Compounding and complementary carnivores: Australian bird species eaten by the introduced European red fox Vulpes vulpes and domestic cat Felis catus

Two introduced carnivores, the European red fox Vulpes vulpes and domestic cat Felis catus, have had extensive impacts on Australian biodiversity. In this study, we collate information on consumption of Australian birds by the fox, paralleling a recent study reporting on birds consumed by cats. We found records of consumption by foxes on 128 native bird species (18% of the non-vagrant bird fauna and 25% of those species within the fox’s range), a smaller tally than for cats (343 species, including 297 within the fox’s Australian range, a subset of that of the cat). Most (81%) bird species eaten by foxes are also eaten by cats, suggesting that predation impacts are compounded. As with consumption by cats, birds that nest or forage on the ground are most likely to be consumed by foxes. However, there is also some partitioning, with records of consumption by foxes but not cats for 25 bird species, indicating that impacts of the two predators may also be complementary. Bird species ≥3.4 kg were more likely to be eaten by foxes, and those <3.4 kg by cats. Our compilation provides an inventory and describes characteristics of Australian bird species known to be consumed by foxes, but we acknowledge that records of predation do not imply population-level impacts. Nonetheless, there is sufficient information from other studies to demonstrate that fox predation has significant impacts on the population viability of some Australian birds, especially larger birds, and those that nest or forage on the ground.

Genomic Characterisation of a Highly Divergent Siadenovirus (Psittacine Siadenovirus F) from the Critically Endangered Orange-Bellied Parrot (Neophema chrysogaster)

Siadenoviruses have been detected in wild and captive birds worldwide. Only nine siadenoviruses have been fully sequenced; however, partial sequences for 30 others, many of these from wild Australian birds, are also described. Some siadenoviruses, e.g., the turkey siadenovirus A, can cause disease; however, most cause subclinical infections. An example of a siadenovirus causing predominately subclinical infections is psittacine siadenovirus 2, proposed name psittacine siadenovirus F (PsSiAdV-F), which is enzootic in the captive breeding population of the critically endangered orange-bellied parrot (OBP, Neophema chrysogaster). Here, we have fully characterised PsSiAdV-F from an OBP. The PsSiAdV-F genome is 25,392 bp in length and contained 25 putative genes. The genome architecture of PsSiAdV-F exhibited characteristics similar to members within the genus Siadenovirus; however, the novel PsSiAdV-F genome was highly divergent, showing highest and lowest sequence similarity to skua siadenovirus A (57.1%) and psittacine siadenovirus D (31.1%), respectively. Subsequent phylogenetic analyses of the novel PsSiAdV-F genome positioned the virus into a phylogenetically distinct sub-clade with all other siadenoviruses and did not show any obvious close evolutionary relationship. Importantly, the resulted tress continually demonstrated that novel PsSiAdV-F evolved prior to all known members except the frog siadenovirus A in the evolution and possibly the ancestor of the avian siadenoviruses. To date, PsSiAdV-F has not been detected in wild parrots, so further studies screening PsSiAdV-F in wild Australian parrots and generating whole genome sequences of siadenoviruses of Australian native passerine species is recommended to fill the siadenovirus evolutionary gaps.

A local scale evaluation of spatial sampling bias in the Atlas of Australian Birds

ABSTRACTThe reliability of ‘citizen science’ datasets where volunteers are free to choose sampling locations is not clear. This study examined local (‘patch’) scale spatial sampling patterns in the Atlas of Australian Birds and then compared reporting rates, i.e. the proportion of sampling units in which a given species was present, from a sample of atlas points with those from a regular sample. Three sites that have been were surveyed sequentially between January–May 2017: Killawarra Forest, Victoria, Coolah Tops National Park and Pilliga Nature Reserve, New South Wales. Spatial bias in atlas sampling patterns was evident as clusters at tourist areas and special habitat features and linear patterns along roads and creek lines. Atlas samples overestimated reporting rates for species with spatial distributions that were concordant with those sampling patterns and vice versa. At least two-fold differences in atlas/regular sample reporting rate ratios were detected for between 13–15% of non-rare species (with reporting rates ≥ 0.08). Concerns are raised that spatial sampling bias is common in the atlas and affects a variety of species, that popular sites may not be representative of habitat patches and that a large proportion of surveys are being filtered out in data analyses.

