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During the construction of a 3.6m i.d. flow transfer tunnel in Hull, UK, a 100m length of completed tunnel collapsed. In her Harding Prize finalist paper; Sarah Munks, former tunnel [...]

The platypus (Ornithorhynchus anatinus) is one of the world's most evolutionarily distinct mammals, one of five extant species of egg-laying mammals, and the only living species within the family Ornithorhynchidae. Modern platypuses are endemic to eastern mainland Australia, Tasmania, and adjacent King Island, with a small introduced population on Kangaroo Island, South Australia, and are widely distributed in permanent river systems from tropical to alpine environments. Accumulating knowledge and technological advancements have provided insights into many aspects of its evolutionary history and biology but have also raised concern about significant knowledge gaps surrounding distribution, population sizes, and trends. The platypus' distribution coincides with many of Australia's major threatening processes, including highly regulated and disrupted rivers, intensive habitat destruction, and fragmentation, and they were extensively hunted for their fur until the early 20th century. Emerging evidence of local population declines and extinctions identifies that ecological thresholds have been crossed in some populations and, if threats are not addressed, the species will continue to decline. In 2016, the IUCN Red Listing for the platypus was elevated to "Near Threatened," but the platypus remains unlisted on threatened species schedules of any Australian state, apart from South Australia, or nationally. In this synthesis, we review the evolutionary history, genetics, biology, and ecology of this extraordinary mammal and highlight prevailing threats. We also outline future research directions and challenges that need to be met to help conserve the species.

Focuses on the habits of the platypus in Australia. Habitat; Reproduction; Nutrition.

Adult male and female platypuses were radio-tracked in summer and winter at Lake Lea, north-western Tasmania. They appeared to exhibit greater diurnality, particularly during winter months, a greater degree of overland movement and more frequent use of non-earth refuge sites than do animals inhabiting mainland water bodies. Individuals foraged continuously for up to 16 h, with longer foraging bouts observed during the winter tracking period. Foraging range varied between 2 and 58 ha, with no significant differences observed between the sexes or seasons. All platypuses foraged predominantly in the lake; however, a number of animals were observed moving overland to and from waterbodies and burrows. Burrows were located on lake, creek and pool edges. A high percentage of burrows (25%) were located within dense sedge tussocks and scrub vegetation. Both the terrestrial activity and more opportunistic burrow-site selection may be related to reduced predation pressure in Tasmania.

The effects of forest type and disturbance on specific reproductive traits are unknown for many forest-dwelling mammals. We assessed whether differences in forest type and disturbance influenced key reproductive traits of an arboreal marsupial, the common brushtail possum (Trichosurus vulpecula), in Tasmania, Australia. Trapping was conducted in spring-summer and autumn-winter during 2007–2008 at 6 dry Eucalyptus forest sites (3 regenerating and 3 relatively undisturbed) in southeast Tasmania and 4 wet Eucalyptus forest sites (2 regenerating and 2 relatively undisturbed) in the northeast. We aged pouch young and assessed the body condition of back young. We milked females captured during the late stage of lactation and compared the nutritional composition of milk among sites. Births occurred slightly earlier at the northern sites than at those in the south. Female body mass and offspring body condition and survival were similar across sites. Milk composition also was similar across sites, but possums in dry, undisturbed forest, primarily at 1 site, produced milk with significantly higher fat content; however, we found no evidence of a difference in body condition or survival of young that could be attributed to a difference in milk quality. Although forest type and disturbance influence demography and breeding frequency in the brushtail possum populations we studied, these population-level differences are not linked to variations in the reproductive traits examined here. We conclude that the brushtail possum is a physiologically resilient species, and the ability of individual females to reproduce successfully is relatively insensitive to forest type or habitat disturbance.

We investigated the activity patterns of platypuses, Ornithorhynchus anatinus, at Lake Lea, a subalpine lake in Tasmania. Platypuses were equipped with activity loggers or time-depth recorders, which allowed constant recordings for up to 48 days. The recordings revealed an unexpectedly high variety of foraging behaviors. Although nocturnal activity, as reported from other habitats, was still predominant, diurnal activity as well as highly fragmented activity patterns were common. Mean foraging duration was 12.4 h/day, with some animals foraging continuously for up to 29.8 h. Daily emergence and return times as well as durations of daily foraging trips varied considerably. At least 2 animals showed a distinct shift in activity pattern related to the lunar cycle. Season and water temperature affected platypus behavior. Foraging durations were longer and activity levels were higher in winter. In contrast to observations in river systems, temporal separation likely served as a mechanism to avoid intraspecific competition, and was particularly important for adult males during the breeding season. Dominant males were preferentially nocturnal, whereas lower-ranked males adopted more variable or fragmented activity patterns.