Output list
Journal article
Published 2024
Australian Mammalogy, 46, 2, AM23023
Camera trap model and setup choice can significantly affect data collection. This study investigated standard-angle Reconyx and wide-angle Swift camera traps in different setups and how the choice of equipment influenced detection and individual identification of the chuditch (Dasyurus geoffroii). Camera models were placed side-by-side in four setups: (i) single and (ii) paired camera traps 30 cm above ground; and single cameras (iii) 1 m and (iv) 2 m above ground, with a lure (tuna oil) in the centre of all setups. Swifts had a higher Detection probability than Reconyx, although the number of detections with identified individuals did not significantly differ between camera models. The 30 cm paired camera setups had the highest Detection and Identification probabilities for both camera models, with both probabilities decreasing as cameras were positioned higher. Camera model and setup choice are important in obtaining detection and identification data, and should be considered when planning studies and interpreting results.
Journal article
Published 2023
Arthropod structure & development, 74, 101254
Conflicts of interest over reproduction between males and females are widespread in sexually reproducing species. This is exemplified in water striders (Gerridae), where females vigorously resist costly mating attempts, and males and females often exhibit elaborate grasping and anti-grasping morphological traits. Like water striders, their sister-group, the ripple bugs (Veliidae), share similar life histories and are expected to face similar conflicts over mating. Veliids in the genus Nesidovelia exhibit elaborate sexual dimorphism, which is predicted to function in intersexual antagonistic struggles. This includes concealed genitalia in females, and elaborate pregenital abdominal modifications in males. By documenting mating behaviour in Nesidovelia peramoena and freezing pairs in copula, we show that males and females struggle prior to mating, and male abdominal modifications function to gain access to the female's concealed genitalia. This is consistent with, though not limited to, sexual conflict.
Journal article
Published 2022
Pacific Conservation Biology;, 28, 1, 25 - 35
When using camera traps for wildlife studies, determining suitable camera models and deployment methods is essential for achieving study objectives. We aimed to determine if camera trap performance can be increased by (1) using cameras with wider detection angles, and (2) by periodically repositioning cameras within sites. We compared three camera trap groups: stationary Reconyx PC900/HC600 (40° detection angle), and paired, periodically-repositioned Reconyx PC900/HC600 and Swift 3C wide-angle camera traps (110° detection angle). Cameras operated simultaneously at 17 sites over 9 weeks within the Upper Warren region, Western Australia. Swift cameras had significantly higher detection rates, leading to better performance, especially for species <1 kg and >10 kg bodyweight. Reconyx cameras missed 54% of known events, with most being animals that moved within the cameras’ detection zones. Stationary and periodically-repositioned Reconyx camera traps performed similarly, although there were notable differences for some species. The better performance of Swift 3C wide-angle camera traps makes them more useful for community-level and species-level studies. The increased sensitivity of the Swift’s passive infrared sensor along with the wider detection zone played an important role in its success. When choosing camera trap models, detection angle and sensor sensitivity should be considered to produce reliable study results. Periodically repositioning cameras within sites is a technique that warrants further investigation as it may reduce camera placement bias, animal avoidance of camera traps, and increase spatial/habitat information when a limited number of cameras are deployed.
Journal article
Published 2021
Wildlife Research, Online early
Aims: To compare efficacy and costing of driven transects, sign surveys and camera trapping for detecting numbats in the Upper Warren region, Western Australia. Methods: Seven repeat sign surveys and driven transects, as well as 4 months of camera trapping, were conducted concurrently at 50 sites along three transects. Numbat detection rates and costing of the three techniques were compared, and detection probabilities were compared between sign surveys and camera trapping. Key results: Numbat signs were detected during 88 surveys at 39 sites, exceeding camera trapping (26 detections at 13 sites) and driven transects (seven detections near five sites). The estimated probability for detecting a numbat or a sign thereof (at a site where numbats were present) ranged from 0.21 to 0.35 for a sign survey, and 0.02 to 0.06 for 7 days of camera trapping. Total survey costs were lowest for driven transects, followed by camera trapping and sign surveys. When expressed as cost per numbat detection, sign surveys were cheapest. Conclusions: Comparative studies of survey methods are essential for optimal, cost-effective wildlife monitoring. Sign surveys were more successful and cost effective than camera trapping or driven transects for detecting numbats in the Upper Warren region. Together with occupancy modelling, sign surveys are appropriate to investigate changes in occupancy rates over time, which could serve as a metric for long-term numbat monitoring. Implications: There is no ‘best’ method for wildlife surveys. Case-specific comparison of animal detection methods is recommended to ensure optimal methods. For the numbat population in the Upper Warren region, further studies are needed to improve numbat detection rates from camera trapping, and to test sign surveys in autumn (March to May), when surviving juvenile numbats have established their own territory and assumptions regarding population closure are less likely to be violated.
