Austral Ecology最新文献

The Rio Negro Frog (Atelognathus nitoi) is an amphibian species endemic to Patagonia, shared between Argentina and Chile. Currently, it is classified as Vulnerable (IUCN) and is mainly threatened by anthropogenic pressures such as habitat alteration and climate change. Due to its life history and habitat requirements, primarily determined by temperature and precipitation, climate change may particularly influence the species' distribution. We evaluated how climate change may affect geographic range by producing a Species Distribution Model (SDM), generating a habitat suitability map and calculating its Extent of Occurrence (EOO). Projections were made for the period 2041–2060 under the Shared Socioeconomic Pathways SSP1-2.6 and SSP5-8.5, representing optimistic and pessimistic climate change scenarios, respectively. A set of five atmosphere–ocean general circulation models was used to reduce uncertainty. We evaluated the degree of connectivity of the lagoons with records of the species by applying Lin's functional linkage index, allowing comparisons in terms of their relative importance for the system's connectivity. Our results indicate an increase in suitability area over time, with a westward distribution shift in future scenarios. However, local extinctions are projected at the northern and southern margins of the species' range. Therefore, although the EOO is expected to expand, the species' life-cycle characteristics, limited dispersal capacity and low connectivity between the populations analysed should be taken into account when planning conservation actions.

The reintroduction of top-order predators is a proposed solution to address mesopredator release and overabundant herbivores, by regulating prey species and bringing ecosystems back into balance. However, few rigorous experiments document the post-release effects of reintroducing predators. We investigated potential ecosystem effects after the reintroduction of a native predator (western quoll, Dasyurus geoffroii) to a fenced conservation reserve in Australia, where reintroduced herbivores (burrowing bettong, Bettongia lesueur) and mesopredators (sand goannas, Varanus gouldii) were abundant in the absence of any large mammalian predators. We predicted that quoll predation would reduce the abundance of bettongs and sand goannas, leading to reduced browsing damage and higher ground vegetation cover, as well as increased abundance of small reptiles (goanna prey species) respectively. Quolls appeared to suppress bettongs within the reserve, resulting in reduced browsing damage on sensitive seedlings, but we were unable to document consistent cascading effects on vegetation. Quolls suppressed goannas inside the reserve and we documented an increase in trap success of small dragons (agamids) in dune habitats preferred by goannas. While our results were confounded by low sample sizes, drought conditions and a relatively short monitoring period, we did find weak evidence for trophic cascades after reintroducing predators. Monitoring over long periods is needed to better understand the ecological effects of predator reintroduction.

Phenology is critically important for understanding the impact of changing climate conditions on the timing of life-cycle events. Climate-induced shifts in plant phenology can affect food webs, reshape vegetation groups, alter ecosystem services and impact food security. Phenology aims to measure shifts in reproductive and vegetative cycles within and across ecological systems; however, the research field is challenged by variation in monitoring methods, landscape heterogeneity, data disparity and broad range climate conditions. Here we carried out a comprehensive systematic review on phenology responses of Myrtaceae to climate variability in Australia from 67 studies and spanning 58 years. Important phenophases under consideration include flowering, growth and germination. The review identified a geographical research focus in densely populated southeastern states and just 22% of the studies utilised a time series long enough to robustly detect phenological responses to climatic shifts (i.e., > 30 years). Although there was a strong emphasis on temperature and rainfall climate variables, the impact of compound events on phenology received little attention despite a projected increase in extreme conditions in future decades. Four priority areas are identified to address phenology research challenges, each of which is strengthened by rigorous citizen science: (1) greater focus on the impact of rainfall-related and extreme compound climate events; (2) expanded application of data generated through near-surface monitoring; (3) enhanced use of herbarium records to bridge data scale shortfalls; and (4) recognition of First Nations Peoples' perspectives and local area knowledge held by recurrent users of natural systems. These priority areas expand phenology research through innovative and adaptable methodological approaches to increase understanding of the impact of changing climate conditions on plant phenology.

Peatlands are globally significant ecosystems, influencing carbon and water cycles at local, regional and planetary scales, as well as harbouring a uniquely adapted biodiverse flora and fauna. However, peatlands in Oceania have received relatively little research or policy attention. This review aimed to document existing knowledge of peatlands in Oceania and identify gaps and opportunities to enhance their management to contribute to national and global outcomes for biodiversity conservation and carbon sequestration. We reviewed and synthesised existing published scientific literature, grey literature accessed via professional affiliations and, where written material was missing or sparse, shared and documented expert practitioner and professional experiences in peatlands across the Oceania region. We found that Oceania contains a diversity of peatlands spread across all five ecological zones from the tropics to temperate environments and from the lowlands up to mountain and alpine regions. There is a notable dominance of the Restionaceae family in the formation of peatlands in Oceania, in contrast to other regions where moss and tree species are recognised as the most important peat forming species. The knowledge gaps uncovered in this review are substantial. There is little documentation regarding peatlands of Pacific Island nations. Mapping is incomplete or out of date in many parts of Oceania and detailed understanding of ecohydrological function is rare in this region. The findings of this review highlight five opportunities nascent within Oceania's peatlands: (1) local and global carbon, biodiversity and water regulation benefits via restoration and protection; (2) partnerships between Indigenous and community groups and government; (3) South to South regional collaboration; and (4) global knowledge sharing including (5) support to implement existing international policies and agreements. Recommendations across the domains of research, management and policy outline seven key actions that could contribute towards realising the full potential of Oceania's peatlands, both in terms of their intrinsic value and ‘Natures Contributions to People’.

