Focal Species Research Articles

Strangers like me: birds respond equally to a familiar and an unfamiliar sentinel species' alarm calls, but respond less to non‐core and non‐sentinel's alarm calls

Alarm signals have evolved to communicate imminent threats to conspecifics but animals may also perceive other species' alarm displays to obtain adaptive information. In birds, mixed‐species foraging flocks are often structured around a focal sentinel species, which produces reliable alarm calls that inform eavesdropping non‐sentinel heterospecifics about predation risk. Ongoing work has revealed that several species can recognize the alarm calls of certain sentinel species even without prior encounters, including when these are from distant biogeographic regions. Similar work has yet to examine whether naive subjects' responses to unfamiliar sentinel alarm calls differ from responses to non‐sentinel alarm calls. Here we played the alarm calls of three subtropical Asian bird species that participate in mixed species flocks, to temperate North American birds. Birds responded most to the alarm call of an allopatric core sentinel and a local sympatric sentinel control species, less so to an allopatric non‐core sentinel, and least so to an allopatric non‐sentinel and a negative control stimulus. These patterns provide evidence that broad phylogenetic and geographic recognition is a pertinent aspect of sentinel alarm calls in general.

Turnover importance: Operationalizing beta diversity to quantify the generalism continuum

Abstract Generalization is difficult to quantify, and many classifications exist. A beta diversity framework can be used to establish a numeric measure of generalist tendencies that jointly describes many important features of species interactions, namely spatiotemporal heterogeneity. This framework is promising for studying generalized symbiotic relationships of any form. We formulated a novel index, turnover importance (T). T describes spatiotemporal heterogeneity in interactor assemblages, an inherent feature of generalist relationships that is not captured by available metrics. We simulated the behaviour of T relative to other available metrics, calculated T for native North American orchid‐insect relationships, and tested correlations between T and eco‐geographic variables. We performed case studies to demonstrate applications of T for conservation and eco‐evolutionary studies. T behaves predictably across simulations, and dynamically interacts with site number, gamma diversity, and species range sizes. T is moderately sensitive to sampling depth. Orchids with higher T scores occupy larger ranges and broader climatic niches. Alternative interactor‐specific measures of generalism are best employed for local‐level community networks over short timespans. While these interactor metrics can assess use versus availability in local communities, T can be used to measure spatiotemporal patterns of variation in interactor assemblages across a focal species' range. This study provides a roadmap for future work focused on better understanding the patterns and consequences of generalized relationships.

The International Union for Conservation of Nature Red List does not account for intraspecific diversity

Abstract The International Union for Conservation of Nature (IUCN) Red List identifies threatened and endangered species and is a key instrument in global biodiversity conservation efforts. Our understanding of the structure and value of genetic biodiversity below the species level is rapidly increasing. Nonetheless, the IUCN assessment criteria overlook genetic variation within species. Here, we address this blind spot and discuss the principles of species conservation status classification relative to intraspecific biodiversity. We focus on coastal species, which thrive in heterogeneous environments known to drive genetic differentiation. The focal example species, Atlantic cod and sugar kelp, have contrasting life histories, are ecologically and economically important constituents of the coastal ecosystem, and are currently not classified as threatened in Norway and Canada. We expose important variation in population structure, the presence of ecotypes and genetic-environment covariation, as well as loss of ecotypes that threatens the conservation of these species. Because the genetic makeup of species directly influences their resilience, omitting this information from conservation status assessments can result in loss of adaptive capacity to future stressors, such as climate change. Consequently, recognizing and preserving intraspecific variation emerges as vital for species’ abilities to adapt to and survive in future ocean conditions.

Genetic structure and landscape effects on gene flow in the Neotropical lizard Norops brasiliensis (Squamata: Dactyloidae).

