central and southeastern US, H. halys may decrease its range over time, although natural enemies may be less impacted, and overlap between species may increase. Our study shows that biological control provided by T. japonicus and N. maddoxi could be key for managing H. halys given their overlapping niches, and our models can aid in delineating areas where biocontrol may be most effective. Our method of linking field data with correlative niche models can also be used for other insects. [ABSTRACT FROM AUTHOR]

BACKGROUND Commercial vegetable production in the United States of America (USA) often relies on foliar insecticide sprays for managing key insect pests. However, foliar applications of insecticides have a number of drawbacks to the health of consumers, farmworkers and the environment. Drip chemigation is the application of pesticides to the soil through trickle (drip) irrigation systems, and can overcome a number of the drawbacks typical of foliar insecticide applications. RESULTS: We conducted a two‐year study in five commercial fields of staked tomatoes in western North Carolina to compare the efficacy, economics and environmental impact of drip chemigation versus foliar sprays. Drip chemigation significantly reduced insecticide inputs, utilized more selective and environmentally compatible insecticides, and reduced the time lost to reentry intervals, while maintaining comparable efficacy and economic returns. CONCLUSIONS: Drip chemigation was an effective tool for managing key insect pests, provided a broad range of human and environmental health benefits, and will likely become increasingly cost‐effective in the future as insecticide patents expire and more insecticide options become available. [ABSTRACT FROM AUTHOR]