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Background and Aims Not all plant–pollinator interactions are mutualistic, and in fact deceptive pollination systems are widespread in nature. The genus Arisaema has a pollination system known as lethal deceptive pollination, in which plants not only attract pollinating insects without providing any rewards, but also trap them until they die. Many Arisaema species are endangered from various disturbances, including reduction in forest habitat, modification of the forest understorey owing to increasing deer abundance, and plant theft for horticultural cultivation. We aimed to theoretically investigate how lethal deceptive pollination can be maintained from a demographic perspective and how plant and pollinator populations respond to different types of disturbance. Methods We developed and analysed a mathematical model to describe the population dynamics of a deceptive plant species and its victim pollinator. Calibrating the model based on empirical data, we assessed the conditions under which plants and pollinators could coexist, while manipulating relevant key parameters. Key Results The model exhibited qualitatively distinct behaviours depending on certain parameters. The plant becomes extinct when it has a low capability for vegetative reproduction and slow transition from male to female, and plant–insect co-extinction occurs especially when the plant is highly attractive to male insects. Increasing deer abundance has both positive and negative effects because of removal of other competitive plants and diminishing pollinators, respectively. Theft for horticultural cultivation can readily threaten plants whether male or female plants are frequently collected. The impact of forest habitat reduction may be limited compared with that of other disturbance types. Conclusions Our results have emphasized that the demographic vulnerability of lethal deceptive pollination systems would differ qualitatively from that of general mutualistic pollination systems. It is therefore important to consider the demographics of both victim pollinators and deceptive plants to estimate how endangered Arisaema populations respond to various disturbances. [ABSTRACT FROM AUTHOR]

The rise in species richness with area is one of the few ironclad ecological relationships. Yet, little is known about the spatial scaling of alternative dimensions of diversity. Here, we provide empirical evidence for a relationship between the richness of acoustic traits emanating from a landscape, or soundscape richness, and island area, which we term the SoundScape‐Area Relationship (SSAR). We show a positive relationship between the gamma soundscape richness and island area. This relationship breaks down at the smallest spatial scales, indicating a small‐island effect. Moreover, we demonstrate a positive spatial scaling of the plot‐scale alpha soundscape richness, but not the beta soundscape turnover, suggesting a direct effect of species on acoustic trait diversity. We conclude that the general scaling of biodiversity can be extended into the realm of ecoacoustics, implying soundscape metrics are sensitive to fundamental ecological patterns and useful in disentangling their complex mechanistic drivers. [ABSTRACT FROM AUTHOR]

Brook Trout (Salvelinus fontinalis) populations have experienced marked declines throughout their native range and are presently threatened due to isolation in small habitat fragments, land use changes, and climate change. The existence of numerous, spatially distinct populations poses substantial challenges for monitoring population status (e.g., abundance, recruitment, or occupancy). Genetic monitoring with estimates of effective number of breeders (Nb) provides a potentially powerful metric to complement existing population monitoring, assessment, and prioritization. We estimated Nb for 71 Brook Trout habitat units in mid‐Atlantic region of the United States and obtained a mean Nb of 73.2 (range 6.90–493). Our modeling approach tested whether Nb estimates were sensitive to differences in habitat size, presence of non‐native salmonids, base flow index, temperature, acidic precipitation, and indices of anthropogenic disturbance. We found significant support for three of our hypotheses including the positive influences of available habitat and base flow index and negative effect of temperature. Our results are consistent with presently observed and predicted future impacts of climate change on populations of this cold‐water fish. Importantly, these findings support the use of Nb in population assessments as an index of relative population status. [ABSTRACT FROM AUTHOR]

