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Halting the loss of biodiversity is a major challenge for humanity given the number of species at risk, the limited resources dedicated to conservation relative to levels of investment that are needed, and the impossibility of monitoring all threatened species, even in wealthy nations. Some of these challenges might be possibly addressed, in part, if conservation shortcuts could be found. These include the use of surrogates, proxies, and indicators in which easy to measure entities can accurately reflect the remainder of, for example, a particular assemblage of species.In the work reported here, we explored the indicator potential of particular species of arboreal marsupials in the tall, wet forests of south-eastern Australia. We did this through an empirical exploration of co-occurrence patterns using an analysis of a long-term dataset on arboreal marsupials that we gathered between 1997 and 2022 at 178 permanent field sites.Our analyses contained evidence of positive co-occurrence relationships between some pairs of species, but negative ones between others. In addition, relatively high levels of overall species richness in the arboreal marsupial assemblage were associated with four of the six species we analysed. We then tested the idea that these co-occurrence patterns were context-dependent. Although context dependence is a familiar issue in ecology, its importance for recognizing and understanding the limitations of surrogates like indicator species is often not well recognised. Indeed, we present evidence that some co-occurrence patterns varied across time and in response to key aspects of forest condition including the availability of nest sites in hollow-bearing trees, forest type, and stand age. We discuss these findings in relation to how context dependence can help us understand the applicability and limitations of ecological indicators. Our findings, based on long-term data, suggest that focused management efforts for a particular species as a “management indicator species” will not necessarily ensure positive outcomes for other species across all contexts. Therefore, targeted conservation efforts may be required for individual species, particularly species of conservation concern.

Long-term ecological monitoring is crucial to understanding the complex dynamics of ecosystems, communities, and populations. Despite this, monitoring data are lacking or rare for the vast majority of biodiversity. Here we report the results of 19 years (2003-2022) of continuous annual monitoring of reptile species at Booderee National Park (BNP) on the east coast of south-eastern Australia. We tested the effects of time, habitat type, fire, and climate on detections of five reptile species. Our study revealed declines in detections of two skink species over time (Lampropholis delicata and Ctenotus taeniolatus), which we suspect was partly driven by weather conditions influencing activity of these species. We also identified broad vegetation type associations for two congeneric species with L. delicata being associated with forested sites, and Lampropholis guichenoti associated with more shrubby sites. Our results also demonstrated a clear association between Cryptophis nigrescens and L. delicata and fire, with the probabilities of detection of both species decreasing with time since fire in the short term. At about the midway point of our study (in 2011), we were forced to make a change in the way our data were collected. The change heavily influenced our findings, and so breached the integrity of the time series in our dataset. We acknowledge that a simple but crucial step to mitigate this breach would have been to conduct calibration that allowed subsequent analysis to control for a change in field survey methodology. Whilst improvements in the effectiveness of field survey methods might be possible through new technologies, it is crucial to maintain the integrity of long-term datasets as data collection continues.

Abstract Fire is a key ecosystem process with more than half the world's land surface potentially subject to fire. A key aspect of fire ecology is the fire regime, with fire frequency an important component. Fire frequency appears to be increasing in some ecosystems, but decreasing in others. Such temporal and spatial variability in fire frequency highlights the importance of more effectively quantifying spatiotemporal changes in fire frequency for particular environments. We modeled changes in fire frequency over the past 40 years (1981–2020) in a 4.64 million ha area in Victoria, Australia. We quantified regional variation in the number of fires (hereafter termed fire frequency) during two 20‐year time periods (1981–2000 vs. 2001–2020), employing the Interim Biogeographic Regionalisation for Australia (IBRA), a standardized regionalization of Australia's terrestrial landscapes. We also quantified the climate and environmental factors influencing fire frequency in each IBRA subregion. Our empirical analyses revealed that fire frequency in Victoria was heterogeneous in both time and space. Wildfire frequency changed between 1981 and 2020, with the past 20 years (2001–2020) experiencing a substantially greater number of fires relative to the 20 years prior (1981–2000). Changes in fire frequency were not spatially uniform, with increases more pronounced in some IBRA subregions than others. Climate and topographic factors influenced the frequency of wildfires, but their effects manifested differently in different IBRA subregions. For example, fire frequency was associated with increasing rainfall deficit deviation in four IBRA subregions, but an opposite trend characterized two others. Associations between fire frequency and increasing temperature deviation also varied from negative to positive across subregions. We also found evidence of elevation, slope, and aspect effects, but these too varied between IBRA subregions. The complex spatiotemporal changes in fire frequency quantified in this study, and the complex between‐region differences in the factors associated with the number of fires, have major implications for biodiversity conservation, resource availability (e.g., timber yields), and ecosystem integrity. In ecosystems subjected to repeated fires at short intervals, new rapid detection and swift suppression technologies may be required to reduce the risks of ecosystem collapse as high‐severity wildfires increase in frequency.

Abstract Urbanization is increasing globally with wide‐ranging consequences for biodiversity and the ecological processes it performs. Yet knowledge of the range of ecological processes supported by biodiversity in urban environments, and the different taxa that perform these processes is poorly understood. We used a text‐analysis approach to identify the research trends and gaps in knowledge in the literature on ecological processes provided by animals in urban environments. We found a divide in urban ecological processes research that grouped studies into those with an explicit link to ecological processes and those that focused on biodiversity and made an implicit link to ecological processes. We also found that the dominant taxa in urban ecological processes research were insects, which has more than twice as many studies as birds or mammals, potentially due to their recognized and explicit link to key processes and services (e.g., pollination, pollution biomonitoring) and disservices (e.g., pests, disease transmission). We found a further split between terrestrial and aquatic studies, with urban aquatic studies also declining in relative prevalence over the last 20 yr. To consolidate and advance research on ecological processes in urban environments, we suggest it will be important to bridge the divide between studies on explicit services and others on more general biodiversity. This might be achieved by placing greater focus on the processes provided by non‐insect taxa, and by integrating aquatic and terrestrial perspectives.