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Aim: South-eastern Australia is a climate change hotspot with well-documented recent changes in its physical marine environment. The impact on and temporal responses of the biota to change are less well understood, but appear to be due to influences of climate, as well as the non-climate related past and continuing human impacts. We attempt to resolve the agents of change by examining major temporal and distributional shifts in the fish fauna and making a tentative attribution of causal factors. Location: Temperate seas of south-eastern Australia. Methods: Mixed data sources synthesized from published accounts, scientific surveys, spearfishing and angling competitions, commercial catches and underwater photographic records, from the 'late 1800s' to the ' present', were examined to determine shifts in coastal fish distributions. Results: Forty-five species, representing 27 families (about 30% of the inshore fish families occurring in the region), exhibited major distributional shifts thought to be climate related. These are distributed across the following categories: species previously rare or unlisted (12), with expanded ranges (23) and/or abundance increases (30), expanded populations in south-eastern Tasmania (16) and extralimital vagrants (4). Another 9 species, representing 7 families, experienced longerterm changes (since the 1800s) probably due to anthropogenic factors, such as habitat alteration and fishing pressure: species now extinct locally (3), recovering (3), threatened (2) or with remnant populations (1). One species is a temporary resident periodically recruited from New Zealand. Of fishes exhibiting an obvious poleward movement, most are reef dwellers from three Australian biogeographic categories: widespread southern, western warm temperate (Flindersian) or eastern warm temperate (Peronian) species. Main conclusions: Some of the region's largest predatory reef fishes have become extinct in Tasmanian seas since the ' late 1800s', most likely as a result of poor fishing practices. In more recent times, there have been major changes in the distribution patterns of Tasmanian fishes that correspond to dramatic warming observed in the local marine environment.

AIM: Prescribed fire is a common land management for reducing risks from unplanned fires. However, the universality of such effectiveness remains uncertain due to biogeographical variation in fuel types, climatic influences and fire regimes. Here, we explore biogeographical patterns in the effectiveness of prescribed fire by calculating leverage (the reduction in unplanned area burnt resulting from recent previous area burnt) across south‐eastern Australia over a 25 year period. LOCATION: The 30 bioregions of south‐eastern Australia. METHODS: We quantified leverage in each bioregion from fire records from 1975–2009, controlling for variation in annual weather. We also identified potential drivers of variation in leverage by relating the bioregional leverage values to measures of fuel type and growth, climate, and weather extremes. RESULTS: Leverage was inferred in four bioregions while in the other 26 bioregions no leverage was detected or prescribed fire had the opposite effect (fire‐follows‐fire). Leverage occurred in the forested eastern section of the study area, where rainfall, fuel load and fire activity is high and fire weather is mild. In all bioregions, weather was a stronger predictor than past‐fire extent of area burnt in a particular year. MAIN CONCLUSIONS: Our analysis of leverage shows that the effectiveness of prescribed fire varies regionally in predictable ways, which means that fuel management strategies applied in one region are not necessarily applicable in another. In most bioregions prescribed burning is likely to have very little effect on subsequent extent of unplanned fire, and even in regions where leverage occurs, large areas of treatment are required to substantially reduce the area burned by unplanned fire.

Aim The distribution and abundance of forest biodiversity can be shaped by multiple drivers, including disturbances like wildfires. We quantified the influence of wildfire severity and bird life history attributes on temporal patterns of bird site occupancy. Location Wet eucalypt forests of Victoria, Australia. Methods We employed a Before, After, Control, Impact experimental design, gathering occupancy data on birds 5 years before, and for 10 years after, a wildfire in 2009. We quantified post‐fire decline and then recovery on sites subject to high‐severity fire, comparing these temporal patterns with those for birds at sites that were unburnt or burnt at moderate severity. We also tested the influence of life history attributes on bird responses to wildfire. Data were analysed using joint species distribution modelling, accounting for imperfect detection. Results We found a two‐way interaction between fire severity and time period for overall bird site occupancy. The largest change between time periods was on sites burnt at high severity where bird occupancy declined immediately after fire followed by a strong recovery. Occupancy patterns remained largely unchanged on unburnt sites. For many individual species, interactions between fire severity and time period were similar to overall species occupancy. On sites subject to high‐severity fire, most species recovered to pre‐fire levels within 6 years. We found no evidence of a three‐way interaction between fire severity, time period, and life history attributes, with all trait groups of birds examined largely recovered to pre‐fire site occupancy levels 10 years post‐fire. Main conclusions The Victorian 2009 wildfires were severe, but their impacts on common bird species were relatively short‐lived, with immediate post‐fire declines mostly reversed within ~10 years. Rapid post‐fire stand regeneration appears a likely driver of these responses and may account for the relatively limited influence of life history attributes on bird species recovery. However, diet influenced bird species occupancy after fire, with nectivores recovering slower than insectivores on sites subject to high severity fire. Our findings may be relevant to other forests types globally where there can be rapid post‐fire vegetation growth and stand regeneration.

