The good,the bad,and the ugly: which Australian terrestrial mammal species attract most research?

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Biases,gaps, and opportunities in mammalian extinction risk research

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Insular bats and research effort: a review of global patterns and priorities

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Global effort allocation in marine mammal research indicates geographical,taxonomic and extinction risk‐related biases

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Changes in the range of the medicinal herb Eriocaulon buergerianum Körnicke. (Eriocaulaceae) under climate change

• Eriocaulon buergerianum Körnicke. (Eriocaulaceae) is one of the most common and least expensive herbal medicines for eye disease. This species is facing potential threats from climate change. Insufficient biogeographic knowledge of this plant species can hinder its effective management for long‐term population survival.
• We integrated ecological niche modelling (Biomod2) with 70 records of E. buergerianum and eight environmental variables to estimate changes in distribution over time. A core area Zonation algorithm was introduced to identify conservation priority areas.
• Our results indicate that the range of E. buergerianum will likely decrease in the future: the overall range change on average is ?44.36 ± 21.56% (?3.70% to ?77.73%); values of range loss and range gain are 45.79 ± 20.30% (9.29–78.19%) and 1.43 ± 1.53% (0.18–5.59%), respectively. According to conservation priority analysis, the mandatory reserve (top 5%), negotiable reserve (0.95–0.9) and partial reserve (0.9–0.8) areas are 19,799, 19,799 and 39,597 km², respectively. The areas identified as conservation priority are located in the southeast, especially in northern Taiwan and the Wuyi Mountains.
• Based on these results, we suggest a re‐evaluation of the threatened status of this species, with a potential upgrade to the vulnerable (VU) category. To overcome the adverse conditions faced by populations of E. buergerianum in China, we propose a multi‐faceted conservation strategy involving more complete resource assessment, a monitoring system, medical research focused on revealing medicinal components or substitutes, and a regional development plan that considers both wildlife and socio‐economic issues.

     

Understanding trends in biological invasions by introduced mammals in southern South America: a review of research and management

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Wilderness and future conservation priorities in Australia

Aim Most approaches to conservation prioritization are focused on biodiversity features that are already threatened. While this is necessary in the face of accelerating anthropogenic threats, there have been calls to conserve large intact landscapes, often termed ‘wilderness’, to ensure the long‐term persistence of biodiversity. In this study, we examine the consequences of directing conservation expenditure using a threat‐based framework for wilderness conservation. Location The Australian continent. Methods We measured the degree of congruence between the extent of wilderness and the Australian protected area network in 2000 and 2006, which was established using a threat‐based systematic planning framework. We also assessed priority areas for future reserve acquisitions identified by the Australian government under the current framework. Results In 2000, 14% of Australia’s wilderness was under formal protection, while the protected area network covered only 8.5% of the continent, suggesting a historical bias towards wilderness protection. However, the expansion of the reserve system from 2000 to 2006 was biased towards non‐wilderness areas. Moreover, 90% of the wilderness that was protected over this period comprised areas not primarily designated for biodiversity conservation. We found a significant (P < 0.05) negative relationship between bioregions considered to be a priority for future reserve prioritization and the amount of wilderness they contain. Main conclusions While there is an urgent need to overcome past biases in reserve network design so as to better protect poorly represented species and habitats, prioritization approaches should not become so reactive as to ignore the role that large, intact landscapes play in conserving biodiversity, especially in a time of human‐induced climate change. This can be achieved by using current or future threats rather than past threats to prioritize areas, and by incorporating key ecological processes and costs of acquisition and management within the planning framework.     

Status and challenges for conservation of small mammal assemblages in South America

