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We propose an improved comprehensive method for determining the Hubble constant (⁠|$H_0$|⁠) using the Tully–Fisher relation. By fitting a peculiar velocity model in conjunction with the Tully–Fisher relation, all available data can be used to derive self-consistent Tully–Fisher parameters. In comparison to previous approaches, our method offers several improvements: it can be readily generalized to different forms of the Tully–Fisher relation and its intrinsic scatter; it uses a peculiar velocity model to predict distances more accurately; it can account for all selection effects; it uses the entire data set to fit the Tully–Fisher relation; and it is fully self-consistent. The Tully–Fisher relation zero-point is calibrated using the subset of galaxies with distances from absolute distance indicators. We demonstrate this method on the Cosmicflows-4 catalogue i -band and |$W1$| -band Tully–Fisher samples and show that the uncertainties from fitting the Tully–Fisher relation amount to only 0.2 km s |$^{-1}$|  Mpc |$^{-1}$|⁠. Using all available absolute distance calibrators, we obtain |$H_0=73.3$|   |$\pm$|  2.1 (stat)  |$\pm$|  3.5 (sys) km s |$^{-1}$|  Mpc |$^{-1}$|⁠ , where the statistical uncertainty is dominated by the small number of galaxies with absolute distance estimates. The substantial systematic uncertainty reflects inconsistencies between various zero-point calibrations of the Cepheid period–luminosity relation, the tip of the red giant branch standard candle, and the Type Ia supernova standard candle. However, given a reliable set of absolute distance calibrators, our method promises enhanced precision in |$H_0$| measurements from large new Tully–Fisher samples such as the WALLABY survey. [ABSTRACT FROM AUTHOR]

We propose an improved comprehensive method for determining the Hubble constant (⁠|$H_0$|⁠) using the Tully–Fisher relation. By fitting a peculiar velocity model in conjunction with the Tully–Fisher relation, all available data can be used to derive self-consistent Tully–Fisher parameters. In comparison to previous approaches, our method offers several improvements: it can be readily generalized to different forms of the Tully–Fisher relation and its intrinsic scatter; it uses a peculiar velocity model to predict distances more accurately; it can account for all selection effects; it uses the entire data set to fit the Tully–Fisher relation; and it is fully self-consistent. The Tully–Fisher relation zero-point is calibrated using the subset of galaxies with distances from absolute distance indicators. We demonstrate this method on the Cosmicflows-4 catalogue i -band and |$W1$| -band Tully–Fisher samples and show that the uncertainties from fitting the Tully–Fisher relation amount to only 0.2 km s |$^{-1}$|  Mpc |$^{-1}$|⁠. Using all available absolute distance calibrators, we obtain |$H_0=73.3$|   |$\pm$|  2.1 (stat)  |$\pm$|  3.5 (sys) km s |$^{-1}$|  Mpc |$^{-1}$|⁠ , where the statistical uncertainty is dominated by the small number of galaxies with absolute distance estimates. The substantial systematic uncertainty reflects inconsistencies between various zero-point calibrations of the Cepheid period–luminosity relation, the tip of the red giant branch standard candle, and the Type Ia supernova standard candle. However, given a reliable set of absolute distance calibrators, our method promises enhanced precision in |$H_0$| measurements from large new Tully–Fisher samples such as the WALLABY survey. [ABSTRACT FROM AUTHOR]

The Tully–Fisher Relation (TFR) is a well-known empirical relationship between the luminosity of a spiral galaxy and its circular velocity, allowing us to estimate redshift independent distances. Here we use high signal-to-noise H  i 21-cm integrated spectra from the second pilot data release (PDR2, 180 deg2) of the Widefield ASKAP L -band Legacy All-sky Blind surveY (WALLABY). In order to prepare for the full WALLABY survey, we have investigated the TFR in phase 2 of the pilot survey with a further three fields. The data were obtained with wide-field Phased Array Feeds on the Australian Square Kilometre Array Pathfinder (ASKAP) and have an angular resolution of 30 arcsec and a velocity resolution of |$\sim$| 4 km s−1. Galaxy luminosities have been measured from the Wide-field Infrared Survey Explorer , and optical galaxy inclinations from the Dark Energy Camera Legacy Survey. We present TFRs for wavelengths from 0.8 to 3.4  μ m. We examine sources of galaxy inclination data and investigate magnitudes from the DECam Local Volume Exploration Survey and DENIS catalogues and the 4HS target catalogue based on the VISTA Hemisphere Survey. We consider the baryonic TFR. These are all of interest for TFR using the full WALLABY survey of 200 000 galaxies. We demonstrate that WALLABY TFR distances can take their place among state-of-the-art studies of the local velocity field. [ABSTRACT FROM AUTHOR]

Background: We studied the occurrence of two sympatric wallabies, the red-necked pademelon (Thylogale thetis) and the red-legged pademelon (T. stigmatica) in northeastern New South Wales, Australia in relation to structural habitat attributes. At our study site, both species inhabit closed forest environments and have overlapping distributions, but T. thetis leaves the forest at night to graze adjacent grassy forest edges whereas T. stigmatica remains within the forest and browses forest vegetation. The objectives of the study were to investigate how structural attributes of two forest types, wet sclerophyll forest and rainforest, relate to the fine-scale occurrence of these two wallaby species within the forested environment. Methods: We gathered occurrence data from 48 camera trap stations divided equally between rainforest and wet sclerophyll forest. At each camera point, we also measured a range of structural habitat attributes to determine habitat affiliations for the two Thylogale species. Principal component analyses were used to describe major trends in habitat, and generalised linear models were used to describe the efficacy of the variables in predicting habitat occurrence of each species. Results: The number of occurrences of Thylogale thetis was significantly greater than occurrences of T. stigmatica, which was driven by significantly greater occurrences of T. thetis in wet sclerophyll forest. There was both spatial and temporal partitioning between the two species; there was a significant difference in the occurrences of the two species at individual cameras and T. stigmatica had a different activity schedule than T. thetis in wet sclerophyll forest, where the latter reached its greatest rate of occurrence. At a finer (camera station) scale, occurrences of T. thetis increased with proximity to roads and grassy edges and at sites that were less rocky and less steep. T. stigmatica occurrence increased in the presence of rainforest elements like vines, palms and ferns, more ground-level cover and tree-fall gaps and at sites with fewer emergent eucalypts. Conclusion: Our findings have implications for managing these pademelons and their habitats. T. thetis is a common species that was encountered more often than T. stigmatica, and it responded positively to human disturbance like roadsides and grassy edges, presumably because these areas provided good grazing opportunities. By comparison, T. stigmatica is a threatened species, and it responded to natural disturbance like tree-fall gaps where lateral cover was greater, and where rainforest food plants may be more abundant. Our results suggest, therefore, that conservation of the threatened T. stigmatica requires the preservation of intact rainforest. [ABSTRACT FROM AUTHOR]