One key research goal of evolutionary biology is to understand the origin and maintenance of genetic variation. In the Cerrado, the South American savanna located primarily in the Central Brazilian Plateau, many hypotheses have been proposed to explain how landscape features (e.g., geographic distance, river barriers, topographic compartmentalization, and historical climatic fluctuations) have promoted genetic structure by mediating gene flow. Here, we asked whether these landscape features have influenced the genetic structure and differentiation in the lizard species Norops brasiliensis (Squamata: Dactyloidae). To achieve our goal, we used a genetic clustering analysis and estimate an effective migration surface to assess genetic structure in the focal species. Optimized isolation-by-resistance models and a simulation-based approach combined with machine learning (convolutional neural network; CNN) were then used to infer current and historical effects on population genetic structure through 12 unique landscape models. We recovered five geographically distributed populations that are separated by regions of lower-than-expected gene flow. The results of the CNN showed that geographic distance is the sole predictor of genetic variation in N. brasiliensis, and that slope, rivers, and historical climate had no discernible influence on gene flow. Our novel CNN approach was accurate (89.5%) in differentiating each landscape model. CNN and other machine learning approaches are still largely unexplored in landscape genetics studies, representing promising avenues for future research with increasingly accessible genomic datasets.

Divergent reproductive responses of Caatinga dry forest plants to leaf-cutting ant herbivory

Herbivory is one of the key processes shaping life history traits linked to plant fitness and the leaf-cutting ants are amongst the most voracious and polyphagous herbivores of the Neotropics. They extensively harvest aboveground plant parts to grow their symbiotic fungus, including vegetative and reproductive tissues. Although leaf-cutting ant herbivory is expected to reduce plant reproductive success, the potentially different outputs of damage to vegetative and reproductive parts are still poorly known. This study investigates the influence of Atta opaciceps herbivory on the reproductive success of three plant species native to the Caatinga dry forest: Croton argyrophylloides (Euphorbiaceae), Cenostigma pyramidale, and Indigofera suffruticosa (Leguminosae). We selected 10 adult and active nests of A. opaciceps based on the presence of individuals of the three focal plant species in their vicinity. For each colony, we marked four individuals of each plant species (totaling 12 individuals per colony), which were then subjected to one of four herbivory treatments: (1) ant herbivory on both reproductive and vegetative parts, (2) manually simulated herbivory on the reproductive parts alone, (3) ant herbivory exclusively on vegetative parts, and (4) no herbivory. From January to April 2020, we monitored all 120 individuals, recording the number of inflorescences, flower buds, flowers, fruits, and the proportion of flowers maturing into fruits (fruit set, as a proxy of reproductive success). Results revealed variations in reproductive structure production and divergent responses to leaf-cutting ant herbivory among our focal species. In terms of inflorescence, flower bud production, and fruit set C. argyrophylloides showed reduced numbers when subjected to higher levels of total herbivory (reproductive and vegetative parts), but increased inflorescence and flower bud production when plants suffered only leaf damage. Cenostigma pyramidale individuals under partial herbivory displayed lower flower bud numbers than protected ones. In contrast, I. suffruticosa displayed conflicting results, with fully exposed plants producing more inflorescences than partially exposed counterparts and more flowers than leaf-damaged and protected individuals. Despite the varied effects on different plant parts across all three study species, the overall reproductive success (i.e. fruit set) of only one species (C. argyrophylloides) was significantly reduced by leaf-cutting ant herbivory. The resilience of the two other plant species to leaf-cutting ant pressure may be attributed to compensatory mechanisms, shedding light on the intricate interplay between herbivores and plants in the Caatinga dry forest. As leaf-cutting ants proliferate in response to anthropogenic disturbances, the patterns described in this study may become more pronounced, potentially affecting the organization of plant communities in the Caatinga dry forest.

Optimised PCR assays for detecting elusive waterfowl from environmental DNA.

