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Many studies have focused on the impacts of climate change on biological assemblages, yet little is known about how climate interacts with other major anthropogenic influences on biodiversity, such as habitat disturbance. Using a unique global database of 1128 local ant assemblages, we examined whether climate mediates the effects of habitat disturbance on assemblage structure at a global scale. Species richness and evenness were associated positively with temperature, and negatively with disturbance. However, the interaction among temperature, precipitation and disturbance shaped species richness and evenness. The effect was manifested through a failure of species richness to increase substantially with temperature in transformed habitats at low precipitation. At low precipitation levels, evenness increased with temperature in undisturbed sites, peaked at medium temperatures in disturbed sites and remained low in transformed sites. In warmer climates with lower rainfall, the effects of increasing disturbance on species richness and evenness were akin to decreases in temperature of up to 9°C. Anthropogenic disturbance and ongoing climate change may interact in complicated ways to shape the structure of assemblages, with hot, arid environments likely to be at greatest risk.

In July 2019 an established infestation of Pheidole fervens was detected in Australia for the first time. An eradication program was conducted, and by November 2022 the ant had not been detected for 31 months so it was declared eradicated. This is the first time an exotic ant species has been eradicated from within Australia without other infestations of the same species being found in the meantime. Much of the achievement can be attributed to early detection of the incursion by Australia's National Border Surveillance program. [ABSTRACT FROM AUTHOR]

Here we report the establishment in Hawai'i of a trap-jaw ant, Odontomachus ruginodis, a species well known for its potent sting. In June 2017, a farmer on the island of Kaua'i reported "bites" from large ants and supplied a specimen to the U.S. Fish and Wildlife Service for identification. Additional specimens were found in 2019 and 2020 in multiple locations up to 5 kilometres away from the initial detection. Multiple morphological identifications were made and combined with CO1 genetic assessment confirmed the species to be Odontomachus ruginodis, which had not been recorded prior from Hawai'i. We argue that greater biosecurity protocols are needed in Hawai'i to prevent further incursions, especially the introduction of the red imported fire ant, Solenopsis invicta. [ABSTRACT FROM AUTHOR]

We present three studies assessing the efficacy and non-target impacts of multiple unregistered forms of hydrogel ant baits, as well as some co-use with the granular bait Antoff, that were experimentally used targeting Argentine ant, Linepithema humile, and yellow crazy ant, Anoplolepis gracilipes, within natural/semi-natural environments in Australia. The three studies varied greatly in design and treatment regimens, and were each conducted to address real-time learning needs while attempting to understand how best to use these experimental baits within the spatial, temporal and logistic limitations of three eradication programs. All studies involved broadscale applications of numerous forms of the baits, with greatly varying treatment regimens, coupled with before-after sampling of ant communities, as well as other soil invertebrates in one study. All studies found the baits were highly efficacious against both species, more so for A. gracilipes than L. humile. Eradication is considered to have been achieved for A. gracilipes in one treatment area with a triple treatment regimen, but not using different treatment regimens in other areas. Six treatments conducted approximately one week apart did not eradicate L. humile. Few non-target impacts were found, predominantly occurring only when sampling was conducted within days of a treatment, or at the end of six treatments of a high application rate. Instead, non-target species richness and composition were most often more affected by spatial location or sample time than treatment. Any treatment effects were non-persistent after 6–18 months. Hydrogel baits are likely to have significant roles to play for ant management and eradication. [ABSTRACT FROM AUTHOR]

Although there have been many attempts at eradicating exotic ant incursions, most efforts have been unsuccessful, and a lack of specific biological knowledge is believed to have been a major contributing factor. In early May 2013, an exotic ant species, Lepisiota frauenfeldi, was found for the first time in Australia. Identifying the species proved difficult, and little biological information about the species was available. In making the decision to eradicate and develop the treatment protocols, four assumptions were made about the ant’s biology. Here we detail rapid and basic research that was used to assess the assumptions underpinning the decision to eradicate, contribute to determine some eradication protocols for this understudied species, as well as how our understanding increased following the discovery of two other incursions of this species in Australia. The research found that all initial assumptions of the ant’s biology used in the original eradication plan were wrong. Distribution modelling found the ant could potentially inhabit a larger area than first thought, and updating the model with the subsequent incursions greatly increased the area of suitable climate in Australia. The ant’s foraging and reproductive regimes were not as expected, so too its nutrition pathways to queens, which had implications for the treatments. Our work serves as a clear warning for invasive species practitioners that management decisions that are based on assumptions, “gut feelings” or knowledge based on information from elsewhere in the world, or from other species, can be expected to be flawed. Rapid, small-scale and strategic research conducted on-site can enhance management outcomes. [ABSTRACT FROM AUTHOR]

