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Predator diet can provide important data to inform management actions as well as an enhanced understanding of the fauna of a region. The diet of dingo (Canis lupus dingo), feral cat (Felis catus) and eastern barn owl (Tyto delicatula) were compared using scat, stomach and pellets from a significant conservation reserve in southwest Queensland. Dingo diet was dominated by macropods, while the diet of feral cat and barn owl was dominated by small mammals. We found no remains of threatened species but recommend continued monitoring of predator diet as a tool to assist management.

The birds of arid environments often exhibit nomadism, seasonal breeding and population fluctuations that respond to highly variable weather patterns. In this study we present data from a baseline bird survey in Bush Heritage Australia’s Pullen Pullen Reserve in south-western Queensland. We conducted seasonal surveys (October–November 2018, May 2019) in 40 sites representing Spinifex (Triodia spp.) grasslands, a complex of Mitchell Astrebla spp./chenopod grasslands and Georgina Gidgee Acacia georginae riparian woodlands, using a standardised 2-ha census. A total of 85 species was recorded in the standardised sites, as well as an additional 16 species recorded opportunistically. Twenty-six species (31%), many of which were nomadic, were recorded from only one of the surveys. Bird abundance and species richness were highest in the post-wet-season survey (May 2018), and there was strong variation in the composition of the bird species between the three habitats surveyed. These data provide a baseline to continue monitoring and to understand the resident and more peripatetic elements of this arid bird community, which should be surveyed regularly to investigate the role of changing management and the long-term influence of global environmental change.

Arid and desert landscapes are characterised as boom-bust systems, and sometimes its fauna can remain cryptic or hidden. This short paper reports the results of baseline monitoring of the terrestrial fauna in the Bush Heritage Pullen Pullen reserve in south-west Queensland, most notable for the presence of the night parrot Pezoporus occidentalis. We conducted two fauna surveys over 22 sites representing Spinifex grasslands, and Mitchell and Chenopod grassland habitats in 2018 and 2019, using pitfall, funnel and Elliott traps, and active searching. A total of eight mammal and 28 reptile species comprising 730 records were documented, as well as eight additional incidental species. Frequently recorded species were Ctentous lateralis, Ctenotus pantherinus, Gehyra versicolor, Tachyglossus aculeatus, Sminthopsis macroura, Pseudomys desertor. Fourteen of the species recorded were highly variable in abundance from one survey to the next. The fauna of the Spinifex grasslands, and Mitchell and Chenopod grassland sites was compositionally very different, and the extent of ground cover or Triodia in the surrounding landscape predicted the abundance of some mammals (i.e. Pseudomys desertor) and reptiles (Delma nasuta, Ctenotus pulchellus, Cyclodomorphus melanops). These data provide a baseline for future monitoring on this important reserve, and an opportunity to enhance or increase the survey scope via additional sites and a future more adaptive management and question-driven approach.

The eastern barn owl (Tyto delicatula) is a significant native predator of small mammals in Australia. Regurgitated pellets can provide important data on species presence, current or historical changes in mammal fauna over time, or data on cryptic or threatened species. We collected 125 pellets from Cravens Peak reserve, Simpson Desert, Queensland, and examined the contents, including changes in diet over time (using age of pellet as a proxy) and the relative importance of different prey. In total, 642 unique prey items were recorded, 92% of which were mammals. Small rodents were the dominant prey – Mus musculus and Pseudomys hermannsburgensis, and the presence of Notomys cf. fuscus, Pseudantechinus cf. mimulus and Dasycercus blythi were all significant, being range extensions. Such data add to more traditional or novel techniques to record community changes over time.

Nest predation is considered a major cause of population decline for the Endangered Alwal Psephotellus chrysopterygius (Golden-shouldered parrot) in Cape York Peninsula, Australia. Camera-traps wer...

Successful conservation of threatened species requires judicious allocation of limited resources. The threatened Black-throated Finch southern subspecies (Poephila cincta cincta), endemic to north-...

The Einasleigh Uplands bioregion of central north Queensland, Australia, harbours a unique suite of reptiles that have begun to receive significant attention in the last 20 years. This has resulted in a number of new reptile species being described, and recognition that others await description. We describe a new species of Lucasium Wermuth, 1965 from the western Einasleigh Uplands. Lucasium iris sp. nov. is genetically distinct and morphologically diagnosable from all congeners by its large size, long and narrow tail, nares in contact with rostral scale, homogeneous body scales, distinct vertebral stripe, and paired, enlarged, apical subdigital lamellae. It is known from low rocky hills in a localised area of the Gregory Range, has the most restricted known distribution of any Lucasium, and is the only Lucasium endemic to Queensland. The new species appears most closely related to L. steindachneri (Boulenger, 1885), based on mitochondrial DNA sequences, but has a colour-pattern more similar to L. immaculatum Storr, 1988. All three of these species occur in the Einasleigh Uplands, but only L. steindachneri is known to occur in sympatry with L. iris sp. nov. In addition to the description of the new species, we present records of Lucasium immaculatum from the Einasleigh Uplands, which represent a significant known range extension.

In addition to feeding on animal remains, many scavengers also function as predators. Carcasses may therefore affect local animal communities by attracting facultative scavengers and increasing predation risk for other species in the vicinity of the carcasses. This risk may be elevated in low productivity environments, especially where humans increase carcass production and where facultative scavengers include invasive species. In June and October 2018, we monitored experimentally placed red kangaroo (Osphranter rufus) carcasses and artificial bird nests in two different habitats in the Simpson Desert, Australia, to identify the nest predators attracted to the carcasses, and to determine how carcasses affect overall and predator-specific nest predation. We modelled our nests to approximate those of the ground nesting little buttonquail (Turnix velox) and the endangered night parrot (Pezoporus occidentalis). Native Corvus spp. and then invasive red foxes (Vulpes vulpes) were the top carcass visitors and nest egg predators. Carcass presence and open habitat increased overall nest predation and fewer artificial parrot nest eggs were depredated compared to those of quail. Open habitat and carcass presence only increased predator-specific nest predation by foxes, but corvid nest predation was highest in June 2018, and for the artificial quail nest types. Foxes were the main predator of eggs from night parrot nests. Our study shows that carcass provisioning by humans may have indirect, deleterious effects on ground nesting birds, and indicates that foxes might pose a greater threat to night parrot populations than previously recognised.