Camera-trapping programs are most effective when informed by knowledge of the influence of components of the camera setup such as bait and camera type. I investigated the influence of two baits and three camera types on detection of eight species of medium-sized mammals across a 10-month survey. The spotted-tailed quoll (Dasyurus maculatus) was the only species that favoured a meat bait (sardines) over a peanut-butter bait. The long-nosed potoroo (Potorous tridactylus), Parma wallaby (Notamacropus parma), long-nosed bandicoot (Perameles nasuta) and swamp wallaby (Wallabia bicolor) favoured the peanut-butter bait over the meat bait. The northern brown bandicoot (Isoodon macrourus), mountain brushtail possum (Trichosurus caninus) and feral cat (Felis catus) showed no preference. Camera type influenced weekly detection in three species. The long-nosed bandicoot had lower detection at a Reconyx white-flash (WF) camera compared with a Reconyx infra-red flash (IR) and a Swift wide-angle (Sw) camera. The mountain brushtail possum had higher detection at a Sw compared with WF and IR. The feral cat had higher detection at a WF compared with IR and Sw. The findings have implications in relation to selection of bait and camera type that can lead to more effective monitoring, whether a program is directed at one of these species or the spectrum of species. Camera-trapping programs need to be informed by decisions made around bait and camera type, as well as camera deployment and service intervals. This study investigated these factors in relation to the detection of eight medium-sized mammal species, including three threatened species: the spotted-tailed quoll; long-nosed potoroo; and Parma wallaby. Photograph by R. Goldingay. [ABSTRACT FROM AUTHOR]

We explore the properties of an 'almost' dark cloud of neutral hydrogen (H  i) using data from the Widefield ASKAP L-band Legacy All-sky Survey (WALLABY). Until recently, WALLABY J103508 − 283427 (also known as H1032 − 2819 or LEDA 2793457) was not known to have an optical counterpart, but we have identified an extremely faint optical counterpart in the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Survey Data Release 10. We measured the mean g -band surface brightness to be 27.0 ± 0.3 mag arcsec−2. The WALLABY data revealed the cloud to be closely associated with the interacting group Klemola 13 (also known as HIPASS J1034 − 28 and the Tol 9 group), which itself is associated with the Hydra cluster. In addition to WALLABY J103508 − 283427/H1032 − 2819, Klemola 13 contains 10 known significant galaxies and almost half of the total H  i gas is beyond the optical limits of the galaxies. By combining the new WALLABY data with archival data from the Australia Telescope Compact Array, we investigate the H  i distribution and kinematics of the system. We discuss the relative role of tidal interactions and ram pressure stripping in the formation of the cloud and the evolution of the system. The ease of detection of this cloud and intragroup gas is due to the sensitivity, resolution, and wide field of view of WALLABY, and showcases the potential of the full WALLABY survey to detect many more examples. [ABSTRACT FROM AUTHOR]

The agile wallaby (Notamacropus agilis) is one of the most abundant marsupial species in northern Queensland and a competent host for the zoonotic Ross River virus. Despite their increased proximity and interactions with humans, little is known about the viruses carried by these animals, and whether any are of conservation or zoonotic importance. Metagenomics and molecular techniques were used in a complementary manner to identify and characterize novel viruses in the fecal samples of free-ranging agile wallabies. We detected a variety of novel marsupial-related viral species including agile wallaby atadenovirus 1, agile wallaby chaphamaparvovirus 1–2, agile wallaby polyomavirus 1–2, agile wallaby associated picobirnavirus 1–9, and a known macropod gammaherpesvirus 3. Phylogenetic analyses indicate that most of these novel viruses would have co-evolved with their hosts (agile wallabies). Additionally, non-marsupial viruses that infect bacteria (phages), plants, insects, and other eukaryotes were identified. This study highlighted the utility of non-invasive sampling as well as the integration of broad-based molecular assays (consensus PCR and next generation sequencing) for monitoring the emergence of potential pathogenic viruses in wildlife species. Furthermore, the novel marsupial viruses identified in this study will enrich the diversity of knowledge about marsupial viruses, and may be useful for developing diagnostics and vaccines. [ABSTRACT FROM AUTHOR]

We report on the discovery of two potential polar ring galaxies (PRGs) in the WALLABY Pilot Data Release 1 (PDR1). These untargeted detections, cross-matched to NGC 4632 and NGC 6156, are some of the first galaxies where the H  i observations show two distinct components. We used the iDaVIE virtual reality software to separate the anomalous gas from the galactic gas and found that the anomalous gas comprises ∼50 per cent of the total H  i content of both systems. We have generated plausible 3D kinematic models for each galaxy, assuming that the rings are circular and inclined at 90° to the galaxy bodies. These models show that the data are consistent with PRGs but do not definitively prove that the galaxies are PRGs. By projecting these models at different combinations of main disc inclinations, ring orientations, and angular resolutions in mock data cubes, we have further investigated the detectability of similar PRGs in WALLABY. Assuming that these galaxies are indeed PRGs, the detectability fraction, combined with the size distribution of WALLABY PDR1 galaxies, implies an incidence rate of ∼1–3 per cent. If this rate holds true, the WALLABY survey will detect hundreds of new polar ring galaxies. [ABSTRACT FROM AUTHOR]

Extracellular recordings were made from 642 units in the primary visual cortex (V1) of a highly visual marsupial, the Tammar wallaby. The receptive field (RF) characteristics of the cells were objectively estimated using the non-linear input model (NIM), and these were correlated with spike shapes. We found that wallaby cortical units had 68% regular spiking (RS), 12% fast spiking (FS), 4% triphasic spiking (TS), 5% compound spiking (CS) and 11% positive spiking (PS). RS waveforms are most often associated with recordings from pyramidal or spiny stellate cell bodies, suggesting that recordings from these cell types dominate in the wallaby cortex. In wallaby, 70-80% of FS and RS cells had orientation selective RFs and had evenly distributed linear and nonlinear RFs. We found that 47% of wallaby PS units were non-orientation selective and they were dominated by linear RFs. Previous studies suggest that the PS units represent recordings from the axon terminals of non-orientation selective cells originating in the lateral geniculate nucleus (LGN). If this is also true in wallaby, as strongly suggested by their low response latencies and bursty spiking properties, the results suggest that significantly more neurons in wallaby LGN are already orientation selective. In wallaby, less than 10% of recorded spikes had triphasic (TS) or sluggish compound spiking (CS) waveforms. These units had a mixture of orientation selective and non-oriented properties, and their cellular origins remain difficult to classify. [ABSTRACT FROM AUTHOR]