South America spans about 44° latitude, covers almost 18 million km², and is second only to Africa in continental mammal species richness. In spite of this richness, research on the status of this fauna and on the nature and magnitude of contemporary threats remains limited. Distilling threats to this diverse fauna at a continental scale is challenging, in part because of the limited availability of rigorous studies. Recognizing this constraint, we summarize key threats to small mammals in South America, emphasizing the roles of habitat loss and degradation, direct persecution, and the increasing threat of climate change. We focus on three regional ‘case studies’: the tropical Andes, Amazonia and adjacent lowland regions, and the southern temperate region. We close with a brief summary of recent findings at our long‐term research site in north‐central Chile as they pertain to projected threats to this fauna. Habitat alteration is a pervasive threat that has been magnified by market forces and globalization (e.g. extensive agricultural development in Amazonia), and threatens increasing numbers of populations and species. Climate change poses even greater threats, from changes in rainfall and runoff regimes and resulting changes in vegetative structure and composition to secondary influences on fire dynamics. It is likely that many changes have yet to be recognized, but existing threats suggest that the future may bring dramatic changes in the distribution of many mammal taxa, although it is not clear if key habitat elements (vegetation) will respond as rapidly as climatic factors, leading to substantial uncertainty. Climate change is likely to result in ‘winners’ and ‘losers’ but available information precludes detailed assessment of which species are likely to fall into which category. In the absence of long‐term monitoring and applied research to characterize these threats more accurately, and to develop strategies to reduce their impacts, managers already are being faced with daunting challenges. As the line between ‘pure’ and ‘applied’ research blurs in the face of converging interests of scientists and society we hope that solutions to these critical issues will be incorporated in addressing anticipated conservation crises.     

The Neotropical otter Lontra longicaudis: a comprehensive update on the current knowledge and conservation status of this semiaquatic carnivore

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What do we know about armadillos? An analysis of four centuries of knowledge about a group of South American mammals,with emphasis on their conservation

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Ricochet pollination in Senna (Fabaceae) – petals deflect pollen jets and promote division of labour among flower structures

• Naturalists Fritz and Hermann Müller hypothesised that heteranthery often leads to a division of labour into ‘feeding’ and ‘pollinating’ stamens; the latter often being as long as the pistil so as to promote successful pollination on the bees’ back. In many buzz‐pollinated species of Senna, however, the so‐called pollinating stamens are short and not level with the stigma, raising the question of how pollen is shed on the bees’ back. Here we explore a mechanism called ‘ricochet pollination’. We test whether division of labour is achieved through the interaction between short lower stamens and strongly concave ‘deflector petals’.
• We studied the arrangement and morphology of the floral organs involved in the ricochet pollination, functioning of the flowers through artificial sonication and observed the interactions between bees and flowers in the field.
• The middle stamens are adapted to eject pollen downwards, which can be readily collected on the bee mid legs. Most of the pollen is ejected towards the deflector petal(s). Pollen from this set of stamens is more likely to contribute to pollination. The pollen grains seem to ricochet multiple times against the deflector petals to eventually reach the bee's back.
• The pollen ricochet mechanism promotes a division of labour by involving additional floral organs, such as petals, reinforcing the Müllers’ division‐of‐labour hypothesis. However, alternative, non‐multiexclusive hypotheses could be explored in genus Senna and other angiosperm species.

     

Identifying species at extinction risk using global models of anthropogenic impact

The International Union for Conservation of Nature Red List of Endangered Species employs a robust, standardized approach to assess extinction threat focussed on taxa approaching an end‐point in population decline. Used alone, we argue this enforces a reactive approach to conservation. Species not assessed as threatened but which occur predominantly in areas with high levels of anthropogenic impact may require proactive conservation management to prevent loss. We matched distribution and bathymetric range data from the global Red List assessment of 632 species of marine cone snails with human impacts and projected ocean thermal stress and aragonite saturation (a proxy for ocean acidification). Our results show 67 species categorized as ‘Least Concern’ have 70% or more of their occupancy in places subject to high and very high levels of human impact with 18 highly restricted species (range <100 km²) living exclusively in such places. Using a range‐rarity scoring method we identified where clusters of endemic species are subject to all three stressors: high human impact, declining aragonite saturation levels and elevated thermal stress. Our approach reinforces Red List threatened status, highlights candidate species for reassessment, contributes important evidential data to minimize data deficiency and identifies regions and species for proactive conservation.     