Simple Summary: After losing their habitat or having it broken up by infrastructure developments, one of the major threats to wild koalas is being hit by cars. Researchers analysed data for 345 koalas that were hit by cars on a 51 km section of the Peak Downs Highway in Queensland, Australia, from October 2014 to November 2023. We found that the spatial distribution of these accidents fit a random pattern along this stretch of road. Two factors seemed to predict where koalas might get hit: the amount of high-quality koala habitat nearby as defined by the local koalas' tree species preference, and driver visibility along the road. Because the landscape is relatively uniform in terms of landuse and vegetation, koalas can, and do, cross anywhere. More research, including detailed habitat mapping using geographic information systems and ground-truthing, is needed to help protect this important koala population and reduce the number of koala vehicle collisions and associated injury and mortality. After the loss and fragmentation of habitat, vehicle collisions are one of the main threats to the long-term survival of wild koalas. Koala road strike data were analysed for a section of the Peak Downs Highway between Nebo and Spencer's Gap, west of Mackay, Queensland, Australia. The analysis was carried out on 345 records (October 2014 to November 2023), and results suggested the spatial distribution of koala road strike followed a random pattern along this section of the highway, assuming a Poisson point pattern on a linear network. An analysis of the candidate predictors of koala vehicle collisions, including habitat and road variables, found that the amount of high-quality koala habitat (as defined by the local koalas' tree species preference) present and the driver visibility were the only significant predictors. The relative homogeneity of landuse and vegetation across this landscape may mean that koalas do not concentrate at specific crossing points. More research, including detailed habitat mapping, is needed into this population, which currently lacks government and conservation attention, to inform mitigation efforts and reduce mortality rates for this potentially nationally significant population. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are algorithms designed to infer the distribution of species using environmental and biotic variables and have become an important tool for ecologists and conservation biologists seeking to understand the implications of environmental change.Global datasets of environmental variables at resolutions of a few metres are increasingly available. SDMs fitted using such high‐resolution data allow researchers to investigate how local factors affect species occurrences at unprecedented fine spatial scales.As the spatial resolution of SDMs increases, we see a critical need to consider the characteristics of habitat types within or around raster pixels. In particular, we argue that the effects of habitat patches (EHPs, including habitat area, habitat configuration, and habitat diversity), measured focusing on patches or landscapes, have yet to be fully realized in SDMs.We provide guidelines to incorporate EHPs in SDMs. We explain why this development is important, describe approaches to properly conduct such analyses, and discuss pitfalls we foresee in testing EHPs.Synthesis. Ensuring that SDMs incorporating EHPs are properly designed will be key to increasing model predictive performance and to understanding which environmental factors influence the distribution of species at fine spatial scales. At a crucial time for nature conservation, we foresee that this will be a key step forward to understanding and protecting biodiversity. [ABSTRACT FROM AUTHOR]

Conservation of species requires the protection of the associated suitable habitat. However, it is usually not known how much habitat is required to detect a single rare species. This problem is important, and it is related directly to the success and optimization of conservation planning. However, to date, no statistical methods have been developed to address this problem adequately. In this study, from a statistical sampling theory, we propose an estimator to estimate the minimum area required to conserve one or more additional new rare species. The estimator is highly accurate, as demonstrated by numerical tests. Applying the estimator in a tropical forest plot showed that the additional habitat size required for discovering an additional individual of a previously unseen tropical tree species is about 3.86 ha with a SE of 1.10 ha. In conclusion, the proposed estimator may be applied to conservation planning by assisting conservation biologists and policymakers to balance urban‐related and conservation‐related land uses by estimating the minimum detection areas required for species. [ABSTRACT FROM AUTHOR]

Context: Anthropogenic habitat loss and fragmentation are major threats to ecosystems and a focus in conservation. However, conservation is often limited to considerations of site-level processes neglecting the effect of the surrounding landscape that might limit the effectiveness of restoration efforts. Objectives: Using seismic lines in Alberta’s oil sands as a case study, we demonstrate an approach that integrates spatial configuration of anthropogenic footprints to prioritize habitat defragmentation. Methods: We quantified the effects of seismic line density and configuration on functional footprints for caribou, butterfly diversity, and vascular plant diversity, to predict whether edge effects are more pronounced under different line densities and configurations. We then estimated the portion of the original functional footprint that would persist in the landscape due to the co-occurrence with other anthropogenic activities. Results: We found that functional footprint for caribou grows rapidly as habitat loss increases. In contrast, butterflies and plants exhibited a more gradual and linear growth in functional footprints at more local scales. This effect varies based on configuration of lines, either suppressing or facilitating the effect of habitat loss on functional habitats. Finally, restoration of all seismic lines without considering other footprints would reduce the original functional footprint by only 57% for caribou. Conclusions: Restoration efforts for habitat defragmentation rarely consider the spatial configuration of linear features, particularly as it relates to the co-occurrence of other footprints that are not being restored. Our functional approach to defragmentation of habitat encompasses different spatial concepts related to anthropogenic forest fragmentation and allows up to a 25-fold gain in cost-effectiveness for seismic lines restoration. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of spatio-temporal dynamics of urban sprawl on habitats in Istanbul, using the CORINE 1990 and 2018 land cover datasets. In this context, by means of geographic information system (GIS) tools and techniques, land cover maps are created for land cover change analysis and visualization, the Shannon's entropy method is performed for measuring urban growth and sprawl, and the landscape metrics method is applied for assessing habitat loss and fragmentation. Results indicate that the rate of urban sprawl in the area increased by 0.1230 as per the Shannon's entropy index over the 28-year period. Similarly, the Shannon Diversity Index and the Shannon Evenness Index rose from 1.74 to 1.85 and from 0.68 to 0.70, respectively, indicating an increase in urbanization within the area. Moreover, an analysis of patch numbers reveals that habitat fragmentation increased in shrub and/or herbaceous vegetation associations (72.55%), heterogeneous agricultural areas (45.11%), arable lands (42.5%), forests (36.13%) and pastures (15.05%), due to urbanization. Habitat fragmentation has had a detrimental effect on the local biodiversity. While 15 flora species were identified as vulnerable, 13 as endangered and 9 as critically endangered, 19 fauna species were identified as vulnerable and 5 as endangered. This study highlights that the natural habitats and biodiversity of Istanbul will suffer further decline due to urbanization unless sustainable urban planning and management policies are put into practice. It is essential to have controlled urban development to preserve the ecosystem's carrying capacity, and urbanization decisions must consider this requirement. [ABSTRACT FROM AUTHOR]

