Detection and phylogenetic characterisation of novel Anaplasma and Ehrlichia species in Amblyomma triguttatum subsp. from four allopatric populations in Australia.

Anaplasma and Ehrlichia spp. are tick-borne pathogens that can cause severe disease in domestic animals, and several species are responsible for emerging zoonoses in the northern hemisphere. Until recently, the only members of these genera reported in Australia (A. marginale, A. centrale, and A. platys) were introduced from other continents, through the importation of domestic animals and their associated ticks. However, unique Anaplasma and Ehrlichia 16S rRNA gene sequences were recently detected for the first time in native Australian ticks, particularly in Amblyomma triguttatum subsp. ticks from southwest Western Australia (WA). We used molecular techniques to survey Am. triguttatum subsp. ticks from four allopatric populations in southern and western Australia for Anaplasma and Ehrlichia species, and described here the phylogeny of these novel organisms. An A. bovis variant (genotype Y11) was detected in ticks from two study sites; Yanchep National Park (12/280, 4.3%) and Barrow Island (1/69, 1.4%). Phylogenetic analysis of 16S rRNA and groEL gene sequences concluded that A. bovis genotype Y11 is a unique genetic variant, distinct from other A. bovis isolates worldwide. Additionally, a novel Ehrlichia species was detected in Am. triguttatum subsp. from three of the four study sites; Yanchep National Park (18/280, 6.4%), Bungendore Park (8/46, 17.4%), and Innes National Park (9/214, 4.2%), but not from Barrow Island. Phylogenetic analysis of 16S, groEL, gltA, and map1 gene sequences revealed that this Ehrlichia sp. is most closely related to, but clearly distinct from, E. ruminantium and Ehrlichia sp. Panola Mountain. We propose to designate this new species 'Candidatus Ehrlichia occidentalis'. Anaplasma bovis genotype Y11 and 'Candidatus E. occidentalis' are the first Anaplasma and Ehrlichia species to be recorded in native Australian ticks.

Thermoregulatory value of cracking-clay soil shelters for small vertebrates during extreme desert conditions.

Deserts exhibit extreme climatic conditions. Small desert-dwelling vertebrates have physiological and behavioral adaptations to cope with these conditions, including the ability to seek shelter. We investigated the temperature (T) and relative humidity (RH) regulating properties of the soil cracks that characterize the extensive cracking-clay landscapes of arid Australia, and the extent of their use by 2 small marsupial species: fat-tailed and stripe-faced dunnarts (Sminthopsis crassicaudata and Sminthopsis macroura). We measured hourly (over 24-h periods) the T and RH of randomly-selected soil cracks compared to outside conditions, during 2 summers and 2 winters. We tracked 17 dunnarts (8 Sminthopsis crassicaudata and 9 Sminthopsis macroura) to quantify their use of cracks. Cracks consistently moderated microclimate, providing more stable conditions than available from non-crack points, which often displayed comparatively dramatic fluctuations in T and RH. Both dunnart species used crack shelters extensively. Cracks constitute important shelter for small animals during extreme conditions by providing a stable microclimate, which is typically cooler than outside conditions in summer and warmer in winter. Cracks likely play a fundamental sheltering role by sustaining the physiological needs of small mammal populations. Globally, cracking-clay areas are dominated by agricultural land uses, including livestock grazing. Management of these systems should focus not only on vegetation condition, but also on soil integrity, to maintain shelter resources for ground-dwelling fauna.

Pastoralists' perceptions of biodiversity and land management strategies in the arid Stony Plains region of South Australia: implications for policy makers.

The implementation of rangeland biodiversity management strategies relies on the engagement and participation of key stakeholders, including local pastoralists (ranchers). Understanding pastoralists' knowledge of biodiversity, as well as their attitudes towards and perceptions of biodiversity management strategies, is fundamental for the development of efficacious rangeland management. This paper examines perceptions of biodiversity and land management strategies held by pastoralists in the Stony Plains region (SPR) of South Australia and reports on a survey, consisting of 45 questions, delivered to lessees and/or managers of pastoral leases within or on the edge of the SPR. Respondents generally agreed with prescribed land management strategies, but agreement did not mean that strategies were being implemented. The purchase of pastoral leases by government and/or conservation groups for biodiversity purposes was opposed strongly, which may present a barrier to collaborative land management. Pastoralists strongly agreed with several listed threats to biodiversity, but their feelings on climate-related threats were less strong. Attitudes to climate may have been influenced by above-average rainfall experienced during and preceding the survey period and by the climatic variability that characterises arid rangelands. Biodiversity conservation and the pastoral industry rely on collaborative rangeland management, non-bureaucratic communication, and an understanding among stakeholders of the attitudes and perceptions of other natural-resource users.

