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Echidnas are commonly known as 'spiny ant-eaters', but long-beaked echidnas (Zaglossus spp.) do not eat ants, whereas short-beaked echidnas (Tachyglossus aculeatus) eat other invertebrates as well as ants. The differences in skull morphology between short- and long-beaked echidnas are related to the differences in their diets, and I tested the hypothesis that there would be differences in beak length of short-beaked echidnas from populations with different diets. Published data on diet from echidnas from different parts of Australia show that echidnas from arid and semi-arid areas (subspecies acanthion) and Kangaroo Island (subspecies multiaculeatus) principally eat ants and termites, whereas the main dietary items of echidnas from south-eastern Australia (subspecies aculeatus) and Tasmania (subspecies setosus) are ants and scarab larvae. Using museum specimens and photographs I measured skull dimensions on echidnas from different parts of Australia: acanthion and multiaculeatus have narrower skulls and shorter beaks than aculeatus and setosus , with setosus being the only Australian subspecies where beak length exceeds cranium length. Australian short-beaked echidnas fall into two groups: aculeatus and setosus from the wetter east and south-east, which eat ant and scarab larvae, and the arid and semi-arid zone acanthion and multiaculeatus , with shorter, narrower skulls, and which eat ants and termites. Echidnas occur all over Australia, but echidnas from different regions vary greatly in the length of the spines and hair. This paper shows there are also big differences in beak length. Tasmanian echidnas have the longest beaks, whereas arid zone echidnas have very short beaks. Beak length is related to diet and feeding behaviour: longer beaks are better suited to probing for scarab larvae, while short beaks are better for ploughing through the soil for ants and termites. Diet, beak length and claw lengths divide Australian echidnas into two groups. [ABSTRACT FROM AUTHOR]

Deriving estimates of demographic parameters and the processes driving them is crucial for identifying wildlife management options. The short-beaked echidna (Tachyglossus aculeatus) is the most widely distributed native Australian mammal, yet little is known of its population dynamics due to its cryptic nature. Consequently, assessment of the impacts of climate and threats on echidna populations has been difficult. We analyse 19 years (1996–2014) of mark–recapture data to estimate survival and reproductive rates of a Tasmanian population of short-beaked echidna, and to evaluate the influence of regional weather patterns on its demographics. Population size showed high year-to-year variation, ranging from 1 to 40 echidnas km2 across the study area. Known-fate modelling of radio-tracked individuals suggested that climatic conditions impacted survival; average longevity was estimated at 16.7 years but only 4.8 years when the total spring/ summer rainfall was below 125 mm, and 6.25 in years when temperatures more frequently exceeded 32°C. Recruitment, estimated from Pradel analyses, was low in the population (β = 0.08) and not significantly affected by climate. These results are the first quantitative estimates of climate effects, survival, and recruitment for this species, and suggest that climateenhanced drying and temperature increase would pose a threat to echidna populations in Tasmania. [ABSTRACT FROM AUTHOR]

Mature forest is a key resource for hollow-using bats, but its importance in shaping where bats roost during breeding is not well understood. This lack of understanding limits the ability of forest managers to make informed decisions on the type, amount and spatial arrangement of mature forest to retain for bats in areas used for timber production. Using radio-telemetry, day roosts of three sympatric hollow-using bat species – the chocolate wattled bat (Chalinolobus morio), the Tasmanian long-eared bat (Nyctophilus sherrini) and the lesser long-eared bat (Nyctophilus geoffroyi) – were located in two forested landscapes in south-eastern Tasmania, Australia. By radio-tracking 24 bats in the maternity season, 76 roosts were located, with interspecific variation in roosting preferences evident at the roost, patch and landscape scale. Maternal colonies showed a clear selection for roosting in areas of the landscape containing the highest availability of mature forest, with smaller patches, strips and individual trees used to a greater extent for roosting in the landscape where mature forest was scarce. These findings showcase the importance of retaining mature forest at multiple spatial scales for hollow-using bats. Mature forest availability and spatial arrangement shape how bats use the landscape. Radio-tracking different species during the maternity season revealed the importance of retaining mature forest at multiple spatial scales. These findings provide insight into the type, amount and spatial arrangement of mature forest used by different bat species in a timber production landscape. By understanding the effectiveness of forest retention measures, on-ground forest management can be improved in the future. Photo by Lisa Cawthen. [ABSTRACT FROM AUTHOR]