Mangroves are one coastal ecosystem that has experienced a long history of fragmentation and loss by urbanization. Yet, these small mangroves in urban areas are often missing from current wetland inventory due to lower resolution mapping methods and size classifications that may overlook these mangroves in highly urbanized areas. We mapped mangroves along a gradient of urbanization in Miami-Dade County, Florida (MDC) by combining several landcover databases, high-resolution imagery, and ground-truthing. We compared our newly mapped mangrove dataset with the Florida Fish and Wildlife Conservation Commission’s (FWC) current mangrove habitat dataset. We quantified differences in mangrove area, fragmentation metrics, and shape complexity across three urban intensities within MDC and between the datasets. We identified an additional 386 mangrove patches that were missed by the FWC map. The majority of these newly found mangroves were in the most urban regions of MDC. We identified average mangrove stand size in the least urbanized region is about 29 times bigger than those found in the most urbanized region. We also found that the FWC dataset significantly overestimated average mangrove stand size (18.32-ha) compared to the newly mapped mangrove dataset (1.43-ha) in the most urbanized region. Our results demonstrate that large scale wetland mapping efforts, like those of state agencies, provide valuable mangrove area estimations but may miss key fragmentation patterns by not including smaller mangrove stands scattered throughout highly urbanized regions. Habitat maps that capture these smaller, fragmented mangroves are needed to evaluate how urbanization shapes mangrove extent and ecosystem function. [ABSTRACT FROM AUTHOR]

Disentangling the roles of structural landscape factors and animal movement behaviour can present challenges for practitioners managing landscapes to maintain functional connectivity and achieve conservation goals. We used a landscape genetics approach to combine robust demographic, behavioural and genetic datasets with spatially explicit simulations to evaluate the effects of anthropogenic barriers (dams, culverts) and natural landscape resistance (gradient, elevation) affecting dispersal behaviour, genetic connectivity and genetic structure in a resident population of Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi). Analyses based on 10 years of sampling effort revealed a pattern of restricted dispersal, and population genetics identified discrete population clusters between distal tributaries and the mainstem stream and no structure within the mainstem stream. Demogenetic simulations demonstrated that, for this population, the effects of existing anthropogenic barriers on population structure are redundant with effects of restricted dispersal associated with the underlying environmental resistance. Our approach provides an example of how extensive field sampling combined with landscape genetics can be incorporated into spatially explicit simulation modelling to explore how, together, movement ecology and landscape resistance can be used to inform decisions around restoration and connectivity. [ABSTRACT FROM AUTHOR]

Biodiversity conservation in human‐inhabited landscapes is increasingly gaining attention due to the global decline of species. Understanding the impact of human activities on avian functional ecology is becoming increasingly important as habitats are transformed. We assessed the influence of habitat fragmentation on avian functional diversity (FD), focusing on metrics like functional richness (FRic), evenness (FEve) and divergence (FDiv). We calculated the FRic, FEve and FDiv across habitats using 'fundiversity' R package. We also calculated the Enhanced Vegetation Index (EVI) and estimated land‐use cover of the study area from Landsat 8 images. We observed higher FD in minimally disturbed habitats, where among the habitats, woodland had high FD while human settlement had low. This supports the intermediate disturbance hypothesis, which suggests that moderate disturbance can increase species diversity. Our findings emphasise the pivotal role of fragmented habitats in shaping avian functional ecology, with environmental variables such as the EVI influencing diversity across habitats. Hence, we promote sustainable conservation connectivity, proper land management practices and conservation‐friendly agricultural practices for sustainable biodiversity conservation. [ABSTRACT FROM AUTHOR]

