Australian Journal of Zoology
Volume 60
Number 4 2012
Perch substrate observations were compared with substrate availability for the wallum sedge frog (Litoria olongburensis) in wetlands throughout its mainland distribution. The proportion perched on sedges with upright form was much higher than expected based on availability. Knowledge of preferred perch species should aid habitat assessment and regeneration.
A population of long-nosed potoroos was monitored for five years. Twelve pouch young were assigned paternity. One female produced young with multiple males, and another with a single male, suggesting that the mating system is not entirely promiscuous. Sires were on site for significantly longer than non-sires but were not significantly larger.
We isolated 25 new polymorphic microsatellite markers from the eastern mosquitofish (Gambusia holbrooki). These markers will be useful in documenting the population genetics of the mosquitofish, an important pest in Australian freshwater ecosystems and a model species for evolutionary experiments.
The southern short-tailed opossum is a small terrestrial marsupial that inhabits the Pampas grasslands of Argentina. We found that this species showed an annual replacement of generations which, along with other traits such as strong reproductive seasonality and pronounced sexual dimorphism, supports a semelparous life cycle for this opossum.
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 musculature of D. lumholtzi differed from that of terrestrial macropdines, suggesting adaptation to the demands of arboreal locomotion.
Pelage hair follicles of the southern elephant seal, Mirounga leonina (Linn.), are active for only 2–3 months before, during and after the moult haul-out. While implantation of blastocysts can and does take place well before completion of hair replacement and may be triggered by some astral event, the timing of the moult appears to depend more on nutritional status than environmental cues.
Photo by Graham Blight.
We examined two mechanisms for inbreeding avoidance in the group living lizard Egernia stokesii. We found no evidence for sex-biased dispersal at seven rocky outcrop 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. Photo by A. Fenner.
Using radio-tracking, trapping and microsatellite data, we defined the mating system of the northern bettong as ‘overlap promiscuity’. Most dispersal was male-biased and occurred over short distances (1.3 km versus 0.9 km). Female young often settled next to their mother, while males avoided nesting within their father’s home range.
Photo by Lisa Pope.