For many aquatic and semiaquatic mammal, amphibian and fish species, environmental DNA (eDNA) methods are employed to detect species distribution and to monitor their presence, but eDNA is much less employed for avian species. Here, we developed primers for the detection of true geese and swan species using eDNA and optimised a PCR protocol for eDNA. We selected taiga bean goose (Anser fabalis fabalis) as our focal (sub)species and sampled water from lakes, from which the presence of taiga bean goose was visually confirmed. To test, if taiga bean goose DNA could be detected among DNA of other goose species, we similarly sampled eDNA from a zoo pond housing several Anatidae species. We were able to detect taiga bean goose DNA in all but one of the tested lakes, including the zoo pond. The primers developed are not species-specific, but rather specific to the genus Anser, due to the close relatedness of Anser species, which prevented the development of species-specific primers and the use of, for example, quantitative PCR. We also developed eDNA primers for Branta species and Cygnus species and tested these primers using the same samples. Canada goose (B. canadensis) and barnacle goose (B. leucopsis) DNA were only detected in the zoo pond (in which they were present), as the sampled natural lakes fall outside the range of these species. We detected whooper swan (C. cygnus) DNA in three lakes and the zoo pond (in which the species was present). The eDNA method presented here provides a potential means to monitor elusive goose species and to study the co-occurrence of large waterfowl.

Integrating presence‐only and detection/non‐detection data to estimate distributions and expected abundance of difficult‐to‐monitor species on a landscape‐scale

Abstract Estimating species distribution and abundance is foundational to effective management and conservation. Using an integrated species distribution model that combines presence‐only data from various sources with detection/non‐detection data from structured surveys, we estimated the distribution and expected abundance of three difficult‐to‐monitor mammals of management concern across New York State, namely, coyotes (Canis latrans), bobcats (Lynx rufus) and black bears (Ursus americanus). Three distinct landscape‐scale camera trap surveys provided detection/non‐detection data over 9 years between 2013 and 2021, and we augmented those data with incidental records of our focal species from public repositories. We used an inhomogeneous Poisson point process to construct an integrated model that fit both data types simultaneously. We demonstrate a simple application of spatial point density of all species records in the accessed public databases to inform the thinning process to account for unknown spatial sampling in the presence‐only data, often referred to as the ‘magic covariate’. Using this approach, we examine habitat associations and provide spatially explicit estimates in expected abundance across the entirety of New York State for all three focal species. As expected, coyotes were the most widely distributed and abundant species, with a strong positive association with agricultural land uses. Bobcats exhibited low expected abundance throughout the state and showed positive associations with deciduous forest and forest edge, and a negative association with road density. Finally, we observed considerable spatial variation in abundance of black bears with expected abundance increasing in association with various forest cover and composition covariates and decreasing with crop cover. We present insights into habitat associations and spatial variation in abundance, and provide management implications for each of the species of interest. Synthesis and applications. Our integrated modelling method allows for managers to use citizen sightings combined with detection/non‐detection surveys to estimate robust indices of abundance for both high‐ and low‐density, and wide‐spread versus patchily distributed species. Through comparison with previous studies, we highlight how broad‐scale programmes, such as the statewide efforts to estimate species distributions undertaken here, can benefit substantively from integrated models that leverage additional data (here, incidental records) from a larger region of space, and thus capture more landscape heterogeneity than is plausible within formalized surveys alone.

Proposed spatial decision support system for delineating ecological corridors in green infrastructure planning constrained by lack of data: a case study in Galicia, Spain

AbstractIn response to the constant loss of biodiversity in European ecosystems, which is partly due to the impacts of climate change, the European Commission urges member states to include Green Infrastructure (GI) in their land-use plans. However, although the European Commission establishes the fundamental principles to be applied, the ambiguity of some terms generates a certain degree of complexity regarding the delineation of GI elements, especially Ecological Corridors (ECs). Thus, a straightforward methodology for delineating GI elements is required. Here, we propose a Spatial Decision Support System (SDSS) that could help non-expert planners identify areas with a high potential to function as ECs and that could thus facilitate the inclusion of these areas in regional GI plans. Probability distribution maps were constructed by fitting a maximum entropy model (MaxEnt) to publicly available data on selected focal species. The maps were combined with other variables that negatively affect species mobility and later inserted in a graph theory tool to determine the least-cost path that would serve as the basis for delineating ECs. The method was applied to the design of an EC network in Galicia (NW Spain), and use of the system as a tool to help spatial decision-making was evaluated. Despite some limitations, the method yielded promising results that could help non-expert planners to establish the basis for delineating EC networks and other GI elements.

