Category Archives: Publications

Dietary variation of an endangered mycophagous mammal in novel and remnant habitats in a peri-urban landscape

Authors: Sarah J Maclagan, Terry Coates, Austin O’Malley, and Euan G Ritchie

Published in: Austral Ecology


Understanding how fundamental aspects of species’ ecology, such as diet, are affected in human‐dominated landscapes is vital for informing management and conserving biodiversity – particularly where species influence important ecosystem functions. Digging, mycophagous (‘fungus‐eating’) mammals play various such roles, including the dispersal of hypogeal (‘truffle‐like’) fungi.

The endangered, mycophagous southern brown bandicoot (Isoodon obesulus obesulus: Peramelidae) persists in a peri‐urban landscape south‐east of Melbourne, Australia, where it occupies both ‘novel’ habitats (linear strips of vegetation along roadsides, drains and railway lines) and ‘remnant’ habitats (larger blocks of native vegetation) within dedicated conservation areas. It remains unknown how bandicoot diet, including the diversity of hypogeal fungi, varies between these habitat types, yet this could have important conservation implications.

Our study aimed to (i) compare the diet of I. o. obesulus at novel and remnant sites; and (ii) attain knowledge of hypogeal fungal diversity in these different contexts. We collected 133 bandicoot scats over 23 months and examined both broad diet composition and diversity of fungi consumed.

Bandicoot diet differed between site types; in particular, ants were more prominent in scats from remnant sites, while millipedes and seeds were more prominent in scats from novel sites. All scats contained fungal spores, with hypogeal taxa comprising at least 35 of the 78 ‘morphotypes’ found at novel sites and 28 of the 59 detected at remnant sites. Fewer samples were collected at remnant sites, but they appeared to contain a greater richness of hypogeal fungi per scat. We did not detect any differences in fungal composition between site types. However, our sampling effort was insufficient to estimate true morphotype richness at either site type.

Our study highlights the adaptable generalist diet of the southern brown bandicoot, as well as the likely under‐appreciated diversity of hypogeal fungi that can occur in highly modified, novel ecosystems.

Maclagan SJ, Coates T, O’Malley A, Ritchie EG (2020) Dietary variation of an endangered mycophagous mammal in novel and remnant habitats in a peri‐urban landscape. Austral Ecology PDF DOI

A guide to ecosystem models and their environmental applications

Authors: William L Geary, Michael Bode, Tim S Doherty, Elizabeth A Fulton, Dale G Nimmo, Ayesha I T Tulloch, Vivitskaia J D Tulloch, and Euan G Ritchie

Published in: Nature Ecology & Evolution


Applied ecology has traditionally approached management problems through a simplified, single-species lens. Repeated failures of single-species management have led us to a new paradigm — managing at the ecosystem level. Ecosystem management involves a complex array of interacting organisms, processes and scientific disciplines. Accounting for interactions, feedback loops and dependencies between ecosystem components is therefore fundamental to understanding and managing ecosystems.

We provide an overview of the main types of ecosystem models and their uses, and discuss challenges related to modelling complex ecological systems. Existing modelling approaches typically attempt to do one or more of the following: describe and disentangle ecosystem components and interactions; make predictions about future ecosystem states; and inform decision making by comparing alternative strategies and identifying important uncertainties.

Modelling ecosystems is challenging, particularly when balancing the desire to represent many components of an ecosystem with the limitations of available data and the modelling objective. Explicitly considering different forms of uncertainty is therefore a primary concern.

We provide some recommended strategies (such as ensemble ecosystem models and multi-model approaches) to aid the explicit consideration of uncertainty while also meeting the challenges of modelling ecosystems.

Geary WL, Bode M, Doherty TS, Fulton EA, Nimmo DG, Tulloch AIT, Tulloch VJD, Ritchie EG (2020) A guide to ecosystem models and their environmental applications. Nature Ecology & Evolution PDF DOI

Consequences of information suppression in ecological and conservation sciences

Authors: Don A Driscoll, Georgia E Garrard, Alexander M Kusmanoff, Stephen Dovers, Martine Maron, Noel Preece, Robert L Pressey, and Euan G Ritchie

Published in: Conservation Letters


Suppressing expert knowledge can hide environmentally damaging practices and policies from public scrutiny.

We surveyed ecologists and conservation scientists from universities, government, and industry across Australia to understand the prevalence and consequences of suppressing science communication.

Government (34%) and industry (30%) respondents reported higher rates of undue interference by employers than did university respondents (5%). Internal communications (29%) and media (28%) were curtailed most, followed by journal articles (11%), and presentations (12%). When university and industry researchers avoided public commentary, this was mainly for fear of media misrepresentation, while government employees were most often constrained by senior management and workplace policy. One third of respondents reported personal suffering related to suppression, including job losses and deteriorating mental health.

Substantial reforms are needed, including to codes of practice, and governance of environmental assessments and research, so that scientific advice can be reported openly, in a timely manner and free from interference.