The unprecedented habitat fragmentation or loss has threatened the existence of many species. Therefore, it is essential to understand whether and how these species can pace with the environmental changes. Recent advantages in landscape genomics enabled us to identify molecular signatures of adaptation and predict how populations will respond to changing environments, providing new insights into the conservation of species. Here, we investigated the pattern of neutral and putative adaptive genetic variation and its response to changing environments in a tertiary relict tree species, Taxus cuspidata Sieb. et Zucc, which is distributed in northeast China and adjacent regions. We investigated the pattern of genetic diversity and differentiation using restriction site‐associated DNA sequencing (RAD‐seq) and seven nuclear microsatellites (nSSRs) datasets. We further explored the endangered mechanism, predicted its vulnerability in the future, and provided guidelines for the conservation and management of this species. RAD‐seq identified 16,087 single nucleotide polymorphisms (SNPs) in natural populations. Both the SNPs and nSSRs datasets showed high levels of genetic diversity and low genetic differentiation in T. cuspidata. Outlier detection by FST outlier analysis and genotype‐environment associations (GEAs) revealed 598 outlier SNPs as putative adaptive SNPs. Linear redundancy analysis (RDA) and nonlinear gradient forest (GF) showed that the contribution of climate to genetic variation was greater than that of geography, and precipitation played an important role in putative adaptive genetic variation. Furthermore, the genetic offset and risk of non‐adaptedness (RONA) suggested that the species at the northeast edge may be more vulnerable in the future. These results suggest that although the species has maintained high current genetic diversity in the face of recent habitat loss and fragmentation, future climate change is likely to threaten the survival of the species. Temperature (Bio03) and precipitation (Prec05) variables can be potentially used as predictors of response of T. cuspidata under future climate. Together, this study provides a theoretical framework for conservation and management strategies for wildlife species in the context of future climate change. [ABSTRACT FROM AUTHOR]

This research delves into the effects of weir‐induced habitat fragmentation on the diversity and structure of benthic macroinvertebrate communities in Topyeong Stream in the Republic of Korea. Through comprehensive zonation, environmental assessments and analyses of macroinvertebrate populations, the study brings to light the significant impact of physical barriers within aquatic ecosystems. Findings reveal notable differences in macroinvertebrate diversity among various stream zones, with alpha diversity measurements demonstrating the significant influence of habitat conditions on biodiversity. Beta diversity analyses uncovered considerable species turnover, pointing to distinct ecological features within fragmented habitats. Mantel tests solidified a significant link between geographical separation and species composition, highlighting the critical impact of spatial isolation arising from habitat fragmentation. The research also pinpointed environmental factors, including habitat size and depth variation, as critical influences on macroinvertebrate community dynamics. Discussions on conservation tactics centered on habitat restoration and forward‐thinking water management strategies aim to counteract the negative consequences of fragmentation and drought. This study emphasizes the essential need for cohesive conservation initiatives to preserve aquatic biodiversity and the functionality of ecosystems amidst human‐induced challenges. [ABSTRACT FROM AUTHOR]

Understanding the relationship between multi-scale processes driving community- and population-level diversity can guide conservation efforts. While the importance of population-level genetic diversity is widely recognized, it is not always assessed for conservation planning, and positive correlations with community-level diversity are sometimes assumed, such that only the latter is measured. We surveyed species richness and cumulative multispecies abundance of crayfishes in impounded and unimpounded streams in the southern Appalachian Mountains (Alabama, USA). We simultaneously assessed levels of population genetic diversity within two focal crayfishes (Faxonius validus and F. erichsonianus) using nuclear (nDNA; inter-simple sequence repeat (ISSR)) and mitochondrial DNA (mtDNA; mitochondrial DNA cytochrome oxidase subunit I (mtCOI)) markers. We then tested for species-genetic diversity correlations (SGDCs), species diversity-abundance correlations (i.e., more individuals hypothesis, MIH), and abundance-genetic diversity correlations (AGDCs) across sites. We also examined the relationship between each of the three different types of correlation (i.e., species richness, cumulative multispecies abundance, and population genetic diversity) and stream habitat characteristics and fragmentation. Surprisingly, based on F. validus mtDNA data, sites with the greatest multispecies abundance had the lowest genetic diversity, indicating a negative AGDC. However, no AGDC was evident from nDNA. There was no evidence of SGDCs for F. validus based on either of the two genetic data types. For F. erichsonianus, there was no evidence for SGDC or AGDC. When considering the community-level data only, there was no support for the MIH. Stream width was positively correlated with F. validus genetic diversity, but negatively correlated with multispecies abundance. Similarly, species richness was positively correlated with stream width in unimpounded streams but negatively correlated with width in impounded streams. These findings indicate that community-level diversity cannot be indiscriminately used as a proxy for population-level diversity without empirically testing this correlation on the focal group. As such, community- and population-level assessments for multiple crayfish species are needed to better understand drivers of diversity and eco-evolutionary processes which will aid in the conservation of this vulnerable taxonomic group. [ABSTRACT FROM AUTHOR]