When foraging, making appropriate food choices is crucial to an animal's fitness. Classic foraging ecology theories assume animals choose food of greatest benefit based on their absolute value across multiple dimensions. Consequently, poorer options are considered irrelevant alternatives that should not influence decision-making among better options. But heuristic studies demonstrate that irrelevant alternatives (termed decoys) can influence the decisions of some animals, indicating they use a relative rather than absolute evaluation system. Our aim was to test whether a decoy influenced the decision-making process—that is, information-gathering and food choice—of a free-ranging mammalian herbivore. We tested swamp wallabies, Wallabia bicolor, comparing their behavior toward, and choice of, two available food options over time in the absence or presence of the decoy. We used a phantom decoy—unavailable option—and ran two trials in different locations and seasons. Binary preferences (decoy absent) for the two available food options differed between trials. Irrespective of this difference, across both trials the presence of the decoy resulted in animals more likely to overtly investigate available food options. But, the decoy only shifted food choice, weakly, in one trial. Our results indicate that the decoy influenced the information-gathering behavior during decision-making, providing the first evidence that decoys can affect decision-making process of free-ranging mammalian herbivores in an ecologically realistic context. It is premature to say these findings confirm the use of relative evaluation systems. Whether the foraging outcome is more strongly affected by other decoys, food dimensions, or ecological contexts, is yet to be determined. [ABSTRACT FROM AUTHOR]

Urban development is thought to negatively affect most native mammals. Here we assess whether adjacent suburbia, fire regime and vegetation influence the activity of mammal species in a reserve in Hobart, Tasmania, Australia. We used multiple regression to analyse the relationship between distance from houses, fire history, vegetation structure and floristics, and mammal activity, derived from camera visits and signs. Animal diggings and visits by long-nosed potoroos, southern brown bandicoots and cats were greater close to houses, while visits by red-necked wallabies, rufous-bellied pademelons, brushtail possums and short-beaked echidnas were not. The structure of the vegetation, particularly related to shelter, was important in many models. Many models also included floristic ordination axes that reflected drainage, fire regime and distance from high-density housing. Positive relationships between the introduced predatory cat and some of its potential native prey animals may reflect the influences of close proximity to suburbia, such as elevated domestic mesopredator populations, and elevated resource availability in domestic gardens. Our results suggest that urban areas can have a valuable role in nature conservation, despite, or because of, their effects on remnant native ecosystems. [ABSTRACT FROM AUTHOR]

The homologies of the turbinals (scroll bones) of the ethmoid are not well understood, including the potential implication for understanding mammalian phylogeny. Here we examine the postnatal development of this anatomical system in a marsupial mammal because previous work has shown that the adult pattern of five endoturbinals (ethmoturbinals) and two ectoturbinals (frontoturbinals) is conserved. Furthermore, marsupial phylogeny is fairly well resolved and provides a solid evolutionary framework for examining turbinal homologies. In this study, we documented the development of the ethmoid of the tammar wallaby, Notamacropus eugenii, using histology and computed tomography imagery of a growth series of pouch young. The pattern of development of the turbinal elements in the wallaby was compared to that in didelphids, as described in previous work. We found that four ethmoturbinals initially develop, followed later in development by an interturbinal; these five elements then develop into the bony endoturbinals found in adults. These data support the idea that endoturbinal III, derived from an interturbinal, has a distinctive development pattern from the other endoturbinals. This is consistent with what is seen in the didelphid marsupials, Caluromys philander and Monodelphis domestica, suggesting this is a common developmental pattern for marsupials. This article is part of the theme issue 'The mammalian skull: development, structure and function'. [ABSTRACT FROM AUTHOR]

In the mouse, the timing of meiosis onset differs between sexes due to the sex-specific regulation of the meiosis initiation factors, STRA8 and MEIOSIN. Before the initiation of meiotic prophase I, the Stra8 promoter loses suppressive histone-3-lysine-27 trimethylation (H3K27me3) in both sexes, suggesting that H3K27me3-associated chromatin remodelling may be responsible for activating STRA8 and its co-factor MEIOSIN. Here we examined MEIOSIN and STRA8 expression in a eutherian (the mouse), two marsupials (the grey short-tailed opossum and the tammar wallaby) and two monotremes (the platypus and the short-beaked echidna) to ask whether this pathway is conserved between all mammals. The conserved expression of both genes in all three mammalian groups and of MEIOSIN and STRA8 protein in therian mammals suggests that they are the meiosis initiation factors in all mammals. Analyses of published DNase-seq and chromatinimmunoprecipitation sequencing (ChIP-seq) data sets confirmed that H3K27me3-associated chromatin remodelling occurred at the STRA8, but not the MEIOSIN, promoter in therian mammals. Furthermore, culturing tammar ovaries with an inhibitor of H3K27me3 demethylation before meiotic prophase I affected STRA8 but not MEIOSIN transcriptional levels. Our data suggest that H3K27me3-associated chromatin remodelling is an ancestral mechanism that allows STRA8 expression in mammalian pre-meiotic germ cells. [ABSTRACT FROM AUTHOR]

Lead-based ammunition (gunshot and bullets) frequently leaves small lead fragments embedded in the meat of wild-shot game animals. Australia produces several commercial game meat products from wild animals harvested with lead-based ammunition and has a growing population of recreational hunters. However, no studies have previously investigated the frequency of lead fragments or lead concentrations in Australian game meat. We examined 133 Australian minced game meat items of four types for evidence of lead contamination. Samples were meat from kangaroos (Macropus and Osphranter spp.; n=36) and Bennett's wallabies (Notamacropus rufogriseus; n=28) sold for human consumption, and deer ('venison'; multiple spp.; n=32) and stubble quail (Coturnix pectoralis; n=37) harvested for private consumption by recreational hunters. All packages were studied by digital radiography to detect the presence of radio-dense fragments, assumed to be lead fragments from ammunition. Visible fragments were absent in commercially available kangaroo products, but were present in 4%, 28% and 35% of wallaby, venison and quail, respectively. Mean meat lead concentrations (mg/kg wet weight) were 0.01 ± 0.01 for kangaroo, 0.02 ± 0.01 for wallaby, 0.12 ± 0.07 for venison, and 1.76 ± 3.76 for quail. The Australian food standards threshold for livestock meat (0.1 mg/kg w.w.) was not exceeded by any kangaroo or wallaby products but was exceeded by 53% and 86% of venison and quail, respectively. Radiography only detected 35% of samples that were above the food safety threshold. While average lead concentrations in commercially available macropod (kangaroo and wallaby) meat were low, those in recreationally harvested game meat may pose health risks for hunters and associated consumers. [ABSTRACT FROM AUTHOR]

