Raft formation by the red imported fire ant, Solenopsis invicta
Department of Entomology, 404 Life Science Building Louisiana State University Baton Rouge, Lousiana 70803
Abstract
The raft behavior of the invasive red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae), has been documented for over a century. However, no rigorous tests have been performed elucidating the structure, limits, and important characteristics of this behavior. Rafting makes S. invicta competitive in both native and foreign environments. Further understanding of this behavior will provide critical advancement to the comprehension of this ant’s global invasion ecology.
Though speculations exist, no one has looked at the movements of individuals within the raft formation, the longevity of rafts, raft success rate, or the importance of different life stages and varying types of adults to raft formation. Furthermore, bubble use has been extensively studied in arthropods, but it has never been documented in social insects. The use of bubbles as a means of floatation has never before been noted in raft formation.
This study shows that ants trapped under water escape by lifting themselves to the air-water interface through the use of bubbles collected from submerged substrate. The presence of larvae was noted to increase colony survival and maximize raft longevity due in part their ability to hold bubbles under hydrophobic setae.
Keywords: bubbles, bubble elevator, flood adaptation, plastron
Abbreviations:PR, pre-rafting; RM, post-rafting moving; RS, post-rafting stationary
Correspondence:
a badam24@tigers.lsu.edu,
b* lhooper@agcenter.lsu.edu,
c rstrecker@agcenter.lsu.edu, *Corresponding author
Editor: Mario Muscedere was Editor of this paper.
Received: 23 March 2011 | Accepted: 17 May 2011 | Published: 19 December 2011
Copyright: This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.
ISSN: 1536-2442 | Volume 11, Number 171
Adams BJ, Hooper-Bùi LM, Strecker RM, O’Brien DM. 2011. Raft formation by the red imported fire ant, Solenopsis invicta. Journal of Insect Science 11:171 available online: insectscience.org/11.171
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