Understanding habitat requirements for a threatened species is important for recovery planning and management of threatening processes. This study examines utilisation of wetland habitat by the threatened wallum sedge frog (Litoria olongburensis), which breeds in acidic waters of coastal sandy lowlands in subtropical eastern Australia. Habitat utilisation was determined by comparing perch substrate observations with perch substrate availability in wetlands occupied by the species throughout its mainland distribution range. A high proportion (75.3%) of adult wallum sedge frogs perched on upright sedges, comprising Baumea, Schoenus and Chorizandra species, which was much higher than expected on the basis of availability (P < 0.001). Baloskion pallens, a thin sedge-like herbaceous plant, was utilised by 12.1% of the frogs, which was lower than expected on the basis of availability (P = 0.020). Other herbaceous species and shrubs were also utilised significantly less than expected. The identification of preferred perch species is critical for impact assessment and mitigation activities, including design, construction, restoration and maintenance of wetlands suitable for the survival and reproduction of the wallum sedge frog.

The potoroids are a small group of cryptic macropodoid marsupials that are difficult to directly monitor in the wild. Consequently, information regarding their social and mating systems is limited. A population of long-nosed potoroos (Potorous tridactylus) on French Island, Victoria, was monitored from June 2005 to August 2010. Tissue samples were collected from 32 (19 ♂, 13 ♀) independent potoroos and 17 pouch young. We aimed to determine the genetic mating system and identify patterns of paternity through genotyping individuals at 10 microsatellite loci. Additionally, we investigated the importance of body mass and site residency as strategies in securing paternity. Twelve of the 17 pouch young sampled were assigned paternity with confidence to five males. Multiple pouch young were sampled from two long-term resident females, one of which had 10 pouch young sired by multiple partners, with some repeat paternity, while the other had three young sired by one male, suggesting that the mating system is not entirely promiscuous. Sires were recorded on site for significantly longer periods than non-sires but were not significantly larger than non-sires at conception. This suggests that sires employ strategies other than direct competition, such as scramble competition, to secure paternity in P. tridactylus.

We isolated 25 new polymorphic microsatellite markers from the eastern mosquitofish, Gambusia holbrooki. Initially, 454 shotgun sequencing was used to identify 1187 loci for which primers could be designed. Of these 1187, we trialled 48 in the target species, 40 of which amplified a product of expected size. Subsequently, those 40 loci were screened for variation in 48 individuals from a single population in Canberra, Australia. Twenty loci were in Hardy–Weinberg equilibrium and polymorphic, with observed heterozygosity ranging from 0.04 to 0.72 (mean: 0.45 ± 0.18) and the number of alleles per locus ranged from 2 to 5 (mean: 3.20 ± 1.05). These loci will be useful in understanding genetic variation, paternity analysis and in managing this species across both its native and invasive range.

The genus Monodelphis is one of the most species rich among Neotropical marsupials. Despite this, little is known about most of the species. One of the most enigmatic species is M. dimidiata, a small terrestrial opossum that inhabits the Pampean region of Argentina, which is suspected to be a semelparous breeder. From 2005 to 2008, we conducted seasonal live trapping in near-pristine marshy grasslands and agroecosystems of the Pampean region in order to evaluate the population trends of this species and the occurrence of semelparity. M. dimidiata was characterised by a low abundance in the study area. The average density was higher in grasslands than in agroecosystems, and it appeared to be influenced by vegetative cover. The onset of the breeding season occurred during spring when the opossums showed a sudden increase in body size. Given that mature individuals were not found beyond autumn, the findings suggest an annual cycle for this species. In addition, this abrupt maturation resulted in a pronounced sexual dimorphism that, together with the strong reproductive seasonality and a likely polygynous mating system, supported previous claims that the species is semelparous. Our results also emphasise the importance of native grassland habitat for the maintenance of stable populations of M. dimidiata.