The WALLABY pilot survey has been conducted using the Australian SKA Pathfinder (ASKAP). The integrated 21-cm H  i line spectra are formed in a very different manner compared to usual single-dish spectra Tully–Fisher measurements. It is thus extremely important to ensure that slight differences (e.g. biases due to missing flux) are quantified and understood in order to maximise the use of the large amount of data becoming available soon. This article is based on four fields for which the data are scientifically interesting by themselves. The pilot data discussed here consist of 614 galaxy spectra at a rest wavelength of 21 cm. Of these spectra, 472 are of high enough quality to be used to potentially derive distances using the Tully–Fisher relation. We further restrict the sample to the 251 galaxies whose inclination is sufficiently close to edge-on. For these, we derive Tully–Fisher distances using the deprojected WALLABY velocity widths combined with infrared (WISE W 1) magnitudes. The resulting Tully–Fisher distances for the Eridanus, Hydra, Norma, and NGC4636 clusters are 21.5, 53.5, 69.4, and 23.0 Mpc, respectively, with uncertainties of 5–10 per cent, which are better or equivalent to the ones obtained in studies using data obtained with giant single dish telescopes. The pilot survey data show the benefits of WALLABY over previous giant single-dish telescope surveys. WALLABY is expected to detect around half a million galaxies with a mean redshift of |$z = 0.05 (200\, \mathrm{Mpc})$|⁠. This study suggests that about 200 000 Tully–Fisher distances might result from the survey. [ABSTRACT FROM AUTHOR]

We recently identified walbRep, a satellite DNA residing in the genome of the red‐necked wallaby Notamacropus rufogriseus. It originates from the walb endogenous retrovirus and is organized in a manner in which the provirus structure is retained. The walbRep repeat units feature an average pairwise nucleotide identity as high as 99.5%, raising the possibility of a recent origin. The tammar wallaby N. eugenii is a species estimated to have diverged from the red‐necked wallaby 2–3 million years ago. In PCR analyses of these two and other related species, walbRep‐specific fragment amplification was observed only in the red‐necked wallaby. Sequence database searches for the tammar wallaby resulted in sequence alignment lists that were sufficiently powerful to exclude the possibility of walbRep existence. These results suggested that the walbRep formation occurred in the red‐necked wallaby lineage after its divergence from the tammar wallaby lineage, thus in a time span of maximum 3 million years. [ABSTRACT FROM AUTHOR]

Summary: The rustrela virus (RusV) was recently described as a novel pathogen in a circumscribed area of northern Germany close to the Baltic Sea. Up to now, the virus has been detected in cases of fatal non‐suppurative meningoencephalitis in zoo animals of different species and a single wild carnivore as well as in apparently healthy yellow‐necked field mice (Apodemus flavicollis). Data regarding the background of this previously undiscovered pathogen, including clinical presentation of the disease, host range and distribution of the virus, are still limited. Here, three euthanized red‐necked wallabies (Macropus rufogriseus) from zoos of different areas in northeastern Germany were submitted for necropsy after presenting with apathy and therapeutically unresponsive neurological signs. A moderate to severe, non‐suppurative meningoencephalitis was diagnosed in all three cases. RusV was consistently detected via RT‐qPCR and RNA in situ hybridization in the brains of all wallabies. Other commonly known neuropathogens could not be detected. [ABSTRACT FROM AUTHOR]

Simple Summary: The red-necked wallaby is a small, herbivorous mammal that is native to Australia. In the study, the anatomy of arterial vessels that transport blood to the brain in this species was described and compared with that of other groups of mammals. The results of this research can contribute to further physiological and pathophysiological studies. This is the first description of this anatomical area that has been carried out in a marsupial species. The red-necked wallaby is a medium-sized marsupial species, which have increasingly been kept as pets around the world. In the study, the arterial blood supply for the brain in this species was described. The study was conducted on 50 specimens with two preparation methods. The main artery supplying the brain was the internal carotid artery. The arterial circle of the brain was closed from the caudal side. The anatomy of the arteries of the described region was compared with other groups of mammals. This is the first description of this anatomical area that has been carried out in a marsupial species. Understanding the anatomy of the circulatory system in the wallaby can be valuable for further physiological and pathophysiological studies. [ABSTRACT FROM AUTHOR]

Unlike their reptile-like ancestors with continuous tooth replacement, mammals have evolved to replace each tooth either only once, or not at all. In previous large-scale comparative studies, it has been suggested that this tooth replacement only occurs from a successional dental lamina produced lingually to the primary tooth. This study aims to document the complete tooth development and replacement pattern of the tammar wallaby (Macropus eugenii). The tammar wallaby is a diprotodont marsupial, a group defined by their two procumbent lower incisors. To provide a comprehensive documentation of the spatio-temporal pattern of tooth development, we used Lugol's Iodine staining and microCT scanning (diceCT) of embryos and pouch young into adulthood, resulting in high resolution 3D models for both soft and mineralised stages of development for all tooth positions. Our results reveal that the eponymous lower incisors are the successional generation at the third incisor locus, where the primary dentition initiates but never erupts. Furthermore, we track the development of the only replacement tooth, the permanent third premolar (P3), from initiation to eruption, and found it develops from the primary dental lamina, mesial to the dP3. This is contrary to the conventional view of lingual replacement from successional lamina in mammals. Our findings indicate that no functional tooth replacement occurs in the tammar wallaby, and expands the diversity of tooth replacement patterns found in mammals. We also conclude that since almost all marsupial and placental mammals produce replacement teeth from the distalmost deciduous premolar, this tooth should be considered homologous in these two groups. [ABSTRACT FROM AUTHOR]

Complete separation of endangered prey from introduced predators improves prey survival at the cost of reduced predator recognition and antipredator behaviours, termed 'prey naiveté'. Headstarting is a conservation strategy that has been used to improve the survival of juveniles for numerous species, whereby prey is separated from predators only in their vulnerable early life stage before release to the wild. However, by isolating prey from predators headstarting could compromise prey individuals' antipredator behaviour. Here, we evaluate the effects that headstarting has on the survival, dispersal, body condition and flight initiation distance (FID) of a terrestrial mammal, the bridled nailtail wallaby Onychogalea fraenata. Young bridled nailtail wallabies were isolated from predators in a 9.2 ha predator‐free fenced exclosure and were released into the wild once their body mass exceeded 3 kg. There was no difference in dispersal, body condition or survival of headstarted wallabies compared to wild‐raised wallabies. FID of headstarted wallabies assessed using night‐vision goggles was lower than wild‐raised wallabies in the week following release, but converged with that of wild‐raised wallabies within 4 weeks post‐release. Our results show that headstarting can be an effective conservation strategy for terrestrial mammals whose early life stages are vulnerable to introduced predators. [ABSTRACT FROM AUTHOR]