Wildlife Conservation on Private Land: A Social-Ecological Systems Study.

As human activity accelerates the global crisis facing wildlife populations, private land conservation provides an example of wildlife management challenges in social-ecological systems. This study reports on the research phase of 'WildTracker' - a co-created citizen science project, involving 160 landholders across three Tasmanian regions. This was a transdisciplinary collaboration between an environmental organisation, university researchers, and local landholders. Focusing on mammal and bird species, the project integrated diverse data types and technologies: social surveys, quantitative ecology, motion sensor cameras, acoustic recorders, and advanced machine-learning analytics. An iterative analytical methodology encompassed Pearson and point-biserial correlation for interrelationships, Non-Metric Multidimensional Scaling (NMDS) for clustering, and Random Forest machine learning for variable importance and prediction. Taken together, these analyses revealed complex relationships between wildlife populations and a suite of ecological, socio-economic, and land management variables. Both site-scale habitat characteristics and landscape-scale vegetation patterns were useful predictors of mammal and bird activity, but these relationships were different for mammals and birds. Four focal mammal species showed variation in their response to ecological and land management drivers. Unexpectedly, threatened species, such as the eastern quoll (Dasyurus viverrinus), favoured locations where habitat was substantially modified by human activities. The research provides actionable insights for landowners, and highlights the importance of 'messy,' ecologically heterogeneous, mixed agricultural landscapes for wildlife conservation. The identification of thresholds in habitat fragmentation reinforced the importance of collaboration across private landscapes. Participatory research models such as WildTracker can complement efforts to address the wicked problem of wildlife conservation in the Anthropocene.

The effects of fire on large‐ and medium‐sized mammal communities: what do we know? A review

Abstract Large‐ and medium‐sized mammals play a unique role in ecosystem dynamics. They can change the physical and biotic landscape by altering the flow of resources among trophic levels, thereby affecting ecosystem functioning. Although the effects of fire on some ungulates have been well studied, data gaps exist for many species, including canids, felids, mustelids and ursids among others. To address this knowledge gap, we conducted a literature review to synthesize what is known about large and medium mammal responses to fire, including communities, species richness and species interactions in connection with fire. Twenty‐seven large and medium mammal species were studied. Fifty percent of the studies examined ungulates, far exceeding studies of other trophic levels. Eighty‐six percent were conducted on large mammals with significantly fewer studies on medium‐sized mammals. Only four studies examined multiple species responses to fire. Results indicated that fire had a largely positive effect on large‐ and medium‐sized mammals. However, considerable heterogeneity exists within and among taxa. Most fire research has been conducted on focal species rather than on biodiversity, and a large data gap exists on the interactions within or among large‐ and medium‐sized mammals. Forest management focus is changing from fire suppression to reinstating natural fire regimes. Effectiveness monitoring programmes will be needed to test the efficacy of restoration strategies in mammalian communities.

Genomics of a novel ecological phase shift: the case of a ‘weedy’ Montipora coral in Ulithi, Micronesia

AbstractLocal and global ecological stressors are leading to increased documentation of phase shifts in coral reefs from healthy stony corals to macrophytes. In more rare cases, phase shifts result in sponge, zoantharian or other dominant species. In Ulithi Atoll, Federated States of Micronesia, we have documented an unusual phase shift from reefs with a diverse stony coral assemblage to reefs dominated by a single species of stony coral: Montipora sp.—a coral-to-coral phase shift. This monospecific type of reef lowers fish diversity and biomass, impacting both ecological integrity, and livelihoods of reef-dependent human communities. In this study, we used a genomic approach to characterize such a reef. We assembled a de-novo reference genome and used RAD seq data with thousands of SNPs to determine if different reefs result from sexual or asexual reproduction, if weedy Montipora fragments are transported between islands by human activities, and if there is evidence of natural selection on specific genotypes, thus favoring spreading success. We found that sexual reproduction is predominant in the focal species, that there is no evidence of human-mediated spread, and that some genomic regions might be under selection. While such results eliminate a number of spreading hypotheses, more precise dispersal maps will be important to determine the tempo and mode of ‘invasion’ of Montipora in Ulithi Atoll. This study shows that selection and adaptation may be contributing to the success of a stony coral (e.g., Phase shift). While a stony coral may be successful in a disturbed environment, it does not necessarily provide the type of habitat that is conducive to high fish biomass and coral diversity. These results serve as a cautionary tale for restoration efforts that focus on single species coral resilience rather than ecosystem function.