1. To understand species losses from disturbed landscapes, it is important to distinguish the effects of degraded environmental conditions from those caused by barriers to dispersal between habitat patches. To assess the relative importance of these effects, we developed a new approach using permutation and association tests applied to rank abundance data, using the invertebrate fauna of two rivers in two seasons. 2. Our study streams were Hughes Creek and Seven Creeks, in south-eastern Australia, which have both been degraded by agriculture in downstream sections. We collected benthic invertebrates and also dispersing individuals (drift, terrestrial adults) during two seasons in 2007-2008. Study sites spanned strong environmental gradients as well as the main dispersal route (up- and down-channel). Environmental data were analysed to set up permutation tests on rank abundances. Survey and disperser data were contrasted using contingency table analyses. 3. The results suggest dispersal plays a strong role in community structure. Environmental effects were evident and strongest upstream, but evidence of environmental effects was weak over much of the gradient. Many species had different distributions in different data sets or dispersers that were abundant at locations distant from centres of benthic distribution. 4. Our results differ from many studies, but few have been able to evaluate dispersal effects directly. Our method provides a practical approach for evaluating the role dispersal plays in driving species abundance patterns across landscapes, thus bridging a gap between theory and practice. 5. Synthesis and applications. Managers typically use indices of ecosystem health that assume environmental conditions largely determine species diversity and abundance. Dispersal between habitat patches is known to be important, but there are no reliable methods to assess the role dispersal may play. We provide an approach that allows both dispersal and environmental effects on species distributions to be evaluated from survey data. This may open the way for dispersal information to be incorporated into management actions. Additionally, the approach should allow improved siting of restoration projects that depend greatly on successful dispersal of individuals for successful outcomes.

Aim: Management practices in the landscape matrix can have significant effects on the spatial distribution of animals within adjacent protected areas. This has been well established in agricultural and forested areas, but less is known about how management of the suburban matrix affects adjacent reserves. We argue that it is critically important to understand the impact of suburban management on reserves, as flawed planning decisions can have negative conservation outcomes and waste limited resources. Location: Canberra, Australian Capital Territory, Australia. Methods: We examined bird distribution patterns in suburbs and adjacent reserves to the effects of two suburban management practices: (1) street tree planting and (2) boundary design. We focused on three groups of birds with known responses to urbanization: native urban-intolerant species (native avoiders), native urban-tolerant species (native adapters) and exotic urban-tolerant species (exotic adapters). Results: We found that suburbs with ≥ 30% native (Eucalyptus) street trees and reserves adjacent to these suburbs had significantly higher bird species richness, native adapter species richness and probability of reporting exotic adapters than those with exotic trees. The type of street trees, however, did not affect the probability of reporting native avoiders. These species were more likely to be reported when habitat complexity was high. Only native adapters responded to boundary design, with higher species richness when the boundary type was a local or unsealed road as opposed to an arterial road. Main conclusions: Native street trees provide foraging resources for birds that would be reduced or absent in exotic streetscapes, enabling native streetscapes to support a rich community of birds. Furthermore, native streetscapes increase bird richness and diversity in adjacent reserves. This result has important conservation implications for suburb and reserve management practices. Our study provides evidence that the establishment and retention of native suburban streetscapes is an important management strategy for improved bird conservation.