The opossum (Monodelphis domestica), with its sequenced genome, ease of laboratory care and experimental manipulation, and unique biology, is the most used laboratory marsupial. Using the mammalian methylation array, we generated DNA methylation data from n = 100 opossum samples from the ear, liver, and tail. We contrasted postnatal development and later aging effects in the opossum methylome with those in mouse (Mus musculus, C57BL/6 J strain) and other marsupial species such as Tasmanian devil, kangaroos, and wallabies. While the opossum methylome is similar to that of mouse during postnatal development, it is distinct from that shared by other mammals when it comes to the age-related gain of methylation at target sites of polycomb repressive complex 2. Our immunohistochemical staining results provide additional support for the hypothesis that PRC2 activity increases with later aging in mouse tissues but remains constant in opossum tissues. We present several epigenetic clocks for opossums that are distinguished by their compatibility with tissue type (pan-tissue and blood clock) and species (opossum and human). Two dual-species human-opossum pan-tissue clocks accurately measure chronological age and relative age, respectively. The human-opossum epigenetic clocks are expected to provide a significant boost to the attractiveness of opossum as a biological model. Additional epigenetic clocks for Tasmanian devil, red kangaroos and other species of the genus Macropus may aid species conservation efforts. [ABSTRACT FROM AUTHOR]

An albino infant wallaby was born to a mother with wild-type body color. PCR and sequencing analyses of TYR (encoding tyrosinase, which is essential for melanin biosynthesis) of this albino wallaby revealed a 7.1-kb-long DNA fragment inserted in the first exon. Since the fragment carried long terminal repeats, we assumed it to be a copy of an endogenous retrovirus, which we named walb. We cloned other walb copies residing in the genomes of this species and of another wallaby species. The copies exhibited length variation, and the longest copy (>8.0 kb) contained open reading frames whose deduced amino acid sequences were well aligned with those of gag, pol, and env of retroviruses. It is unknown through which of the following likely processes the walb copy was inserted into TYR: endogenization (infection of a germline cell by an exogenous virus), reinfection (infection by a virus produced from a previously endogenized provirus), or retrotransposition (intracellular relocation of a provirus). In any case, the insertion into TYR is considered to have been a recent event on an evolutionary timescale because albino mutant alleles generally do not persist for long because of their deleterious effects in wild circumstances. [ABSTRACT FROM AUTHOR]

Wallabies are small‐ to medium‐sized hopping marsupials and have large and flexible tendons in their hind limbs that act like springs. This study aimed to show the morphological pattern of the pes tendons in Bennett's wallaby. Two Bennett's Wallabies (Macropus rufogriseus) that died of natural causes have been used for this study. The pes was dissected using standard dissection techniques to expose the tendons around metatarsals and digits. The crural musculature of the hind limb was also dissected to identify the origin of the tendons. Tendons of m. extensor digitorum longus, m. extensor digitorum lateralis, m. extensor digiti II et III longus, m. flexor digitorum superficialis, m. flexor digitorum profundus and mm. interossei were the main identified tendons. Tendons of m. extensor digitorum longus attached to the distal phalanx of the fourth digit. The tendon of m. extensor digitorum lateralis had two insertion points, on the fourth and the fifth digits. The tendon of m. flexor digitorum superficialis bifurcates at the level proximal one‐third of the metatarsus. The relatively thinner branch inserted into the phalanx of the fifth digit, while the thicker splits and inserted to the medial and lateral surface of the distal end of the proximal phalanx of the fourth digit. Tendon of m. flexor digitorum profundus was the thickest tendon on the plantar surface, and it had four insertion points, which were the distal phalanges of the second, third, fourth and fifth digits. This study provides detailed information for future studies on the biomechanical and functional morphology of tendons in marsupials. [ABSTRACT FROM AUTHOR]

Temporal partitioning between ecologically similar species facilitates co‐occurrence and can influence the structure of mammalian assemblages. We studied diel activity patterns of two sympatric forest‐dwelling wallabies, the red‐legged pademelon (Thylogale stigmatica) and red‐necked pademelon (Thylogale thetis) in eastern Australia to better understand spatiotemporal partitioning between these closely related macropods. Temporally, both species displayed strongly crepuscular activity patterns typical of many macropod species; however, compared with T. thetis, T. stigmatica was less active during evening twilight and more active in the period prior to dawn. Spatially, T. stigmatica used dense forest cover exclusively throughout the 24‐hour cycle, while T. thetis divided its habitat spatiotemporally, spending the diurnal period under forest cover and the nocturnal period on pasture beyond the forest edge. In practical terms, this meant that T. stigmatica and T. thetis were fully spatially segregated at night, during the period they would be likely to do most of their foraging. We propose that the spatiotemporal partitioning observed is niche partitioning, and provides a mechanism for the co‐occurrence of these closely related species. [ABSTRACT FROM AUTHOR]

Knowledge of animal responses to fire is fundamental to wildlife management in fire‐prone ecosystems. Fire can influence the occurrence of large herbivores by altering the structure and composition of vegetation. However, how fire affects herbivore occurrence in many ecosystems is poorly understood. Large herbivores may be attracted to burnt areas due to higher foraging quality. Conversely, herbivores may avoid burnt areas due to heightened predation risk. We tested the influence of vegetation type and fire history variables on the occurrence of macropods at Booderee National Park in south‐eastern Australia. We documented macropod occurrence at 107 long‐term monitoring sites using spotlighting surveys conducted between 2003 and 2019. We modelled relationships between the occurrence of the eastern grey kangaroo (Macropus giganteus) and the swamp wallaby (Wallabia bicolor) with three fire history variables; time since fire, fire frequency and burn context (the proportion of the area surrounding each site that was recently burnt), as well as their interaction with vegetation type. We found both macropod species selected recently burnt sites, likely due to a higher abundance of preferred plants at these sites. Increasing fire frequency was associated with a reduced occurrence of the eastern grey kangaroo. The occurrence of both macropod species was significantly higher in forest sites, possibly reflecting higher foraging quality of grass and shrub species compared to woodland, heathland and shrubland sites. We suggest that if fire is used as a management tool, it is important to recognise potential feedbacks from increased foraging pressure from large herbivores. Future fire management will need to avoid burning areas of sensitive vegetation if local herbivores display pyric herbivory responses, and/or avoid small‐scale burns, which may concentrate foraging pressure. [ABSTRACT FROM AUTHOR]

Small macropodoid marsupials are well represented among Australia's extinct and threatened mammals. Population monitoring is central to understanding how remaining species respond to on‐going landscape change and threatening processes on private land and within managed conservation reserves. Camera trapping and occupancy modelling provide a reliable approach to monitor these often cryptic species. However, understanding the survey effort required to detect population declines of a given magnitude with high statistical certainty is often overlooked. We use empirical data from camera trapping and occupancy modelling to determine an optimal survey design for a regionally endangered population of the black‐striped wallaby. We established a 1200 ha grid of 60 cameras and sampled in three 30‐day intervals over a 1‐year period. We investigated factors that may influence occupancy and detection followed by power analyses with our broad objective being to devise a monitoring program that would be robust enough to detect a 50% decline with at least 80% power. This species was not detected at rainforest sites. Naïve occupancy within eucalypt forest was 0.42. The detection probability (using 5‐day detection occasions) varied with season (from 0.17 ± 0.04 in autumn to 0.34 ± 0.05 in spring). Occupancy was negatively influenced by shrub cover and negatively influenced by elevation. We found no apparent influence of dingo detection on occupancy or detection of the black‐striped wallaby. We explored different configurations of detection sites and number of survey occasions to satisfy our 50:80 criteria when initial occupancy was 0.40. Sampling 60 sites for a minimum of 30 days would satisfy these criteria. Power analyses can inform optimal designs for threatened species monitoring and similar investigations should be conducted for other threatened small macropods to assist their conservation. [ABSTRACT FROM AUTHOR]

