Activity ability of red imported fire ant workers after nest disturbed in different habitats of Southern China

The red imported fire ant Solenopsis invicta Buren is a highly aggressive invasive species which can become the dominant species in its newly invaded areas rapidly. This study aims to elucidate the activity levels of red imported fire ant workers in response to disturbances across different habitats. Ruler-mark method was applied to evaluate the activity capability of red imported fire ant workers after nest being disturbed in lawn, wasteland, banana orchard habitats during the summer and winter seasons. The higher average height which workers reached on ruler, the higher their activity capability had after nest being disturbed. The results indicated that the height reached by red imported fire ant workers was related to habitat type, seasonal variations, and the time elapsed after being disturbed. A pattern of initial increase followed by a decrease in height of reach was observed as time elapsed post-disturbance. Worker ants in the banana orchards had the highest height of reach in summer, reaching 29.37 cm at 100 seconds, with the highest activity, while those on winter lawns exhibited the lowest height of reach, reaching 1.1 cm at 20 seconds, with the lowest activity. After nest being disturbed, the average height workers reached was higher in summer than that in winter, meanwhile, the time that workers responded to disturbance was shorter in summer than that in winter. Multiple models were developed to describe the relationship between the average climbing height workers reached and duration after being disturbed in this study which can offer guidance for the scientific monitoring and precise control of red imported fire ant.