Spread of an introduced parasite across the Hawaiian archipelago independent of its introduced host

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Habitat filtering and adult dispersal determine the taxonomic composition of stream insects in an urbanizing landscape

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Occurrence of two different development patterns in Lobesia botrana (Lepidoptera: Tortricidae) larvae during the second generation

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Development and field validation of a regional,management‐scale habitat model: A koala Phascolarctos cinereus case study

Species distribution models have great potential to efficiently guide management for threatened species, especially for those that are rare or cryptic. We used MaxEnt to develop a regional‐scale model for the koala Phascolarctos cinereus at a resolution (250 m) that could be used to guide management. To ensure the model was fit for purpose, we placed emphasis on validating the model using independently‐collected field data. We reduced substantial spatial clustering of records in coastal urban areas using a 2‐km spatial filter and by modeling separately two subregions separated by the 500‐m elevational contour. A bias file was prepared that accounted for variable survey effort. Frequency of wildfire, soil type, floristics and elevation had the highest relative contribution to the model, while a number of other variables made minor contributions. The model was effective in discriminating different habitat suitability classes when compared with koala records not used in modeling. We validated the MaxEnt model at 65 ground‐truth sites using independent data on koala occupancy (acoustic sampling) and habitat quality (browse tree availability). Koala bellows (n = 276) were analyzed in an occupancy modeling framework, while site habitat quality was indexed based on browse trees. Field validation demonstrated a linear increase in koala occupancy with higher modeled habitat suitability at ground‐truth sites. Similarly, a site habitat quality index at ground‐truth sites was correlated positively with modeled habitat suitability. The MaxEnt model provided a better fit to estimated koala occupancy than the site‐based habitat quality index, probably because many variables were considered simultaneously by the model rather than just browse species. The positive relationship of the model with both site occupancy and habitat quality indicates that the model is fit for application at relevant management scales. Field‐validated models of similar resolution would assist in guiding management of conservation‐dependent species.     

Mapping tree species vulnerability to multiple threats as a guide to restoration and conservation of tropical dry forests

Understanding the vulnerability of tree species to anthropogenic threats is important for the efficient planning of restoration and conservation efforts. We quantified and compared the effects of future climate change and four current threats (fire, habitat conversion, overgrazing and overexploitation) on the 50 most common tree species of the tropical dry forests of northwestern Peru and southern Ecuador. We used an ensemble modelling approach to predict species distribution ranges, employed freely accessible spatial datasets to map threat exposures, and developed a trait‐based scoring approach to estimate species‐specific sensitivities, using differentiated trait weights in accordance with their expected importance in determining species sensitivities to specific threats. Species‐specific vulnerability maps were constructed from the product of the exposure maps and the sensitivity estimates. We found that all 50 species face considerable threats, with an average of 46% of species’ distribution ranges displaying high or very high vulnerability to at least one of the five threats. Our results suggest that current levels of habitat conversion, overexploitation and overgrazing pose larger threats to most of the studied species than climate change. We present a spatially explicit planning strategy for species‐specific restoration and conservation actions, proposing management interventions to focus on (a) in situ conservation of tree populations and seed collection for tree planting activities in areas with low vulnerability to climate change and current threats; (b) ex situ conservation or translocation of populations in areas with high climate change vulnerability; and (c) active planting or assisted regeneration in areas under high current threat vulnerability but low climate change vulnerability, provided that interventions are in place to lower threat pressure. We provide an online, user‐friendly tool to visualize both the vulnerability maps and the maps indicating priority restoration and conservation actions.     

Do understorey or overstorey traits drive tree encroachment on a drained raised bog?

• One of the most important threats to peatland ecosystems is drainage, resulting in encroachment of woody species. Our main aim was to check which features – overstorey or understorey vegetation – are more important for shaping the seedling bank of pioneer trees colonising peatlands (Pinus sylvestris and Betula pubescens). We hypothesised that tree stand parameters will be more important predictors of natural regeneration density than understorey vegetation parameters, and the former will be negatively correlated with species diversity and richness and also with functional richness and functional dispersion, which indicate a high level of habitat filtering.
• The study was conducted in the ‘Zielone Bagna’ nature reserve (NW Poland). We assessed the structure of tree stands and natural regeneration (of B. pubescens and P. sylvestris) and vegetation species composition. Random forest and DCA were applied to assess relationships between variables studied.
• Understorey vegetation traits affected tree seedling density (up to 0.5‐m height) more than tree stand traits. Density of older seedlings depended more on tree stand traits. We did not find statistically significant relationships between natural regeneration densities and functional diversity components, except for functional richness, which was positively correlated with density of the youngest tree seedlings.
• Seedling densities were higher in plots with lower functional dispersion and functional divergence, which indicated that habitat filtering is more important than competition. Presence of an abundant seedling bank is crucial for the process of woody species encroachment on drained peatlands, thus its dynamics should be monitored in protected areas.