Macropods are included among the species considered highly susceptible to Toxoplasma gondii infection. Clinically, it is difficult to distinguish between acute toxoplasmosis due to primary infection and reactivation of chronic latent infection in susceptible species until pathologic studies are performed. Here, we described the clinical cases and lesions found in two deceased Bennett's wallabies (Macropus rufogriseus) with a presumptive diagnosis of toxoplasmosis, as well as the genetic characterization of the T. gondii isolates obtained from these specimens. Both animals presented acute infection lesions in the lungs, liver, spleen and lymph nodes associated to T. gondii infection. Histopathology and immunohistochemistry also demonstrated tissue cysts of different sizes, indicating that the wallabies were previously infected with this parasite. Two isolates were obtained, one from each specimen and the molecular characterization was done; both isolates were the ToxoDB #116 genotype. This is the first study that reports the isolation of this particular genotype outside South America, and given the histopathological findings, it could be considered virulent for this species. The dynamics of infection that T. gondii is causing in definitive and intermediate hosts in a region allows us to know the risks to which the animals and humans that live in the area are exposed, and in the future to implement a preventive medicine plan against this parasite.

We present results from our analysis of the Hydra I cluster observed in neutral atomic hydrogen (H  i) as part of the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY). These WALLABY observations cover a 60-square-degree field of view with uniform sensitivity and a spatial resolution of 30 arcsec. We use these wide-field observations to investigate the effect of galaxy environment on H  i gas removal and star formation quenching by comparing the properties of cluster, infall, and field galaxies extending up to ∼5 R 200 from the cluster centre. We find a sharp decrease in the H  i -detected fraction of infalling galaxies at a projected distance of ∼1.5 R 200 from the cluster centre from |$\sim 85{{\ \rm per\ cent}}$| to |$\sim 35{{\ \rm per\ cent}}$|⁠. We see evidence for the environment removing gas from the outskirts of H  i -detected cluster and infall galaxies through the decrease in the H  i to r -band optical disc diameter ratio. These galaxies lie on the star-forming main sequence, indicating that gas removal is not yet affecting the inner star-forming discs and is limited to the galaxy outskirts. Although we do not detect galaxies undergoing galaxy-wide quenching, we do observe a reduction in recent star formation in the outer disc of cluster galaxies, which is likely due to the smaller gas reservoirs present beyond the optical radius in these galaxies. Stacking of H  i non-detections with H  i masses below |$M_{\rm {HI}}\lesssim 10^{8.4}\, \rm {M}_{\odot }$| will be required to probe the H  i of galaxies undergoing quenching at distances ≳60 Mpc with WALLABY. [ABSTRACT FROM AUTHOR]

CASE DESCRIPTION: A 7 - month - old hand - reared female Bennett's wallaby (Macropus rufogriseus) was evaluated for bilateral ocular opacity of 3 months' duration. CLINICALFINDINGS: On physical examination, the wallaby was in good overall condition. An ophthalmic examination revealed mature cataracts in both eyes (OU). The cataracts were suspected to have a nutritional origin as it has been described in hand-reared macropods. Results of tonometry were normal OU. Results of CBC and serum biochemistry were unremarkable. The wallaby was premedicated with medetomidine and ketamine hydrochloride. Ocular ultrasonography performed while the wallaby was anesthetized revealed a thickened and opaque lens, mildly heterogeneous vitreous humor, and no sign of retinal detachment OU. An electroretinogram confirmed functional retinae OU. TREATMENTANDOUTCOME: Surgery was considered necessary for welfare reasons. Phacoemulsification and vitrectomy were performed without intraoperative complication. The wallaby recovered uneventfully, and systemic NSAID, topical corticosteroid, and systemic and topical antimicrobial therapy were prescribed. One year later, the animal had vision OU. Physical examination did not show any vision-threatening postoperative complications. CLINICALRELEVANCE: The etiology of nutritional cataracts is not fully understood in macropods, but this condition is rather common in these species. To our knowledge, this is the first detailed report of a successful bilateral phacoemulsification and vitrectomy in a Bennett's wallaby. [ABSTRACT FROM AUTHOR]

Noninvasive genetic sampling (genetic tagging) of individuals is one of the most powerful and ethical tools for threatened species population monitoring. A recent review of the threats to Australia's rock-wallabies (Petrogale spp.) and the methods for their monitoring stated that noninvasive genetic sampling (faecal DNA analysis) is not viable for estimating population size and trends for species in this genus. We feel that it is important to respond as such statements have the potential to stifle the development and application of an important tool for threatened species monitoring and lead to lost opportunities for collection of high-quality data to inform conservation of these species. We take the opportunity to describe the breadth of successful application of noninvasive genetic sampling for monitoring rock wallabies and other mammal taxa, the research and development requirements for successful implementation of noninvasive DNA-based population monitoring and thoughts on why this powerful approach has not been implemented to its full potential in many jurisdictions. We need to be careful not to dismiss one of the most powerful and ethical threatened species monitoring tools due to lack of familiarity with the requirements for its implementation. [ABSTRACT FROM AUTHOR]

Summary: Cross‐cultural collaboration between Yawuru Country Managers (Rangers) and WWF‐Australia ecologists led to new detections of the Spectacled Hare‐wallaby (SHW), (Lagorchestes conspicillatus) in the west Kimberley region of Western Australia where it was presumed to be locally extirpated. This collaboration relied on the expertise of the Yawuru Country Managers to select specific locations for targeted field surveys and resulted in the confirmation of SHW on the Yawuru IPA for the first time in a decade. Subsequent remote camera trap surveys over a larger area included collaboration with two additional neighbouring Indigenous ranger groups, Karrajarri and Nyikina Mangala. These surveys investigated the spatial and temporal relationship between SHW and other mammals which may threaten (e.g., feral Cat [Felis catus], Dingo [Canis familiaris dingo]) or compete (e.g., Agile Wallaby [Macropus agilis]; Cattle [Bos taurus]) with them. We found a negative relationship between SHW and cat activity, suggesting that cats may limit the activity or abundance of SHW. Temporal portioning was evident between SHW and both Cattle and Agile Wallaby suggesting that SHW may avoid times when these species are most active. Further, we found a negative relationship between SHW occurrence and distance to fire scar edge burnt in current or previous fire season. This edge habitat is likely important to SHW because they may require recently burnt areas to forage and dense unburnt areas to shelter. This project highlights the benefits of cross‐cultural research and monitoring partnerships with Indigenous rangers as active observers and managers of their traditional lands. [ABSTRACT FROM AUTHOR]

