The Thermal Breadth of Nylanderia fulva (Hymenoptera: Formicidae) Is Narrower Than That of Solenopsis invicta at Three Thermal Ramping Rates

Scientists are one step closer to predicting the non-native range of the tawny crazy ant, Nylanderia fulva. Native to South America, this ant has invaded most southeastern US states where its large colonies have displaced native species and have become a major disturbance to homeowners. Determining how far an invasive species may spread is critical to directing quarantine and management efforts. One way that scientists can predict the limits of an invaders range is by determining its critical thermal limits, or the maximum hottest and coldest temperatures that it could withstand. These measurements can then be entered into complex mathematical models along with weather data to predict how far the invasive species may expand its range.  

Entomologists at the University of Florida measured the critical thermal limits of the tawny crazy ant and another invader, the red imported fire ant. They found that the crazy ant had a narrower thermal breadth compared to the fire ant, meaning the crazy ant was less tolerant of both hot and cold temperatures. What these findings may suggest is that the tawny crazy ant’s invasive range will be more restricted to warmer regions than the red imported fire ant. These data will be helpful for developing predictive models that estimate the future spread of both invasive ants, and will be important to improving their management and quarantine efforts.  

This research was published in the Journal of Medical Entomology.