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Abstract Background Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub-Saharan Africa. The Efé pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. Method Volunteer participants ( N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The χ2-test and Fisher's exact test were used for the comparison of proportions and the Student's t-test to compare means. The association between age group and anti-EBOV IgG prevalence was analysed by a nonparametric test for trend. Results The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age ( p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). Conclusions The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies.

The eastern pygmy-possum (Cercartetus nanus) occurs broadly but patchily in south-eastern Australia. It is a small, difficult-to-trap marsupial with poorly known resource and habitat preferences. This study investigated the structural and floristic habitat resources used and selected by C. nanus in Royal National Park (which was heavily burnt by bushfire in 1994) and Heathcote National Park (most of which had remained unburnt for over two decades at the time of study), in central-coastal New South Wales. Three different sampling methods were used – pitfall traps, Elliott traps and hair tubes – with pitfall trapping being by far the most effective method for detecting C. nanus. Live-trapping in different habitats revealed higher numbers of C. nanus in unburnt and burnt woodland, burnt heathland and burnt coastal complex than in unburnt coastal complex and burnt and unburnt rainforest. To identify the components of habitat contributing to this pattern, we first scored floristic and structural features of vegetation around trap stations and then quantified habitat components further by using spool- and radio-tracking. We found little evidence that C. nanus responded to any structural components of habitat, although arboreal activity was greater, not surprisingly, in wooded than in burnt heathland habitats. C. nanus was associated most strongly with the abundance of certain plants in the Proteaceae and Myrtaceae. In particular, the species prefers Banksia spp. (probably for food) and Eucalyptus and Xanthorrhoea spp. (probably for shelter).

Background Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub- Saharan Africa. The Efé pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. Method Volunteer participants (N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The χ2-test and Fisher's exact test were used for the comparison of proportions and the Student's t-test to compare means. The association between age group and anti- EBOV IgG prevalence was analysed by a nonparametric test for trend. Results The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age (p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). Conclusions The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies.

Pediculus humanus is an obligate bloodsucking parasite of humans that has two ecotypes, the head louse and the body louse, which share an intimate history of coevolution with their human host. In the present work, we obtained and analysed head and body lice collected from Mbuti pygmies living in the Orientale province of the Democratic Republic of the Congo. Cytochrome b DNA analysis was performed in order to type the six known lice clades (A, D, B, F, C and E). The results revealed the presence of two mitochondrial clades. Clade D was the most frequent (61.7% of 47), followed by clade A (38.3% of 47). Sixteen haplotypes were found in 47 samples, of which thirteen were novel haplotypes, indicating an unusually high genetic diversity that closely mirrors the diversity of their hosts. Moreover, we report for the first time the presence of the DNA of R. felis in three (6.4% of 47) head and body lice belonging to both clades A and D. Additional studies are needed to clarify whether the Pediculus lice can indeed transmit this emerging zoonotic bacterium to their human hosts.

14 p. ; Pond physical characteristics (connectivity, hydroperiod) have shown to be highly relevant in explaining species presence, reproductive success, and survival in breeding-pond amphibians. However, few studies have addressed the influence that these factors may have on the genetic variability of pond populations. We examined genetic variation at 11 microsatellite loci in Iberian endemic, the pygmy newt (Triturus pygmaeus), from 58 breeding ponds in the Doñana National Park (Andalusia), including both temporary ponds and artificially deepened ponds that remain wet during the whole year. Temporary ponds are located in the North part of the region where the surrounding habitat-wet meadows-facilitates the connectivity among populations, whereas the deepest ponds ('zacallones') are located in the southern edge embedded in a matrix of unsuitable habitat (thickets and dry underbrush). We investigated genetic diversity and structure within and among ponds. Our results show that both regions (Doñana-North and Doñana-South) are well-differentiated and form two main clusters. We found higher genetic diversity within ponds from the North region, which also exhibited a higher degree of genetic admixture in comparison with populations from the southern edge. Although we found an isolation-by-distance pattern within each cluster, it arose due to the effect of a few isolated ponds located on the edge of each zone, suggesting the existence of substantial gene flow between ponds in the core area. According to our findings, landscape's permeability to movement (pond connectivity) may constitute a more important factor than hydroperiod length in determining the genetic diversity and viability of pygmy newt populations in this area. Although Doñana populations show a good state, more peripheral and isolated populations present a more worrisome condition as a result of fragmentation and thus, require conservation efforts. Our study provides key insights that could help guide management practices of this threatened and poorly-studied salamander. ; Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was funded by the grants of the Government of Andalusia (Consejería de Economía, Innovación y Ciencia) through the projects P07-RNM-02928 and RNM8147. V. García-Navas was supported by a "Ramón y Cajal" contract (ref. RYC2019-026703-I) from the Spanish Ministry of Science and Innovation. ; Peer reviewed