A price on their heads? Assessing foreign demand as a driver of hornbill hunting in Cameroon

Unsustainable hunting to supply wildlife markets is a global threat to bird species and a key driver of biodiversity declines across Africa. Despite well-documented negative impacts of wildlife trade on many bird species, such as Asian hornbills and African vultures, its consequences for African hornbills remain poorly understood. Here, we use data from both online trade and interviews with hunters in Cameroon to investigate the implications of foreign demand for African hornbills, using a twofold approach. First, we explored factors associated with the prices of hornbill skulls, the most heavily traded and expensive hornbill products, in online markets. Second, we examined the relationship between hunting pressure and market demand using semi-structured interviews with hornbill hunters and traders in Cameroon. In our online sales analysis, we considered factors including numbers of sales, species conservation status, Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) listing, body size, sex, and skull length (including bill and casque). In addition, we considered the number of sound recordings available for focal species, as this factor is highly correlated with species range size and may serve as a proxy for detectability in the field. We then used generalized linear mixed-effects models (GLMM) to identify variables closely associated with the prices of hornbill skulls online. Generalized linear models (GLM) were used to examine the relationship between hunting pressure and the local and foreign demands in Cameroon. We found that online trade included skulls and other products from 20 African and five Asian hornbill species, the latter of which were all CITES-listed. The median online price for a hornbill skull was £117. Nearly half (nine out of 20) of the African hornbill species found in online trade were native to Cameroon. The three most heavily traded species—Yellow-casqued Hornbill (Ceratogymna elata), Black-casqued Hornbill (C. atrata), and White-thighed Hornbill (Bycanistes albotibialis)—accounted for 66% of online hornbill products. Larger-bodied hornbill species classified as threatened, subject to CITES regulations, and species with higher numbers of sound recordings available tended to command higher prices online and thus likely face higher hunting pressure. We also found that foreign demand has a significant impact on hornbill hunting pressure, particularly among younger hunters. Approximately 73% of Cameroonian hunters interviewed targeted hornbills, with 91% of these motivated to acquire hornbill heads for trade, and 98% intending to sell their products to foreign buyers. Our findings highlight the urgent need to address the negative impacts of international wildlife trade and implement measures to protect African hornbill populations from increasing threats of overexploitation.

Unravelling the biogeographic determinants of tree growth sensitivity to freeze and drought in Canada's forests

Abstract The evolutionary dynamics of tree species are influenced by their specific climatic environments, and their ability to persist is determined by adaptive strategies such as broad climate tolerance, phenotypic plasticity or genetic differentiation. Biogeographical predictions indicate that populations located at the edges of their ranges are more likely to experience heightened vulnerability to climatic fluctuations due to approaching tolerance limits. However, if local phenotypic acclimation or genetic adaptation has taken place, trees near the edge of their range could demonstrate comparable sensitivity to freeze and drought as the rest of the sampled population. Nevertheless, there remains uncertainty regarding the extent of developmental and evolutionary adjustments in climate sensitivity across the entire ranges of many tree species. Here, we document the biogeography of tree growth sensitivity to freeze and soil water and vapour pressure deficits during 1950–2018 using an extensive multi‐species tree‐ring dataset of 35,784 trees at 4535 sites covering boreal, temperate conifer and temperate deciduous forests of Canada. We quantify the relationships between tree radial growth increment and seasonal climate variables and explore factors driving the observed patterns of annual growth and climate sensitivity such as species, regional climate and local site conditions, and tree age and size. Freeze and drought had widespread impacts on tree growth that were contingent on the presence of focal species in interaction with tree size. An indirect growth thermal limitation towards cold/wet edges, occurring through the site moisture conditions, was observed in seven widespread species (e.g. Picea glauca, Picea mariana and Larix laricina). Moreover, six species had negative drought impacts more strongly expressed towards their warm/dry edges (e.g. Abies balsamea, Betula papyrifera and Pseudotsuga menziesii). However, widespread Picea, Pinus and Populus species showed no indication of increased sensitivity to soil water conditions at these edges. Synthesis. Our findings support the idea of evolutionary or acclimatization adjustments in the development of populations in response to long‐term climate conditions experienced in their respective locations. This underscores the importance of incorporating phenotypic and genomic data into future analyses of climate change impacts, which would enhance our ability to predict potential ecological shifts.

