Context. Mesopredators experience top down pressure from apex predators, which may lead to behavioural changes such as spatial avoidance to reduce both interference and exploitative competition. However, apex predators may also facilitate mesopredators through the provision of carrion, so mesopredators should respond flexibly to the presence of apex predators.

Aims. We aimed to investigate the drivers of black-backed jackal (Canis mesomelas) space use and detection in areas with and without lions (Panthera leo). We predicted that jackal detection and space use will be greater if apex predators facilitate rather than suppress them. Additionally, we predicted that in the absence of lions, the relative abundance of small ungulate species may become important drivers of space use and detection, because jackals can switch from scavenging to hunting. Comparatively, in the presence of lions, larger ungulate species will become important drivers of space use and detection as these species become accessible to jackals through scavenging.

Methods. We used camera-trapping surveys, a single-species, single-season occupancy modelling approach, and the assessment of activity patterns to explore how apex predators influence the presence and probability of use of different sites in the Eastern Cape province of South Africa.

Key results. Apex predators both positively and negatively affected the detection of jackals, indicating that these mesopredators show behavioural flexibility at the individual site level. There was high overlap between jackal activity patterns in the presence and absence of lions; however, at one site with lions, jackal activity did not peak at night as observed at other sites.

Conclusions. Our results indicate that jackals demonstrate behavioural flexibility in the presence and absence of apex predators. Importantly, our results show that apex predators can both facilitate and suppress mesopredators, and that their behavioural responses are dependent on site-specific factors.

Implications. Our findings highlight that sympatric predator behaviours should be based on site-specific behaviours instead of the general patterns observed in more temperate systems.

Context. Nest predation is a leading cause of nest failure for most ground-nesting birds. Methods that allow for accurate classification of fate and identification of predators are important for understanding productivity and conservation strategies. Past studies have used a visual inspection of nest remains to determine nest fate and predict predator identity. Most formal assessments of these methods have addressed small-bodied birds nesting in trees or shrubs, and have revealed that use of evidence at nests can be relatively accurate for determining nest fate but may lead to incorrect conclusions regarding predator identity. However, few have tested the latter hypothesis for larger ground-nesting birds with precocial young.

Aim. We aimed to evaluate a classification system developed for determining nest fate and identifying predators of waterfowl nests, at both the scale of individual nests and across the study area.

Methods. From 2016 to 2020, we located 989 blue-winged teal (Spatula discors), mallard (Anas platyrhynchos) and gadwall (Mareca strepera) nests in central North Dakota. We placed cameras at a subset of 249 nests and recorded evidence of nest remains at depredated nests.

Key results. The most common predators were American badgers (Taxidea taxus), followed by striped skunks (Mephitis mephitis), raccoons (Procyon lotor) and red foxes (Vulpes vulpes). Using evidence of nest remains, we determined nest fates with high accuracy (98.0%). However, evidence of nest remains was only sufficient for identifying predators at 50% of nests, and the classification system was correct only 69.7% of the time. The predicted proportion of predators across the study area differed between the classification system and our video evidence as well.

Conclusions. The accuracy of predator identifications based upon the classification system that we evaluated was not supported at any scale.

Implications. Our results suggest that evidence of nest remains can be used to determine nest fate for large-bodied precocial, ground-nesting birds, but accurate identification of nest predators will require alternative methods such as nest cameras.

Context. Camera trapping is an effective tool for cost-efficient monitoring of species over large temporal and spatial scales and it is becoming an increasingly popular method for investigating wildlife communities and trophic interactions. However, camera trapping targeting rare and elusive species can be hampered by low detection rates, which can decrease the accuracy and precision of results from common analytical approaches (e.g., occupancy modeling, capture-recapture). Consequently, researchers often employ attractants to increase detection without accounting for how attractants influence detection of species among trophic levels.

Aims. We aimed to evaluate the influences of a commonly used non-species-specific olfactory lure (i.e. sardines) and sampling design on detection of four species (i.e. bobcat [Lynx rufus], coyote [Canis latrans], raccoon [Procyon lotor], and eastern cottontail [Sylvilagus floridanus]) that represented a range of foraging guilds in an agricultural landscape.

Methods. We set 180 camera stations, each for ∼28 days, during the summer of 2019. We set cameras with one of three lure treatments: (1) olfactory lure, (2) no olfactory lure, or (3) olfactory lure only during the latter half of the survey. We evaluated the influence of the lure at three temporal scales of detection (i.e. daily probability of detection, independent sequences per daily detection, and triggers per independent sequence).

Key results. The lure tended to positively influence detection of coyotes and raccoons but negatively influenced detection of bobcats and eastern cottontails. The influence of the lure varied among temporal scales of detection.

Conclusions. Scent lures can differentially influence detection of species within or among tropic levels, and the influence of a scent lure may vary among temporal scales.

Implications. Our results demonstrate the importance of evaluating the influence of an attractant for each focal species when using camera data to conduct multi-species or community analyses, accounting for variation in sampling strategies across cameras, and identifying the appropriate species-specific temporal resolution for assessing variation in detection data. Furthermore, we highlight that care should be taken when using camera data as an index of relative abundance (e.g. as is commonly done with prey species) when there is variation in the use of lures across cameras.