Driscoll DA, Garrard GE, Kusmanoff AM, Dovers S, Maron M, Preece N, Pressey RL, Ritchie EG (2020) Consequences of information suppression in ecological and conservation sciences. Conservation Letters PDF DOI

Identifying and prioritizing human behaviors that benefit biodiversity

Authors: Matthew J Selinske, Georgia E Garrard, Emily A Gregg, Alexander M Kusmanoff, Lindall R Kidd, Meghan T Cullen, Michelle Cooper, William L Geary, Melissa A Hatty, Fern Hames, Sarah Kneebone, Emily M McLeod, Euan G Ritchie, Zoe E Squires, Janelle Thomas, Madelaine A W Willcock, Sera Blair, and Sarah A Bekessy

Published in: Conservation Science and Practice


The conservation profession is increasingly seeking effective ways to reduce societal impact on biodiversity, including through targeted behavior change interventions. Multiple conservation behavior change programs exist, but there is also great uncertainty regarding which behaviors are most strategic to target.

Behavioral prioritization is a tool that has been used effectively to support behavior change decision‐making in other environmental disciplines and more recently for a small sub‐set of biodiversity behavior change challenges.

Here, we use behavioral prioritization to identify individual behaviors that could be modified to achieve biodiversity benefits in the state of Victoria, Australia. We use an adapted nominal group technique method to identify potential biodiversity behaviors and, for each behavior, estimate the corresponding plasticity (or capacity for change) and positive impact on biodiversity outcomes.

We elicited 27 behaviors that individuals could undertake to benefit or reduce their negative impact on biodiversity. This list was then used to prioritize 10 behaviors as determined by their likely effect(s) on biodiversity, plasticity, and current prevalence in Victoria. We take a first step in outlining a list of behaviors that can direct Victorian decision‐makers toward increasing positive and reducing negative impacts of society on biodiversity, guide motivated individuals to reduce their own biodiversity footprint, and more broadly, develop a behavior change research agenda for behaviors most likely to benefit biodiversity.

Selinske MJ, Garrard GE, Gregg EA, Kusmanoff AM, Kidd LR, Cullen MT, Cooper M, Geary WL, Hatty MA, Hames F, Kneebone S, McLeod EM, Ritchie EG, Squires ZE, Thomas J, Willcock MAW, Blair S, Bekessy SA (2020) Identifying and prioritizing human behaviors that benefit biodiversity. Conservation Science and Practice PDF DOI

Evaluation of camera placement for detection of free-ranging carnivores; implications for assessing population changes

Authors: Hayley M Geyle, Michael Stevens, Ryan Duffy, Leanne Greenwood, Dale G Nimmo, Derek Sandow, Ben Thomas, John White, and Euan G Ritchie

Published in: Ecological Solutions and Evidence


Introduced carnivores are often cryptic, making it difficult to quantify their presence in ecosystems, and assess how this varies in relation to management interventions. Survey design should thus seek to improve detectability and maximize statistical power to ensure sound inference regarding carnivore population trends. Roads may facilitate carnivore movements, possibly leading to high detectability. Therefore, targeting roads may improve inferences about carnivore populations.

We assessed our ability to monitor feral cats Felis catus and red foxes Vulpes vulpes on‐ and off‐road, with explicit consideration of the location of monitoring sites on our ability to detect population changes. We also assessed whether there was evidence of spatial or temporal interaction between these species that might influence their road‐use.

Surveys were conducted in a conservation reserve in south‐eastern Australia between 2016 and 2018. At each of 30 sites, we deployed two motion‐sensor cameras, one on‐road, and the other off‐road. Using occupancy models, we estimated cat and fox occupancy and detectability, and conducted a power analysis to assess our ability to detect declines in occupancy under three monitoring regimes (efforts targeted equally on‐ and off‐road, efforts targeted entirely off‐road and efforts targeted entirely on‐road).

On average, on‐road detectability was seven times higher for cats and three times higher for foxes. Targeting survey effort on‐road yielded the greatest power for detecting declines in both species, but our ability to detect smaller declines decreased with decreasing initial occupancy probability. No level of decline was detectable for cats when survey efforts were targeted off‐road, while only large declines (>50%) were detectable for foxes (assuming high initial occupancy probabilities). We found little evidence of spatial or temporal segregation, suggesting limited avoidance or suppression between the two species within this landscape.

Our results suggest that targeting monitoring on roads may be an effective approach for detecting declines in introduced carnivore populations, particularly following management intervention (e.g. lethal control), and in the face of resource limitations. We provide a framework that can help assist land managers to make informed decisions, which balance monitoring efforts and resource constraints with sufficient statistical power to assess management objectives.

Geyle HM, Stevens M, Duffy R, Greenwood L, Nimmo DG, Sandow D, Thomas B, White J, Ritchie EG (2020) Evaluation of camera placement for detection of free‐ranging carnivores; implications for assessing population changes. Ecological Solutions and Evidence PDF DOI

Run rabbit run: spotted-tailed quoll diet reveals invasive prey is top of the menu

Authors: Grant D Linley, Annette Rypalski, Georgeanna Story, and Euan G Ritchie

Published in: Australian Mammalogy


Information about the ecological functional roles of native predators may help inform the conservation of wildlife and pest management.