Summary: Feral Cat (Felis catus) (cat) is a predator of the Bridled Nail‐Tailed Wallaby (BNTW) (Onychogalea frenata) living at Taunton National Park (Scientific) (Taunton). The aim of this study was to determine if traps and poison baits could be used to control feral cats without impacting non‐target species at Taunton. The techniques trialled included poison fresh meat baits and several types of traps presented in different ways and with various lures. Thirty‐one percent of fresh meat baits was taken during bait uptake trials; corvids removed 40% of these and dogs removed 16%. Cats were not detected, on camera traps, taking a bait. The elevated soft‐jaw traps (81 trap nights/cat) and single‐entry cage traps (98 trap nights/cat) were found to be the most successful of all the trap types trialled and had low amounts of by‐catch. Other trap types trialled took more than 166 trap nights to catch a cat. The elevated soft‐jaw trap configurations had the lowest amount of by‐catch (avg. 0.33%), and the log trap had the highest amount of by‐catch (1%). Ground‐set traps successfully trapped cats (305 trap nights/cat) but caught more by‐catch (0.9%) compared to the elevated soft‐jaw trap types and most wallabies caught in these traps had to be euthanised. [ABSTRACT FROM AUTHOR]

Summary: Agile Wallaby (Notamacropus agilis) has been in the diet of Aboriginal inhabitants of northern Australia for millennia. The species inhabits riparian zones and savannah woodlands, has a high rate of natural increase and can become pests in modified agricultural or plantation systems. Although the profitability of market‐based game harvesting appears marginal, local consumption could be incorporated into existing employment programmes on Aboriginal lands as a social enterprise. The legal environment is discussed, and further investigation and a trial as a pilot enterprise are recommended. [ABSTRACT FROM AUTHOR]

Summary: Every macropod population is unique in terms of the combination of species, site and management goals, so there is no universal 'best' method for surveying populations. We distinguish between different measures of abundance and the confidence a manager can place in them. We examine the separate components of survey methods: the survey platform, mode of detection and form of sampling. We also review the range of current methods available and highlight new developments, including their assumptions and limitations. To guide managers in choosing a method for their management context, we provide a decision matrix based on the behavioural ecology of the target species, the structure of habitat at the site and the porosity of the site boundary. To promote current best practice, we describe in detail four standard counting methods: direct count, sweep count, faecal accumulation rate and distance sampling. [ABSTRACT FROM AUTHOR]

Summary: Coincident with a decade of introduced predator suppression, there was an increase in populations of a range of native mammals at the Royal Botanic Gardens Victoria (Cranbourne). A small, regionally significant population of the Black Wallaby (Wallabia bicolor) grew exponentially from an estimated 0.6 individuals km−2 in 2001 to more than 70 km−2 in 2013. The measured mean annual instantaneous rate of increase derived from a regular spotlight survey was ˜0.37 and extrapolates to a doubling of the population approximately every 2 years. There was little indication that growth was abating as the population increased. Modelling predicted that in the absence of a decline in fertility or natural increase in mortality one third of the population would need to be shed annually to moderate or reverse growth and allow vegetation communities and small mammal habitats to recover. [ABSTRACT FROM AUTHOR]

A short gestation, low birth weight and presence of cutaneous exchange of O2 and CO2 comprise altricial features of newborn marsupials and that collectively implies a highly immature respiratory system. In the present study, we investigated various respiratory characteristics of the neonatal/postnatal tammar wallaby, a species of marsupial in which > 30% of the newborn's total O2 demands are supported by cutaneous rather than pulmonary gas exchange. The ventilatory response (HVR) to acute hypoxia (10% inspired O2) was absent in the newborn (1 day old) pouch young; a hypoxic hypometabolism contributed entirely to the hyperventilation (increased pulmonary convection requirement). A high (compared to older animals) resting metabolic cost to breathe and an inefficient respiratory system suggest the lack of a HVR might be due to an energetic constraint that impinges on their ability to sustain an increase in ventilation. The latter was supported by the inability of the newborn to tolerate metabolic-ventilatory stimulation following administration of the metabolic uncoupler, 2,4-dinitrophenol (2,4-DNP). At 1 week of age, the cost of breathing was reduced, which coincided with the expression of a significant ventilatory response to hypoxia, a more energetically efficient respiratory system, and tolerance to 2,4-DNP. These data suggest this species of marsupial is born with major respiratory insufficiency, and that their pronounced dependence on the skin for metabolic gas exchange is of critical importance for survival. [ABSTRACT FROM AUTHOR]

We use high-resolution ASKAP observations of galaxies in the Eridanus supergroup to study their H  i , angular momentum, and star formation properties, as part of the WALLABY pre-pilot survey efforts. The Eridanus supergroup is composed of three sub-groups in the process of merging to form a cluster. The main focus of this study is the Eridanus (or NGC 1395) sub-group. The baryonic specific angular momentum – baryonic mass (j b− M b) relation for the Eridanus galaxies is observed to be an unbroken power law of the form |$j_{\mathrm{b}} \propto M_{\mathrm{b}}^{0.57 \pm 0.05}$|⁠ , with a scatter of ∼0.10 ± 0.01 dex, consistent with previous works. We examine the relation between the atomic gas fraction, f atm, and the integrated atomic disc stability parameter q (the f atm− q relation), and find that the Eridanus galaxies deviate significantly from the relation owing to environmental processes such as tidal interactions and ram pressure affecting their H  i gas. We find that a majority of the Eridanus galaxies are H  i deficient compared to normal star-forming galaxies in the field. We also find that the star formation among the Eridanus galaxies may be suppressed owing to their environment, thus hinting at significant levels of pre-processing within the Eridanus sub-group, even before the galaxies have entered a cluster-like environment. [ABSTRACT FROM AUTHOR]

We present the Australian Square Kilometre Array Pathfinder (ASKAP) WALLABY pre-pilot observations of two 'dark' H  i sources (with H  i masses of a few times 108  |$\rm {M}_\odot$| and no known stellar counterpart) that reside within 363 kpc of NGC 1395, the most massive early-type galaxy in the Eridanus group of galaxies. We investigate whether these 'dark' H  i sources have resulted from past tidal interactions or whether they are an extreme class of low surface brightness galaxies. Our results suggest that both scenarios are possible, and not mutually exclusive. The two 'dark' H  i sources are compact, reside in relative isolation, and are more than 159 kpc away from their nearest H  i -rich galaxy neighbour. Regardless of origin, the H  i sizes and masses of both 'dark' H  i sources are consistent with the H  i size–mass relationship that is found in nearby low-mass galaxies, supporting the possibility that these H  i sources are an extreme class of low surface brightness galaxies. We identified three analogues of candidate primordial 'dark' H  i galaxies within the TNG100 cosmological, hydrodynamic simulation. All three model analogues are dark matter dominated, have assembled most of their mass 12–13 Gyr ago, and have not experienced much evolution until cluster infall 1–2 Gyr ago. Our WALLABY pre-pilot science results suggest that the upcoming large-area H  i surveys will have a significant impact on our understanding of low surface brightness galaxies and the physical processes that shape them. [ABSTRACT FROM AUTHOR]

