Austral Ecology最新文献

Camera trapping is an increasingly popular method for surveying wildlife, especially for conservation management. Two important considerations in the design of camera surveys are (a) the number of detection units (cameras or camera-groups) per site and (b) deployment time. The trade-off between these two factors will likely affect data quality and quantity, but there is little information about their relative influence on species detectability. In this study we investigated the trade-off between deploying more detection units or extending the length of the sampling period on two frequently assessed variables in camera trapping studies—species richness and detection probability. Camera traps were established along ten transects in the Central Highlands of Victoria, Australia, to target small, medium and large native mammals. We used a bootstrapping procedure to iteratively sample each possible combination of detection units (1–6 camera pairs) and deployment days (1–34). The procedure randomly resampled the data with replacement, repeating the process 1000 times for every combination and calculated (a) the number of species detected and (b) species-specific daily detection probability at each iteration. Multiple detection units in combination with longer deployment times were necessary to detect a high proportion of species present. Increasing the number of detection units or deployment time (or both) resulted in high overall detection probability for the more detectible species in our study region, but multiple detection units were always needed to achieve high detection probability in a reasonable timeframe (< 50 days) for less detectible species. We found that adding extra detection units provided benefits over and above longer deployment times. These findings will guide decision-making about the number of cameras and length of deployment required for efficient and effective camera trapping surveys.

Changes in vegetation density and phenology are widely attributed to rising temperatures and altered precipitation. In South Africa, however, recent climate change has been characterised primarily by increasing temperature extremes rather than shifts in mean conditions. We assessed vegetation greenness and phenology using enhanced vegetation index (EVI) data from 154 protected areas (> 100 km²; 2001–2024) and trends in climate extremes and seasonality at 42 weather stations (1980–2024). EVI showed few significant long-term trends and no systematic shifts in phenology (start, peak or end of growing season) at individual reserves, despite strong seasonal cycles. Mixed-effects models across all reserves, however, detected small but significant decadal increases in EVI and a possible delay in the end of the growing season—a subtle signal not apparent in individual reserves. Maximum temperatures increased by 0.52°C decade⁻¹ and annual temperature range increased markedly, while mean annual precipitation showed no coherent national trend despite longer wet spells and higher extremes. These limited and spatially inconsistent changes suggest that increasing temperature extremes have not yet driven widespread or ecologically substantial vegetation responses in the protected areas examined. This is possibly because much of this vegetation is water-limited, precipitation has changed little nationally, and photoperiod may constrain growing-season timing shifts. A climate–EVI linkage analysis confirmed EVI responds to inter-annual climate variability, with precipitation anomalies the dominant predictor and temperature anomalies also significant, though climate explained only a modest fraction (R² = 12.4%) of reserve-level EVI variation. Where sustained rainfall declines did occur, such as at Springbok (−46 mm decade⁻¹), corresponding EVI declines were observed in adjacent protected areas, consistent with water availability as the dominant constraint in these systems. Overall, we found little evidence for systematic shifts in climate seasonality in contrast to reports for extratropical regions. Instead, recent climate change across most of South Africa has intensified extremes without yet producing widespread ecological responses in vegetation greenness or phenology.

The Brazilian Cerrado harbours a highly diverse and well-represented anuran fauna, yet the effects of anthropogenic factors, such as roads, habitat loss and fragmentation, on these assemblages remain poorly understood. In the present study, we address this knowledge gap by testing the relationship between landscape metrics and anuran assembly (richness, composition and ecological traits) in the Brazilian Cerrado. Using passive acoustic monitoring, we recorded 32 species in 31 breeding habitats of anurans (water bodies) located in the southwestern region of Goiás State, Brazil. Higher species richness was present in the breeding habitats within the more connected landscapes (landscapes with lower edge density and fewer native vegetation patches) and located farther from roads. Conversely, species richness decreased in landscapes with more native habitats. While habitat isolation caused by roads or agricultural lands negatively affects anuran diversity by hindering gene flow and recolonization between the terrestrial and breeding habitats, a phenomenon known as habitat split, particularly in species with low dispersal capacity and high sensitivity to desiccation. Small artificial reservoirs created for cattle management are frequently used by anurans as breeding sites. These reservoirs may play a crucial role in maintaining species richness, particularly for open-habitat species, despite the reduction of native vegetation in the landscape. We recommend that the effect of artificial reservoirs despite the surrounding native vegetation be addressed in future studies. Thus, our findings provide new insights and contribute to a better understanding of how the anuran fauna of the Cerrado respond to anthropogenic landscapes.