Aim: Apex predators often exert strong, top-down effects on ecosystems, and their removal can result in the dramatic reorganization of ecosystems owing to herbivores and smaller predators becoming the dominant trophic-regulating species. However, field studies designed to understand the influence that apex predators have on ecosystems are hampered by the large spatial and temporal scales required. Here, we use pre-existing datasets to test predictions on the direct and indirect effects of apex predators on mammals and vegetation generated from trophic cascade theory and the mesopredator release hypothesis. Location: Forests of south-eastern Australia. Methods: We applied quantile regression to published data collected at 44 sites during the 1980s and 1990s. We investigated inter-relationships between abundance indices of an apex predator, the dingo (Canis dingo), introduced mesopredators, herbivores, ground-dwelling medium-sized mammals and small mammals, and inter-relationships between habitat complexity and abundances of dingoes and macropods. Quantile regression is well suited for investigating limiting factors of response variables, especially when the observations are made at large temporal and spatial scales. Results: In accordance with trophic cascade theory, dingo abundance was negatively associated with macropod abundance and macropod abundance was negatively associated with habitat complexity; however, dingo abundance was not correlated with habitat complexity. Similarly, in accordance with the mesopredator release hypothesis, dingo abundance was correlated negatively with red fox abundance and red fox abundance was negatively associated with the abundance of ground-dwelling medium-sized mammals, but, dingo abundance was not correlated with the abundance of medium-sized ground-dwelling mammals. Main conclusions: Our results suggest that the direct suppressive effects of the dingo on macropods and foxes occur simultaneously, but that their indirect effects on lower trophic levels are comparatively weak. Our study provides evidence that the effects of apex predators on other species can be exerted across large spatial scales and become manifest on species at multiple trophic levels.

AIM: Broad‐scale patterns of heat stress play an important role in shaping the geographical distributions of many species and may differ from large‐scale changes in average temperatures. For species living on rocky intertidal shores extreme heat stress occurs when hot dry aerial conditions coincide with midday low tides. We used empirical and modelled temperature data, and estimates of cumulative aerial exposure and solar radiation, in order to test the hypothesis that heat stress on Australian rocky intertidal shores decreases with increasing latitude. LOCATION: Rocky intertidal shores of south‐eastern Australia spanning > 1500 km and 13° of latitude (26°24′23″ S to 39°07′47″ S). METHODS: In situ temperature measurements, hourly tidal elevations and daily solar radiation taken over three consecutive summers (December 2009–February 2012) were used to quantify latitudinal variability in extreme heat stress, cumulative aerial exposure and solar radiation, respectively. Comparisons between hourly in situ temperatures and meteorological data were used to produce a large‐scale statistical model capable of estimating intertidal substratum temperatures during daytime low‐tides, which was then extrapolated across 22 locations. RESULTS: Heat stress estimated using in situ loggers deployed across five east coast locations typically did not decline with increasing latitude and neither did midday exposure or solar radiation. The meteorological model proved to be a successful method for estimating rocky shore heat stress and in contrast to the empirical data displayed strong latitudinal trends in mean daily maxima and cumulative heat stress. Modelled acute heat stress (i.e. summer maxima), however, did not decline with increasing latitude, as there was greater thermal variability at higher latitudes. MAIN CONCLUSIONS: The meteorological model developed in this study represents a useful approach for estimating broad‐scale patterns of heat stress on rocky intertidal shores. Results also indicate that latitudinal patterns of acute and chronic heat stress may differ from average temperatures, which are commonly assumed to decline with increasing latitude. Such broad‐scale patterns of thermal stress as described in this study will significantly contribute to our ability to understand the impact of climate change on vulnerable rocky intertidal communities.