We present observations of the Eridanus supergroup obtained with the Australian Square Kilometre Array Pathfinder (ASKAP) as part of the pre-pilot survey for the Widefield ASKAP L-band Legacy All-sky Blind surveY (WALLABY). The total number of detected H  i sources is 55, of which 12 are background galaxies not associated with the Eridanus supergroup. Two massive H  i clouds are identified and large H  i debris fields are seen in the NGC 1359 interacting galaxy pair, and the face-on spiral galaxy NGC 1385. We describe the data products from the source finding algorithm and present the basic parameters. The presence of distorted H  i morphology in all detected galaxies suggests ongoing tidal interactions within the subgroups. The Eridanus group has a large fraction of H  i -deficient galaxies as compared to previously studied galaxy groups. These H  i -deficient galaxies are not found at the centre of the group. We find that galaxies in the Eridanus supergroup do not follow the general trend of the atomic gas fraction versus stellar mass scaling relation, which indicates that the scaling relation changes with environmental density. In general, the majority of these galaxies are actively forming stars. [ABSTRACT FROM AUTHOR]

Invasive mammalian herbivores can have significant unwanted impacts on indigenous ecosystems and production landscapes. Their impacts are often mitigated using sustained lethal control or eradication. If eradication is the chosen option, it is critical to confirm where the pest population is distributed and prove that eradication has been achieved following the removal intervention. This form of pest management requires robust and quantitative estimates of surveillance. We compared the detection probabilities, derived surveillance system sensitivities (under standardized conditions), and cost of surveillance for four survey methods for invasive Bennett's wallabies (Notamacropus rufogriseus) in South Island, New Zealand: helicopter surveys with observers, helicopter surveys using a thermal imaging camera, a ground hunter with detector dogs, and camera traps. We found camera traps and ground hunters with dogs were the most sensitive surveillance methods (82% and 45% chance of detecting a wallaby assuming full search coverage of a 100‐ha area, respectively) and were most cost‐effective (62% and 85% cheaper than helicopter surveys with observers, respectively). However, although these methods are useful for surveying small areas (~1000 ha or less), capacity and time issues make them impractical for surveying large areas. The helicopter‐based methods will likely be more suitable for monitoring large areas (e.g., 10,000–50,000 ha) that need to be completed more rapidly than could be achieved using ground‐based methods. The model that we used for evaluating detection probability and surveillance sensitivity for different survey methods is highly applicable for managing a wide range of mammalian pests and confidently declaring their absence from an area. [ABSTRACT FROM AUTHOR]

We investigated whether human chorionic gonadotrophin (hCG), rather than porcine luteinising hormone (pLH), could induce ovulation in the tammar wallaby (Notamacropus eugenii) after priming with pregnant mare serum gonadotrophin (PMSG). pLH is effective, but is more expensive and supply is problematic. On Day 0 pouch young were removed (RPY) and 5 mg kg-1 of bromocriptine mesylate was administered to all non-pregnant wallabies (n = 12) to reactivate an oestrous cycle. On Day 20 RPY each female received 20IU PMSG i.m. and three days later (Day 23 RPY), the Single-Dose group (n = 6) received 500IU of hCG suspended in oil at 0900 hours, and the Multi-Dose group (n = 6) received 500IU of hCG at 0900, 1230 and 1630 hours. From Day 25 to Day 28 RPY copulatory plugs were observed in the Single-Dose (n = 4 of 6; Day 25.3 to 28.3 RPY) and Multi-Dose (n = 5 of 6; Day 25 to 28 RPY) groups. Autopsy on Day 31 RPY revealed that all females had reactivated, and despite all having large preovulatory follicles (4-6 mm) in both ovaries, no ovulations or embryos were observed. We conclude that hCG is not an effective source of exogenous LH for the induction of ovulation in the tammar wallaby. [ABSTRACT FROM AUTHOR]

The red-necked wallaby (Notamacropus rufogriseus) has a broad geographic range along the eastern seaboard of Australia, but ecological research on the mainland subspecies has been limited. We aimed to assess long-term monitoring (1974 to 2017) of abundance at a site in the Grampians National Park in Victoria. Our second aim was to evaluate trap success, sexual dimorphism, breeding seasonality, longevity and home range size from intensive studies (between 2008 and 2017) at this site. The abundance of red-necked wallabies increased over time, showing no negative effect of the arrival of the swamp wallaby (Wallabia bicolor) in the 1970s. Red-necked wallabies were highly trappable: 64% of individuals were retrapped at least once, one was retrapped 38 times, and trap success did not vary seasonally. Red-necked wallabies showed high site-fidelity, with no instances of long-range movements and no sex bias in likelihood of remaining on site. One female was regularly resighted for almost eight years after her initial capture and one male lived to an estimated age of 20 years. All births occurred in the first half of the year, with a marked peak of births in February, and over three-quarters of births occurred in February and March. Red-necked wallabies were highly sexually dimorphic: the largest male (24.5 kg) was nearly 10 kg heavier than the largest female (15 kg), and male home ranges were over five times larger than those of females. [ABSTRACT FROM AUTHOR]

We present sofia  2, the fully automated 3D source finding pipeline for the WALLABY extragalactic H  i survey with the Australian SKA Pathfinder (ASKAP). sofia  2 is a reimplementation of parts of the original sofia pipeline in the c programming language and makes use of OpenMP for multithreading of the most time-critical algorithms. In addition, we have developed a parallel framework called sofia -X that allows the processing of large data cubes to be split across multiple computing nodes. As a result of these efforts, sofia  2 is substantially faster and comes with a much reduced memory footprint compared to its predecessor, thus allowing the large WALLABY data volumes of hundreds of gigabytes of imaging data per epoch to be processed in real time. The source code has been made publicly available to the entire community under an open-source licence. Performance tests using mock galaxies injected into genuine ASKAP data suggest that in the absence of significant imaging artefacts sofia  2 is capable of achieving near-100 per cent completeness and reliability above an integrated signal-to-noise ratio (SNR) of about 5–6. We also demonstrate that sofia  2 generally recovers the location, integrated flux, and w 20 line width of galaxies with high accuracy. Other parameters, including the peak flux density and w 50 line width, are more strongly biased due to the influence of the noise on the measurement. In addition, very faint galaxies below an integrated SNR of about 10 may get broken up into multiple components, thus requiring a strategy to identify fragmented sources and ensure that they do not affect the integrity of any scientific analysis based on the sofia  2 output. [ABSTRACT FROM AUTHOR]