Experimental evaluation of koala scat persistence and detectability with implications for pellet-based fauna census

Establishing species distribution and population trends are basic requirements in conservation biology, yet acquiring this fundamental information is often difficult. Indirect survey methods that rely on fecal pellets (scats) can overcome some difficulties but present their own challenges. In particular, variation in scat detectability and decay rate can introduce biases. We studied how vegetation communities affect the detectability and decay rate of scats as exemplified by koalas Phascolarctos cinereus: scat detectability was highly and consistently dependent on ground layer complexity (introducing up to 16% non-detection bias); scat decay rates were highly heterogeneous within vegetation communities; exposure of scats to surface water and rain strongly accelerated scat decay rate and finally, invertebrates were found to accelerate scat decay rate markedly, but unpredictably. This last phenomenon may explain the high variability of scat decay rate within a single vegetation community. Methods to decrease biases should be evaluated when planning scat surveys, as the most appropriate method(s) will vary depending on species, scale of survey and landscape characteristics. Detectability and decay biases are both stronger in certain vegetation communities, thus their combined effect is likely to introduce substantial errors in scat surveys and this could result in inappropriate and counterproductive management decisions

Removing krypton from xenon by cryogenic distillation to the ppq level

The XENON1T experiment aims for the direct detection of dark matter in a cryostat filled with 3.3 tons of liquid xenon. In order to achieve the desired sensitivity, the background induced by radioactive decays inside the detector has to be sufficiently low. One major contributor is the $\beta$-emitter $^{85}$Kr which is an intrinsic contamination of the xenon. For the XENON1T experiment a concentration of natural krypton in xenon $\rm{^{nat}}$Kr/Xe < 200 ppq (parts per quadrillion, 1 ppq = 10$^{-15}$ mol/mol) is required. In this work, the design of a novel cryogenic distillation column using the common McCabe-Thiele approach is described. The system demonstrated a krypton reduction factor of 6.4$\cdot$10$^5$ with thermodynamic stability at process speeds above 3 kg/h. The resulting concentration of $\rm{^{nat}}$Kr/Xe < 26 ppq is the lowest ever achieved, almost one order of magnitude below the requirements for XENON1T and even sufficient for future dark matter experiments using liquid xenon, such as XENONnT and DARWIN

Aging cheetahs using gum‐line recession and evaluation of expert‐based aging techniques

Accurate aging is a useful tool in wildlife management, providing critical information for population dynamics research, age‐specific limiting factors, and conservation efforts. Many methods used to age mammalian carnivores are either invasive, expensive, or inconvenient to use in the field. In felids, the gum‐line recession has been found to accurately estimate the age of female mountain lions and tigers. In contrast, expert‐based aging techniques used on cheetahs (Acinonyx jubatus) can only categorize adults into broad age classes. We assessed whether the gum‐line recession of the upper canine teeth provides reliable information for aging cheetahs by using measurements on cheetahs of known age (n = 37) in sex‐specific linear models. We found a significant positive relationship between gum‐line recession and known age for both female (n = 21) and male cheetahs (n = 16), and we contribute herein sex‐specific regression models that can be used to age the animals based on the gum‐line measurements collected during handling. In addition, we compared expert‐derived age categories assigned to cheetahs of unknown age (n = 23) to the ages estimated by the gum‐line recession models. Expert‐based aging produced similar results to gum‐line recession for some individuals, but the ages of other individuals were underestimated by biologists, particularly for older cheetahs. Our data show that gum‐line recession measurements provide biologists with a reliable, minimally invasive, and convenient technique to age cheetahs in the field, and we encourage validation of this technique in other field‐intensive projects involving felid capture

Leopards living at the farmland‐protected area interface prefer wild prey but consume high biomass of livestock

In much of southern Africa, the leopard (Panthera pardus) is the last remaining large carnivore outside protected areas. We collected leopard scat (n = 82) opportunistically to determine the diet of leopards on small livestock farms and an adjacent national park in semi-arid Namaqualand, South Africa. We quantified prey availability using camera traps (n = 163 stations) in an 810 km2 grid. Leopards strongly preferred (D &gt; 0.5) rock hyrax (Procavia capensis), red hartebeest (Alcelaphus buselaphus) and klipspringer (Oreotragus oreotragus), but goats (Capra hircus) were consumed in highest biomass. Conservation strategies to decrease livestock losses and minimise leopard persecution are needed in Namaqualand and more broadly on livestock farmland neighbouring-protected areas

Diet and Environment Shape Fecal Bacterial Microbiota Composition and Enteric Pathogen Load of Grizzly Bears

Background: Diet and environment impact the composition of mammalian intestinal microbiota; dietary or health disturbances trigger alterations in intestinal microbiota composition and render the host susceptible to enteric pathogens. To date no long term monitoring data exist on the fecal microbiota and pathogen load of carnivores either in natural environments or in captivity. This study investigates fecal microbiota composition and the presence of pathogenic Escherichia coli and toxigenic clostridia in wild and captive grizzly bears (Ursus arctos) and relates these to food resources consumed by bears. Methodology/Principal Findings: Feces were obtained from animals of two wild populations and from two captive animals during an active bear season. Wild animals consumed a diverse diet composed of plant material, animal prey and insects. Captive animals were fed a regular granulated diet with a supplement of fruits and vegetables. Bacterial populations were analyzed using quantitative PCR. Fecal microbiota composition fluctuated in wild and in captive animals. The abundance of Clostridium clusters I and XI, and of C. perfringens correlated to regular diet protein intake. Enteroaggregative E. coli were consistently present in all populations. The C. sordellii phospholipase C was identified in three samples of wild animals and for the first time in Ursids. Conclusion: This is the first longitudinal study monitoring the fecal microbiota of wild carnivores and comparing it to that o

ANALYSIS OF LIFE INSURANCE INVESTMENT COMPOSITION

Economic recession and global mettle down have brought the question of insurance company investment to the forefront. Growing attention has shifted to the pattern of investments by the insurance and question of how to evaluate such investments. The aim of this research is to evaluate investment compositions which are made by life insurance companies in Indonesia, as well as to know the effects on the performance of Insurance companies

A first AFLP-based genetic linkage map for brine shrimp Artemia franciscana and its application in mapping the sex locus

We report on the construction of sex-specific linkage maps, the identification of sex-linked markers and the genome size estimation for the brine shrimp Artemia franciscana. Overall, from the analysis of 433 AFLP markers segregating in a 112 full-sib family we identified 21 male and 22 female linkage groups (2n = 42), covering 1,041 and 1,313 cM respectively. Fifteen putatively homologous linkage groups, including the sex linkage groups, were identified between the female and male linkage map. Eight sex-linked AFLP marker alleles were inherited from the female parent, supporting the hypothesis of a WZ-ZZ sex-determining system. The haploid Artemia genome size was estimated to 0.93 Gb by flow cytometry. The produced Artemia linkage maps provide the basis for further fine mapping and exploring of the sex-determining region and are a possible marker resource for mapping genomic loci underlying phenotypic differences among Artemia species