Journal article
Published 2020
Australian Mammalogy, 43, 2, 226 - 234
Camera traps are widely used to collect data for wildlife management, but species-specific testing is crucial. We conducted three trials to optimise camera traps for detecting numbats (Myrmecobius fasciatus), a 500–700-g mammal. We compared detection rates from (1) Reconyx PC900 camera traps installed at heights ranging from 10–45 cm, and (2) Reconyx PC900, Swift 3C standard and wide-angle camera traps with differing detection zone widths. Finally, we compared elevated, downward-angled time-lapse cameras installed at heights ranging from 1–2 m to obtain dorsal images for individual numbat identification. Camera traps set at 25 cm had the highest detection rates but missed 40% of known events. During model comparison, Swift 3C wide-angle camera traps recorded 89%, Swift 3C standard 51%, and Reconyx PC900 37% of known events. The number of suitable images from elevated, downward-angled cameras, depicting dorsal fur patterns, increased with increasing camera height. The use of well regarded camera trap brands and generic recommendations for set-up techniques cannot replace rigorous, species-specific testing. For numbat detection, we recommend the Swift 3C wide-angle model installed at 25-cm height. For individual numbat identification, elevated, downward-angled time-lapse cameras were useful; however, more research is needed to optimise this technique.
Journal article
Published 2018
Scientometrics, 115, 2, 731 - 748
Authors or journals often claim internationality or multidisciplinarity based on assertion or qualitative evidence, while scientometric studies employ sophisticated analyses or software beyond the resources of occasional users to assess these concepts. This paper demonstrates how statistics used to describe ecological communities can be applied to bibliometric data to quantify internationality or multidisciplinarity for individuals and journals, enabling tests of statistical significance using graphical user interface freeware accessible to even occasional users. Margalef Richness, diversity and evenness or equitability can be calculated to indicate whether papers or citations come predominantly from a small group of countries or disciplines, or are more widely distributed. Tests of statistical significance for differences in Margalef richness, diversity or evenness between authors or journals enable testing of diverse hypotheses including, for example: differences in internationality or multidisciplinarity between authors or between journals; or changes over time in these variables for authors or journals (perhaps in response to career changes or changes in editorial policy). Quantifying internationality and multidisciplinarity in an accessible way for many potential users, with the possibility of statistical hypothesis testing, is a significant advance over assertion and qualitative description on the one hand or conceptually and practically complex analysis on the other.
Journal article
Teaching evolution to creationist students: the ultimate challenge
Published 2017
Australian Zoologist, 38, 3, 318 - 328
Despite overwhelming evidence for the common ancestry of life and evolution by natural selection, ideas invoking direct creation persist, disrupting teaching evolution as a central biological concept. While originating within fundamentalist Protestantism in the USA, creationist views are now prominent elsewhere and in other religions. Responses by educators include ignoring evolution; excluding evolutionary topics especially provocative to creationist students; advocating evolution while ignoring, disparaging or ridiculing creationism; distinguishing between scientific and religious approaches before considering only the scientific; and acknowledging evolution and creationist positions as different world views that one may understand, but not necessarily accept. Here, we argue that any chance of success in teaching evolution to creationist students requires elements of the last two of these approaches. Applying them requires understanding students' worldviews and the methods and limitations of science, as well as employing learning activities that engage, not alienate. In this context, we describe the creationist positions that may be encountered when teaching evolution, the fundamentals appropriate to teaching scientific method, and the teaching strategies of affirmative neutrality and procedural neutrality that educators may use to counter creationist views when teaching evolution. We regard understanding of the common ancestry of life and natural selection and other evolutionary mechanisms as threshold concepts that, once grasped, can transform students' interpretations of biology and possibly their world views. Mentioning creationism in the context of science education may be a dangerous idea, but what is worse - to establish some common ground with creationist students in the hope of leading them to an understanding of evolution, or to leave them ignorant of any evolutionary concepts at all?