Context: Abiotic filtering, including environmental and dispersal filtering, is frequently observed resulting in reduced diversity and more similar species assemblages following habitat fragmentation. Nonetheless, the significance of competitive exclusion is often underestimated. Objectives: We investigated the dominant assembly process among termite communities on land-bridge islands, focusing on species known for their high territoriality. We hypothesized that competitively superior species tend to dominate more favorable habitats, such as larger and less isolated islands. Consequently, we anticipated lower diversity and greater similarity in species assemblages than would be expected. Methods: Termite communities were surveyed using standardized transects on 24 islands. We quantified the standardized effects of island area and isolation on taxonomic, phylogenetic and functional diversity by comparing observed patterns with randomly generated communities (i.e., stochastic process). A phylogenetic generalized linear mixed model (PGLMM) was conducted to examine species-specific responses to environmental factors and competition intensity (i.e., heterospecific abundance). Results: We found that taxonomic, phylogenetic and functional diversity were lower than expected on larger and less isolated islands, suggesting that competitive exclusion was the dominant mechanism shaping termite communities in TIL. PGLMM showed that two fungus-growing species with larger body sizes increased with competition intensity, while other species exhibited negative responses. Notably, the abundance of fungus-growing species showed sharper increase with island area and decrease with isolation compared to other feeding groups. These findings demonstrate that competitively superior species prefer high-quality habitats and are more sensitive to habitat fragmentation. Conclusions: Our study highlights the significance of competitive exclusion in shaping termite communities and emphasizes the need to consider both competitive and niche difference among species or functional groups when predict changes in community structure and biodiversity loss resulting from habitat fragmentation. [ABSTRACT FROM AUTHOR]

Identification of highly biodiverse areas has become a crucial step in protecting species richness, especially considering the rapid collapse of biodiversity and the limited funds available to avert, far less to reverse, these trends. Therefore, we aimed to identify the most important areas for the conservation of specified mammalian groups in Southern Asia, a region rich in biodiversity hotspots threatened by increasing rates of habitat loss and other anthropogenic activities. To achieve this, we modelled the occupancy of ungulates and of small, medium and large carnivorans at 20 study sites across the region and identified hotspots of species richness. We analysed the variation of estimated space use between different species groups and ranked areas according to their predicted importance for mammalian species conservation. Our results reveal a significant positive correlation in the spatial utilization patterns of competitive carnivores, yet no correlation among carnivores and their prey species, suggesting that anthropogenic impacts in the region are constraining species to coexist in only the few remaining suitable areas, superseding interactions between species guilds. Although the rank of site importance varied amongst species groups, we were able to identify a consensus on sites that are crucial for the conservation of all groups considered. Most of these top-ranking sites were located in the peninsular region of Thailand. We argue that, of the areas assessed, these sites represent the most important refuges for species conservation in the region, and their protection is critical for the maintenance of the biodiversity in Southern Asia. [ABSTRACT FROM AUTHOR]

Tropical dry forests are the most threatened of all the major tropical forest types and less than 25% of TDF currently remain worldwide. They are located mostly in South America. Parameters such as habitat loss, fragmentation and loss of connectivity have been identified as the main threats to biodiversity. This research aims to discover the forests changes, the evolution of connectivity and fragmentation of the South American tropical dry forest between 1992 and 2020. Land uses layers provided by the Copernicus program were employed, and land uses change, fragmentation and structural connectivity were analyzed in GIS systems. To calculate the functional connectivity, the Graphab software was used. The results showed a loss of forest surface, where fragmentation increased and a loss of functional connectivity between 25% and 49% occurs depended on the parameter analysed. On the other hand, some areas were recovered. Brazil is the country that recovered the most forest area and Argentina, Paraguay and Bolivia those that lost the most area. Only 31% of the area was not altered between 1992 and 2020. Human activities such as deforestation, agriculture expansion, and urbanization have led these forests to become increasingly fragmented and worse connected impacting on both ecological and socio-economic aspects. Supranational measures must be taken to mitigate the negative impacts of fragmentation and the loss of connectivity. [ABSTRACT FROM AUTHOR]

This study comprehensively analyses spatiotemporal land use/land cover (LULC) dynamics within a 10-km buffer zone surrounding Volcanoes National Park (VNP), Rwanda, from 2000 to 2019, integrating biophysical and socio-economic drivers. It aims to quantify LULC change extent, rate, and type around VNP and inside the park; identify socio-economic, demographic, and policy drivers of LULC change; and evaluate the impact of LULC changes on VNP's biodiversity via habitat fragmentation, connectivity, and species diversity. Employing remote sensing, spatial modelling, and field data, we reveal profound transformations within the park's periphery. Forests and woodlots have significantly declined, replaced by agriculture, grasslands, and built-up areas, particularly in the 5.1–10 km belt (92.29% forest loss). While reforestation efforts exist, they are outpaced by deforestation, creating a stark deforestation-to-reforestation ratio of 12:1 in the 5.1 10 km belt and 6:1 in the 0–5 km belt. This alarming trend threatens VNP's biodiversity as resource dependent communities continue to extract firewood, construction materials, and beanpoles from the park. To mitigate these impacts, we propose integrated strategies encompassing strengthened law enforcement, sustainable land management practices, community-based conservation initiatives, and alternative livelihood development. [ABSTRACT FROM AUTHOR]