South-western Queensland supports a suite of threatened native species, including Night Parrots. We investigated why this species has persisted in the region and discovered low prevalence of the typical factors that are thought to explain fauna attrition elsewhere in central Australia. Foxes appear to be completely absent. Feral cats were recorded relatively infrequently and showed a significant preference for habitats less commonly used by Night Parrots, a partition that may be driven by the presence of dogs that were detected twice as frequently as cats. Our study area has had a long history of moderate grazing pressure, which is concentrated mostly in productive alluvial habitats. We detected very few herbivores, and dog scat analyses suggest that macropod populations are regulated by predation. Archival imagery shows that large fires are not a feature of this landscape, resulting in the long-term, stable availability of patchy Triodia habitats separated by natural no-fuel areas. Based on these empirical data, we postulate that low non-native predator pressure, long-term stable availability of Triodia cover and a productive landscape that has had only moderate grazing pressure are the interacting factors that may explain why Night Parrots have persisted in south-western Queensland. We present practical management actions that could enhance the suitability of this landscape for Night Parrots.

The critically endangered golden sun-moth Synemon plana occurs in urban fringe areas of southeastern Australia that are currently experiencing rapid and extensive development. The urban fringe is a complex and uncertain environment in which to manage threatened species with the intersection of fragmented natural habitats, built environments and human populations generating novel, poorly understood interactions. In this context, management frameworks must incorporate ecological processes as well as social considerations. Here, we explore how biodiversity sensitive urban design might improve the fate of the golden sun-moth, and threatened species generally, in urban fringe environments. We: (i) developed an expert-informed Bayesian Belief Network model that synthesizes the current understanding of key determinants of golden sun-moth population viability at sites experiencing urbanizing pressure; (ii) quantified the nature and strength of cause-effect relationships between these factors using expert knowledge; and (iii) used the model to assess expectations of moth population viability in response to different combinations of management actions. We predict that adult survival, bare ground cover and cover of resource plants are the most important variables affecting the viability of golden sun-moth populations. We also demonstrate the potential for biodiversity sensitive urban design as a complementary measure to conventional management for this species. Our findings highlight how expert knowledge may be a valuable component of conservation management, especially in addressing uncertainty around conservation decisions when empirical data are lacking, and how structured expert judgements become critical in supporting decisions that may help ameliorate extinction risks faced by threatened species in urban environments.

Summary The effective control of highly invasive weeds in Australia is an important conservation management action. In this study, we monitored the outcome of herbicide control on high-threat weeds in the wet forests of the Central Highlands of Victoria. Twenty-two control (no weed control) and 32 treatment (weed control) plots were surveyed annually over 24 months. Initial results show that weed cover and frequency decreased substantially in response to weed control; however, it is too early to determine the response of native species. We recommend that herbicide control and the associated monitoring programme be continued, and depending on the outcomes, data should be used to develop a more integrated management strategy.

Native grasslands, and the fauna that inhabit them, are globally some of the most threatened ecosystems and organisms. Knowledge of the relative importance of climate, landscape context and site-based resources for local insect populations is critical for the restoration and conservation of these communities. We investigated the site and landscape-scale best predictors of occurrence and abundance over three consecutive years of sampling, for the critically endangered golden sun moth Synemon plana in south-eastern Australia. We found eight vegetation factors to be significantly associated with golden sun moth occurrence using data from combined survey data and data for each year alone; we identified just three common factors from year to year. Modelling indicated that Austrostipa and Rytidosperma species richness was the most consistent parameter, but for each year alone, there was a combination of aspect, landscape position and Austrostipa and Rytidosperma species richness. Our study shows that environmental characteristics where golden sun moth occur are relatively predictable over multiple years. This information can be used to protect sites where monitoring of extant populations is yet to occur, predict the location of new populations in the region, and restore adjacent habitat that is suitable but degraded.

Following the establishment of a conservation reserve, changes in ground stratum vegetation following removal of cattle were examined in a northern Australian savanna over a 10-year period. The floristic composition of 40 vegetation plots in lowland savannas were surveyed shortly after acquisition of the property, and then surveyed twice in the following 10 years after cattle removal. Some notable ecosystem-transforming introduced species (weeds) such as Themeda quadrivalvis remained relatively stable, whereas the pasture legume Stylosanthes scabra increased in cover. The species richness of both native and introduced plants increased. Various plant functional groups changed in relative cover, with a decline in relatively unpalatable grasses and a corresponding increase in palatable grasses, responses that are consistent with recovery from grazing pressure. Our results show that removal of cattle in highly disturbed savanna ecosystems can have both positive and negative results for native ground stratum vegetation in the first decade of recovery.

In Australia, the role of noisy miners Manorina melanocephala in biotic homogenization of the avifauna has been well established in modified landscapes, and is listed as a threatening process under national conservation legislation. However, less is known about the effect of the congeneric and more widely distributed yellow-throated miner, M. flavigula. In this paper we investigate the relative roles of habitat loss and increased dominance by the yellow-throated miner in avian homogenization and species functional group decline. We examined bird community data collected from 368 woodland sites across three bioregions. For each site there was a local and a landscape scale measure of remnant vegetation cover. We used both multivariate and regression analysis to test the relative influence of yellow-throated miner abundance and vegetation on bird community composition. There was clear compositional change and homogenization of the avifauna where yellow-throated miners were present and vegetation cover was low. The abundance of 40 bird species was predicted by combinations of vegetation cover or yellow-throated miner abundance, and 31 of these regressions included the term yellow-throated miner. Of these, there was a negative relationship with 23 species, and 19 of these were insectivores or nectarivores. We postulate that the combination of clearing and yellow-throated miner abundance can interact to disrupt the ecological function of woodlands, by the depletion of insect- and nectar-feeding species and the disturbance to mixed feeding flocks. We propose future research objectives that include a continental-scale analysis of the determinants of yellow-throated miner overabundance, the numerical and geographical thresholds of their potential impacts, and the ecological consequences on both avifauna and the woodlands they inhabit.

Aim Strongly interacting species have disproportionately large ecological effects relative to their abundances or biomass. We previously developed two conceptual models that described how one such strong interactor, the Australian bird the noisy miner Manorina melanocephala : (1) establishes resident high-density and hyperaggressive colonies and (2) in doing so, affects other biota and ecosystem processes. Here, we evaluate parts of those models relating to noisy miner habitat preferences and effects on bird assemblages using data from across the geographical range of the miner. Location Eastern Australia. Methods Avian-assemblage data were compiled for 2 128 survey transects (distributed over > 1.3 × 10 6 km 2 ) and were linked to variables reflecting productivity, local habitat structure and landscape context. Predictors were chosen based on the models, although detailed data for some variables were unavailable at such large scales. We used hierarchical Bayesian models that included observation models to account for different survey effort coupled with potentially nonlinear, spatially-explicit process models. Conclusions Noisy miner densities increased with proximity to forest edges (higher densities on forest edges and open sites), in low rainfall areas, and in vegetation dominated by trees with blade-shaped rather than needle-shaped leaves. The presence of noisy miners at even relatively small densities (> 0.6 individuals ha −1 ) depressed both species richness and the abundances of smaller ( 63 g) bird species. In areas with higher mean rainfall, the associations between noisy miners and small- and large-bird species were more negative and less positive, respectively.