If predators show preferences for certain prey, such as invasive species, this could potentially be used as a conservation tool to help restore degraded (e.g. overgrazed) ecosystems via the reintroduction of native predators and suppression of exotic prey (e.g. introduced herbivores).

The diet of spotted-tailed quolls was studied in a fenced reserve in south-eastern Australia where native mammals have been reintroduced, foxes and cats removed, but invasive European rabbits still persist.

A total of 80 scats were collected over 12 months and analysis of macroscopic prey remains was conducted to determine diet.

Rabbits were by far the most commonly consumed prey species by volume (~76%) and frequency (~60%), followed by brushtail possums (~11% for both volume and frequency), and other small and medium-sized native mammals in much smaller amounts. Quoll scat analysis revealed 10 mammal species in total, eight of which were native. Bird, reptile and invertebrate remains were uncommon in quoll scats.

This suggests that spotted-tailed quolls may show a preference for preying on invasive European rabbits in certain contexts, and this could potentially be used as part of quoll reintroductions to aid rabbit population suppression and ecosystem restoration.

Linley GD, Rypalski A, Story G, Ritchie EG (2020) Run rabbit run: spotted-tailed quoll diet reveals invasive prey is top of the menu. Australian Mammalogy PDF DOI

Living with the enemy: a threatened prey species coexisting with feral cats on a fox-free island

Authors: Vivianna Miritis, Anthony R Rendall, Tim S Doherty, Amy L Coetsee, and Euan G Ritchie

Published in: Wildlife Research



Feral domestic cats (Felis catus) have contributed to substantial loss of Australian wildlife, particularly small- and medium-sized terrestrial mammals. However, mitigating cat impacts remains challenging.

Understanding the factors that facilitate coexistence between native prey and their alien predators could aid better pest management and conservation actions.


We estimated feral cat density, examined the impact of habitat cover on long-nosed potoroos (Potorous tridactylus tridactylus), and assessed the spatial and temporal interactions between cats and potoroos in the ‘Bluegums’ area of French Island, south-eastern Australia.

Materials and methods

We operated 31 camera stations across Bluegums for 99 consecutive nights in each of winter 2018 and summer 2018/19. We used a spatially explicit capture–recapture model to estimate cat density, and two-species single-season occupancy models to assess spatial co-occurrence of cats and potoroos.

We assessed the influence of vegetation cover and cat activity on potoroo activity by using a dynamic occupancy model. We also used image timestamps to describe and compare the temporal activities of the two species.

Key results

Bluegums had a density of 0.77 cats per km² across both seasons, although this is a conservative estimate because of the presence of unidentified cats.

Cats and long-nosed potoroos were detected at 94% and 77% of camera stations, respectively.

Long-nosed potoroo detectability was higher in denser vegetation and this pattern was stronger at sites with high cat activity.

Cats and potoroos overlapped in their temporal activity, but their peak activity times differed.


Feral cat density at Bluegums, French Island, is higher than has been reported for mainland Australian sites, but generally lower than in other islands.

Long-nosed potoroos were positively associated with cats, potentially indicating cats tracking potoroos as prey or other prey species that co-occur with potoroos.

Temporal activity of each species differed, and potoroos sought more complex habitat, highlighting possible mechanisms potoroos may use to reduce their predation risk when co-occurring with cats.


Our study highlighted how predator and prey spatial and temporal interactions, and habitat cover and complexity (ecological refuges), may influence the ability for native prey to coexist with invasive predators.

We encourage more consideration and investigation of these factors, with the aim of facilitating more native species to persist with invasive predators or be reintroduced outside of predator-free sanctuaries, exclosures and island safe havens.

Miritis V, Rendall AR, Doherty TS, Coetsee AL, Ritchie EG (2020) Living with the enemy: a threatened prey species coexisting with feral cats on a fox-free island. Wildlife Research PDF DOI

Moon phase and nocturnal activity of native Australian mammals

Authors: Grant D Linley, Yvette Pauligk, Courtney Marneweck, and Euan G Ritchie

Published in: Australian Mammology


Moon phase and variation in ambient light conditions can influence predator and prey behaviour. Nocturnal predators locate prey visually, and prey may adjust their activity to minimise their predation risk. Understanding how native mammals in Australia respond to varying phases of the moon and cloud cover (light) enhances knowledge of factors affecting species’ survival and inference regarding ecological and population survey data.

Over a two-year period within a fenced conservation reserve, in south-eastern Australia, with reintroduced native marsupial predator and prey species (eastern barred bandicoot, southern brown bandicoot, long-nosed potoroo, rufous bettong, Tasmanian pademelon, brush-tailed rock-wallaby, red-necked wallaby, eastern quoll, spotted-tailed quoll, and naturally occurring swamp wallaby, common brushtail possum, common ringtail possum), we conducted monthly spotlight surveys during different moon phases (full, half and new moon).