Chaotic turnover of rare and abundant species in a strongly interacting model community

The composition of ecological communities varies not only between different locations but also in time. Understanding the fundamental processes that drive species toward rarity or abundance is crucial to assessing ecosystem resilience and adaptation to changing environmental conditions. In plankton communities in particular, large temporal fluctuations in species abundances have been associated with chaotic dynamics. On the other hand, microbial diversity is overwhelmingly sustained by a "rare biosphere" of species with very low abundances. We consider here the possibility that interactions within a species-rich community can relate both phenomena. We use a Lotka-Volterra model with weak immigration and strong, disordered, and mostly competitive interactions between hundreds of species to bridge single-species temporal fluctuations and abundance distribution patterns. We highlight a generic chaotic regime where a few species at a time achieve dominance but are continuously overturned by the invasion of formerly rare species. We derive a focal-species model that captures the intermittent boom-and-bust dynamics that every species undergoes. Although species cannot be treated as effectively uncorrelated in their abundances, the community's effect on a focal species can nonetheless be described by a time-correlated noise characterized by a few effective parameters that can be estimated from time series. The model predicts a nonunitary exponent of the power-law abundance decay, which varies weakly with ecological parameters, consistent with observation in marine protist communities. The chaotic turnover regime is thus poised to capture relevant ecological features of species-rich microbial communities.

Effects of human disturbance on detectability of non-breeding birds in urban green areas

Animals adapted to disturbed habitats have evolved multiple behavioural strategies, spanning from hiding to displacing to less disturbed microhabitats. Urban areas pose new evolutionary challenges since animals often need to deal with novel environmental conditions. In this context, urban parks may constitute biodiversity hotspots within the concrete jungle. Nonetheless, the recent increase in recreational activities in urban parks potentially puzzles the ability of urban-dwelling animals to exploit these environments. In this study, we evaluated the effect of human disturbance and other contextual variables on the activity patterns of four bird species commonly found in European urban parks, covering a wide range of ecological characteristics: the blackbird (Turdus merula), the hooded crow (Corvus cornix), the Eurasian robin (Erithacus rubecula), and the wood pigeon (Columba palumbus). We performed repeated counts of these bird species in six urban parks in northern Italy and we fitted Bayesian N-mixture models to estimate the relationship between detection probability and human disturbance (number of people present in the park), phenology (date and time of the day), and weather conditions (temperature and precipitation). For all the species but the blackbird, we found a negative relationship between the number of people present in the park and the detection probability of the focal species. We also found species-specific effects of both phenology and weather conditions on the detection probability. Our results suggest that urban dwelling species can finely modulate their activity patterns in response to the level of human disturbance, suggesting a possible key role of behavioural phenotypic plasticity. Furthermore, uncovering patterns of detectability of urban fauna can help in planning biodiversity monitoring and conservation, as it provides useful information to carry out surveys when the probability of detecting individuals is highest, optimising resource investments and reliability of biodiversity estimates.