In this study we examined the spatial and temporal variation in a population of the critically endangered golden sun moth Synemon plana over four years in a conservation reserve in south-eastern Australia. We found golden sun moth spatial distribution and abundance dramatically declined from a peak in extent and abundance from 2008–2009 to 2011–2012 due to a shift from drought to above average rainfall. Autoregressive correlative models indicated that a northerly aspect and landscape position were key predictors of abundance over time, and golden sun moth distribution shifted from wet to dry locations in the landscape. We conclude that: our data provide a counterpoint to conclusions that golden sun moth has been known to persist in very small areas and suggest that distribution can change quite markedly (from large connected populations to small patches) at a local scale, and this will be due to dispersal and survivorship; the variability in the data may have implications for adequate detection of the species over time, especially when populations have contracted and species have a naturally restricted activity and breeding period; and long-term weather patterns and landscape configuration (aspect, wet or dry position) interact to significantly affect local distribution and abundance over time. This has implications for the species under global change; increased variability in rainfall, temperature, productivity and exotic pasture growth may all alter and interact to either reduce or enhance persistence of golden sun moth populations over time.

Aim We explored whether one native bird (the yellow-throated miner Manorina flavigula) greatly affected the composition of avifaunas in > 500,000 km2 in northern Australia. Location Rangelands of north-eastern Australia Methods Repeated avian surveys were conducted in 368 locations, for which in-site vegetation and landscape-contextual measurements were made. Hierarchical Bayesian models were used to determine whether avian assemblages were affected by variation in abundances of the yellow-throated miner. Results Variation in the abundances of the yellow-throated miner appeared to be governed largely by vegetation cover in surrounding landscapes. Summed abundances and richness of birds less massive than the yellow-throated miner ( 53 g) bird could not explain the patterns of variation in small-bodied species as well as the yellow-throated miner. There were no relationships between abundances and richness of larger species and abundances of the yellow-throated miner. Main conclusions The genus Manorina appears to be a competitive despot insofar as species smaller than it are concerned. There now is strong evidence that the local composition of avifaunas over much of a continent is controlled by the indiscriminate aggression of a colonial genus. Many of the existing ideas in community ecology that have been proffered for explaining the composition of vertebrate assemblages are inadequate for these assemblages given the profound influence of species of the genus Manorina. The mooted agricultural expansion of development in northern Australia almost certainly would favour the spread of the yellow-throated miner and probably will depress the occurrence and abundances of small-bodied bird species.

Pitfall trapping is a long established method for trapping terrestrial vertebrates globally. Many variations in bucket and drift fence arrays are used. Recent survey guidelines have been published for Queensland and the Northern Territory. In Queensland a “T” pattern is recommended, and we used data collected over five years to assess whether the use of this array, with the addition of a central bucket (Pit B), results in more captures, particularly in the central bucket. A total of 263 sites representing 1052 bucket samples were examined and the differences in capture abundance in bucket location was tested using analysis of variance. Pitfall bucket location significantly affected the captures of Dasyuridae, Muridae, Agamidae, Pygopodidae, Scincidae (P

The recent commentary by Woinarski (2014, Global Ecology and Biogeography, doi: 10.1111/geb.12165) disagreed with our conclusions on the correlates of decline in the marsupials of tropical Australia (Fisher et al., 2014, Global Ecology and Biogeography, 23, 181–190). We compared traits of species that were associated with range decline in southern and northern Australia. We found that habitat structure, climate and body size were correlated with range decline. In the north, declines of marsupials were most severe in savanna with moderate rainfall. In the south, the ranges of species in open habitat with very low rainfall have declined most. Also, the association between range decline and body mass differed between north and south: this is the main concern of Woinarski, who further disagreed with our choice of the Tropic of Capricorn as a boundary between north and south, our omission of rodents, how to treat timing of extinctions, and our inference that cats are major drivers of decline. We address these concerns in this response.

Aim A third of all modern (after 1500) mammal extinctions (24/77) are Australian species. These extinctions have been restricted to southern Australia, predominantly in species of ‘critical weight range’ (35–5500 g) in drier climate zones. Introduced red foxes (Vulpes vulpes) that prey on species in this range are often blamed. A new wave of declines is now affecting a globally significant proportion of marsupial species (19 species) in the fox-free northern tropics. We aim to test plausible causes of recent declines in range and determine if mechanisms differ between current tropical declines and past declines, which were in southern (nontropical) regions. Location Australian continent Methods We used multiple regression and random forest models to analyse traits that were associated with declines in species range, and compare variables associated with past extinctions in the southern zones with current tropical (northern) declines. Results The same two key variables, body mass and habitat structure, were associated with proportion-of-decline in range throughout the continent, but the form of relationships differs with latitude. In the south, medium-sized species in open habitats of lower rainfall were most likely to decline. In the tropics, small species that occupy open vegetation with moderate rainfall (savanna) are now experiencing the most severe declines. Throughout the continent, large-bodied species and those in structurally complex habitats (rainforest) are secure. Main conclusions Our results indicate that there is no mid-sized ‘critical weight range’ in the north. Because foxes are absent from the tropics, we suggest that northern Australian marsupial declines are associated with predation by feral cats (Felis catus) exacerbated by reduced ground level vegetation in non-rainforest habitats. To test this, we recommend experiments to remove cats from some locations where tropical mammals are threatened. Our results show that comparative analysis can help to diagnose potential causes of multi-species decline.

Ecological monitoring is important for tracking trends in species and ecosystems over time and is the basis of conservation planning and government policy. Given there are increasing constraints on funding opportunities for conservation research there need to be simple approaches to assess the costs and effectiveness of surveys that highlight where methods can be refocussed to address changing management aims. In this study we use data from a vertebrate fauna monitoring program to assess the extent to which the sampling has been effective in recording the total estimated vertebrate species richness, identify which classes, families or functional groups of birds, mammals and reptiles have been under sampled by existing methods and which of the survey methods used were most cost effective. We compiled data collected over six surveys conducted over five years on a conservation reserve in northern Australia as a case study. We used rarefaction curves to examine the rate of species accumulation and sampling adequacy for 15 fauna functional groups representing bird, mammal and reptile taxa. We also compared the cost effectiveness using the relative dollar cost for six survey methods including both observational (active search, bird counts) and trapping (cage, box, funnel and pitfall traps) techniques. In our case study, despite six repeated surveys, with a total estimated cost in excess of $500 000, sampling for six of the 15 targeted fauna groups was insufficient. Multiple survey methods are required to sample taxa such as reptiles and small mammals. Costs per methods were approximately equal when comparing different techniques such as pitfall, cage, Elliott and funnel traps. This study demonstrates that it is straightforward to use simple metrics of survey success to guide, refine and improve monitoring programs.