We found an interaction between cloud cover and moon phase, and an interaction of the two depending on the mammal size and class. Increased activity of prey species corresponded with periods of increasing cloud cover. Predators and medium-sized herbivores were more active during times of low illumination.

Our findings suggest that moon phase affects the nocturnal activity of mammal species and that, for prey species, there might be trade-offs between predation risk and foraging. Our findings have implications for: ecological survey design and interpretation of results for mammal populations across moon phases, understanding predator and prey behaviour and interactions in natural and modified (artificial lighting) ecosystems, and potential nocturnal niche partitioning of species.

Linley GD, Pauligk Y, Marneweck C, Ritchie EG (2020) Moon phase and nocturnal activity of native Australian mammals. Australian Mammalogy PDF DOI

On the right track: placement of camera traps on roads improves detection of predators and shows non-target impacts of feral cat baiting

Authors: Michael L Wysong, Gwenllian D Iacona, Leonie E Valentine, Keith Morris, and Euan G Ritchie

Published in: Wildlife Research



To understand the ecological consequences of predator management, reliable and accurate methods are needed to survey and detect predators and the species with which they interact.

Recently, poison baits have been developed specifically for lethal and broad-scale control of feral cats in Australia. However, the potential non-target effects of these baits on other predators, including native apex predators (dingoes), and, in turn, cascading effects on lower trophic levels (large herbivores), are poorly understood.


We examined the effect that variation in camera trapping-survey design has on detecting dingoes, feral cats and macropodids, and how different habitat types affect species occurrences. We then examined how a feral cat poison baiting event influences the occupancy of these sympatric species.


We deployed 80 remotely triggered camera traps over the 2,410-km² Matuwa Indigenous Protected Area, in the semiarid rangelands of Western Australia, and used single-season site-occupancy models to calculate detection probabilities and occupancy for our target species before and after baiting.

Key results

Cameras placed on roads were ~60 times more likely to detect dingoes and feral cats than were off-road cameras, whereas audio lures designed to attract feral cats had only a slight positive effect on detection for all target species.

Habitat was a significant factor affecting the occupancy of dingoes and macropodids, but not feral cats, with both species being positively associated with open woodlands.

Poison baiting to control feral cats did not significantly reduce their occupancy but did so for dingoes, whereas macropodid occupancy increased following baiting and reduced dingo occupancy.


Camera traps on roads greatly increase the detection probabilities for predators, whereas audio lures appear to add little or no value to increasing detection for any of the species we targeted.

Poison baiting of an invasive mesopredator appeared to negatively affect a non-target, native apex predator, and, in turn, may have resulted in increased activity of large herbivores.


Management and monitoring of predators must pay careful attention to survey design, and lethal control of invasive mesopredators should be approached cautiously so as to avoid potential unintended negative ecological consequences (apex-predator suppression and herbivore release).

Wysong ML, Iacona GD, Valentine LE, Morris K, Ritchie EG (2020) On the right track: placement of camera traps on roads improves detection of predators and shows non-target impacts of feral cat baiting. Wildlife Research PDF DOI

Space use and habitat selection of an invasive mesopredator and sympatric, native apex predator

Authors: Michael L Wysong, Bronwyn A Hradsky, Gwenllian D Iacona, Leonie E Valentine, Keith Morris, and Euan G Ritchie

Published in: Movement Ecology



Where mesopredators co-exist with dominant apex predators, an understanding of the factors that influence their habitat and space use can provide insights that help guide wildlife conservation and pest management actions.

A predator’s habitat use is defined by its home range, which is influenced by its selection or avoidance of habitat features and intra- and inter-specific interactions within the landscape. These are driven by both innate and learned behaviour, operating at different spatial scales.

We examined the seasonal home ranges and habitat selection of actively-managed populations of a native apex predator (dingo Canis dingo) and invasive mesopredator (feral cat Felis catus) in semi-arid Western Australia to better understanding their sympatric landscape use, potential interactions, and to help guide their management.


We used kernel density estimates to characterise the seasonal space use of dingoes and feral cats, investigate inter- and intra-species variation in their home range extent and composition, and examine second-order habitat selection for each predator. Further, we used discrete choice modelling and step selection functions to examine the difference in third-order habitat selection across several habitat features.


The seasonal home ranges of dingoes were on average 19.5 times larger than feral cats. Feral cat seasonal home ranges typically included a larger proportion of grasslands than expected relative to availability in the study site, indicating second-order habitat selection for grasslands.

In their fine-scale movements (third-order habitat selection), both predators selected for roads, hydrological features (seasonal intermittent streams, seasonal lakes and wetlands), and high vegetation cover. Dingoes also selected strongly for open woodlands, whereas feral cats used open woodlands and grasslands in proportion to availability.

Management recommendations

Based on these results, and in order to avoid unintended negative ecological consequences (e.g. mesopredator release) that may stem from non-selective predator management, we recommend that feral cat control focuses on techniques such as trapping and shooting that are specific to feral cats in areas where they overlap with apex predators (dingoes), and more general techniques such as poison baiting where they are segregated.