Are wading birds the ideal focal species for broader bird conservation? A cost-effective approach to ecological network planning

Focal species play a crucial role in planning ecological networks (ENs). Despite the finding that ENs designed for a specific focal species can yield benefits for associated communities, current practices of applying individual focal species have faced criticism for oversimplifying intricate ecosystems. Besides, the aggregation of ENs for individual species has been demonstrated as ineffective and costly. To improve cost-effectiveness, species with similar habitat preferences are typically conserved using shared strategies. Thus, drawing from the habitat preference of wading birds for blue and green spaces, we hypothesized that an EN for wading birds may benefit co-existing water and forest birds that prefer blue or green spaces. To validate this hypothesis, we conducted our study in the Yangtze River Delta’s Ecological Green Integration Demonstration Zone. We simulated six scenarios S1-S6 to compare the cost-effectiveness of focal species networks, respectively for water, forest, and wading birds in the S2-S4, with the aggregate networks in the S5-S6. During ENs’ construction, we employed the InVEST Habitat Quality model, MSPA, MCR model, and Linkage Mapper Tools. Furthermore, we selected the most cost-effective EN by calculating six ENs’ connectivity-cost ratio (CCr index) and ranked the conservation priority for its sources and corridors. The results showed that the EN4 ranked highest in the CCr index and displayed a high conservation efficiency for all bird species. 93.41% of primary ES4 and 42.46% of secondary ES4 overlapped with the ecological conservation redline and the permanent basic farmland and could be well protected under current statutory planning. Our findings confirm that wading birds are the ideal focal species in EN planning for broader bird conservation in the context of the Yangtze River Delta. The constructed regional EN could contribute to establishing a linkage with the supra-regional EN and the world’s major bird migration flyway. Moreover, our cost-effective approach to bird conservation could provide new insights for targeting focal species from the perspective of habitat preference in multi-species EN planning.

Facilitation against herbivory more important than resource‐based niche differences for plant coexistence in a field experiment

Abstract Theory suggests that eutrophication impacts plant community biodiversity by constraining niche differences and increasing competitive inequalities among species, leading to the exclusion of weaker competitors. However, explicit tests of nutrient effects on the strength and direction of inter‐ and intraspecific plant–plant interactions that dictate coexistence are lacking, especially in complex field settings where multiple processes can simultaneously affect plant growth and reproduction. We conducted a field experiment in southeastern Vancouver Island, Canada, using four annual grassland plant species to test how species interactions responded to eutrophication and the covariation of herbivore pressure and neighbour species light‐ and moisture‐use. We found that focal species reproduction was limited by nutrient availability and herbivory, such that the nature of species interactions was context‐dependent. Competitive interactions failed to predict species persistence under these conditions. Instead, facilitation was critical—phytometers grown without neighbours consistently failed to produce seed under herbivore pressure meaning that fecundity significantly increased with neighbour density. Synthesis. Our work demonstrates the importance of species interactions in plant community responses to eutrophication but emphasizes that ‘indirect’ drivers of plant performance may influence or overwhelm nutrient effects on plant–plant competition. The widespread occurrence of mortality overcome primarily by facilitation highlights the importance of positive density dependence. Overall, our results suggest that knowledge of resource niche overlap may be insufficient to explain plant community responses to eutrophication. This highlights the necessity of considering the broader environmental context when leveraging ecological theory to understand global change effects in empirical settings.

Identification of closely related species in Aspergillus through Analysis of Whole-Genome.

