The process of urbanisation results in dramatic landscape changes with long-lasting and sometimes irreversible consequences for the biota as urban sensitive species are eliminated. The Australian brush-turkey (Alectura lathami) is a recent urban colonist despite atypical traits for an urban adapter. Contrary to observed range declines and initial reports of decreased reproductive success in cities, Australian brush-turkeys have increased their range in urban areas.
AimsHistorical atlas and present citizen science data were used to examine the changing distribution of the Australian brush-turkey at continental and city scales, and the changing land use in urban areas occupied by the species. We assess which environmental and landscape features are driving observed distribution changes over time.
MethodsWe describe and map changes at the continental scale between 1839–2019. We then assessed colonisation of the cities of Brisbane and Sydney (located 900 km apart) over the period 1960–2019. At the city scale, we quantified the changing land use within Australian brush-turkey occupied areas over time using classification of satellite imagery.
Key resultsThe Australian brush-turkey’s geographical range has shifted over the last century, with the species receding from the western and southwestern parts of their range, while expanding in the northwest. Areas occupied in the cities of Brisbane and Sydney have expanded, with more recently occupied areas containing less vegetation and more developed land than previously occupied areas.
ConclusionsOur results confirm that Australian brush-turkeys are successfully colonising urban areas, including major cities, and are likely to continue moving into urban areas, despite declines elsewhere in their natural range. The species is not limited to suburbs with a high proportion of greenspace, as Australian brush-turkeys are increasingly occurring in highly developed areas with limited vegetation.
ImplicationsThis study highlights that species which were locally extirpated from urban areas, and thought to be unlikely candidates for recolonisation, can successfully occupy human modified habitats. Successful expansion is likely to be associated with key behavioural traits, urban greening, and legal protection from human persecution.
DNA recovered from predator faeces (scats) can be used to determine the presence of fauna and shed light on their life histories and inter-species interactions. DNA metabarcoding, which involves concurrent amplification and sequencing of DNA from multiple taxa, represents an important advance by enabling the simultaneous detection of multiple species from such samples. Although an attractive proposition, metabarcoding requires ‘universally’ applicable genetic markers that can discriminate among a broad range of taxa, while also targeting sequences that are sufficiently short to be amplified from degraded DNA.
AimsTo identify, evaluate, and test metabarcoding DNA markers suitable for the detection of marsupials and other Australian fauna from terrestrial predator scats found in nature.
MethodsWe apply a bioinformatic approach using publicly available DNA databases and a locally derived and marker-specific reference-DNA database to evaluate the diagnostic ability and likelihood of amplification of candidate metabarcoding markers for marsupials and other taxa that may be consumed by predators.
Key resultsWe identify two markers (12SV5 and 16SMam) that are suitable for use and successfully identify marsupial sequences at a high level of resolution. These markers work best in combination because they bring complementary levels of primer specificity and diagnostic ability in detecting multiple prey species as well as the predator. We also show that these samples work well in predator scats sampled from the wild in Tasmania.
ConclusionsThese markers provide a useful tool for surveying mammalian predators and their prey and could also be applied to eDNA analyses from other sample types. Improvements to the reference database and further development of markers targeting different taxonomic groups will improve the resolution and usefulness of this approach.
ImplicationsMetabarcoding of predator scats provides a potent approach to non-invasive wildlife survey that offers the opportunity for the detection of multiple species across all vertebrates.
Sus scrofa is a species that easily adapts to diverse environments and climatic zones. In urban and suburban spaces, its presence negatively impacts soil, crops, and animal production, posing health risks for other animals and even humans. Declared a national pest in Uruguay, it is one of the main predators of sheep. A deeper knowledge of its habitat, current distribution, and the environmental factors that influence its locations is required to develop an adequate programme to control its population.
AimsTo determine the spatial distribution of wild boars in Uruguay and its association with environmental factors concerning livestock production, on the basis of a survey administered to farmers.
MethodsThe survey was completed by 2360 farmers, gathering information on the presence of wild boars and other wildlife animals on their farms, methods used for wild boar control, economic damages caused by the species, number of sheep, and types of land-cover besides pastures (native woodlands, shelter forests, pine plantations, and eucalyptus plantations).
Key resultsFarms located in the Northeast region, with native woodlands and/or pine plantations, and larger than 500 ha were more likely to report the presence of wild boars. The presence of eucalyptus plantations did not affect the presence of wild boars in any region of the country. While the presence of sheep, free- ranging dogs, or wild boars on neighbouring farms affected the presence of wild boars, the existence of eucalyptus plantations showed no effect across any region of the country. On the other hand, the presence of wild boars increased in association with the presence of pampas foxes (Lycalopex gymnocercus).
ConclusionsThese results provide valuable information regarding the current distribution of an invasive exotic ungulate, and factors influencing the probability of reporting its presence.
ImplicationsThis information will serve as a starting point for future research analysing additional ecological and farm characteristics, as well as management strategies in sheep farms aimed at detecting, evading, dissuading and/or controlling this predatory species on the basis of its behaviour and environmental preferences.
