
%0 Journal Article
%A Stevens, M. M. 
%A James, D. G. 
%A O'Malley, K. J. 
%A Coombes, N. E. 
%T Seasonal variations in foraging by ants (Hymenoptera : Formicidae) in two New South Wales citrus orchards
%J Australian Journal of Experimental Agriculture
%D 1999/01/27
%V 38
%N 8
%P 889-896
%K 
%R https://doi.org/10.1071/EA98076
%U https://www.publish.csiro.au/paper/EA98076 
%X Summary. Pitfall traps were used to monitor the seasonal activity of ants in 2 citrus orchards in the Murrumbidgee Irrigation Area of south-western New South Wales for 22&#8211;24 months (November 1992&#8211;August/October 1994). Twenty-four species were recorded (22 species at Yanco and 18 species at Cudgel), with Iridomyrmex rufoniger group species being numerically dominant at both sites (63 and 59% of total captures at Yanco and Cudgel respectively). Meat ants, Iridomyrmex purpureus (F.Smith), were a significant (9%) component of trap captures at Yanco where regular soil cultivation was practised, but were less common (&#60;1% of captures) at Cudgel. Sample species richness was generally greater at the Yanco site (mean 9.3 species per trapping interval compared with 6.6 at Cudgel). Total ant captures and sample species richness showed a positive correlation with mean daily temperatures over trapping intervals. Variations in seasonal activity were shown by the numerically dominant species, with 2 distinct patterns being evident. Whilst all taxa were less active during winter, some species &#91;I. rufoniger group sp. 2, Pheidole sp., Rhytidoponera metallica (F.Smith)&#93; continued to forage, albeit at reduced levels. Other species of Iridomyrmex including I. rufoniger group sp. 1 and I. purpureus ceased foraging almost entirely during June&#8211;September. Iridomyrmex species are known to interfere with the biological control of honeydew-producing insects in citrus orchards, and our results indicate that ant control programs in southern New South Wales should be initiated in late August&#8211;early September to achieve optimal results. 