The tropical savanna of northern Australia is extensive and relatively homogenous compared to the open woodlands of temperate Australia. The avifauna of this biome is unevenly dispersed in the landscape. A standard count method for birds using a timed search along a 100-m transect with eight repeated counts per site over 4 days, has been used extensively over the past decade or more in these savannas, but its effectiveness has never been critically examined. We used data collected from across northern Queensland from 2004 to 2010, comprising 502 single-survey sites (each transect counted eight times) and 60 sites re-sampled four times from 2004 to 2008, to examine species records and accumulation of species over time with respect to time of day, increasing number of repeat counts(from 2 to 32 counts), species turnover, vegetation density effects and distance to first observation. Over 70% of the species in tropical savannas were easily observed and for 93% of the species vegetation structure did not alter detectability. Richness and abundance did not vary significantly across the day. We found that repeated sampling over multiple days, and at different times of the day, provides the best estimate of species richness at a site, and improved detectability.

The study of the ecology of species assemblages provides information on the function and resilience of ecosystems and helps predict the response of species to environmental change. Mixed-species flocks are a particular mode of avian assemblage and are suggested to have benefits for foraging and predator vigilance. In this study we examine for the first time the composition of mixed-species flocks in Australian savannas using data from 335 mixed-species flocks recorded across northern Queensland. A total of 122 species, both passerines and non-passerines, were observed in flocks. Individual flocks comprised 2–21 species and 2–237 individuals, with small, insectivorous birds dominant. Although flock composition was largely undifferentiated, six broad groups of mixed-species flocks were identified, their similarity driven by a few key species. Our study found that mixed-species flocks are a common component of the tropical savannas and are similar in individual bird abundance and richness compared with studies in other biomes. One important next step is to examine the relationship of mixed flocks to the entire species pool, and their ecological significance within tropical savannas.

The domestic cat Felis catus is distributed worldwide and has had a long historical relationship with humans. In some regions, such as Australia, it has become feral and a significant predator of native wildlife. A key component of quantifying and managing the conservation threat of introduced predators is an understanding of exactly what size and taxa of prey species are consumed, and whether there is a high degree of selectivity in the diet. A total of 169 cat stomachs were collected from north-eastern Australia, and their contents examined in relation to prey size, the body size of cats and selectivity using Jacob’s index. I found that F. catus contains a large amount of prey per cat (~200 g), mammals are the dominant prey item by mass, and feral cats predation was selective of small mammals (

Tropical savanna environments are characterised by annual and decadal patterns of resource change, which can affect the patterning of mobile fauna such as birds. In this study, we sampled 60 sites in northern Queensland, four times from 2004 to 2008. We investigated how the bird richness and abundance, and species turnover changed over the sample years and how this differed with vegetation structure. The mean abundance per site was highest in 2005 (92.1 ± 12.0 individuals ha–1) and lowest in 2008 (46.6 ± 3.3), whereas species richness per site was highest in 2004 (19.6 ± 0.9 species ha–1) and lowest again in 2008 (14.7 ± 0.8). Nine species were most abundant in 2004 coincident with extremely high rainfall preceding the survey in that year. Species turnover increased across all sites from 2004 to 2008 and the abundance of 13 species was best accounted for by differences in vegetation structure. Our study demonstrates that local bird communities in the semi-arid fringe of savannas can change rapidly, and mostly where vegetation is modified. This suggests that increased land-use and climate change in northern Australia could have significant effects on the avifauna over fairly short periods.

The introduction of domestic cattle into systems that have had little historical grazing by large herbivores, such as the case in Australia, can lead to both direct and indirect changes in native flora and fauna. In this study, we investigate the differences in native mammal abundance between pastoral land managed for cattle production and conservation land in Australian tropical savannas. We systematically sampled 68 sites for mammals in north-eastern Queensland representing the two land tenures, which represent land with introduced stock and native herbivores present, and land where only native herbivores occur. We recorded 17 species of mammals representing five families and two functional groups (small mammals and macropods). Generalized linear mixed effects models identified that there was a significant positive relationship between increasing total ground cover and small mammal abundance and also the abundance of two species, Pseudomys desertor and P. gracilicaudatus. We recorded a reduction in abundance on pastoral land for macropods and small mammals, and four species, M. robustus, M. rufus, Leggadina lakedownensis, P. gracilicaudatus. Total ground cover and perennial grass cover was lower on pastoral land. Small mammal abundance on pastoral land was less even with increasing ground cover. Our results suggest that on pastoral land, native mammal abundance is affected and this has some relationship to ground cover changes. We recognize that there are other confounding management differences between pastoral and conservation lands such fire use, dingo baiting, and the manner of weed invasion and control that could influence mammal pattern. We conclude that conservation strategies for mammals in Australia’s tropical savannas need to include a variety of land management schemes and tenures including land free from grazing by domestic livestock.

Overabundant native species can have a significant cascading effect on other components of wildlife, and those that deplete other species, often promoted by anthropogenic change to vegetation cover and habitat, are called reverse keystone species. Birds in the genus Manorina are widely reported as being such species, and in highly disturbed or fragmented environments, and some intact environments, noisy miners Manorina melanocephala can have a strong negative effect on small passerine species via hyper-aggressive mobbing. The tropical savannas of northern Australia consist of largely unmodified woodlands, and two species of Manorina occur naturally in this region: the noisy miner and the yellow-throated miner Manorina flavigula. Therefore, what effect do these species have on bird assemblage in predominantly continuous habitats, relative to other typical determinants of avifauna assemblage such as vegetation structure? We used data collected from bird surveys at 511 sites across northern Queensland (179 noisy miner M. melanocephala sites, 332 yellow-throated miner M. flavigula sites) between 1998 and 2010. We examined the variation in bird composition at each site due to increasing abundance of Manorina spp. using uni- and multivariate techniques. We found total bird richness was significantly lower in sites where noisy and yellow-throated miner abundances were highest, and passerine species seemed most affected. For species, 45 species varied significantly in abundance with increasing miner numbers, and the overall effect of yellow-throated miners on other birds seemed more pronounced. However, vegetation structure was generally an equal or more important predictor of avifauna richness and abundance. We conclude that despite the superficially intact nature of northern Australian woodlands, pastoral intensification or poor land management might create disturbances that facilitate increases in the abundance of Manorina, causing localized overabundance and a compounding negative effect on other native bird species.