Wysong ML, Hradsky BA, Iacona GD, Valentine LE, Morris K, Ritchie EG (2020) Space use and habitat selection of an invasive mesopredator and sympatric, native apex predator. Movement Ecology PDF DOI

After the catastrophe: a blueprint for a conservation response to large-scale ecological disaster

Authors: Chris Dickman, Don Driscoll, Stephen Garnett, David Keith, Sarah Legge, David Lindenmayer, Martine Maron, April Reside, Euan Ritchie, James Watson, Brendan Wintle, and John Woinarski

The wildfires that afflicted Australia in the summer of 2019-2020 was ecological disaster at enormous scale, and without comparable precedent. With escalating global climate change, such large-scale ecological catastrophes are likely to become more widespread and frequent. Here, we describe a blueprint for conservation responses to these wildfires, to document the challenge and attempted solutions to this particular event and as a potential template for dealing with comparable future events.

The purpose of this report, published as part of the Threatened Species Recovery Hub, is to frame a comprehensive set of linked responses to large-scale impacts for conservation across immediate to longer time frames, in order to best achieve the recovery of affected species, ecosystems and ecological health.

Dickman C, Driscoll D, Garnett S, Keith D, Legge S, Lindenmayer D, Maron M, Reside A, Ritchie EG, Watson J, Wintle B, Woinarski J (2020) After the catastrophe: a blueprint for a conservation response to large-scale ecological disaster. Threatened Species Recovery Hub PDF LINK

Predator responses to fire: A global systematic review and meta‐analysis

Authors: William L Geary, Tim S Doherty, Dale G Nimmo, Ayesha I T Tulloch, and Euan G Ritchie

Published in: Journal of Animal Ecology


Knowledge of how disturbances such as fire shape habitat structure and composition, and affect animal interactions, is fundamental to ecology and ecosystem management. Predators also exert strong effects on ecological communities, through top‐down regulation of prey and competitors, which can result in trophic cascades. Despite their ubiquity, ecological importance and potential to interact with fire, our general understanding of how predators respond to fire remains poor, hampering ecosystem management.

To address this important knowledge gap, we conducted a systematic review and meta‐analysis of the effects of fire on terrestrial, vertebrate predators worldwide. We found 160 studies spanning 1978–2018. There were 36 studies with sufficient information for meta‐analysis, from which we extracted 96 effect sizes (Hedge’s g) for 67 predator species relating to changes in abundance indices, occupancy or resource selection in burned and unburned areas, or before and after fire.

Studies spanned geographic locations, taxonomic families, and study designs, but most were located in North America and Oceania (59% and 24%, respectively), and largely focussed on felids (24%) and canids (25%). Half (50%) of the studies reported responses to wildfire, and nearly one third concerned prescribed (management) fires.

There were no clear, general responses of predators to fire, nor relationships with geographic area, biome or life history traits (e.g. body mass, hunting strategy and diet). Responses varied considerably between species. Analysis of species for which at least three effect sizes had been reported in the literature revealed that red foxes (Vulpes vulpes) mostly responded positively to fire (e.g. higher abundance in burned compared to unburned areas) and eastern racers (Coluber constrictor) negatively, with variances overlapping zero only slightly for both species.

Our systematic review and meta‐analysis revealed strong variation in predator responses to fire, and major geographic and taxonomic knowledge gaps. Varied responses of predator species to fire likely depend on ecosystem context. Consistent reporting of ongoing monitoring and management experiments is required to improve understanding of the mechanisms driving predator responses to fire, and any broader effects (e.g. trophic interactions). The divergent responses of species in our study suggest that adaptive, context‐specific management of predator‐fire relationships is required.

Geary WL, Doherty TS, Nimmo DG, Tulloch AIT, Ritchie EG (2019) Predator responses to fire: A global systematic review and meta‐analysis. Journal of Animal Ecology PDF DOI 

Digging up the dirt: quantifying the effects on soil of a translocated ecosystem engineer

Authors: Lauren M Halstead, Duncan R Sutherland, Leonie E Valentine, Anthony R Rendall, Amy L Coetsee, and Euan G Ritchie

Published in: Austral Ecology


Digging mammals are often considered ecosystem engineers, as they affect important properties of soils and in turn nutrient exchange, vegetation dynamics and habitat quality. Returning such species, and their functions, to areas from where they have been extirpated could help restore degraded landscapes and is increasingly being trialled as a conservation tool.

Studies examining the effects of digging mammals have largely been from arid and semi‐arid environments, with little known about their impacts and importance in mesic systems. To address this knowledge gap, we investigated the ecological role of a recently introduced population of eastern barred bandicoots (Perameles gunnii) on Churchill Island, Victoria, south‐eastern Australia, from which all digging mammals have been lost.