Human perception and awareness of ticks in a South Australian rural community and implications for management of Amblyomma triguttatum triguttatum.

The ornate kangaroo tick, Amblyomma triguttatum triguttatum, is invasive on Yorke Peninsula, South Australia. To assess the potential for developing comprehensive management strategies for the species, we mailed 1,000 surveys to Yorke Peninsula residents to investigate community perceptions of ticks, gather information on tick-host ecology, and assess whether or not occupation and length of residence affected whether residents had seen ticks. The response rate was 32%; most respondents (63%) had not seen ticks on Yorke Peninsula. Of those who had (n = 104), 56% had seen ticks on animals, especially lizards (31%) and kangaroos (20%); 50% had seen ticks on humans. Of the 64 respondents who believed places on Yorke Peninsula had many ticks, 56% identified Innes National Park and 75% areas on southern Yorke Peninsula. The likelihood of seeing ticks was not related to occupation. Whether respondents had seen ticks was related to length of residence on Yorke Peninsula (<10 years = 23.6%, 10-30 years = 44.0%, 31-50 years = 47.6%, 51-70 years = 30.9%, 71+ years = 21.4%). The number of respondents who had seen ticks on humans suggests that tick-borne diseases could become a public health issue on Yorke Peninsula. This finding is of particular concern because A. t. triguttatum is implicated in the epidemiology of Q fever in Queensland. Finally, respondents were unaware of the responsibility for tick management, which demonstrates a need for collaboration amongst stakeholders.

Hosts of the exotic ornate kangaroo tick, Amblyomma triguttatum triguttatum Koch, on southern Yorke Peninsula, South Australia.

Amblyomma triguttatum triguttatum is assumed to be endemic to south-western Western Australia (including Barrow Island), Queensland (excluding Cape York Peninsula), and New South Wales, south to Dubbo and Barham. The species has been recorded on a range of mammalian hosts including macropods and domestic animals. In Queensland, A. triguttatum triguttatum is implicated in the epidemiology of Q fever. In 2000, the species was detected on southern Yorke Peninsula in South Australia. We aimed to identify A. triguttatum triguttatum's hosts through trapping, sampling of carcasses, and opportunistic capture of vertebrates on Yorke Peninsula. A. triguttatum triguttatum was removed from black rats (Rattus rattus), wild rabbits (Oryctolagus cuniculus), western grey kangaroos (Macropus fuliginosus), Tammar wallabies (M. eugenii eugenii), domesticated cats and dogs, and humans. Before this study, A. triguttatum triguttatum had not been found on black rats or rabbits in the wild. This research has implications for the management of wildlife, livestock, and visitors on Yorke Peninsula. The potential for A. triguttatum triguttatum to spread to other areas of Yorke Peninsula and South Australia is considerable, as visitors (tourists) to southern Yorke Peninsula report the presence of ticks both on themselves and among camping equipment on arriving home.

Seasonal density fluctuations of the exotic ornate kangaroo tick, Amblyomma triguttatum triguttatum Koch, and its distribution on Yorke Peninsula, South Australia.

The ornate kangaroo tick, Amblyomma triguttatum triguttatum, was recently recorded on southern Yorke Peninsula, South Australia. We examined seasonal fluctuations in A. triguttatum triguttatum life stages (adult, larva, and nymph) and its distribution on the peninsula. We used in situ CO2 traps and dragging cloths to determine monthly fluctuations in free-living ticks at four sites at Innes National Park from January to December 2006, and to determine the tick's distribution on wider Yorke Peninsula. At each site, 166 m2 of ground surface were directly sampled with cloths, representing 16 1-m2 CO2 stations and three 1-m-wide 50-m transects. Adult A. triguttatum triguttatum were present in January and February and from August to December, with a peak (n=54) occurring in November. Larvae were present from February to August, with their highest density (n=3067) detected in March. Nymphs were collected from January to April and from August to December, with the highest density (n=61) detected in September. Overall, A. triguttatum triguttatum numbers were highest in March when larvae peaked, and few ticks were detected in January (summer) or July (winter). Ticks occurred at several sites on southern Yorke Peninsula, supporting their invasive status.