Context Selective logging of native forests creates a mosaic of disturbance histories; however, little is known about how different taxa respond to such a mosaic. Aims We followed adaptive-management principles to test logging and burning impacts on eastern pygmy possums, Cercartetus nanus (Geoffroy and Desmarest, 1817), by undertaking a large-scale field experiment that coincided with harvesting. We predicted that home range would increase after logging because of a reduction in resources (food and/or dens) and because hollows suitable for denning would decrease, resulting in greater use of unlogged patches and alternate dens. Methods We radio-tracked C. nanus in a before-and-after logging experiment to investigate home range, habitat selection and den use. We tracked 50 possums, some individuals for a maximum of 8 months, within control, recently logged and regrowth (5 years since logging) sites. Key results Home ranges were variable (0.04–19.5 ha), with males having significantly larger home ranges. We were unable to detect a difference in home-range size between controls and the first year after logging and burning, or regrowth 5 years after logging. Home ranges comprised a mosaic of disturbed and undisturbed areas, and possums did not avoid logged habitat in their home ranges, indicating that logging did not significantly influence habitat selection. We suggest that possums were not sensitive to selective logging and burning because nectar-producing plants are adapted to fire disturbance and because a variety of den sites were used, most commonly in tree hollows and fallen logs, which were commonly left as logging residue. Indeed, possums frequently denned in logged patches, both recently after logging (63% of dens) and in regrowth 5 years after logging (76% of dens). Counts of fallen hollow logs at each site indicated that their density was not reduced by logging, with regrowth sites having the greatest abundance of logs (260 ha–1). Conclusions The mosaic of disturbance created by selective logging operations did not negatively affect home range or den selection of C. nanus. Implications Ecologically sustainable logging practices that include a range of mitigation measures to protect biodiversity can be compatible with the management of threatened species. Assessment of the effectiveness of these methods often will rely on scientific research.

Context Many ectothermic animals survive winter by hibernating, either buried or in burrows. During their hibernation these animals are vulnerable to changes in soil structure and temperature caused by the activity of grazing mammals. This may be a particular risk to ectotherms living in native grassland, as this habitat is often used for livestock grazing. The endangered pygmy bluetongue lizard lives in burrows, in fragments of native grassland in South Australia, and these burrows are likely to be affected by sheep grazing during the lizards' hibernation. Aims The current study aimed to determine the following effects on the persistence of burrows suitable to the pygmy bluetongue lizard: different levels of grazing, winter vegetation cover, burrow entrance size and whether a lizard was overwintering in the burrow. Methods During two winters, we applied different grazing treatments to six experimental paddocks and determined whether suitable lizard burrows located in autumn were still suitable to lizards in the following spring. For each burrow, we recorded whether a lizard was overwintering, the burrow entrance diameter and the vegetation cover around the burrow during the winter. Key results Increased grazing pressure led to decreased persistence of lizard burrows. We also found that burrows with an overwintering lizard had a greater chance of persisting, but found no direct effect of winter vegetation cover or entrance diameter. Conclusions The results show that although pygmy bluetongue lizards may be able to stabilise their own burrows, the more intense the grazing the lower the chance of lizard burrow persistence. Implications Management of sheep grazing is an important component in future conservation of the endangered pygmy bluetongue lizard. Grazing on grassland with a lizard population should be kept at a moderate level and hard grazing should be avoided.

BACKGROUND : Factors related to the natural transmission of Ebola virus (EBOV) to humans are still not well defined. Results of previous sero-prevalence studies suggest that circulation of EBOV in human population is common in sub-Saharan Africa. The Efé pygmies living in Democratic Republic of the Congo are known to be exposed to potential risk factors of EBOV infection such as bush meat hunting, entry into caves, and contact with bats. We studied the pygmy population of Watsa region to determine seroprevalence to EBOV infection and possible risks factors. METHOD : Volunteer participants (N = 300) aged 10 years or above were interviewed about behavior that may constitute risk factors for transmission of EBOV, including exposures to rats, bats, monkeys and entry into caves. Samples of venous blood were collected and tested for IgG antibody against EBOV by enzyme-linked immunosorbent assay (ELISA). The χ2-test and Fisher's exact test were used for the comparison of proportions and the Student's t-test to compare means. The association between age group and anti-EBOV IgG prevalence was analysed by a nonparametric test for trend. RESULTS : The prevalence of anti-EBOV IgG was 18.7 % overall and increased significantly with age (p = 0.023). No association was observed with exposure to risk factors (contacts with rats, bats, monkeys, or entry into caves). CONCLUSIONS : The seroprevalence of IgG antibody to EBOV in pygmies in Watsa region is among the highest ever reported, but it remains unclear which exposures might lead to this high infection rate calling for further ecological and behavioural studies. ; Additional file 1: Efe pygmy, Watsa, DRC: EBOV exposures data. ; 'Fonds voor Wetenschappelijk Onderzoek—Vlaanderen' [1.5.188.01], Antwerp; the Framework Agreement between the Belgian Directorate for Development Co-operation and the Institute of Tropical Medicine, Antwerp and the Wellcome Trust Grant [WT087546MA] to the Southern African Centre for Infectious Diseases and Surveillance (SACIDS). ...