This paper reports the results of dry and wet season systematic terrestrial vertebrate fauna surveys carried out on Blackbraes, a National Park in the Einasleigh Uplands bioregion, North Queensland. It quantifies, for the first time, the biodiversity values of the highest altitude upland area in the Australian tropical savanna. Nine species, including two mammals and seven reptiles, were recorded at the limits of their known range, or in seemingly disjunct populations. Patterns of fauna assemblage in relation to underlying geology and associated habitat variables were investigated and several strong relationships emerged. Temporal patterns in the observed fauna were investigated and 20 species (15 birds, 5 reptiles) were found to be more numerous in different seasons (wet and dry). The avifauna recorded was consistent with much of Australia's tropical savanna, but the reptile and mammal assemblages were distinct, rich and unusual, with exceptionally high abundances, particularly of some arboreal mammals. ...

An essential component of conservation science is repeated surveys over time to monitor species that might be responding to local factors, such as land management, or more broadly to global change. A systematic survey of the avifauna of Cape York Peninsula was conducted in the late 1990s and early 2000s providing an ideal basal dataset for measuring change in the avifauna. A subset (n >600) of these sites, primarily within savanna landscapes, was selected for re-survey in 2008 to investigate changes in bird communities on Cape York Peninsula. Changes in mean species richness varied across the study area (decreases in 59 grid cells and increases in 43) with no apparent pattern. Significant change in reporting rates was recorded in 30 species. Four sedentary and highly detectable species declined (Bar-shouldered Dove, Brown Treecreeper, Sulphur-crested Cockatoo and Pale-headed Rosella) and five increased (Peaceful Dove, Pheasant Coucal, Weebill, White-throated Honeyeater and Yellow Oriole). Habitat preference for the species that showed change remained relatively stable between the two survey periods. Some species that were recorded in very low numbers in the original survey and are conside red to be threatened (Brown Treecreeper, Black-faced Woodswallow) remained in very low numbers or decreased in our survey suggesting that there has been no regional recovery of these species. Long-term monitoring can describe important patterns of species change over time, though in the case of large, highly seasonal environments like the tropical savannas, signals of change may manifest over decades rather than annually.

2011 Australian Zoologist volume 35 (3) Knowledge of basic information like taxonomy, distribution and habitat preference for much of Australia’s amphibian and reptile fauna is still increasing. For example, regarding reptiles, Wilson and Swan 2008 state that “more than 20 species have been added to this revised edition, and many maps have been adjusted to accommodate range extensions” in the five years since the first edition (2003). Further descriptions have occurred since then (e.g. Hoskin and Higgie, 2008; Couper et al, 2008).

The domestic cat Felis catus has become a feral predator and conservation threat in many regions of the world. In the northern tropical savannas of Australia, there is limited data on feral cat diet, and there is evidence that some mammal populations in this region are starting to show signs of significant population decline. A total of 169 cat stomach samples were collected from north-eastern Australia from 1996 to 1998. Samples were collected from grassland and woodland habitats in winter and summer periods. A total of 106 unique prey types (grouped into 59 categories), representing 974 items, were recorded from all samples of which 8% were invertebrates, 9% amphibians, 41% reptiles, 20% birds, and 22% mammals. Relative significance of prey items was examined by calculating the Index of Relative Importance. Chi-square comparisons of frequency differences among habitat, season, and sex of cat were also undertaken. The most important prey items were grasshoppers (Orthoptera), centipedes (Chiloptera), dunnarts (Sminthopsis spp.), planigales (Planigale spp.), rabbits, quails (Turnix spp., Coturnix sp.), and geckos (Oedura spp., Gehyra spp.). Amphibians and invertebrates were more frequent in summer (wet season) samples, and mammals were more frequent in winter. Similarly, there were more amphibians in woodland samples and more invertebrates in grasslands. There was high dietary overlap and little difference in the diet of male versus female cats. Increasing cat predation in northern Australia may significantly affect the conservation of key groups already under decline (e.g., mammals) and careful innovative solutions to stem cat predation are needed.

This study examined patterns in the species richness and abundance of small non-volant mammals along a tropical altitudinal gradient in north-eastern Australia. We investigated whether a mid-altitudinal peak in diversity was apparent, and if it occurred, whether it was determined by particular environmental conditions. We sampled a small-mammal assemblage at 17 sites distributed along an altitude-environmental gradient from savanna (350 m) to rain-forest vegetation (1000 m). Over four separate occasions (5100 trap-nights) we recorded 17 species of mammal with 416 captures. A positive non-linear relationship between altitude and mammal species richness and abundance was observed, peaking at the 800–900 m range. Many species were distributed across a range of altitudes, while others were strongly associated with particular habitat conditions. There was a distinct reduction in abundance and species richness at low altitudes associated with the less complex vegetation, lower productivity and possible anthropogenic effects. Key findings were: that small-mammal richness peaked towards the summit of the gradient and not at one-half the maximum altitude predicted by the mid-domain effect; contrasting conditions and greatest vegetation juxtaposition had the greatest influence on the patterns recorded; and that local idiosyncratic influences such as habitat factors, land management and historical biogeography are significant.

We examined the spatial fidelity in the pattern in species richness, abundance and composition of ants, birds, mammals and reptiles in a Eucalyptus vegetation type in Australian tropical savanna woodland. We sampled 32 sites representing intact (uncleared) vegetation, and three treatments of different clearing age (2, 12 and 18 years). We investigated whether each fauna taxon could act a surrogate for pattern in the other, and whether they responded in parallel to time since clearing. Reptiles and mammals were combined into a single group. The correlation between taxa was low for abundance (the best being between rept/mamm and ant abundance R = 0.34) and moderate for species richness (varied from 0.36 to 0.44). Mantel tests identified a moderately strong relationship between bird and rept/mamm composition (R = 0.48). Recent clearing (2–12 years) depleted both abundance and species richness of the vertebrate fauna, whereas ant abundance spiked. Ant species richness was consistent over time since clearing. ANOSIM revealed that clearing age was a strong a priori predictor of birds and rept/mamm composition (Global R = 0.48, 0.65, respectively), whereas it was not for ants (Global R = 0.20). Pair-wise comparisons suggested that for birds, rept/mamm, there was consistent changes in composition from intact woodlands to different aged clearing. This was not the case for ants; most distinct variation in composition occurred between treatments of increasing in clearing age (2–18 years R = 0.69, 12–18 years R = 0.65). The results of this study do not support the use of ants as a surrogate of vertebrates at a local scale in a cleared and intact vegetation mosaic. We acknowledge that identification of universal surrogates and indicators are difficult to find, but funding and political expediency that demand rapid solutions to conservation planning necessitate continued investigation of the merits of using surrogate species.

