Austral Ecology最新文献

Demographic studies are essential for understanding how species populations respond over time to environmental conditions and anthropogenic pressures. This knowledge is crucial for developing effective conservation and management strategies. The Arecaceae family (palms), comprising approximately 2500 species, plays significant ecological and socio-economic roles but faces constant threats due to land-use changes and harvesting. Although numerous demographic studies have been conducted, no comprehensive synthesis exists to identify gaps and achievements within this field for Arecaceae, which could guide future research efforts. This study provides an overview of current knowledge on Arecaceae demography. Through a systematic review, 59 demographic studies were identified, totaling 181 study cases. A total of 29 genera and 44 species were recorded, with Chamaedorea radicalis, a human-used species, the most frequently studied. Species classified as Least Concern in the IUCN Red List were the most commonly sampled. The Neotropical region had the highest representation, with Mexico, Colombia, and Brazil as the main contributors. In contrast, the Indo-Malayan biogeographic region, which harbours the highest palm species richness, had only one recorded demographic study. The Matrix Projection Model was the most widely used demographic analysis method, followed by the Integral Projection Model. The average sampling time was 2.43 years. Despite the substantial number of demographic studies on Arecaceae, significant gaps remain, particularly in regions and countries with higher species richness and among species classified as threatened. Future research should prioritise underrepresented taxa and regions, as well as long-term monitoring efforts to enhance conservation strategies.

The Amazon is recognised as one of the most conserved tropical rainforests in the world. However, along its peripheral agricultural frontiers, mammal assemblages are gradually being eroded due to deforestation of this large area known as the Arc of Deforestation, particularly along the Amazon's southeast. In this study, we aimed to expand on the knowledge of richness, composition, and defaunation of mammal assemblages in two priority protected areas for biodiversity in the region: Cristalino State Park (hereafter Cristalino) and Xingu State Park (hereafter Xingu). We used camera traps and line transects for data collection between 2020 and 2021. Our results demonstrated that both protected areas support rich assemblages of medium- and large-sized mammals within the south-central Amazon (Cristalino—32 species, Xingu—30 species). Due to the differing vegetation types between each park, the two mammal assemblages showed significant differences in species composition. Even with one of the highest biomasses of large ungulates (tapir and brocket deer) and apex predators (jaguar and puma) compared to other protected areas in south-central Amazon, both areas showed a high biomass defaunation index relative to these same areas. The result is largely driven by the low abundance of peccaries, especially Tayassu pecari. This could be one of the impacts of extensive human pressure caused by deforestation and degradation around and inside these protected areas. Both parks play an important role in the survival of threatened mammals, and in maintaining biodiversity and ecosystem functionality in the southern Amazon, helping to curb agricultural expansion into the interior of the Amazon rainforest.

In Australia, species declared as ‘extinct’ are afforded no legal protection, even after rediscovery, despite rediscovery being the most common reason for changes to extinct species' listing. Here we use the rediscovery of Atriplex acutiloba R.H.Anderson, an Australian arid zone plant species listed as extinct, to examine how species listing policies may inhibit conservation once a species is, at least on paper, declared extinct. We also provide previously unpublished ecological notes to help reduce taxonomic confusion and improve the veracity of future records of Atriplex acutiloba. We provide recommendations for provisional relisting or emergency revisions where rediscovered species were presumed extinct to ensure that necessary protections are afforded until dedicated reassessment can occur.

A 2024 paper in Science described the realised and potential thermal niches of 188 North American tree species in terms of mean annual temperature (MAT). Using PlantSearch data from outside species-native distributions, it was found that species potential niches displayed a ‘centrifugal organisation’ of thermal niches. As a result, ‘potential niches of cold-adapted species extend to warmer temperatures, whereas potential niches of warm-adapted species extend to cooler temperatures’. These patterns could have important implications for tree species management under climate change, and the study described here aimed to determine if similar patterns could be found with the MAT niches of eucalypt species. The realised niches of 48 eucalypt species and subspecies were assessed in terms of MAT range using maps from a 2016 book and 2022 paper as well as the Atlas of Living Australia (ALA). Potential niches for 44 species and subspecies were examined using ex situ data from the PlantSearch database of Botanic Gardens Conservation International (BGCI). Results from the study described here were less clear-cut than the North American study, but some similarities were found. For example, potential niches of cold-adapted species extended to warmer temperatures, whereas potential niches of warm-adapted species extended to cooler temperatures. In summary, there was some support for the conclusions of the North American study. However, data from arboreta and botanic gardens should be used with care or levels of species climatic tolerance may be exaggerated. The collation of data from commercial trials, which would be more representative of broadscale areas and could also include provenance as well as species information, is recommended.

Fish-habitat associations are fundamental ecological relationships characterising marine community assembly. The strength of fish-habitat associations can be indicative of ecosystem resilience, making them important benchmarks for ecological monitoring. These relationships are relatively unknown in mesophotic (30–150 m) marine systems due to the constraints of sampling in deeper waters. We aimed to assess fish-habitat associations in two unstudied no-take National Park Zones in the recently established Abrolhos Marine Park, Western Australia. We used the first baited remote underwater stereo-video systems (stereo-BRUVs) in this area to quantify demersal fish and benthic habitats between 33 and 154 m depth and modelled associations among fish species, traits and environmental covariates using Hierarchical Modelling of Species Communities (HMSC). Significant evidence of species-environment, trait-environment, and species-species associations was identified which may influence local community assembly. Benthic habitats explained 62.4% of the modelled variation in fish abundance, and 7 of the 21 modelled species showed strong statistical relationships with habitat, particularly macroalgae. The modelled species-environment relationships enabled us to infer the distribution of a subset of fish species across these understudied no-take zones. This study demonstrates the potential of discrete opportunistic studies using stereo-BRUVs for investigating the key drivers of community assembly in mesophotic marine environments. Our findings emphasise the importance of ongoing efforts to map and monitor benthic habitats and bathymetry as influential drivers of higher order species distribution beyond the coastal zone.