Context Climate change is causing changes to seasonal food resources, with critical health and survival impacts for many species. The endangered Burramys parvus (mountain pygmy-possum) predominantly consumes Agrotis infusa (Bogong moth), a long-distance seasonal migrant. Aims We aimed to examine direct and indirect climate-related influences on B. parvus food resources so as to assess the susceptibility of the species to climate change. Methods We analysed a long-term (17-year) data record of B. parvus faecal samples from sites across a climate gradient, in relation to plant-growth indices derived from climate data. We also modelled the population dynamics of A. infusa against climate variables and in relation to the probability of consumption by B. parvus. Key Results The diet of B. parvus was highly variable among sites and years and there were strong seasonal patterns for predominant food resources (A. infusa, other local arthropods, Podocarpus sp. and other local seeds). Seasonal patterns generally diminished with an increasing elevation, which may be due to resource availability or complex interactions with food preferences. Growth conditions across spatially far removed A. infusa breeding grounds influenced their abundance recorded in the Alps in spring, which was reflected in B. parvus diet. Conclusions Strong seasonal and climatic influences on dominant food resources suggest that B. parvus may be susceptible to climate change. Selective foraging for the lipid-rich A. infusa and Podocarpus sp. seed suggests that there may be important health and survival benefits for B. parvus. Implications Given the dependence on cooler, higher-elevation aestivation sites, A. infusa may have reduced survival in a warmer world. Climate change across the vast migratory route of A. infusa is likely to further affect survival and availability for consumption by B. parvus. Predicted increases in fire frequency and severity may reduce availability of the fire-sensitive Podocarpus sp. The health and survival of B. parvus may be compromised as a result of reduced availability of A. infusa and Podocarpus seed and a greater dependence on angiosperm plants (seeds and nectar) and local arthropods because of the consequent change in dietary lipid composition. Integrated predictive modelling of A. infusa and B. parvus population dynamics under future climate-change scenarios is recommended.

Context
Grazing by domestic stock can potentially influence ecosystems positively or negatively, depending on the grazing regime and intensity. The pygmy bluetongue lizard (Tiliqua adelaidensis) is an endangered species, restricted to fragmented grasslands in the Mid North region of South Australia, predominantly grazed by sheep. These lizards refuge in vertical burrows. They do not dig their own burrows, instead relying on co-existing spiders for this essential resource.

Aims
We investigated how sheep grazing influenced spider burrows, and predicted the following: that grazing sheep might trample and destroy shallow burrows; that burrows in grazed habitat with less vegetative cover would have higher temperatures in summer; and that, by way of compensation, spiders would dig deeper burrows in grazed habitat.

Methods
We monitored 12 30m×30m plots monthly, over two austral spring/summer periods (September–March 2012–14). We recorded the number, depth and occupant of all spider burrows in those plots in each survey. We also measured temperatures inside artificial burrows in grazed and ungrazed habitat over a 3-day period in September 2014.

Key results
Mean burrow depth increased with grazing. This was not because individual burrows became deeper, but because the shallowest burrows were lost where there were sheep. Burrows were significantly hotter in grazed habitat, but lizards consistently chose deeper, cooler burrows. In the subset of burrows that were occupied by lizards, there was no difference in depth between grazed and ungrazed treatments. We detected no difference in spider digging activity between grazed and ungrazed plots.

Conclusions
Sheep grazing can destroy shallow burrows, probably through trampling, and because sheep produce burrow filling debris. However, grazing did not affect deeper burrows occupied by pygmy bluetongue lizards.

Implications
This short study indicated that moderate levels of grazing have low impact on deeper burrows suitable for pygmy bluetongue lizards and for lizard persistence. It explains how sheep and lizards have co-occurred for so long, but leaves open the question of how the loss of shallow burrows affects populations of the burrow-digging spiders that are an essential component of the lizard environment.