We quantified the annual rate of soil turnover by estimating the number of foraging pits bandicoots created in 100‐m² plots over a 24‐hour period. Foraging pit counts could not be completed in each season, and the overall turnover estimate assumes that autumn/winter months represent turnover rates for the entire year; however, this is likely to fluctuate between seasons. Ten fresh and ten old pits were compared to paired undug control sites to quantify the effect soil disturbance had on soil hydrophobicity, moisture content and soil strength. Plots contained between zero and 64 new foraging pits each day. We estimated that an individual eastern barred bandicoot digs ~487 (95% CI = 416–526) small foraging pits per night, displacing ~13.15 kg (95% CI = 11.2–14.2 kg) of soil, equating to ~400 kg (95% CI = 341–431 kg) of soil in a winter month. Foraging pits were associated with decreased soil compaction and increased soil moisture along the foraging pit profile.

Eastern barred bandicoots likely play an important role in ecosystems through their effects on soil, which adds to an increasing body of knowledge suggesting restoration of ecosystems, via the return of ecosystem engineers and their functions, holds much promise for conserving biodiversity and ecological function.

Halstead LM, Sutherland DR, Valentine LE, Rendall AR, Coetsee AL, Ritchie EG (2019) Digging up the dirt: Quantifying the effects on soil of a translocated ecosystem engineer. Austral Ecology PDF DOI

Constraints on vertebrate range size predict extinction risk

Authors: Thomas M Newsome, Christopher Wolf, Dale G Nimmo, R Keller Kopf, Euan G Ritchie, Felisa A Smith, and William J Ripple

Published in: Global Ecology and Biogeography


Aim: The only factor in the fossil record that consistently buffers against extinction risk is large geographical range. We ask whether extant vertebrate species with the smallest geographical range for their body size have a higher extinction risk, and thus whether the lower bound of the modern range–body size relationship could serve as an effective conservation prioritization tool.

Location: Global in scope.

Time period: Modern.

Major taxa studied: Six classes of vertebrates.

Methods: We compiled a database of geographical range, body size and extinction risk for six vertebrate classes (n = 26,076). We characterized the shape of the relationship between geographical range and body size for each class, using 90% and 10% quantile regression to describe the upper and lower bounds, respectively. We then evaluated the degree of extinction vulnerability of species at the lower bound of the regression using generalized linear mixed models. All analyses accounted for phylogenetic dependence between related species.

Results: The relationships between species ranges and body sizes were generally positive at both the upper and the lower bounds, and segmented (nonlinear) relationships were common. Despite this variability, species near the lower boundary of the relationship were more often in higher extinction risk categories, and this remained true when the role of range size in the International Union for Conservation of Nature Red Listing criteria was accounted for.

Main conclusions: Variability in the upper and lower bounds of the range–body size relationship suggests that some classes of vertebrates exhibit combinations of ranges and body sizes that might not reflect historical patterns. Nonetheless, the range–body size relationship remains a reliable and useful predictor of extinction risk, more so than range size does alone. The range–body size relationship could therefore be used to track the trajectories of species towards or away from an extinction threshold and allow the tracking of how different human activities alter the range–body size relationship.

Newsome TM, Wolf C, Nimmo DG, Kopf RK, Ritchie EG, Smith FA, Ripple WJ (2019) Constraints on vertebrate range size predict extinction risk, Global Ecology and Biogeography PDF DOI

Topographic ruggedness and rainfall mediate geographic range contraction of a threatened marsupial predator

Authors: Harry A Moore, Judy A Dunlop, Leonie E Valentine, John C Z Woinarski, Euan G Ritchie, David M Watson, and Dale G Nimmo

Published in: Diversity and Distributions


Aim: Species range contractions are increasingly common globally. The niche reduction hypothesis posits that geographic range contractions are often patterned across space owing to heterogeneity in threat impacts and tolerance. We applied the niche reduction hypothesis to the decline of a threatened marsupial predator across northern Australia, the northern quoll (Dasyurus hallucatus).

Location: Northern Australia.

Methods: We assembled a database containing 3,178 historic and contemporary records for northern quolls across the extent of their distribution dating between 1778 and 2019. Based on these records, we estimated changes in the geographic range of the northern quoll using α‐hulls across four main populations. We then examined how range contractions related to factors likely to mediate the exposure, susceptibility, or tolerance of northern quolls to threats.

Result: The extent of range contractions showed an east–west gradient, most likely reflecting the timing of spread of introduced cane toads (Rhinella marina). There were clear changes in environmental characteristics within the contemporary compared to the historic geographic range, with the most substantial occurring in populations that have suffered the greatest range contractions. The contemporary range is comprised of higher quality habitats (measured using environmental niche models), characterized by higher topographical ruggedness and annual rainfall, and reduced distance to water, compared to the historic range.

Main conclusions: Changes to range and niche likely reflect the capacity of complex habitats to ameliorate threats (namely predation and altered fire regimes), and access to resources that increase threat tolerance. This study highlights the multivariate nature of ecological refuges and the importance of high‐quality habitats for the persistence of species exposed to multiple threats. Our methods provide a useful framework which can be applied across taxa in providing valuable insight to management.