The expansion of human land use has led to significant loss of natural habitats. In forest plantations established in grassland ecosystems, remnants of native habitats persist as linear structures, such as roadsides, firebreaks, and stream margins, commonly referred to as ‘corridors’. Insects are highly sensitive to environmental changes, and their body size can serve as an indicator of habitat quality. We hypothesised that corridors within forest plantations that exhibit greater native vegetation cover, resembling natural environments, provide sufficient resources for insect development, resulting in increased insect biomass. According to the environmental filtering model, habitat characteristics in human-modified landscapes and biotic interactions act as filters, promoting the loss of certain species and convergence in functional traits. We posited that environmental filtering is the primary mechanism structuring flying insect assemblages in these corridors, and that its influence diminishes with increasing corridor width and native vegetation cover. To test this, we quantified insect biomass through body size and abundance and analyzed variation in body size among collected flying insects in forest plantation corridors and larger patches (representing the natural environment). Also, we measured vegetation cover and corridor width, and we evaluated their relationship with insect biomass and its components. Our results indicate that intensive land use impacts insect biomass primarily by influencing insect abundance: larger patches support greater insect biomass and abundance than forest corridors. Additionally, we observed that most corridors had less variation in insect body size than expected by chance, a pattern consistent with the environmental filtering hypothesis.

To conserve Darwin's fox (Lycalopex fulvipes, family Canidae), an endemic Chilean species and one of the most endangered canids in the world, it is essential to understand its potential habitat suitability, habitat nuclei and movement corridors to identify priority areas for conservation. To this end, we developed a habitat suitability modelling approach for the species, incorporating environmental covariates and occurrence records. The models were calibrated and evaluated using correlation analysis, variance inflation factor (VIF), regularisation, bootstrap, area under the curve (AUC) and true skill statistic (TSS). To assess the contribution of each covariate, we applied a Jackknife analysis. Habitat nuclei were identified and delineated by applying a threshold to the habitat suitability model and refining their extent using spatial layers relevant to Darwin's fox. Potential movement corridors were identified using a resistance-to-movement matrix derived from an analytic hierarchy process (AHP). The most influential variables were canopy cover and precipitation, with the highest habitat suitability concentrated in mountainous areas experiencing lower levels of human disturbance. We identified seven habitat nuclei and six corridors, connecting all nuclei, although some remained considerably more isolated. Our findings demonstrate that the study area contains critical sites possessing the necessary attributes to support effective conservation of the species' habitat.

Birds are essential in connecting conserved and restored habitats in anthropogenic landscapes, acting as ‘mobile links’ that enhance habitat connectivity. They contribute to key ecological functions that support habitat recovery. Despite their sensitivity to habitat changes, bird assemblages in restored landscapes show varied responses due to factors like the restoration technique employed. This study uses the species–habitat network approach to assess how different restoration techniques and bird functional traits influence bird habitat use and connectivity in the Atlantic Forest. We adapted network metrics—among-module connectivity and within-module degree (c- and z-scores, respectively)—to quantify how habitat types contribute to landscape connectivity and to assess how bird functional traits explain patterns of occupancy across restored fragments. We show that actively restored habitats tend to have more exclusive bird species compared to conserved forests, whereas naturally regenerated forests support a broader range of shared bird species. While active restoration often promotes species with specific habitat needs, it may have a more limited role in landscape connectivity, compared to natural regeneration, which better integrates habitat types. These findings suggest that combining active and passive restoration strategies can maximise landscape connectivity, with active restoration providing habitat for species with particular requirements and passive restoration enhancing broader ecosystem recovery through bird occupation. Additionally, our findings indicate that bird functional traits have low explanatory power for patterns of bird habitat use in restored landscapes, emphasising the value of a more detailed network approach that includes species-specific interactions. Still, the species–habitat network approach revealed key species that help connect different habitat types, highlighting the role of bird species in landscape cohesion. Future research should explore finer network resolutions and larger spatial scales to better capture species movement and habitat dynamics within restoration gradients.