Construction and paving of road infrastructures is on the rise globally. Roads have many negative impacts on the environment, including changes and damages to landscape connectivity, fragmentation and disrupting of ecological corridors, loss of habitats, air pollution, noise pollution and light pollution. Here we aimed to examine the impacts of the construction of a major road (national Highway 6 in Israel, 188 km long) on landscape fragmentation. To this end we mapped the land cover at three-time steps: 1997 (before the construction of the road began), 2009 and 2019, quantifying both patch-based metrics (using Frgastats), the continuous metrics of landscape connectivity (using Circuitscape) and landscape continuity, adapting a before-after-control-impact methodology. Analyzing changes in those metrics for sections of the road based on their time of construction and on the distance from the highway, we found that most changes took place within a distance of up to 1 km from the new highway, starting after road construction began. We also found that the patch-based metrics and the continuous metrics were weakly correlated. We conclude that each of those different approaches has its merits and limitations, that they are complementary and that jointly they provide us with better understanding of landscape changes. [ABSTRACT FROM AUTHOR]

Dispersal of propagules (seeds, spores) from a geographically isolated habitat into an uninhabitable matrix can play a decisive role in driving population dynamics. ODE and integrodifference models of these dynamics commonly feature a “dispersal success” parameter representing the average proportion of dispersing propagules that remain in viable habitat. While dispersal success can be estimated by empirical measurements or by integration of dispersal kernels, one may lack resources for fieldwork or details on dispersal kernels for numerical computation. Here we derive simple upper bounds on the proportion of propagule loss—the complement of dispersal success—that require only habitat area, habitat perimeter, and the mean dispersal distance of a propagule. Using vector calculus in a probabilistic framework, we rigorously prove bounds for the cases of both symmetric and asymmetric dispersal. We compare the bounds to simulations of integral models for the population of Asclepias syriaca (common milkweed) at McKnight Prairie—a 14 hectare reserve surrounded by agricultural fields in Goodhue County, Minnesota—and identify conditions under which the bounds closely estimate propagule loss. [ABSTRACT FROM AUTHOR]

The fragmentation of natural environments, generally a consequence of human activity, is one of the main threats to biodiversity. The conservation or creation of ecological corridors is essential in an attempt to remedy this fragmentation. We propose a multi-species model to help decision-makers select an optimal network of corridors from a very general potential network, within a budgetary constraint. The selected network must link a given set of biodiversity reservoirs both spatially and biologically. It must therefore be adapted to a given set of species, i.e. it must take account of the fact that certain corridors and reservoirs are more or less suitable for certain species. The quality of the selected network is measured against the quality of the potential network. This network must also take into account the distance certain species have to travel to connect reservoirs, as well as the possibility for certain species to connect reservoirs even when certain corridors have become impassable, thanks to redundant paths. The proposed model is formulated by a mixed-integer mathematical program. A small example illustrates the model and its resolution in detail. Experiments on larger examples using one of the efficient commercial solvers currently available demonstrate the model's practicability. [ABSTRACT FROM AUTHOR]

Urbanization and fragmentation of habitat are major drivers of population declines in wildlife in cities. This study evaluated fragmentation of aquatic systems in the context of urbanization, using the Eastern long-necked turtle Chelodina longicollis as a model as it is a generalist species, highly vagile and engages in regular overland migration. During two seasons (2020-22), we compared C. longicollis demography in stormwater ponds in two distinct urban drainages, one with greater habitat connectivity (lower road network and an unmodified creek) and one with lower habitat connectivity (higher road network and stormwater drains) in Canberra, south-eastern Australia. Most of the parameters related to habitat (pond age and size) and food requirements (phosphate and prey biomass) for C. longicollis were similar between the two drainages, in addition to proportion of females, overall size-frequency distributions and population size (corrected for variation in capture probability). However, there was a significant effect of the interaction between pond habitat connectivity and pond size with population sizes increasing more steeply in higher than in lower connectivity sites (F1, 4 = 14.3, p = 0.02). We also recaptured a marked turtle from a previous study in the drainage with more habitat connectivity, 14 years later and 15 km from its initial point of capture. This demonstrates the ability of the species to move within an urbanized context. Despite evidence of C. longicollis being resilient to urbanization, dispersal constraints seem to affect population dynamics and long term population viability in areas with low habitat connectivity. [ABSTRACT FROM AUTHOR]