Moore HA, Dunlop JA, Valentine LE, Woinarski JCZ, Ritchie EG, Watson DM, Nimmo DG (2019) Topographic ruggedness and rainfall mediate geographic range contraction of a threatened marsupial predator. Diversity and Distributions PDF DOI

Life in linear habitats: the movement ecology of an endangered mammal in a peri‐urban landscape

Authors: Sarah J Maclagan, Terry Coates, Bronwyn A Hradsky, Ryan Butryn, and Euan G Ritchie

Published in: Animal Conservation


Animal movement can be significantly altered in human‐dominated landscapes such as urban and peri‐urban areas, where habitat is often fragmented and/or linear. Knowledge regarding how wildlife respond to anthropogenic change is vital for informing conservation efforts in such landscapes, including the design of nature reserves and wildlife corridors.

To better understand how threatened species persist and behave within human‐dominated landscapes, we examined the home range and space use of the nationally endangered southern brown bandicoot Isoodon obesulus obesulus in peri‐urban Melbourne, Australia’s second‐largest city. Specifically, we examined whether:

  • bandicoots were confined to linear strips of remnant vegetation or also made use of the broader highly modified landscape matrix;
  • the configuration of the linear vegetated strips affected home range shape; and
  • home range area differed between bandicoots living in linear strips and those in larger remnant habitat patches.

We found that:

  • 71% of adult males and 33% of adult females used the matrix, but non‐dispersing juveniles were entirely confined to the linear strips; males also travelled greater distances into the matrix (away from the vegetated strips) than females;
  • bandicoots had longer home ranges in narrower strips and males had longer home ranges than females; and
  • home range area for both sexes was smaller in linear strips than has been recorded in other studies in larger remnant habitats.

Our study highlights the importance of retaining narrow, fragmented and modified vegetation to accommodate threatened biodiversity within human‐dominated landscapes, but suggests the surrounding matrix may also offer important resources for adaptable species, such as bandicoots.

Supporting off‐reserve conservation of biodiversity in novel ecosystems is increasingly pertinent in our rapidly urbanizing world.

Maclagan SJ, Coates T, Hradsky BA, Butryn R, Ritchie EG (2019) Life in linear habitats: the movement ecology of an endangered mammal in a peri‐urban landscape. Animal Conservation PDF DOI

Restricted‐area culls and red fox abundance: Are effects a matter of time and place?

Authors: Jim‐Lino Kämmerle, Euan G Ritchie, and Ilse Storch

Published in: Conservation Science and Practice


Predators are often culled to benefit prey, but in many cases this conservation goal is not achieved or results remain unknown.

The red fox (Vulpes vulpes) is a predator of global significance, and an invasive species in some regions. Red fox culls intended to benefit prey are often restricted to small areas, and effectiveness is rarely sufficiently evaluated.

Given the economic, ecological, social, and welfare issues associated with lethal predator control, there is a strong need to assess the effects of spatiotemporal variation in culling intensity on red fox abundance.

We surveyed red fox populations in fragmented forests of south‐western Germany and related indices of local fox abundance to culling data, predicted landscape‐scale fox abundance, and other covariates. We tested whether restricted‐area culling was associated with local reductions in fox abundance, and examined how this relationship changed over time.

Local fox abundance was temporarily reduced in spring, following winter culls. However, the effect was minor and fox populations had compensated for the reductions at the latest by autumn. Restricted‐area culling therefore likely failed to sustain effects on fox abundance throughout the period most relevant for conservation (i.e., the reproductive period of the target prey species).

To be effective as a conservation tool, culling will therefore require explicit spatiotemporal coordination matching the biology of predators and target prey.

Kämmerle J, Ritchie EG, Storch I (2019) Restricted‐area culls and red fox abundance: Are effects a matter of time and place? Conservation Science and Practice PDF DOI

Science communication in a post‐truth world: promises and pitfalls

Authors: R Keller Kopf, Dale G Nimmo, Euan G Ritchie, and Jen K Martin

Published in: Frontiers in Ecology and the Environment

The mass decline of biodiversity in this post-truth era means that reliable and influential conservation science communication is more important than ever.

In this era, truths and lies are increasingly difficult to distinguish, posing a major challenge to science communication. As a result, conservation scientists and managers are grappling with new ways of countering misinformation and sharing factual information.

Facebook, Twitter, YouTube, Instagram, blogs, online news outlets, webcomics, and satirical articles all provide communication opportunities, but we still have a poor understanding of which of these are most effective, and when and where to best communicate science…

Kopf RK, Nimmo DG, Ritchie EG, Martin JK (2019) Science communication in a post-truth world: promises and pitfalls. Frontiers in Ecology and the Environment PDF DOI

The Conversation: Academia can help humans and large carnivores coexist

In Romania, wolves live in the same landscapes as shepherds. Image credit: Vlada Cech via Shutterstock.

By Euan Ritchie (Deakin University), Abi Vanak (University of KwaZulu-Natal), Benjamin Scheele (Australian National University), Laurentiu Rozylowicz, and Tibor Hartel

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bears, wolves, lions and other top predators have a long history of conflict with people – they can threaten our safety and kill livestock.

In our recent study, published in Conservation Biology, we outline how conventional conservation approaches are unlikely to lead to effective coexistence between humans and large carnivores in human-dominated landscapes.