The challenge of discriminating closely related species persists, notably within clinical diagnostic laboratories for invasive aspergillosis (IA)-related species and food contamination microorganisms with toxin-producing potential. We employed Analysis of the whole-GEnome (AGE) to address the challenges of closely related species within the genus Aspergillus and developed a rapid detection method. First, reliable whole genome data for 77 Aspergillus species were downloaded from the database, and through bioinformatic analysis, specific targets for each species were identified. Subsequently, sequencing was employed to validate these specific targets. Additionally, we developed an on-site detection method targeting a specific target using a genome editing system. Our results indicate that AGE has successfully achieved reliable identification of all IA-related species (Aspergillus fumigatus, Aspergillus niger, Aspergillus nidulans, Aspergillus flavus, and Aspergillus terreus) and three well-known species (A. flavus, Aspergillus parasiticus, and Aspergillus oryzae) within the Aspergillus section. Flavi and AGE have provided species-level-specific targets for 77 species within the genus Aspergillus. Based on these reference targets, the sequencing results targeting specific targets substantiate the efficacy of distinguishing the focal species from its closely related species. Notably, the amalgamation of room-temperature amplification and genome editing techniques demonstrates the capacity for rapid and accurate identification of genomic DNA samples at a concentration as low as 0.1 ng/μl within a concise 30-min timeframe. Importantly, this methodology circumvents the reliance on large specialized instrumentation by presenting a singular tube operational modality and allowing for visualized result assessment. These advancements aptly meet the exigencies of on-site detection requirements for the specified species, facilitating prompt diagnosis and food quality monitoring. Moreover, as an identification method based on species-specific genomic sequences, AGE shows promising potential as an effective tool for epidemiological research and species classification.

The weak genetic structure of Melolontha melolontha (L.) and Melolontha hippocastani (Fabr.), two important forest pests, indicates their large population sizes and effective gene flow

Abstract Cockchafers Melolontha spp. are polyphagous root pests and outbreak species of considerable economic importance to forestry in Europe. Knowledge of genetic diversity within and between cockchafer populations is largely unexplored but could lead to more effective monitoring and management strategies of these pests. In this study, we fill several gaps in the knowledge of the genetic population structure of Melolontha melolontha and Melolontha hippocastani. Using microsatellite loci and over 200 individuals per species, we examined the genetic structure of Melolontha spp. populations collected from three primary outbreak areas in central and southeastern Poland. We demonstrated that our focal species share some common genetic patterns, such as considerable genetic diversity within subpopulations (within sampling sites) with minor effects of past bottlenecks possibly masked by current population sizes. The estimates of effective population sizes, although subject to wide credibility intervals, indicated a large number of individuals contributing to further generations of the population. The migration rates exceed the threshold of one per generation required for gene flow and maintenance of population equilibrium, indicating limited impact from forest management practices on either cockchafer species. While genetic differentiation was observed in M. melolontha populations, supported by various indices (fixation index, principal coordinate analysis, assignment tests), the M. hippocastani populations were genetically similar. This disparity may hint at the potential historical divergence between these species. In this aspect, more detailed phylogeographic and population genetic studies covering a large area of the Palaearctic distributions of both species are required. Our findings constitute one of the initial efforts aimed at delineating the genetic diversity, differentiation, population structure, gene flow, and migration patterns within Melolontha spp. This exploration is especially significant for M. hippocastani, given its completely unexplored genetic population structure.

A Review of Two Decades of In Situ Conservation Powered by Public Aquaria

The European Union of Aquarium Curators (EUAC) boasts a membership of 150 dedicated individuals, standing as a vital cornerstone within the European public aquarium community. Since 2004, the EUAC Conservation Fund has granted over a quarter of a million euros to approximately 50 conservation projects spanning the globe. These initiatives, diverse in nature and scale, have yielded tangible impacts on local populations and their focal species. This paper delves into the outcomes of these conservation endeavors and proposes enhancements to ensure that the funding is unequivocally channeled towards conservation efforts. One resounding observation gleaned from the array of projects spotlighted in this study is the profound community engagement that emerges, irrespective of the final project outcomes. These endeavors serve as a catalyst for local communities, shedding light on subjects that would otherwise remain shrouded in obscurity. Furthermore, the EUAC-backed projects illuminate the expansive reach of public aquarium initiatives, transcending the confines of acrylic tank walls and institutional boundaries to resonate globally, heightening local awareness about the imperative to safeguard biodiversity. These findings underscore a prospective trajectory for both the EUAC and the public aquaria it comprises: an intensified advocacy and collaboration with legislative bodies to fortify in situ conservation measures. In essence, it is imperative that the public comprehends the pivotal role played by aquaria in preserving a multitude of species and acknowledges that their visits directly contribute to funding projects aimed at safeguarding species within their natural habitats.