Echidnas are egg‐laying mammals found across Australia, and in Tasmania they hibernate, resulting in a most unusual mating system: males enter hibernation in late summer–early autumn and arouse in late autumn–early winter to mate, although females are still hibernating. Groups of males compete for matings and both males and females mate with multiple partners. Females that mate early return to hibernation even when pregnant, and males continue to mate with pregnant females. We asked to what extent can the bizarre combination of behavioural and physiological features that characterize reproduction of Tasmanian echidnas be attributed to their phylogeny, and how much is a consequence of their ecology?To understand the interaction between energetics and the echidna mating system in determining the timing of echidna hibernation, we analysed data from an 18‐year study of a wild population of Tasmanian echidnas (Tachyglossus aculeatus setosus)Males in best condition arouse earliest and seek out suitable females, and females that mate early in the mating season re‐enter hibernation while pregnant.Competition between males drives early mating and while mating with males in the best condition could be advantageous for females and their young, egg‐laying in winter is potentially disadvantageous, and post‐mating hibernation by females is a means of delaying hatching of young until environmental conditions are more favourable. This post‐mating hibernation by females is usually disrupted by males which mate with them although they are already pregnant.Comparisons with other echidna populations suggest that a decreased activity period due to hibernation has not increased male–male competition.Similar competition between groups of males for access to females is seen in chlamyphorid armadillos, which occupy a similar ecological niche to echidnas. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

The size of an animal's home range is strongly influenced by the resources available within it. In productive, resource-rich habitats sufficient resources are obtainable within a smaller area, and for many species, home ranges are smaller in resource-rich habitats than in habitats with lower resource abundance. Location data on 14 male and 27 female echidnas (Tachyglossus aculeatus) fitted with tracking transmitters, in the southern midlands of Tasmania, were used to test the influence of habitat type on home-range size. We hypothesised that as woodland should offer more shelter, food resources and refuges than pasture, echidnas living in woodland would have smaller home ranges than those living in pasture areas. We found significant differences between the sexes. Male echidnas had a significantly larger mean home range than females and a quite different relationship between home-range size and habitat type from females. There was no relationship between the proportion of woodland within male home ranges and home-range size whereas female echidnas had a highly significant negative relationship. This suggests that home-range size of female echidnas is highly influenced by the amount of woodland within it, but the home-range size of male echidnas is controlled by factors other than habitat. This pattern is consistent with the spatial ecology of many other solitary species with a promiscuous mating system. The home ranges of females are scaled to encompass all necessary resources for successfully raising their young within a minimal area, whilst the large home ranges of males are scaled to maximise access to females. Home range size of female Tasmanian echidnas was strongly influenced by the proportions of woodland and pasture in their habitat with an inverse relationship between the amount of woodland and home range size. Males had larger home ranges, the size of which was not dependent on habitat type. [ABSTRACT FROM AUTHOR]

The article discusses research on the effectiveness of hair traps to survey mammals in the southern midlands of Tasmania. It references a study by Rachel L. Harris at the University of Tasmania School of Zoology in Hobart, and her colleague, published in an issue of "Australian Mammalogy." The researchers concluded that the choice of survey methods is a very important factor that can significantly affect the comprehensiveness as well as accuracy of survey results. They also found that hair-sampling methods are effective when surveying mammals, specifically when used together with other techniques like the track and scat analysis.

The short-beaked echidna is the most widely distributed endemic Australian mammal, and echidnas from different geographic areas differ so much in appearance that they have been assigned to several subspecies. In this paper, we present data obtained from free-ranging echidnas in southern Tasmania, and compare this with studies from other parts of Australia. In Tasmania mating occurs between early June and mid-September, and throughout Australia the normal breeding season lies within these limits. In echidnas from the more easterly parts of Australia reproduction closely follows hibernation, with Tasmanian echidnas showing a significant overlap between hibernation and reproduction. There is intense competition between males, and female echidnas from Tasmania show multiple matings. There are significant differences between echidnas from different areas of Australia in the use of nursery burrows and maternal care. One of the most dramatic differences is in duration of lactation: echidnas from Kangaroo Island wean the young at 204–210 days, but in Tasmania weaning occurs at 139–152 days, even though the masses of the young at weaning are comparable. [ABSTRACT FROM AUTHOR]

During hibernation there is a slowing of all metabolic processes, and thus it is normally considered to be incompatible with reproduction. In Tasmania the egg-laying mammal, the echidna (Tachyglossus aculeatus) hibernates for several months before mating in mid-winter, and in previous studies we observed males with females that were still hibernating. We monitored the reproductive activity of radio-tracked echidnas by swabbing the reproductive tract for sperm while external temperature loggers provided information on the timing of hibernation. Additional information was provided by camera traps and ultrasound imaging. More than a third of the females found in mating groups were torpid, and the majority of these had mated. Some females re-entered deep torpor for extended periods after mating. Ultrasound examination showed a developing egg in the uterus of a female that had repeatedly re-entered torpor. The presence of fresh sperm in cloacal swabs taken from this female on three occasions after her presumed date of fertilization indicated she mated several times after being fertilized. The mating of males with torpid females is the result of extreme competition between promiscuous males, while re-entry into hibernation by pregnant females could improve the possibility of mating with a better quality male. [ABSTRACT FROM AUTHOR]

The article presents research which examines the importance of temperature dataloggers in monitoring tree hollow-using mammals in Tasmania. Radio-telemetry, remote cameras and fiber optics are instruments used to capture the images of these wild animals at Kellevie and Melton Mowbray sites. In addition, metal washer with surgical cotton attached is applied to identify the temperature changes. It found that brushtail possum species showed significant role to the changes of temperature.