This wicked problem encompasses public safety, agriculture, conservation, animal welfare, and more. Each facet is commonly managed by a different institution working in isolation – often failing to reflect the reality of our highly connected world.

Academia can help foster better institutional arrangements, especially in places like Romania, India and Brazil, where there are substantial populations of people and large carnivores in shared spaces.

In Romania, for instance, bears and wolves live in the same places used by shepherds and their livestock. Guardian dogs typically help protect livestock from being attacked.

Similarly, Australia’s own dingo occurs across agricultural and pastoral regions, with sentiments ranging from protected native species to disliked pest.

Why institutions fail carnivore-human relationships

From bears in Romania to dingoes in Australia, large carnivores are found in an array of places. This means they regularly affect the interests of a range of institutions, from agriculture to forestry.

But the current arrangements are poorly suited to facilitate a peaceful coexistence between humans and large carnivores.

Typically, institutions focus on a small subset of concerns. Forestry and agricultural sectors, for instance, may not feel responsible for large carnivore conservation because they are primarily interested in timber and agricultural production.

On the other hand, institutions for transport, energy and border security might be indifferent towards large carnivores. But they can negatively affect these animals if they put up barriers restricting predator movement and inappropriately handle roadkill.

These compartmentalised, and often conflicting, institutions are poorly suited to helping wildlife, especially when large carnivores, such as leopards, wolves and bears, live in human-dominated regions.

A role for academia

Academia has solutions to offer.

Most environment-related professionals, like foresters, wildlife managers and conservation biologists, are trained in a range of academic institutions. Unfortunately, they are often taught narrowly within their sector or discipline.

However, all these future professionals passing through the same institutions provides a great opportunity for a broad change in how we approach difficult conservation challenges and conflict with wildlife.

There are at least three ways in which academia could help address the challenges of human and large carnivore coexistence:

1. Break down the silos

Academic institutions need to create special centres to better support teaching and research across different disciplines.

Conservation – and, on a broader level, how humans should relate to the natural world – cannot be siloed away in wildlife management courses.

2. Broaden the view

We need to actively foster a broader perspective that does not see large carnivores as an “enemy”, while still safeguarding human life. This is a complex and multifaceted challenge.

By working across disciplines, universities have the chance to actively foster this broader perspective. This may seem like a nebulous point, but the collapse of species around the world has highlighted how ineffective our current approach to conservation is. We need to move beyond tinkering around the edges of our extinction crisis.

Conservation policy is already equipped to address individual targets such as regulating carnivore populations and legally protecting species. It is the larger aim of changing norms, challenging values and ensuring all these various institutions are pulling in the same direction that we need to tackle – a tactic called the “leverage points approach”.

3. Work outside the academy

Academia could support existing collaborations. When people with shared interests come together to pool knowledge and address a particular issue, we call it a community of practice. Academia can contribute to these communities by offering the skills and expertise of its graduates, but also broader social and industry connections (where required), knowledge sharing, collaborative research, education and technological innovation.

We need big carnivores and they need us

Large carnivores are critical for the health of ecosystems globally, and we need to provide them with enough space and tolerance to survive.

The ongoing controversy regarding the management of the dingo, Australia’s largest land-based predator (aside from humans), provides a perfect test case for this new approach to managing human-wildlife conflict.

If we can achieve more harmonious relations with the world’s top predators, many of the myriad other species that coexist with them are also likely to benefit from both better habitat management and conservation and the important ecological effects large carnivores can have, such as keeping herbivore and smaller predator numbers in check. This can be a positive step towards addressing Earth’s mass extinction crisis.

The authors would like to thank John Linnell, Senior Research Scientist at the Norwegian Institute for Nature Research, for his contribution to this article.
The Conversation

Threat webs: reframing the co-occurrence and interactions of threats to biodiversity

Authors: William L Geary, Dale G Nimmo, Tim S Doherty, Euan G Ritchie, and Ayesha IT Tulloch

Published in: Journal of Applied Ecology


Interactions between threatening processes and their effects on biodiversity are a major focus of ecological research and management. Threat interactions arise when threats or their effects co‐occur spatially and temporally.

Whether the associations between threats are coincidental or causally linked is poorly understood, but has fundamental impacts on how, when and where threats should be managed. We propose that examining threat co‐occurrence, supplemented by experiments and triangulation of evidence, can help identify when and where threats interact causally, informing pressing biodiversity management goals.

Using case studies, we demonstrate how co‐occurring and interacting threats can be visualised as networks (threat webs) and how this could guide conservation interventions at local, regional and global scales.

Synthesis and applications. Recognising that threats co‐occur and interact as networks, and are potentially driven by multiple agents (e.g. other threats, shared environmental drivers), helps us understand their dynamics and impacts on ecosystems. This greater understanding can help facilitate more targeted, efficient and effective environmental management.

Geary WL, Nimmo DG, Doherty TS, Ritchie EG, Tulloch AIT (2019) Threat webs: reframing the co‐occurrence and interactions of threats to biodiversity. Journal of Applied Ecology PDF DOI