Vanderwoude, C, Andersen, A.N. and House, A.P.N. , 1997. Ant communities as bio-indicators in relation to fire management of spotted gum (Eucalyptus maculata Hook.) forests in south-east Queensland. Memoirs of the Museum of Victoria 56(2): 671-675. As a pilot test of the potential for using ant communities as bio-indicators in forest monitoring programs, the effects of different fire regimes on ant community structure were studied at Bauple State Forest in 1 994 and 1 995. Three sites had been subjected to long-term burning regimes of: annual burning: periodic burning(2-3 years); and no burning. Two grids of pitfall traps were established in each compartment, and ants were sampled monthly between May 1 994 and April 1 995. A total of 88 species from 42 genera were recorded, with 74 species found from the annually burned site, 63 from the periodically burned site, and 43 from the unburned site. The relative abundance of Eyrean (arid) taxa was particularly high (36%) and that of Bassian (cool temperate) taxa low (8%) at the annually burned site, with the reverse true for the unburned site (14% and 20% respectively). Burning frequency also affected the dominance of functional groups. The relative abundance of Dominant Dolichoderinae (species of Iridomvrmex) was positively related to fire frequency, while Opportunists (mostly species o(Rhvtidoponcra) comprised 65% of all ants at the unburned site, but only 16% at the annually burned site. These site differences conform to known ant-firehabitat relationships elsewhere in Australia. We have not only shown that ant communities are sensitive to fire management practices in Bauple State Forest, but have demonstrated that an effective ant sampling program is a practicable option.

No abstract

The discovery of the Red Imported Fire ants (Solenopsis invicta) in Brisbane on 22 February 2001 sent shock waves through urban and rural communities alike. This article is an attempt to address the often repeated question ‘What will become of Australia's unique fauna if they spread along Australia's eastern seaboard?

The introduced tramp ant, Pheidole megacephala, is a well‐known pest of urban areas and coastal dune ecosystems in eastern Australia. Until recently, establishment and spread of P. megacephala colonies has been regarded as likely only in disturbed areas. Here we describe the extent of an established colony of P. megacephala in a long undisturbed open forest near Maryborough in southeast Queensland and compare ant community structure with those of nearby uninfested sites. Tuna baiting revealed three distinct zones: (i) a zone totally dominated by P. megacephala (at least 10 ha) where few other ant ant species were detected; (ii) a zone where P. megacephala was absent and many other ant species were found; and (iii) a zone where opportunists (species of Ochetellus and Paratrechina) competed with P. megacephala at baits. Pitfall trapping over a 9‐month period resulted in 12 species being recorded at the infested site, compared with a mean of 25 species recorded at adjoining uninfested forest. Over 94% of ants recorded in pitfalls at the infested site were P. megacephala. Most notably, P. megacephala had completely displaced dominant Dolichoderines (species of Iridomyrmex), subordinate Camponotini (species of Camponotus, Opisthopsis and Polyrhachis) and other species of Pheidole which are common at forest sites.

The introduced tramp ant, Pheidole megacephala, is a well-known pest of urban areas and coastal dune ecosystems in eastern Australia. Until recently, establishment and spread of P. megacephala colonies has been regarded as likely only in disturbed areas. Here we describe the extent of an established colony of P. megacephala in a long undisturbed open forest near Maryborough in southeast Queensland and compare ant community structure with those of nearby uninfested sites. Tuna baiting revealed three distinct zones: (i) a zone totally dominated by P. megacephala (at least 10 ha) where few other ant ant species were detected; (ii) a zone where P. megacephala was absent and many other ant species were found; and (iii) a zone where opportunists (species of Ochetellus and Paratrechina) competed with P. megacephala at baits. Pitfall trapping over a 9-month period resulted in 12 species being recorded at the infested site, compared with a mean of 25 species recorded at adjoining uninfested forest. Over 94% of ants recorded in pitfalls at the infested site were P. megacephala. Most notably, P. megacephala had completely displaced dominant Dolichoderines (species of Iridomyrmex), subordinate Camponotini (species of Camponotus, Opisthopsis and Polyrhachis) and other species of Pheidole which are common at forest sites.

The red imported fire ant, Solenopsis invicta , a damaging invasive pest,

Quantifying the potential spread and density of an invading organism enables decision-makers to determine the most appropriate response to incursions. We present two linked models that estimate the spread of Solenopsis invicta Buren (red imported fire ant) in Australia based on limited data gathered after its discovery in Brisbane in 2001. A stochastic cellular automaton determines spread within a location (100 km by 100 km) and this is coupled with a model that simulates human-mediated movement of S. invicta to new locations. In the absence of any control measures, the models predict that S. invicta could cover 763 000-4 066 000 km 2 by the year 2035 and be found at 200 separate locations around Australia by 2017-2027, depending on the rate of spread. These estimated rates of expansion (assuming no control efforts were in place) are higher than those experienced in the USA in the 1940s during the early invasion phases in that country. Active control efforts and quarantine controls in the USA (including a concerted eradication attempt in the 1960s) may have slowed spread. Further, milder winters, the presence of the polygynous social form, increased trade and human mobility in Australia in 2000s compared with the USA in 1940s could contribute to faster range expansion.

The biogeography and structure of ant communities were examined over a 12-month period at a dry open eucalypt forest in south-eastern Queensland. Three sites were monitored, each with a distinct long-term burning history: burned annually since 1952, burned periodically since 1973, and unburned since 1946. A total of 89 species from 42 genera was recorded over all trapping periods, with the richest genera being Iridomyrmex, Camponotus and Pheidole, each with eight species. Site species richness was 74, 63 and 43, respectively, at the annually burned, periodically burned and the unburned site. We compared the ant community in this forest with those at other forested sites in eastern Australia. Overall, the south-eastern Queensland community was located on the overlap between the Bassian and Torresian zones (not dominated by either element), while the functional-group composition resembled those of both tropical savannas and cool-temperate woodlands. There were readily discernible differences between sites in terms of biogeographical and functional-group composition; and between the unburned site and both burned sites in terms of abundance and species richness. The relative abundance of Iridomyrmex spp. increased with burning frequency while the relative abundance of Bassian species decreased with burning frequency. Species richness and abundance at the burned sites were similar, but substantially higher than at the unburned site. The community characteristics of the three sites were readily distinguishable, indicating that ant communities may play a valuable role in detecting ecological changes in forested landscapes in south- eastern Queensland.