Invasion success linked to physiological constraints of the Argentine ant

SCHILMAN, P.E.; LIGHTON, J.R.B. & HOLWAY, D.A.

White Mountain Research Station, Bishop, California, USA

Congreso; Physiological Ecology Meeting; 2004

It has been shown that rate of invasion and local abundance of the worldwide, abundant, and ecologically damaging ant species, Linepithema humile (Argentine ant) is strongly affected by soil moisture. We used a novel non-invasive technique that uses changes in gas composition to modulate spiracular conductance; this approach allowed us to estimate respiratory water loss in ant workers, but the method is applicable to tracheate arthropods with continuous gas exchange. Compared to five common ant species in southern California, the Argentine ant is highly prone to desiccation due to a higher respiratory water loss and area independent cuticular permeability. We conclude that the inability of Argentine ants to invade arid environments is due to this physiological constraint.