Abstract Understanding the determinants of biodiversity in fragmented habitats is fundamental for informing sustainable landscape development, especially in urban landscapes that substantially fragment natural habitat. However, the relative roles of landscape and habitat characteristics, as emphasized by two competing frameworks (the island biogeography theory and the habitat diversity hypothesis), in structuring species assemblages in fragmented habitats have not been fully explored. This study investigated bird assemblages at 26 habitat patches (ranging in size from 0.3 to 290.4 ha) in an urban landscape, southwest China, among which habitat type composition and woody plant species composition varied significantly. Through 14 bird surveys conducted over six breeding seasons from 2017 to 2022, we recorded 70 breeding bird species (excluding birds recorded only once and fly-overs, such as raptors, swallows and swifts), with an average of 26 ± 10 (SD) species per patch. We found that patch area had significant direct and indirect effects on bird richness, with the indirect effects mediated by habitat richness (i.e., the number of habitat types). Isolation (measured as the distance to the nearest patch), perimeter to area ratio (PAR), and woody plant richness did not significantly predict variation in bird richness. Furthermore, none of these factors significantly sorted bird species based on their functional traits. However, the overall makeup of bird assemblages was significantly associated with the specific habitat types and woody plant species present in the patches. The results suggest that neither the island biogeography theory nor the habitat diversity hypothesis can fully explain the impacts of habitat fragmentation on bird richness in our study system, with their roles primarily being linked to patch area. The findings that habitat and plant compositions were the major drivers of variation in bird assemblage composition offer valuable insights into urban planning and green initiatives. Conservation efforts should focus not only on preserving large areas, but also on preventing urban monocultures by promoting diverse habitats within those areas, contributing to the persistence of meta-communities.

This study describes the characteristics of forest fragments occupied by a Critically Endangered endemic Peruvian primate, the San Martín titi monkey, Plecturocebus oenanthe (Pitheciidae; Platyrrhini). We selected 45 fragments; 20 had already been surveyed in 2015 by the Proyecto Mono Tocón (six of these had been further split, resulting in 27 fragments); an additional 18 fragments were randomly selected from satellite images. We surveyed these fragments for the presence of P. oenanthe and determined characteristics of the fragments (size, shape, tree density, canopy height) and of the landscape (distance to nearest fragment and road). We also examined changes in the number of fragments and in forest cover between 2015 and 2019. We encountered P. oenanthe in all surveyed fragments except for the smallest one (0.2 ha). Our findings suggest that P. oenanthe can persist in fragments with a wide range of characteristics, particularly with regard to size and tree density. Unless fragmentation continues and overall forest cover in the area diminishes further, the species may be able to persist even in a fragmented landscape, provided that the matrix allows for movements between fragments. However, persistence might not be long-term if groups are not reproductive, populations become too small, and reduced gene flow results in inbreeding. [ABSTRACT FROM AUTHOR]

Microorganisms are important members of seagrass bed ecosystems and play a crucial role in maintaining the health of seagrasses and the ecological functions of the ecosystem. In this study, we systematically quantified the assembly processes of microbial communities in fragmented seagrass beds and examined their correlation with environmental factors. Concurrently, we explored the relative contributions of species replacement and richness differences to the taxonomic and functional β-diversity of microbial communities, investigated the potential interrelation between these components, and assessed the explanatory power of environmental factors. The results suggest that stochastic processes dominate community assembly. Taxonomic β-diversity differences are governed by species replacement, while for functional β-diversity, the contribution of richness differences slightly outweighs that of replacement processes. A weak but significant correlation (p < 0.05) exists between the two components of bdiversity in taxonomy and functionality, with almost no observed significant correlation with environmental factors. This implies significant differences in taxonomy, but functional convergence and redundancy within microbial communities. Environmental factors are insufficient to explain the β-diversity differences. In conclusion, the assembly of microbial communities in fragmented seagrass beds is governed by stochastic processes. The patterns of taxonomic and functional β-diversity provide new insights and evidence for a better understanding of these stochastic assembly rules. This has important implications for the conservation and management of fragmented seagrass beds. [ABSTRACT FROM AUTHOR]

Macrophytes often live in fluvial backwaters that have a variety of hydrological connections to a main river. Since the ability of these plants to adapt to changing environments may depend on the genetic diversity of the populations, it is important to know whether it can be influenced by habitat characteristics. We examined the microsatellite polymorphism of the submerged macrophyte Ceratophyllum demersum from various backwaters and showed that the genetic diversity of this plant clearly reflects habitat hydrological differences. The greatest genetic variability was found in a canal system where constant water flow maintained a direct connection between the habitats and the river. In contrast, an isolated backwater on the protected side of the river had the lowest plant genetic diversity. Oxbows permanently connected to the branch system with static or flowing water, and former river branches temporarily connected to the main bed contained populations with moderately high or low genetic variability. The results demonstrate that habitat fragmentation can be a result not only of the loss of direct water contact, but also of the lack of flowing water. Adverse hydrological changes can reduce the genetic diversity of populations and thus the ability of this macrophyte to adapt to changing environments. [ABSTRACT FROM AUTHOR]

This study examines the population structure, ecological niche, and vulnerability to climate change of the woolly dormouse Dryomys laniger in Türkiye. Integrating genetic data with species distribution modeling, the research predicts suitable habitats for D. laniger under current and future climate change scenarios until the year 2100. Using an ensemble of two machine learning models, this study finds that by 2040, the range of D. laniger will be reduced significantly, particularly in southern populations. Eastern areas emerge as a potential refuge, showing slight expansion and colonization. The low genetic diversity in this eastern population indicates the need for long-term adaptability of D. laniger. Due to the unique adaptive potential of each population, this research highlights the importance of region-specific management plans to ensure the long-term survival of this species, which appears to be vulnerable to habitat fragmentation. [ABSTRACT FROM AUTHOR]