The Bird Assemblage of the Darwin Region (Australia): What Is the Effect of Twenty Years of Increasing Urbanisation?

There has been considerable urban development in the Darwin region over the last twenty years; as for most fauna in Australia since colonisation, the potential effects to the bird assemblage were expected to be disastrous. To provide a broad overview of changes, bird survey data from 1998 and 2018 were extracted from BirdLife Australia’s ‘Atlas of Australian Birds’ database. A total of 165 species were categorised into primary food source feeding guilds and levels of food specialisation. This was integrated into ArcGIS along with land use change mapping from 1998 and 2018 to investigate its impact on bird assemblages. There was no significant change in overall species numbers when all sites were analysed. However, when sites were separated into those with increased urbanisation or decreased greenspace, several sites showed a significant change in the number of species. For the majority of species, analysis of primary food types found no difference in the proportion of species within the assemblages between 1998 and 2018, regardless of the level of urbanisation or greenspace; the exception being those species that primarily feed on insects, where the difference was just significant. An analysis using bird community data sorted into levels of food specialisation also found no difference between 1998 and 2018 despite habitat changes. These findings suggest that although there has been considerable urban development in the Darwin region, bird communities are remaining relatively stable.

Action Plan for Australian Birds 2020

The Action Plan for Australian Birds 2020 is the most comprehensive review of the status of Australia's avifauna ever attempted. The latest in a series of action plans for Australian birds that have been produced every decade since 1992, it is also the largest. The accounts in this plan have been authored by more than 300 of the most knowledgeable bird experts in the country, and feature far more detail than any of the earlier plans. This volume also includes accounts of over 60 taxa that are no longer considered threatened, mainly thanks to sustained conservation action over many decades. This extensive book covers key themes that have emerged in the last decade, including the increasing impact of climate change as a threatening process, most obviously in Queensland's tropical rainforests where many birds are being pushed up the mountains. However, the effects are also indirect, as happened in the catastrophic fires of 2019/20. Many of the newly listed birds are subspecies confined to Kangaroo Island, where fire destroyed over half the population. But there are good news stories too, especially on islands where there have been spectacular successes with predator control. Such uplifting results demonstrate that when action plans are followed by action on the ground, threatened species can indeed be recovered and threats alleviated.

Persistent spatial gaps in ornithological study in Australia, 1901–2011

At the continental scale, ecological research effort is not spatially uniform. We used a century-long bibliometric database of the journal Emu – Austral Ornithology to index the spatial patterns in bird research in Australia (from articles with explicit study locations). Studies have been concentrated in Tasmania and the southwest, southeast and coastal parts of the mainland. Large spatial gaps exist in ornithological study, which are similar to those identified by Arnold Robert McGill in his 1948 review paper ( McGill 1948 ). Pre-1948 only 9.4% of articles [n = 2,107] fell within the gaps mapped by McGill in 1948, indicating that his mapping was largely accurate. These gaps have largely persisted; only 11.2% of the 1,498 articles published since 1948 came from within those gaps. We present a complementary spatial gap analysis, which focuses on studies of areas with broadly similar biogeographies (Interim Biogeographical Regions of Australia (IBRAs)). Of 85 mainland IBRAs (of 89 defined), five have no bird studies from within them (368,380 km2; 4.9% of Australia), and 34 have less than 10 studies (3,335,498 km2; 43.9%). We intersect IBRAs with McGill's gaps and show that some IBRAs within McGill's gaps are now better-studied, but 64.8% of the area within the McGill gaps boundaries comprises IBRAs where there have been no post-1948 studies in Emu. We also present an updated map of key geographical gaps in the study of Australian birds, which apparently remain extensive 60 years after they were first identified.