Small mammal diversity is crucial for maintaining the functioning of urban ecosystems. However, small mammal diversity estimates obtained by live-trapping are strongly influenced by animal behaviour. We live-trapped small mammals in five urban reserves, each paired with a natural forest counterpart within Ku-ring-gai Chase National Park, New South Wales, Australia. We used Elliot traps paired with camera traps to observe the activity, boldness, and trappability of small mammals. We found that the activity of small mammals did not differ between the urban reserve and forest sites. However, we found that the most active species in urban reserves was the invasive black rat (Rattus rattus; Muridae), whereas the native bushrat (R. fuscipes; Muridae) was the most active species in forest sites, which greatly influenced our results. We found that the small mammals in the urban reserves were less bold and had lower trappability than their forest counterparts. This could be explained by the bait type, and/or traits of the small mammal species (mostly R. rattus) that were dominant in the urban reserves. Our study also highlights the importance of using camera-trapping in conjunction with live-trapping when assessing small mammal behaviour towards trapping devices to increase the accuracy of diversity estimates obtained by live-trapping.

Soil fungi regulate terrestrial ecosystem function and productivity. Native digging mammals influence soil physiochemistry, thus likely affect soil fungal communities; yet despite their re-establishment in many parts of arid Australia, the influence of digging mammals on soil fungi in reintroduction areas remains largely unknown. We used high-throughput DNA sequencing to characterise the soil fungal community at an arid mammal restoration site (Wild Deserts) and an adjacent area where digging mammals are extirpated, as well as to assess the fungal content of scat from a reintroduced digging mammal, the greater bilby (Macrotis lagotis). We assessed the richness, composition, spatial evenness and abundance of fungal functional guilds in soil samples taken inside and outside the reserve. Additionally, we assessed the composition of fungi and fungal functional guilds in bilby scat samples collected at several timepoints (pre- and post-reintroduction). Approximately 3 years after initial reintroductions, the soil fungal community did not differ in any of the assessed measures between digging mammal-present and –absent areas. In bilby scats, there were significant differences in fungal guilds detected between the sampling periods. Litter-saprotrophic fungus Chlorophyllum was more abundant in bilby scats collected three-years post release at Wild Deserts, compared to those collected pre-release and relatively high abundance of Chlorophyllum in several scats may point to opportunistic consumption of the fungus by bilbies. While we did not observe differences in the soil fungal community inside and outside the restoration area within the study period, the strong overlap between fungal taxa detected in soil samples and post-release scats is consistent with bilbies interacting with fungi in the environment at Wild Deserts. Our work highlights a need to improve knowledge of Australian arid-zone fungi, and for long-term monitoring regimes to establish benchmarks for fungal communities and elucidate the mechanisms and timescales by which digging mammals affect soil fungal restoration.