Melophorus hirsutipes Heterick, Castanelli & Shattuck is a recently described taxon that was presented as occurring throughout most of mainland Australia and showing highly variable morphology. One highly variable character is sculpture, which is smooth and shiny in the type specimen but conspicuously scabrid and even rugulose in other forms. The scabrid and rugulose forms occur primarily in the monsoonal (seasonal) tropics of the northern third of the continent, a region that has recently been shown to be a global centre of ant diversity, but largely unrecognized as such because the great majority of species are undescribed. Here, we provide an integrated morphological, genetic (CO1) and distributional analysis of diversity within the scabrid and rugulose forms of M. 'hirsutipes'. We recognize 16 species among the 56 scabrid/rugulose specimens sequenced, along with four shiny or shagreenate species that are embedded within them. We conclude that Melophorus 'hirsutipes' is a highly diverse group of at least 30 species given the very patchy geographical coverage of sequenced specimens. Our findings provide further evidence that the total number of species in monsoonal Australia is likely in the several thousands, which would make it the world's richest known region for ant species. [ABSTRACT FROM AUTHOR]

Multiple new ant treatment products containing high volumes of sugar have recently been developed specifically for use in ant management programs. The presence of sugar in these products could potentially attract bees, and any such attractancy would likely be fatal given that these products typically contain general insecticides. To determine the risk of such products to bees I present four studies assessing bee attractancy to multiple matrices that are used to make these products. The trials were conducted across multiple years, seasons, and locations, containing various concentrations of sugar in multiple forms, using various experimental setups with many different bee hives, and multiple observers. Not a single bee was attracted to any matrix, nor were bees observed inspecting any matrix, and no bees fed on any matrix, irrespective of whether the matrices were placed close to hives and directly under bee flight paths, or out in areas where bees were feeding. This is in stark contrast to large numbers of bees that were feeding on flowers within the immediate vicinity of all of the matrices in the first two experiments, or flying over the arrays in experiments 3 and 4 travelling to and from other food sources. I present five suggestions for the discrepancy between the trials presented here and the general perception that bees are attracted to sugar. These matrices appear to be acceptable as a basis to make treatment products for broadscale use within ant management programs. However, it should be recognized that bees, and other non-target species, are indeed capable of feeding on these matrices. Therefore vigilance should still be maintained to identify special circumstances where bees may be killed when constituents are added to these matrices that do attract bees, or usage methods can adversely affect bees. [ABSTRACT FROM AUTHOR]

We document unrecognised diversity within the Tetramorium spininode Bolton group of the Australian monsoonal tropics, which has a single described species. At the time of its description, T. spininode was known from just two collections, but there have since been hundreds of collections from throughout monsoonal Australia. We document morphological and genetic (CO1) variation within the group's fauna of the Northern Territory (NT), in the centre of its range, where collection intensity has been highest. We recognise 20 species among 124 CO1-sequenced specimens, and 32 species in total from the NT. A key to these species is provided. The most intensively sampled regions within the NT are the mesic (>1000 mm mean annual rainfall) Top End in the far north (with 14 species) and the semi-arid (500–900 mm) Sturt Plateau region to its south (13 species). Only one species is known from both regions. Given such high regional turnover and highly patchy sampling, we estimate that at least 40 species of the T. spininode group occur in the NT. Similar diversity appears to occur in Western Australia, especially in the Kimberley region, but less in Queensland. Our findings suggest that the total number of species in the T. spininode group is likely to be around 100. Our study provides further evidence that monsoonal Australia is an unrecognised global centre of ant diversity. [ABSTRACT FROM AUTHOR]