Australia has a large suite of mangrove dependent bird species. Apart from detailed work in the Northern Territory, there has been little additional survey of bird pattern in this vegetation type. The abundance and habitat preference of birds were surveyed in six vegetation types on Trinity Inlet, Cairns. Birds were counted on four occasions from 1998-1999, and forty-seven bird species, representing nine foraging guilds, were recorded. Vegetation type was a strong discriminator of bird composition. I recorded a number of mangrove-obligate species (e.g. Collared Kingfisher, Mangrove Robin, Mangrove Gerygone) more abundantly, or restricted to mangrove vegetation, and a further suite of species that were mangrove-facultative (e.g. Shining Flycatcher, Rufous Fantail, Helmeted Friarbird, Spangled Drongo, Brown Honeyeater, Dusky Honeyeater). Many of the species recorded are more typically associated with rainforest, open woodlands and forests (e.g. Spectacled Monarch, Rose-crowned Fruit-dove, Variegated Fairy-w...

We studied the response of vegetation and vertebrate assemblages to fire and grazing, and their interacting effects, in Eucalyptus woodland in north-eastern Australia. In this vegetation type, many pastures remain free of cattle grazing due to the occurrence of a native shrub poisonous to livestock. Vegetation (floristic data and 22 habitat variables) and vertebrate fauna (birds, mammals, reptiles) were sampled in 29 standardized 50 × 50-m quadrats in the 2001 wet season, representing four treatments: sites burnt recently (within 2 y) and grazed by cattle (4–8 ha per livestock unit); sites unburnt (last burnt >2 y ago) and grazed; sites burnt recently and ungrazed; and unburnt and ungrazed sites. Fire and grazing had a significant influence on vegetation: both grazing and fire reduced ground cover (fire in grazed sites 51–23%, fire in ungrazed sites 68–39%) and increased the cover of forbs (8% in burnt and grazed sites, 3% if ungrazed) and tussock grasses (20% in grazed and unburnt sites and 5% when ungrazed). Grazing caused a shift in floristic composition from the perennial hummock grass Trioda pungens to tussock grasses (e.g. Aristida spp., Enneapogon spp.), forbs (e.g. Phyllanthus spp.) and shrubs (e.g. Acacia spp.). Of the vertebrate groups, birds responded more to fire effects (9 species), reptiles to grazing effects (6 species) and mammals to the interaction (2 species). Species reacted to increases in bare ground (e.g. crested pigeon Ocyphaps lophotes, hooded robin Melanodryas cucullatus, Ctenophorus nuchalis) and to the dominant ground cover (e.g. Ctenotus pantherinus) or change in vegetation architecture (e.g. singing honeyeater Lichenostomus virescens, variegated fairy-wren Malurus lamberti). The clearest example of an interacting effect was the cycle of complementary dominance between the rodents Pseudomys delicatulus and P. desertor, the latter's post-fire recovery becoming more muted in sites where cattle grazed (modelled time for population recovery twice as long as in ungrazed sites).

Australia has experienced dramatic declines and extinctions of its native rodent species over the last 200 years, particularly in southern Australia. In the tropical savanna of northern Australia significant declines have occurred only in recent decades. The later onset of these declines suggests that the causes may differ from earlier declines in the south. We examine potential regional effects (northern versus southern Australia) on biological and ecological correlates of range decline in Australian rodents. We demonstrate that rodent declines have been greater in the south than in the tropical north, are strongly influenced by phylogeny, and are consistently greater for species inhabiting relatively open or sparsely vegetated habitat. Unlike in marsupials, where some species have much larger body size than rodents, body mass was not an important predictor of decline in rodents. All Australian rodent species are within the prey-size range of cats (throughout the continent) and red foxes (in the south). Contrary to the hypothesis that mammal declines are related directly to ecosystem productivity (annual rainfall), our results are consistent with the hypothesis that disturbances such as fire and grazing, which occur in non-rainforest habitats and remove cover used by rodents for shelter, nesting and foraging, increase predation risk. We agree with calls to introduce conservation management that limits the size and intensity of fires, increases fire patchiness and reduces grazing impacts at ecological scales appropriate for rodents. Controlling feral predators, even creating predator-free reserves in relatively sparsely-vegetated habitats, is urgently required to ensure the survival of rodent species, particularly in northern Australia where declines are not yet as severe as those in the south.

The Lakeland Downs Mouse Leggadina lakedownensis is one of two species of short-tailed mice endemic to Australia. In Queensland there have been only very few recent sightings, and the species was thought to be restricted to parts of northern Cape York Peninsula. Five new localities are reported, including range extensions to central Queensland. Habitat for the species varies from chenopod to spinifex grasslands, Melaleuca woodlands and open savanna Eucalyptus woodlands, ranging from tropical coastal esplanades to sub-tropical rangelands. Trap localities encompass altitude from sea level to over 1000 m, and annual rainfall from 600-1800 mm, but are unified by a dense ground cover and waterlogging red or white sandy clays. Some potential threats to these rodent's populations are postulated including loss of ground cover and clearing of habitat in coastal regions. Despite contentions of a plaguing species, this rodent was rarely encountered in areas extensive sampled within its range. Notwithstanding the spa...

The Chestnut Dunnart Sminthopsis archeri is a rarely encountered dasyurid. Only a handful of records is known from the tropical savannas of northern Cape York Peninsula and southern Papua New Guinea (Van Dyck 1986; Flannery 1995). Within Australia the species was previously considered endemic to Cape York Peninsula (Winter and Lethbridge 1995). Despite almost two decades of search effort throughout Cape York Peninsula very few recent records have surfaced (Winter and Atherton 1985; Woolley 1993; see review of unpublished data in Winter and Lethbridge 1995). The last documented capture of S. archeri was in 1993 in the Iron Range area (Leung et al. 1994). Sminthopsis archeri has been previously captured in tall Eucalyptus tetrodonta, Corymbia nesophila, Erythrophleum chlorostachys woodlands on red earth soils, though it is also known from tall heathlands (Leung et al. 1994; Flannery 1995; Van Dyck 1995; Winter and Lethbridge 1995). Data regarding biology, distribution and status are correspondingly scant and restricted to locality descriptions, breeding and morphometric features of captured animals (Van Dyck 1995). Sminthopsis archeri is classified as rare in Queensland (Queensland Government 1997) and "data deficient" in Commonwealth assessments (Maxwell et al. 1996). This note reports an exceptional new locality for the species, representing a significant range extension.