Freshwater turtles worldwide face escalating threats resulting from habitat alteration, and the absence of detailed assessments for many taxa underscores the need for greater attention. In northern Australia, feral ungulates are a major driver of wetland degradation, with emerging evidence that buffalo activity threatens freshwater turtle populations. Modelling has identified the normally protective states of aestivation and embryo development in Chelodina rugosa as potential points of vulnerability amid escalating buffalo numbers. This study examined how buffalo alter subsurface conditions relevant to aestivation and nesting by quantifying rooted ground-layer vegetation, thermal regimes, gravimetric soil moisture and trampling in areas exposed to and excluded from buffalo over three habitat types in the Arafura Swamp Indigenous Protected Area. Buffalo presence markedly reduced subsurface habitat quality, increasing temperature and thermal variability, reducing soil moisture and rooted ground-cover vegetation and causing direct trampling of nests. These changes are likely to increase energetic costs during aestivation and reduce embryo survivorship. Such impacts on subsurface microhabitats are expected to intensify under predicted climatic changes and rainfall variability, further constraining the species' capacity to maintain successful aestivation over extended periods and maintain reproductive rates. Our findings highlight the need for targeted buffalo management to protect critical subsurface refugia for C. rugosa in northern Australian wetlands. Additionally, many other fauna rely on subsurface refugia during the dry season, including amphibians, other reptiles and invertebrates such as crustaceans and insects; these buffalo-induced impacts are likely to have much broader ecosystem-level consequences.

In many regions there are disputes about future land use that make knowledge of spatial variation in conservation value an important input to negotiation. Current approaches to measuring spatial conservation values for the purposes of recognition and protection remain largely trapped in colonising cartographic methodologies that marginalise Indigenous knowledges and valuing of Indigenous lands (country). One such current approach is simple additive weighted methods which are unable to recognise relational values. We reflect on the use of these methods in the case study of Takayna country, in Trouwerner and Lutruwita/Tasmania, Australia. The hegemonic IUCN framework for protected areas is yet to be decolonised, allowing the settler state to value Takayna country though white possession of conservation without its Aboriginal values. In recognition of these fundamental deficiencies, we attempt to mitigate the limitations of the simple additive weighted method by including additional values of importance. We weighted the importance of individual heritage attributes by assessing the global concentration of representation of individual values in the region and relating the degree of concentration to recognised criteria for international, national, State and regional significance. Our analysis indicated that much of the region was of global significance on several natural criteria, with the coast and the inland rainforest areas standing out for their high conservation value. Despite our conclusion that Takayna country has internationally significant values that may meet World Heritage criteria iii, v, vi, vii and x, we demonstrate that colonial cartography is unjust and unable to measure, interpret and resolve disputed conservation values of sovereign bodies of country. Alternative approaches that address the past neglect of cultural values and enable strong Indigenous governance, formal recognition of First Peoples, and land return, are crucial for integrating First Peoples' knowledges, caring for country and relationships with country into conservation planning and management, ultimately improving conservation outcomes.

Habitat structure mediates thermoregulation, foraging opportunities, and access to refugia, shaping how animals use space and encounter risk. Dune–swale mosaics provide sharp structural contrasts over short distances, offering a natural test of structure–assemblage links and spacing relative to shelter. We compared lizard assemblages and the positions of active lizards relative to vegetative cover across interdunal swales and adjacent sand dunes in central South Australia. At replicated sites in Arid Recovery Reserve and Andamooka Pastoral Station, we quantified vegetation and ground-layer structure, sampled assemblages with pitfall traps and active searches, and measured each active lizard's distance to the nearest vegetative refuge. We tested whether the expected structural contrast between dunes and swales was evident at our study sites, whether lizard community composition and assemblage metrics differed between landforms, and whether active lizards in structurally simpler habitat occurred closer to vegetative cover than those in more complex habitat. Dunes were more structurally complex than swales, lizard communities differed significantly between landforms, and abundance was higher on dunes, whereas richness and diversity were broadly comparable. However, active lizards in both landforms occurred at similar distances to vegetative cover. These findings identify habitat structure as a key driver of assemblage differences, while showing that we did not detect a significant habitat-level difference in active lizards' distance to vegetative cover under the present sampling design. We interpret implications for predation risk broadly in a multi-predator context and recommend coupling behavioural metrics with predator-activity indices and repeating sampling across wet and dry years.