Zoological Studies

Vol. 61, 2022

(update: 2022.4.21)

Searching Behavior in the Tropical Fire Ant Solenopsis geminata (Hymenoptera: Formicidae)

Li‑Chuan Lai1,*, Tzu-Yen Chao1, and Ming-Chung Chiu2

1Department of Ecological Humanities, Providence University, 200, Sec. 7, Taiwan Boulevard, Shalu Dist., Taichung City 43301, Taiwan. *Correspondence: E-mail: lclai@pu.edu.tw (Lai)
2Department of Biology National Changhua University of Education, Jin-De Campus, No.1, Jin-De Road, Changhua City 55007, Taiwan. E-mail: b93612019@ntu.edu.tw (Chiu)

Received 19 December 2021 / Accepted 13 April 2022
Communicated by John Wang

Social insects have evolved different search strategies to find target objects in unknown environments. In the present study, the searching behavior of the tropical fire ant Solenopsis geminata was investigated in a circular arena. The average time, search path, speed, and search patterns of worker ants in a circular arena were determined. The results showed that fire ant workers followed six major search patterns. The variation in the searching patterns of workers may explain the different levels of exploration. Most workers (56.8%) tended to search in small loops and progressively increase the search area size. These workers mostly turned in one direction, either clockwise or counterclockwise. The number of workers whose turning directions were consistent was significantly higher than that of workers which changed the turning directions. Moving speed was also higher in workers who maintained their turning directions than in those that changed directions. We thus propose that following search patterns consisting of loops of increasing size may be an effective strategy. The tropical fire ant S. geminata is a globally invasive species that was introduced to Taiwan 40 years ago and has continued to threaten residents. Based on behavioral studies of S. geminata, we may gain a better understanding of their exploratory behavior in the ecosystem in Taiwan.

Key words: Solenopsis geminata, Searching behavior, Searching patterns, Loops, Invasive species.

Citation: Lai LC, Chao TY, Chiu MC. 2022. Searching behavior in the tropical fire ant Solenopsis geminata (Hymenoptera: Formicidae). Zool Stud 61:26.