The patterns of composition and distribution of vertebrate fauna in Queensland's tropical savannas are poorly known. The sandstone landscapes of White Mountains National Park are considered to be significant for fauna given its geographical position on the Great Dividing Range. A survey at White Mountains National Park was undertaken in order to determine the species present, and place them in the context of the assemblages recorded within the Desert Uplands Bioregion. Standardised trapping and incidental data collection techniques were used and a total of 122 vertebrate fauna species (53 being new to the park) were identified. The fauna assemblage contains a mix of vertebrates with some affiliation to north-eastern Queensland tropical savannas (e.g. Anomalopus gowi, Uperoleia lithomoda, Chaerephon jobensis), more mesic east coastal environments (e.g. Glaphyromorphus punctulatus, Planigale maculata, Rattus sordidus) and species distributed generally within and west of the Desert Uplands (e.g. Pseudomys desertor, Ctenotus rosarium, Gehyra variegata, Lerista wilkinsi).

[Extract] The Sandy Inland Mouse Pseudomys hermannsburgensis and the Delicate Mouse P. delicatulus are two closely allied members of the largest genus of Australian rodents (Watts and Aslin 1981). Currently 22 species are recognised in the genus Pseudomys (Cole and Woinarski in press), though the taxonomy of this large group has variably been considered "a repository for species hard to classify" (Watts and Aslin 1981). Taxonomic reassessment of the group is ongoing (Breed and Aplin 1995; Breed 1996; F. Ford, pers. comm, 2002. James Cook University), Pseudomys hermannsburgensis and P. delicatulus occur widely in Australia in sparsely grassed open woodlands, shrublands. Triodia grasslands and sand-plains. with P. hermannsburgensis more typical in treeless environments. Both are small to intenmediate sized (6-18 g. 55-90 mm) burrowing rodents, P. hermannsburgensis being slightly larger (Cole and Woinarski in press), Pseudomys delicatulus is widely distributed in eastern Queensland. and though P. hermannsburgensis is widespread in central Australia, it has only recently been confirmed as occurring in Queensland, despite long-held expectations of its presence (Covacevich and Easton 1974). Specimens collected in 1936 near Longreach and identified as P. minnie f1avescens (P. australis) have been recently reassigned as P. hermannsburgensis (S. Van Dyck. pers, comm, 2001. Queensland Museum) and the species has been captured frequently in long-term studies in southwest Queensland (Murray et al. 1999; Dickman et al. 1999). The two species were considered to be mutually exclusive in distribution, with P. delicatulus noted to have an almost perfect Torresian occurrence (Braithwaite and Covacevich 1995). with P. hermannsburgensis Eyrean by default. They are morphologically similar. and considered difficult to distinguish on external characteristics (Cooper 1993). Some workers have suggested distribution alone as an appropriate surrogate for identification (Covacevich and Easton 1974; Watts and Aslin 1981), Both species derived from a common ancestral Pseudomys form entering from New Guinea between 5-lO million years ago, with the subsequent evolution of P. hermannsburgensis into an inland species during a period of Pleistocene aridity and divergence (Baverstock 1982). Pseudomys delicatulus, P. novachollandiac and P. hermannsburgensis are all closely related (Baverstock et al. 1981). Despite earlier contentions of the exclusive distribution patterns of these two species, evidence exists for sympatry between P. hermannsburgensis and P. delicatulus in Western Australia (How et al. 1991) and the Northern Territory (J. Cole pers. comm. 2002, Northern Territory Department of Infrastructure, Planning and Environment). In Western Australia, both were trapped together in three sites at the Abydos-Woodstock Reserve, in very low open Eucalyptus and Acacia woodland, with Triodia spp. ground cover and sandy soils (How et al. 1991). In the Northern Territory distributions overlap in a band about 180 km wide. They are sympatric in the Mitchell Grass Downs Bioregion (Astrebla pectinata grasslands), and within 5 km of each other in the Gulf Fall Uplands Bioregion (Eucalytus leucophloia low open woodland with Trioda sp.) and in the Tanami Bioregion (mixed Triodia/Plectrachne spp. grasslands) (J. Cole pers. comm. 2002, Northern Territory Department of Infrastructure, Planning and Environment). This note reports on the opportunistic capture of P. hermannsburgensis in Queensland, identifying an eastern range extension and possible areas of overlap with P. delicatulus.

The Spinifexbird Eremiornis carteri is an inland species exclusively associated with mature Triodia spp. grasslands. Despite its wide distribution throughout arid and semi-arid Australia, a history of range expansion and contraction, and concentration into a number of core population centres, the species is considered monotypic. Two disjunct eastern localities were recorded during a vertebrate fauna survey of the Desert Uplands Bioregion in central-north Queensland, both in mature Triodia longiceps grasslands. These localities are described and reasons for the Jack of speciation within this taxon are reviewed. Nomadism in response to fire and climate pressures, discrete habitat specificity and current land use patterns are discussed as possible causes of lack of morphological differentiation, though the possibility of cryptic genetic variation in sub-populations is canvassed.

The Julia Creek Dunnart Sminthopsis douglasi has had a reputation as one of the more cryptic and restricted of Australia's dasyurid marsupials, despite being also the largest member of its genus (Woolley 1995). Only four museum specimens existed prior to 1992, all derived from a small area of "Downs Country" between Richmond and Julia Creek (Woolley 1995). Woolley (1992) reported further S. douglasi localities and these extended the range beyond the previously identified maximum geographic distribution. She concluded that the range of the species was certainly much larger than identified, and that the small number of known specimens was a result of low sampling effort rather than a pattern of natural restriction. Sminthopsis douglasi is considered to be obligate in habitat to treeless or lightly timbered tussock grasslands on cracking clay soils associated with the Mitchell Grass Downs and parts of the Gulf Plains Bioregions in northern and western Queensland. Given that this vegetation within Queensland covers over 20 million hectares (Sattler and Williams 1999). one might safely expect a species with such a strong environmental association to be more widespread within regions of potential habitat, even if there was some degree of climatic restriction. Apart from habitat preference, the extant distribution and abundance of this species is thought to be primarily influenced by predation by feral cats and foxes, loss of adequate grass cover and disturbance to soil structure by hoofed stock (Maxwell et al. 1996). This note reports new locality data for S. douglas; collected during a large-scale inventory vertebrate fauna survey in the Desert Uplands Bioregion. Habitat data, distribution and possible implications for conservation status are discussed.