Predator free havens are increasingly relied upon to preserve populations of imperilled species, yet despite their substantial cost, the success of these ventures is rarely critically evaluated.
AimsBased on 12 years of population monitoring data, we report on the translocation of woylies (Bettongia penicillata ogilbyi) to Perup Sanctuary, a 423 ha predator-free haven in the south west of Western Australia.
MethodsWe built spatially explicit capture–recapture models to estimate population density, population growth rates, and survivorship of woylies inside the sanctuary. Using these estimates, and additional demographic information, we aimed to show key drivers of population density, evaluate the establishment of the sanctuary population against predetermined translocation success criteria, and run simulations of different sampling designs to determine a robust sampling design for future monitoring of this population.
Key resultsThe population rapidly increased in the first 3 years (2010–2013), and then fluctuated around a density of ~0.9 woylies ha−1 before declining slightly in recent years to ~0.6 woylies ha−1. All translocation success criteria evaluated were met. The previous 3 months’ rainfall was a key driver of population density and body weight declined over time, indicating that the population may be regulated by food resources.
ConclusionsWoylies have established and persisted in Perup Sanctuary, and against the criteria, the translocation of woylies into Perup sanctuary is a success. Harvests from this population appear to have been sustainable. We discuss these findings in the context of the Perup Sanctuary, and recommend ongoing monitoring continue to ensure that the population remains viable and well managed.
ImplicationsWe describe important considerations for the supplementation and harvest of fenced populations, including: the source of animals (selecting free-living individuals over captive ones); the timing of release (releasing more individuals early on may improve establishment probabilities); and rates of harvest (<30% of adults harvested per generation seemeded to be sustainable for woylies in this case). The results from this study can inform the ongoing management of this and other havened populations, to ensure they continue to benefit mammal conservation.
Early surveillance and the detection of incursions of species of biosecurity concern are a crucial component of an effective biosecurity system. Citizen science represents an opportunity to engage communities in biosecurity, and to provide mechanisms for citizen scientists to contribute to both monitoring the spread of species already present in country, and reporting new incursions.
AimsTo present an example of how citizen science is being used for environmental biosecurity surveillance in Australia and showcase the value of large data services such as the Atlas of Living Australia (ALA), as a connector between citizen science and management.
MethodsWe detail how the alert email system was set up, using a bespoke solution implemented in the R programming language. The system works by querying the ALA database for species that match lists provided by management authorities. Alerts can be sent out at national, state/territory and local government scales, as well as defined spatial areas such as national park estates.
Key resultsTwelve months in, the top source for alerts comes from iNaturalist (a popular global biodiversity citizen-science platform), with other contributions from a set of biodiversity-reporting applications. Over a 12-month period, the alerts service has provided notifications for over 150 species, including the first public record of an invasive species in Australia.
ConclusionsSystems such as the Biosecurity Alerts Service, provide impact through the connection between communities and decision-making.
ImplicationsOur findings showed how the advancement of citizen science is interconnected with the advancement of research infrastructure and will ultimately lead to greater scientific and management value of citizen-science data.
Determining and quantifying habitat selection of endangered species in peri-urban environments assists planners and managers to develop strategies and alternative conservation measures in the face of urban expansion and development. Sloane’s Froglet (Crinia sloanei), listed nationally as endangered in Australia, is a little-known species distributed within peri-urban environments, where foundational ecological information and the development of adequate conservation responses has been lacking.
Aims(a) To determine a core calling period for Sloane’s Froglet and detection probabilities for occupancy surveys. (b) To understand and characterise the habitat that Sloane’s Froglet uses at the wetland and microhabitat scale.
MethodsWe used generalised linear modelling and the information-theoretic approach to model habitat preferences for this species at two scales: the waterbody scale, and the microhabitat scale. We quantified the habitat characteristics of waterbodies occupied by Sloane’s Froglet in winter, its peak breeding period, by measuring the biophysical characteristics of 54 occupied and 40 unoccupied waterbodies. The microhabitat and relative spatial positioning of Sloane’s Froglet within waterbodies was examined at 54 calling sites in an area of one m squared around individual male Sloane’s Froglets and 57 randomly selected unused sites. Wetlands were surveyed multiple times to determine detection probabilities.
Key resultsModel selection indicated that Sloane’s Froglet is 450 times more likely to occupy a waterbody when an adjacent ephemeral shallow overflow is present; and are more likely to be present when there is greater cover of small stem-diameter emergent vegetation and less bare ground on the bank. The microhabitat investigation of one m squared sites showed that Sloane’s Froglet’s calling sites are predominantly inundated, and at significantly shallower water depths, than unused sites. Sloane’s Froglet was found to always call from within the waterbody, distinguishing them from other sympatric Crinia species.
ConclusionsThe habitat characteristics detailed provide information necessary for the management of Sloane’s Froglet and its habitat.
ImplicationsHousing and industrial development is occurring rapidly in Sloane’s Froglet habitat. The information provided here can be used to refine local and state government planning and better design appropriate responses. Indeed, results from this study are currently being used by agencies and environmental consultants when developing conservation plans and in the design of stormwater retention ponds in rapidly urbanising environments.