Context. Invasive predators are major drivers of global biodiversity loss. Red foxes (Vulpes vulpes) and feral cats (Felis catus) have contributed to the decline and extinction of many native species in Australia. The deployment of poison baits to control fox populations is a widespread conservation tool, but the effects of baiting intensity, rainfall and prey abundance on baiting effectiveness remain poorly understood.

Aims. We aimed to understand what influences the association between fox baiting intensity, red fox activity and feral cat activity, to provide inferences about what might affect the effectiveness of fox baiting in reducing fox activity.

Methods. We used generalised linear models to assess how fox and cat activity changes in relation to fox baiting intensity, rainfall, native prey availability and distance to agricultural land over a 6-year period (2006–13) in the forest ecosystems of the Upper Warren region of south-western Australia.

Key results. We found that fox activity was negatively associated with rainfall in the previous 12 months and positively associated with prey abundance and fox baiting intensity. We also found an interaction between fox baiting and prey abundance, with fox activity increasing with prey activity in areas of low and moderate baiting intensity, but remaining constant in areas of high baiting intensity. Feral cat activity was positively associated with prey abundance and fox baiting intensity. We found no clear relationship between fox and cat activity.

Conclusions. The drivers of the association between fox baiting and fox activity are unclear because intense fox baiting was targeted at areas of known high fox abundance. However, our results indicate that intense fox baiting may be effective at decoupling the positive association between fox activity and prey abundance. Our results also suggest a positive association between fox baiting intensity and feral cat activity, thus supporting the case for integrated fox and cat management.

Implications. We caution interpretation of our results, but note that management of invasive predators could be improved by adjusting the intensity of management in response to changes in environmental conditions and local context (e.g. strategically conducting intense predator management where prey abundance is highest). Improved understanding of these associations requires a monitoring program with sufficient replication and statistical power to detect any treatment effects.

Context. The behaviours used by mammalian predators to track, kill, and consume prey are some of the most dynamic interspecific interactions in nature. However, they are often challenging to follow through the landscape and observe directly without disturbing the animals being watched.

Aims We describe the behaviours used by wild dingoes while hunting macropods in Namadgi National Park, Australian Capital Territory, Australia.

Methods. Footage was initially captured by wildlife cinematographers on behalf of documentary programs and was made available for viewing after production. Hunting events were filmed from an altitude of >50 m by using a ‘long lens’ fitted to either a drone or helicopter.

Results. We recorded a suite of hunting behaviours that would have been extremely challenging to observe from the ground via traditional methods. This includes some of the first video records published in the scientific literature of the behaviours used by dingoes to hunt and kill macropod prey, as well as some rare observations of mother and pup hunting dynamics. We did not observe any signs of disturbance as a result of filming for either predator or prey.

Conclusions. The varied repertoire of predatory behaviours displayed by dingoes is similar to that documented in wolves and asserts them as a behaviourally complex top predator in the Australian landscape. In addition, we highlight the use of drones as a valuable approach for directly observing wild behaviours. They offer a minimally invasive and relatively inexpensive and accessible alternative to helicopters. This project is also a case study exemplifying the value of collaborations between filmmakers and researchers that enable the sharing of archival documentary footage for the study of wild animal behaviour.

Implications. Future studies of wild animal behaviour should consider employing drones (at a safe distance and in accordance with published best practices and guidelines) as an additional tool to collect types of data that would be challenging using other methods.

Context. The common methods for detecting prey in faeces are traditional morphological examination of digested prey remains and faecal DNA (fDNA) metabarcoding. Although recent studies have shown that fDNA metabarcoding can identify prey that is excreted without morphologically identifiable remains, it is unclear whether fDNA metabarcoding provides a more comprehensive assessment of diet than morphological analyses.

Aims. We aimed to compare prey detection abilities of morphological and fDNA-metabarcoding assays by evaluating similarities and differences of estimated prey communities. We also aimed to provide the first comprehensive prey composition of an endangered ground-dwelling gecko, Goniurosaurus kuroiwae, which will contribute to the conservation management of this species.

Methods. We identified the prey consumed by G. kuroiwae by morphological examination and fDNA metabarcoding using the same series of faecal samples. For these two methods, we compared the overall community composition of prey items and the detection rate for each prey type. We also tested for environmental and ontogenetic variation of the composition of prey items consumed.

Key results. When comparing the two methods there were significant differences in the composition of prey communities that were identified from the same series of faecal samples. The fDNA metabarcoding analyses showed the higher rate of detection of earthworms, amphipods and coleopteran and lepidopteran larvae, which lack hard exoskeleton or have small body sizes. The morphological assay allowed identification of a few prey types, including spiders and earwigs, more frequently than fDNA metabarcoding. Combined use of both methods revealed that G. kuroiwae consumed large-sized invertebrates with a slight ontogenetic shift from small-sized invertebrates to large-sized ones.

Conclusions. Although fDNA metabarcoding showed the higher overall prey detection rate, it did not include all the prey items detected by morphological analysis. The complementary use of both methods can yield better understanding of the prey composition of invertebrate-consuming animals represented by reptiles and amphibians.

Implications. We have shown that the most comprehensive reconstruction of prey composition from faeces will be achieved by combining results from both fDNA metabarcoding and morphological analyses.