Response of a southern temperate marsupial, the Tasmanian pademelon (Thylogale billardierii), to historical and contemporary forest fragmentation

Despite only limited Pleistocene glacial activity in the southern hemisphere, temperate forest species experienced complex distributional changes resulting from the combined effects of glaciation, sea level change and increased aridity. The effects of these historical processes on population genetic structure are now overlain by the effects of contemporary habitat modification. In this study, 10 microsatellites and 629 bp of the mitochondrial control region were used to assess the effects of historical forest fragmentation and recent anthropogenic habitat change on the broad-scale population genetic structuring of a southern temperate marsupial, the Tasmanian pademelon. A total of 200 individuals were sampled from seven sites across Tasmania and two islands in Bass Strait. High mitochondrial and nuclear genetic diversity indicated the maintenance of large historical population sizes. There was weak phylogeographical structuring of haplotypes, although all King Island haplotypes and three Tasmanian haplotypes formed a divergent clade implying the mid-Pleistocene isolation of a far northwestern population. Both the mitochondrial and nuclear data indicated a division of Tasmanian populations into eastern and western regions. This was consistent with a historical barrier resulting from increased aridity in the lowland 'midlands' region during glacial periods, and with a contemporary barrier resulting from recent habitat modification in that region. In Tasmania, gene flow appears to have been relatively unrestricted during glacial maxima in the west, while in the east there was evidence for historical expansion from at least one large glacial refuge and recolonization of Flinders Island.     

The positive and negative conservation impacts of sheep grazing and other disturbances on the vascular plant species and vegetation of lowland subhumid Tasmania

Summary An important conservation question for grazed areas of lowland subhumid Tasmania is ‘what effects do different, practical disturbance regimes have on native vegetation?’ An experiment designed to determine the single and interactive effects of fire and sheep grazing was established at four sites with distinct vegetation types. There were significant interactive effects of fire and sheep grazing on vegetation attributes at all sites. An analysis of published and new data indicated that there were several vascular plant species that appeared dependent on sheep grazing for their persistence in the present landscape, while there were others that were intolerant of this disturbance but required other types of disturbance, such as mowing. However, most native species appeared to survive in a wide variety of disturbance regimes short of ploughing and fertilization. The implications of these results are that a variety of disturbance regimes is necessary to maintain biological diversity in this environment, and that the naturalness of the regime is not necessarily relevant to its use for conservation.     

Revision of the rove beetle genus Antimerus (Coleoptera, Staphylinidae, Staphylininae), a puzzling endemic Australian lineage of the tribe Staphylinini

The genus Antimerus Fauvel, 1878, endemic to eastern Australia and Tasmania and a phylogenetically enigmatic member of the large rove beetle tribe Staphylinini, is revised. The genus and each of its four previously known species are redescribed, and a lectotype is designated for Antimerus punctipennis Lea, 1906. Five species are described as new: Antimerus metallicussp. n., Antimerus jamesrodmanisp. n., Antimerus gracilissp. n., Antimerus bellussp. n. and Antimerus monteithisp. n., so that the number of known species in this genus now totals nine. For the first time Antimerus larvae are described, tentatively identified as Antimerus smaragdinus Fauvel, 1878, Antimerus punctipennis and Antimerus metallicus. Available distributional and bionomic data are provided for each species and summarized in the discussion. Adult and larval morphology of Antimerus and its distribution patterns are discussed in the broader context of new data on the evolution of the entire tribe Staphylinini, and with respect to the formation of the Australian fauna of this tribe. The phylogenetic position of Antimerus within Staphylinini remains unresolved pending a targeted formal study. However, a majority of currently available data suggests that it could be a basal member of the recently recovered monophyletic clade of Staphylinini tentatively called "Staphylinini propria".     

Disturbance and climatic influences on age structure of ponderosa pine at the pine/grassland ecotone, Colorado Front Range

Abstract. In the Colorado Front Range, disturbances and climatic variation influence stand structure of ponderosa pine (Pinus ponderosa) along the lower timberline ecotone. Over the past 100 years there has been a shift to a greater density and extent of ponderosa pine at the forest-grassland boundaries. Ponderosa pine regeneration at lower timberline appears to be influenced by fires in the 1860s and decreased grazing pressure in the 1970s–1980s. Climatic variation may also have influenced age structure, even though analyses of age structure at a 10-year class scale prevented the detection of climatic influences occurring at a finer scale. These changes in disturbance regimes, possibly together with moister springs/early summers, created favourable conditions for the increase in density and extent of ponderosa pine at lower timberline ecotone.     

Fire management in Tasmania’s Wilderness World Heritage Area: Ecosystem restoration using Indigenous‐style fire regimes?

Summary In many natural areas, changes in fire regimes since European settlement have resulted in adverse impacts on elements of biological diversity that survived millennia of land management by Indigenous people. Some of the rainforest and alpine elements that depend on south‐west Tasmania’s World Heritage Area have been in decline since European settlement of Tasmania due to an increase in the incidence of landscape‐scale fires in the period 1850–1940. Some of the buttongrass moorland elements that also depend on the region are in decline or impending decline because of a decreased incidence and/or size of burns since 1940. Will an Indigenous‐style fire regime serve the interests of biological diversity? We examine this question in the context of the fire ecology and fire history of south‐west Tasmania. From this assessment we argue that a return to Indigenous‐ style burning, modified to address contemporary issues such as the prevention of unplanned ignition, suppression of wildfires and burning to favour rare and threatened species may help to reverse trends towards ecosystem degradation in this region.     

The origin of a new focus of infection with Echinococcus granulosus in Tasmania.

Hydatid cysts were discovered in cattle on King Island, north of Tasmania, where Echinococcus granulosus was thought to have been eradicated. Using enzyme electrophoresis, isolates from King Island were compared genetically with isolates from Tasmania and the mainland of Australia. The genetic distinctness of the King Island isolates make it unlikely that they originated from a recent introduction from either Tasmania or mainland Australia. Alternative possibilities, that the infection resulted from a recent introduction from another source or from previously undetected persistence of E. granulosus on King Island, could not be distinguished from available data.     

Technique for washing nectar from the flowers of Tasmanian leatherwood (Eucryphia lucida Eucryphiaceae)

The technique for extracting floral nectar using micropipettes is often unsuited to flowers where nectar is produced in very small volumes and/or where nectar is highly viscous. An alternative technique for washing the viscous nectar from the flowers of Tasmanian leatherwood, Eucryphia lucida (Labill.) is described. Here, two washes with a known volume of distilled water removed 95% of total floral sugar. Using such a washing technique on exposed and bagged E. lucida flowers provided information on nectar production in this species that could not have been obtained using a standard micropipette extraction method.