Can remote infrared cameras be used to differentiate small, sympatric mammal species? A case study of the black-tailed dusky antechinus, Antechinus arktos and co-occurring small mammals in southeast Queensland, Australia

Abstract

The black-tailed dusky antechinus (Antechinus arktos) is an endangered, small carnivorous marsupial endemic to Australia, which occurs at low population density along with abundant sympatric populations of other small mammals: Antechinus stuartii, Rattus fuscipes and Melomys cervinipes. Using A. arktos as a model species, we aimed to evaluate the effectiveness of infrared digital camera traps for detecting and differentiating small mammals and to comment on the broad applicability of this methodology. We also sought to understand how the detection probabilities of our target species varied over time and characterize their activity patterns. We installed 11 infrared cameras at one of only three known sites where A. arktos occurs for five consecutive deployments. Cameras were fixed to wooden stakes and oriented vertically, 35 cm above ground, directly facing bait containers. Using this method, we successfully recorded and identified individuals from all four species of small mammal known previously in the area from live trapping, including A. arktos. This validates the effectiveness of the infrared camera type and orientation for small mammal studies. Periods of activity for all species were highly coincident, showing a strong peak in activity during the same two-hour period immediately following sunset. A. arktos, A. stuartii and M. cervinipes also displayed a strong negative linear relationship between detection probability and days since deployment. This is an important finding for camera trapping generally, indicating that routine camera deployment lengths (of one-to-two weeks) between baiting events may be too long when targeting some small mammals.

Vegetation structure and ground cover attributes describe the occurrence of a newly discovered carnivorous marsupial on the Tweed Shield Volcano caldera, the endangered black‐tailed dusky antechinus (Antechinus arktos)

“…obs. ; Gray, Dennis, et al, ; McCormack, ). Notable differences in habitat structure between the studied sites are largely ground‐based, presumably providing better refugia for small, terrestrial mammals like A. arktos from these feral predators.…”

“…Forested environments, such as the Gondwanan rainforest relics of the Tweed Shield Volcano caldera, harbor much of the endemic and endangered faunal species occurring in Australian states (Figgis, ; Scarlett et al, ). Since description of A. arktos in 2014, the species has been listed as endangered under both state and federal legislation, due to its highly fragmented, high‐altitude habitat, limited potential for distribution on the caldera, extremely low apparent abundance, and a range of threats exacerbating these problems (Baker et al, ; Gray, Baker, et al, ; Gray, Burwell, & Baker, ; Gray, Dennis, & Baker, ). However, these factors remain poorly understood and need urgent research to ensure effective conservation management (Baker et al, ; Gray, Baker, et al, ; Gray et al, ; Gray, Dennis, et al, ).…”

“…Since description of A. arktos in 2014, the species has been listed as endangered under both state and federal legislation, due to its highly fragmented, high‐altitude habitat, limited potential for distribution on the caldera, extremely low apparent abundance, and a range of threats exacerbating these problems (Baker et al, ; Gray, Baker, et al, ; Gray, Burwell, & Baker, ; Gray, Dennis, & Baker, ). However, these factors remain poorly understood and need urgent research to ensure effective conservation management (Baker et al, ; Gray, Baker, et al, ; Gray et al, ; Gray, Dennis, et al, ). Foundational studies have been conducted on the species' taxonomy by Baker et al () and reproductive biology, population dynamics, and dietary preference by Gray et al (), Gray, Baker, et al (), and Gray, Dennis, et al ().…”

“…However, these factors remain poorly understood and need urgent research to ensure effective conservation management (Baker et al, ; Gray, Baker, et al, ; Gray et al, ; Gray, Dennis, et al, ). Foundational studies have been conducted on the species' taxonomy by Baker et al () and reproductive biology, population dynamics, and dietary preference by Gray et al (), Gray, Baker, et al (), and Gray, Dennis, et al (). Information on the species' habitat use and preference represents a crucial knowledge gap.…”

Determining the efficacy of camera traps, live capture traps, and detection dogs for locating cryptic small mammal species

“…Camera traps, unlike live trapping methods, can operate 24 hr a day and may run for extended periods in a variety of landscapes and weather conditions (González‐Esteban et al, ; Peterson & Thomas, ; Vine et al, ). Camera trapping ultimately removes the need to physically handle an individual and offers a means of detecting rare, elusive, or trap‐shy individuals that may be missed by traditional, intensive, shorter‐duration live trapping methods (Gray, Dennis, & Baker, ; Rendall, Sutherland, Cooke, & White, ).…”