Ant biodiversity and its environmental predictors in the North Kimberley region of Australia’s seasonal tropics

Northern Australia supports the world’s largest estate of undeveloped tropical savannas, but previous studies of ant diversity in the region have covered only a fraction of its land area and habitat diversity. We assess patterns of ant species and functional diversity, their environmental predictors, and biogeographic significance in the central North Kimberley region of Australia’s seasonal tropics. Pitfall traps were used to sample ants at 69 plots in representative savanna habitats, collecting a total of 158 species from 30 genera. Total richness was estimated to be as high as 237 species. At least 29 species across 12 genera appear to have been collected for the first time. Only a single invasive ant was recorded from the study area. Based on cluster analysis we identified six compositionally distinct ant communities, each associated with a combination of vegetation type and underlying geology. Species richness and functional diversity was highest in savanna woodlands and grasslands on sandstone-derived soils, with increasing richness also predicted by a lower mean daily temperature range, a more complex understorey, and lower precipitation seasonality. The abundance of nearly all commonly trapped species was related to temperature, moisture, and habitat variables, although these relationships were highly idiosyncratic. Nearly 40 % of the collected species are known only from the North Kimberley region. The high level of endemism, together with the lack of introduced ant species, identifies the North Kimberley ant fauna as having outstanding biodiversity value. Our identification of ant community types based on mappable soil and vegetation units provides a basis for predicting ant distribution throughout the broader region, and therefore contributing to regional conservation planning and management

Hookworm Infection in Oceania

Hookworm disease and its associated morbidities continue to be a major public health problem in many tropical and subtropical nations and remain endemic throughout the Oceania region. Three species of hookworm cause patent infection in humans in this region: Necator americanus, Ancylostoma duodenale and Ancylostoma ceylanicum. Historical hookworm infection rates of up to 90 % throughout many parts of Oceania have significantly declined; however, the disease remains a major problem requiring ongoing public health intervention. The effectiveness of such interventions is evident in northern Australia, where once widespread hookworm disease is now limited to a few remaining endemic foci of isolated communities in the far north of the country. Outside of Australia, there is limited data available in the literature on hookworm prevalence, but a few recent (since 2000) studies have found hookworm prevalence rates of between 3 and 23 %. Infections with A. caninum, leading to eosinophilic enteritis, and sporadic cases cutaneous larva migrans caused by dermal migration of animal hookworm larva are also reported from several regions. This chapter provides a comprehensive review of both the historical and current literature on species of hookworms infecting humans and the geographical prevalence and distribution of hookworm disease in the Oceania region