Journal article
Diet of the critically endangered woylie (Bettongia penicillata ogilbyi) in south-western Australia
Published 2017
Australian Journal of Zoology, 65, 5, 302 - 312
To assist the management of the critically endangered woylie (Bettongia penicillata ogilbyi), a quantitative study of its diet was conducted across five of the larger subpopulations in south-Western Australia. There was a close match between dietary composition established from foregut contents and faecal pellets. Woylies were predominantly mycophagous in all subpopulations, but consumed a broad diet including invertebrates, seeds and other plant material. Individuals in a high-density, fenced subpopulation ate significantly less fungi than free-ranging animals from lower-density subpopulations. Dietary composition did not vary significantly amongst subpopulations in the Upper Warren region, where a range of population densities was observed. Altogether, 79 fungal spore classes were identified, including at least 15 genera from 14 families. Sampling across one year showed that fungi made up a larger fraction of the diet in autumn or winter, and greater diversities of fungi were consumed at these times than at other times of year. This information is essential to provide valuable ecological context for effective population management of woylies, as well as identification and conservation of important habitats.
Journal article
Published 2017
Journal of Wildlife Rehabilitation, 37, 2, 11 - 31
International differences in practices and attitudes regarding pet cats' interactions with wildlife were assessed by surveying citizens from at least two cities in Australia, New Zealand, the UK, the USA, China and Japan. Predictions tested were: (i) cat owners would agree less than non-cat owners that cats might threaten wildlife, (ii) cat owners value wildlife less than non-cat owners, (iii) cat owners are less accepting of cat legislation/restrictions than non-owners, and (iv) respondents from regions with high endemic biodiversity would be most concerned about pet cats threatening wildlife. Everywhere non-owners were more likely than owners to agree that pet cats killing wildlife were a problem in cities, towns and rural areas. Over 85% of respondents from all countries except China valued wildlife in cities, towns and rural areas. Non-owners advocated cat legislation more strongly than owners except in Japan. Many Australian (62%), New Zealand (51%) and Chinese owners (42%) agreed that pet cats killing wildlife in cities, towns and rural areas was a problem, while Hawaiian owners were similar to the mainland USA (20%). Thus high endemic biodiversity might contribute to attitudes in some, but not all, countries. Husbandry practices varied internationally, with predation highest where fewer cats were confned. Although the risk of wildlife population declines caused by pet cats justifes precautionary action, campaigns based on wildlife protection are unlikely to succeed outside Australia or New Zealand. Restrictions on roaming protect wildlife and beneft cat welfare, so welfare is a better rationale.
Journal article
Factors determining the home ranges of pet cats: A meta-analysis
Published 2016
Biological Conservation, 203, 313 - 320
Roaming pet cats Felis catus are a significant conservation issue because they may hunt, harass and compete with wildlife; spread disease, interbreed with cats in feral populations, and hybridise with wild native felids. Studies of the roaming behaviour of pet cats are often hampered by modest sample sizes and variability between cats, limiting statistical significance of the findings and their usefulness in recommending measures to discourage roaming. We resolved these difficulties through meta-analyses of 25 studies from 10 countries involving 469 pet cats to assess the influence of sex, whether a cat was desexed and housing density on roaming. A complementary linear mixed models approach used data on 311 individual animals from 22 studies and was also able to assess the influence of age and husbandry practices on roaming. This restricted sample gave greater statistical power than the meta-analyses. Meta-analyses found that: male pet cats had larger home ranges than females, desexing did not influence home range, and cats had larger home ranges when housing densities were low. The linear mixed models supported those results. They also indicated that animals ≥ 8 years old had smaller home ranges than younger cats. Cats fed regularly, provided with veterinary care and socialised with humans had similar home ranges to cats living in association with households but not provided for in some of these ways. Short of confinement, there is no simple measure owners can adopt to reduce roaming by their cats and prevent the associated environmental problems.