Tree-kangaroos (Dendrolagini) are Australasian marsupials that inhabit tropical forests of far north-eastern Queensland and New Guinea. The secondary adaptation of tree-kangaroos to an arboreal lifestyle from a terrestrial heritage offers an excellent opportunity to study the adaptation of the musculoskeletal system for arboreal locomotion, particularly from a template well adapted to terrestrial bipedal saltation. We present a detailed descriptive study of the hind limb musculature of Lumholtz’s tree-kangaroo (D. lumholtzi) in comparison to other macropodines to test whether the hind limb musculature of tree-kangaroos is functionally adapted to the different mechanical demands of locomotion in the uneven three-dimensional arboreal environment. The hind limb musculature of Lumholtz’s tree-kangaroo (Dendrolagus lumholtzi), the western brush wallaby (Macropus irma), the western grey kangaroo (Macropus fuliginosus) and the quokka (Setonix brachyurus) are described. The hind limb anatomy of D. lumholtzi differed from that of the terrestrial macropodines in that the muscles had a greater degree of internal differentiation, relatively longer fleshy bellies and very short, stout tendons of insertion. There was also a modified arrangement of muscle origins and insertions that enhance mechanical advantage. Differences in the relative proportions of the hind limb muscle mass between tree-kangaroos and terrestrial macropodines reflect adaptation of the limb musculature of tree-kangaroos for arboreal locomotion. The hind limb musculature of Setonix was different to that of both Dendrolagus and Macropus, possibly reflecting its more basal phylogenetic position within the Macropodinae.

Hair growth stages, anagen, catagen and telogen, were diagnosed histologically in skin samples taken at Macquarie Island from 103 southern elephant seals – 11 pups, 56 immatures, 23 adult females and 13 adult males – in order to correlate hair follicle activity with field observations of this species’ unusual type of moult. The duration of the hair growth cycle in fully developed follicles is ∼12 weeks. Hair follicles are active for 2–3 months before, during and after the moult haul-out and are resting at other times of the year. A high proportion of adult females appear to commence hair growth between 4 January and 2 February. While implantation of the blastocyst may be triggered by some astral event, such as daylength, it does not depend on completion of the moult, as suggested by previous authors. The pelage cycle is possibly controlled by an endogenous rhythm established during follicle development and subsequent growth and shedding of the natal coat, but the timing and duration of the moult haul-out may depend on the nutritional status of seals within each particular age–sex class. In adult seals this will be governed by terrestrial activities that involve fasting during the breeding and moulting seasons, whereas immature seals haul out and fast, not only to moult but some also come ashore and rest during winter. There may also be metabolic demands for materials for the complete replacement of the pelage, and much of the stratum corneum.

Egernia stokesii is a monogamous and group-living species of Australian scincid lizard. We used genotype data from 10 microsatellite loci to examine evidence for sex-biased dispersal and kin-based discrimination as mechanisms for inbreeding avoidance of E. stokesii within seven rocky outcrops in the southern Flinders Ranges of South Australia. We also examined the relatedness of individuals observed using the same crevice within groups. We found no evidence for sex-biased dispersal at these sites, but found that adult lizards of the opposite sex observed using the same crevice were less related to each other than expected by chance. Our results suggest a behavioural mechanism for minimising inbreeding in large related aggregations of this species.

The northern bettong (Bettongia tropica) (Potoroidae), is an endangered macropod with a restricted distribution. We combined radio-tracking and trapping data with microsatellite genotypes to infer the mating system and local dispersal patterns of this species, and discuss their relevance to translocations. We defined the mating system as ‘overlap promiscuity’ (sensu Wittenberger 1979), though we cannot rule out serial monogamy. We found significant effects of proximity (average distance between parents = 190 m) and male weight, but not size, on the likelihood of paternity, suggesting that closer, heavier males have greater mating success. The average distance between putative pairs of relatives suggested that most dispersal occurred over short distances, with the distance between ‘related’ females significantly lower than that between related males (0.9 km versus 1.3 km). A spatial autocorrelation analysis showed high female relatedness across distances of up to 435 m, equivalent to half an average home range width. Conversely, male pairs had low relatedness across 0 to 870 m. These results suggested that female young often settle next to their mother, while males avoid nesting within their father’s home range. Both limited natal and ‘mating’ dispersal may have contributed to the strong genetic structure previously reported for this species.