[Extract] Paradelma orienralis is a member of the monophyletic and endemic family of Australian lizards, the Pygopodidae (Kluge 1974). Until relatively recently P. orientalis was known only from a small number of scattered localities exclusively within the central and southem Brigalow Belt region, east of the Great Dividing Range in south-central Queensland (Wilson and Knowles 1988; Cogger et al. 1993). New populations are now known for the southern, eastern and western extremes of this bioregion (Schulz and Eyre 1997; Tremul 1999). The eponymous common name implies P. orientalis has a strong association with the Brigalow Belt and this is certainly its core distribution (Covacevich et al. 1998). Habitat is generically reported as woodland consisting of, or associated with, Brigalow Acacia harpophylla vegetation (Wilson and Knowles 1988; Cogger er al. 1993; Sattler and Williams 1999), though a range of other Eucalyptus woodland associations without Brigalow have been recorded (Shea 1987; Wilson and Knowles 1988; Schulz and Eyre 1997; Tremul 1999). Many of these have a dense sub-canopy of other rough-barked species such as Callitris columellaris, Allocasuarina luehmanni and Acacia falciformis (Schulz and Eyre 1997; Tremul 1999). The biology of the species is poorly known. It is known to be oviparous, laying two eggs (Greer 1989), and detailed observations of a population on Boyne Island indicate it clearly noctural, active in temperatures generally above 19°C, partly arboreal, and both a sap and invertebrate feeding species (Tremul 1999). Sap feeding is unreported for other Pygopodids (Tremul 1999), but has been observed for geckos (Couper et al. 1995). The Brigalow Belt is one of the most highly modified and poorly reserved bioregions in Queensland (Covacevich et al. 1998; Sattler and Williams 1999) and almost no baseline or detailed bioregional fauna survey was conducted in the Brigalow Belt prior to the onset of extensive land clearance schemes in the 1960's (Gordon 1984; Covacevich et al. 1998). Twenty-seven reptiles are considered restricted to, or significantly distributed within, this bioregion, eighteen being of conservation significance (Covacevich et al. 1998). Paradelma orientalis is listed as vulnerable in Queensland under the Nature Conservation Legislation Amendment Regulation (No. 2) 1997 and Action Plan for Australian Reptiles (Cogger et al. 1993), though its continued appearance in new locations caused some authors to consider its conservation status requiring further investigation (Schulz and Eyre 1997). Habitat modification and conversion of native woodland to pasture and agriculture is considered to have had a severe impact on the pre-European distribution and abundance of this species (Gordon 1984; Cogger et al. 1993; Covacevich et al. 1998). This note reports new locality data for P. orientalis collected incidentally during large-scale vertebrate fauna surveys in the Desert Uplands and Northern Brigalow Belt. Habitat data and implications for conservation status are discussed.

To investigate potential geographic variation in the echolocation calls of Gould's Wattled Bat Chalinolobus gouldii, descriptive call parameters were examined from five regions throughout Australia. Analysis of these parameters revealed a number of significant differences between the regions, especially in variables related to frequency. However, discriminant function analysis revealed extensive overlap in call parameters for the different regions. It can be concluded that, although there are differences in some parameters between regions, calls are similar overall in the five geographic regions investigated, and that the slight geographic variation which does occur does not confound the identification of C. gouldii.

The flute-nosed bat Murina florium is a poorly known species that was first discovered in Australia at Mt Baldy State Forest on the Atherton Tablelands in north-eastern Queensland in 198 1. Subsequently there have been few other documented records despite intensive harp trapping studies, with the species only recorded from an additional six localities up until December 1995. This study provides four new locality records for the species, including two records which extend the known southern range limits of M. florium by 150 km across the Herbert River discontinuity within the Wet Tropics bioregion. The broad habitat characteristics of all known localities for the species are reviewed and the paper presents the first account of this bat occurring in non-rainforest habitat Occurrence of M. florium in this habitat is discussed using current knowledge of roosting and ecomorphology characteristics. A predicted distribution of M. florium based on the I I locality records, is calculated using DOMAIN and 16 biophy...

This study examined diet composition and specialisation of the Striped Legless Lizard Delma Impar, a species of conservation significance in southeastern Australia. A small sample of 25 faecal pellets was collected opportunity during the course of fauna surveys in the Derrimut Grasslands Reserve, Victoria: Their contents were examined and the invertebrate remains identified to the level of order. Invertebrate prey availability was estimated using samples collected from pitfall traps and dielary specialization was calculated using Levins (1968) standardized measure 01 niche breadth A low measure was recorded (0.05-0.07) and mainly cricket. spider and noctuid moth were found in the faecal pellets. This suggests that the Striped Legless Lizard is probably a specialized arthropod feeder. However. The small faecal pellet sample size, potential biases in the measurement of prey availability and possible uneven prey availability due to palatability constraints, may have differentially Influenced this result. Sea...

In highly seasonal tropical environments, temporal changes in habitat and resources are a significant determinant of the spatial distribution of species. This study disentangles the effects of spatial and mid to long-term temporal heterogeneity in habitat on the diversity and abundance of savanna birds by testing four competing conceptual models of varying complexity. Focussing on sites in northeast Australia over a 20 year time period, we used ground cover and foliage projected cover surfaces derived from a time series of Landsat Thematic Mapper imagery, rainfall data and site-level vegetation surveys to derive measures of habitat structure at local (1–100 ha) and landscape (100–1000s ha) scales. We used generalised linear models and an information theoretic approach to test the independent effects of spatial and temporal influences on savanna bird diversity and the abundance of eight species with different life-history behaviours. Of four competing models defining influences on assemblages of savanna birds, the most parsimonious included temporal and spatial variability in vegetation cover and site-scale vegetation structure, suggesting savanna bird species respond to spatial and temporal habitat heterogeneity at both the broader landscape scale and at the fine-scale. The relative weight, strength and direction of the explanatory variables changed with each of the eight species, reflecting their different ecology and behavioural traits. This study demonstrates that variations in the spatial pattern of savanna vegetation over periods of 10 to 20 years at the local and landscape scale strongly affect bird diversity and abundance. Thus, it is essential to monitor and manage both spatial and temporal variability in avian habitat to achieve long-term biodiversity outcomes.

(1996). Bird Populations Density in Thinned, Unthinned and Old Lowland Regrowth Forest, East Gippsland, Victoria. Emu - Austral Ornithology: Vol. 96, No. 4, pp. 280-284.