There is a need for more Southern Hemisphere phylogeography studies, particularly in Australia, where, unlike much of Europe and North America, ice sheet cover was not extensive during the Last Glacial Maximum (LGM). This study examines the phylogeography of the south-east Australian montane tree species Eucalyptus regnans. The work aimed to identify any major evolutionary divergences or disjunctions across the species' range and to examine genetic signatures of past range contraction and expansion events. South-eastern mainland Australia and the large island of Tasmania. We determined the chloroplast DNA haplotypes of 410 E. regnans individuals (41 locations) based on five chloroplast microsatellites. Genetic structure was examined using analysis of molecular variance (AMOVA), and a statistical parsimony tree was constructed showing the number of nucleotide differences between haplotypes. Geographic structure in population genetic diversity was examined with the calculation of diversity parameters for the mainland and Tasmania, and for 10 regions. Regional analysis was conducted to test hypotheses that some areas within the species' current distribution were refugia during the LGM and that other areas have been recolonized by E. regnans since the LGM. Among the 410 E. regnans individuals analysed, 31 haplotypes were identified. The statistical parsimony tree shows that haplotypes divided into two distinct groups corresponding to mainland Australia and Tasmania. The distribution of haplotypes across the range of E. regnans shows strong geographic patterns, with many populations and even certain regions in which a particular haplotype is fixed. Many locations had unique haplotypes, particularly those in East Gippsland in south-eastern mainland Australia, north-eastern Tasmania and south-eastern Tasmania. Higher haplotype diversity was found in putative refugia, and lower haplotype diversity in areas likely to have been recolonized since the LGM. The data are consistent with the long-term persistence of E. regnans in many regions and the recent recolonization of other regions, such as the Central Highlands of south-eastern mainland Australia. This suggests that, in spite of the narrow ecological tolerances of the species and the harsh environmental conditions during the LGM, E. regnans was able to persist locally or contracted to many near-coastal refugia, maintaining a diverse genetic structure.

Roonka is one of the most complete excavations of an Aboriginal burial ground in south-eastern Australia. The chronology of the site and the nature of its use have proven difficult to interpret. Previous dating and chronological interpretations of the site have emphasised a chronology of changing use and burial practices, but the nature of the site and the dates obtained do not clearly support these interpretations. We report on the direct dating of human bone from a further ten burials from the main excavation. In order to further investigate the cultural chronology set out by Pretty (1977), samples were selected to cover a range of burial types and preservation states. Comparison of these dates with the previous conventional dates and early AMS dates not only shows the impact of improving technology but demonstrates that multiple burial styles were in use contemporaneously. Moreover, the results suggest that use of the site may have been discontinuous. Consequently, interpretations that assume a chronological sequence for Roonka based on burial practice are not supported, while analyses based on a synchronic interpretation may ignore significant temporal change.

Aim: To relate genetic diversity to topographic features and to investigate genetic interactions between Eucalyptus species in a local centre of endemism and diversity in south-eastern Australia. Location: Grampian Ranges, Victoria, Australia. Methods: We documented chloroplast DNA (cpDNA) variation for a group of endemic Eucalyptus species (E. serraensis, E. verrucata and E. victoriana) that dominate rocky, high-elevation ridgelines of the Grampian Ranges and for one closely-related, widespread species (E. baxteri) occupying flanking slopes and valleys. We documented genetic patterns across the landscape using cpDNA microsatellites, and related them to topographic features (exposed west-facing versus protected east-facing slopes and valleys). We also determined the extent of local haplotype sharing between populations of endemic species and neighbouring E. baxteri downslope with cpDNA microsatellites, and haplotype sharing between the endemic group and more distantly related species (E. obliqua, E. pauciflora and E. willisii) with sequences of the J LA + chloroplast region. Results: We detected 26 cpDNA microsatellite haplotypes in a relatively small area of c. 20 km × 50 km. Populations of E. baxteri on east-facing slopes and valleys had greater cpDNA microsatellite diversity than E. baxteri and endemic species on exposed west-facing slopes. Endemic species frequently shared chloroplast haplotypes with E. baxteri downslope. Sharing of J LA + haplotypes with species outside the endemic group was mostly restricted to E. victoriana, which had cpDNA more similar to the species from other sections of Eucalyptus (E. obliqua, E. willisii and E. pauciflora). Main conclusions: Intensive sampling of related species on small isolated mountain ranges allowed us to relate genetic diversity to fine-scale habitats and to document extensive local haplotype sharing between species. This study contributes to a general understanding of the environmental conditions that enable plant population persistence by linking concentrations of genetic diversity to particular habitats.