Fire is an important factor influencing the evolution, structure and composition of Australia's native vegetation. Australia's many fire-adapted species regenerate en masse after fire, with a proliferation of new epicormic shoots and seedlings. Given Austropuccinia psidii (myrtle rust) mainly infects new growth, post-fire emergence of new epicormic shoots and seedlings is ideal for the development of the disease, leading to further loss of plants along with subsequent increase of fungal inoculum in the region. Extreme fire events across New South Wales and Queensland in 2019–2020 and subsequent vegetation regeneration across a wide area provided ideal conditions for disease epidemics. Surveys for myrtle rust were conducted across rainforest, coastal heath and woodland environments from south-eastern NSW to south-east Queensland 6–12 months post-fire. Myrtle rust was identified in all regions and ecosystems surveyed apart from areas in south-eastern NSW. Of the 73 Myrtaceae species surveyed in areas other than southern NSW, 44 were found with myrtle rust symptoms, ranging from small spots and limited damage to severe blighting, dieback and death of reshooting trees and seedlings. Monitoring plots were established for some of the more susceptible species, with monthly assessments conducted to determine impact levels and decline rates. The most severely impacted species were Rhodamnia rubescens and Uromyrtus australis, with infections of reshoots causing dieback. Infection of Melaleuca quinquenervia and M. nodosa reshoots and seedlings impeded recovery of populations, causing seedling and tree deaths and reducing flower set and subsequent seed production.

Translocations are increasingly used to restore populations, yet seldom are simultaneous over large climate gradients into different latitudes, and rarely consider both a host and its parasites. Tuatara (Sphenodon punctatus) is a long-lived reptile endemic to Aotearoa New Zealand (NZ). Once found throughout NZ, tuatara populations are now sustained on offshore islands and increased through translocation, including to pest-free sanctuaries. Here, we study the simultaneous translocations of adult tuatara to four mainland sanctuaries a decade following release, investigating populations established both north and south of the founding population that span nearly 1000 km in latitude. We compared changes in body condition and snout-vent length (SVL) of tuatara, and abundance of a host-specific, ectoparasitic tick for tuatara among sites, plus evidence for survival and emergence of the next generation of tuatara. We found a general increase in SVL and maintenance of body condition between release in 2012 and 2023 at all sites, with some differences between males and females. However, tuatara at some sites showed more growth and/or higher body condition by 2023, particularly correlating with site temperature. Although ticks persisted on founding tuatara, there were fewer ticks on the next generation and those at the southern site. Evidence for a second generation of tuatara was also weakest at the southern site. This study shows that long-distance translocations north and south of a source population can yield promising outcomes for survival and growth of a long-lived reptile in current climates, though with differences in outcomes among sites.

Tropical dry forests (TDFs) have been altered by anthropogenic disturbances, particularly deforestation for pastures creation, which impacts plant and animal composition, abundance, and ecological processes. This study examined the spatio-temporal variation of fruit-feeding butterfly assemblage along an environmental gradient (forest interior, transition zone, and pasture) in TDFs at “Serra da Jacobina”, a mountain range 220 km long in Brazil. Butterflies were collected using 234 baited traps across nine transects in both the dry and rainy seasons. A total of 1091 individuals belonging to 35 species of the Nymphalidae family were sampled. Butterfly composition did not differ between environments or seasons, but forests showed higher abundance and richness, which were positively related to tree density. Species richness peaked in the rainy season, though abundance remained consistent. Eight species served as habitat indicators, with Hamadryas februa being the strongest indicator of old-growth forests; showing highest abundance in the forest interior and decreasing towards the pasture. Conversely, two species (Hamadryas feronia and Callicore sorana) showed the opposite pattern, predominating in pastures. Changes in land cover and tree density were key factors influencing butterfly assemblages. Longer pasture rotation and the preservation of native and fruit trees can help maintain insect diversity and ecosystem services, including those provided by fruit-feeding butterflies.

Community ecology explores the organisation and functioning of species assemblages shaped by historical, environmental and biotic processes. This review introduces community distribution models (CDMs), which extend species distribution models (SDMs) to higher ecological levels. CDMs integrate three key processes: (1) dispersal constraints, (2) environmental filters and (3) biotic drivers, while also incorporating metacommunity paradigms to explain community patterns. The review synthesises factors influencing community composition and identifies how CDMs can improve biodiversity predictions. We highlight the importance of environmental variables, biotic interactions and species traits and critically assess current modelling limitations. Functional traits, rather than species alone, are proposed as a more effective basis for modelling community dynamics, particularly in the context of climate change and habitat degradation. Finally, we advocate for integrative approaches combining correlative and mechanistic models to better capture community assembly across scales. CDMs hold great potential to address key ecological challenges, such as climate change impacts and conservation prioritisation. By advancing methodological frameworks and incorporating metacommunity theory, CDMs can provide deeper insights into emergent community properties and guide effective conservation strategies.