Aim: Plant herbivory and disease, which are often associated with each other but subject to different processes, are pivotal in biodiversity maintenance and ecosystem function. Although drivers of plant herbivory and disease have been widely studied separately, their relationships, patterns and determinants remain unclear in fragmented landscapes. Methods: We surveyed incidence and severity of foliar herbivory and disease of 2,027 adult trees within 30 sites in 17 tropical forest fragments in Xishuangbanna, southwestern China. We aim to explore the relationship of plant herbivory and disease, and effects of local environmental variables (forest type, plant richness, elevation, slope, soil properties) and landscape environmental variables (patch size, edge distance, isolation). Results: We found that incidence, but not severity of disease was positively correlated with that of herbivory. Herbivory severity and incidence were more associated with local variables; both increased with plant richness but decreased with soil nutrients and pH. In contrast, the landscape variable isolation was the dominant driver of disease, with lower severity and incidence in contiguous forests than forest fragments. Conclusion: In summary, we show that herbivory and disease are associated with drivers at different scales in fragmented landscapes. Herbivory is mainly driven by local-scale variables, while disease is mainly driven by landscape-scale variables. To control plant herbivory and disease in fragmented landscapes, increasing landscape connectivity and conserving different forest types are urgently required to maintain ecosystem functions under global land use change. [ABSTRACT FROM AUTHOR]

Anthropogenic habitat loss is widely recognized as a primary environmental concern. By contrast, debates on the effects of habitat fragmentation persist. To facilitate overcoming these debates, here we: (i) review the state of the literature on habitat fragmentation, finding widespread confusion and stigma; (ii) identify consequences of this for biodiversity conservation and ecosystem management; and (iii) suggest ways in which research can move forward to resolve these problems. Confusion is evident from the 25 most‐cited fragmentation articles published between 2017 and 2021. These articles use five distinct concepts of habitat fragmentation, only one of which clearly distinguishes habitat fragmentation from habitat area and other factors ('fragmentation per se'). Stigmatization is evident from our new findings that fragmentation papers are more charged with negative sentiments when compared to papers from other subfields in the environmental sciences, and that fragmentation papers with more negative sentiments are cited more. While most empirical studies of habitat fragmentation per se find neutral or positive effects on species and biodiversity outcomes, which implies that small habitat patches have a high cumulative value, confusion and stigma in reporting and discussing such results have led to suboptimal habitat protection policy. For example, government agencies, conservation organizations, and land trusts impose minimum habitat patch sizes on habitat protection. Given the high cumulative value of small patches, such policies mean that many opportunities for conservation are being missed. Our review highlights the importance of reducing confusion and stigma in habitat fragmentation research. To this end, we propose implementing study designs in which multiple sample landscapes are selected across independent gradients of habitat amount and fragmentation, measured as patch density. We show that such designs are possible for forest habitat across Earth's biomes. As such study designs are adopted, and as language becomes more precise, we expect that confusion and stigma in habitat fragmentation research will dissipate. We also expect important breakthroughs in understanding the situations where effects of habitat fragmentation per se are neutral, positive, or negative, and the reasons for these differences. Ultimately this will improve efficacy of area‐based conservation policies, to the benefit of biodiversity and people. [ABSTRACT FROM AUTHOR]

Context: Human disturbance has transformed ecosystems globally, yet studies of the ecological impact of landscape modification are often confounded. Non-random patterns of land clearing cause differing vegetation types and soil productivity between fragments in modified landscapes and reference areas—like national parks—with which they are compared. Objectives: We sought to explore the influence of land modification on herpetofauna and small mammal communities using multiple biodiversity measures—species richness and diversity, individual species abundance, and community composition. We also aimed to investigate the role of traits such as diet, habitat breadth, and litter size in moderating species responses to land modification. Methods: We established 100 sampling sites to survey herpetofauna and small mammals in 11 fragments in an agricultural landscape compared to 11 ecologically equivalent ‘pseudo-fragments’ in a nearby national park in south-eastern Australia. We selected pairs of fragments and pseudo-fragments of the same size and vegetation type, and used identical survey methods to sample pairs simultaneously, thereby controlling for numerous confounding factors, such as differing vegetation type, weather, and survey effort. Results: Species richness and diversity were similar between fragments and pseudo-fragments. Despite this, we found community composition differed markedly—driven by the varying responses of individual species—indicating a shift in fauna communities associated with land modification. Fossorial habit, omnivorous diet, and broad habitat requirements led to higher abundance in fragments whilst arboreality, carnivorous diet, and narrow habitat requirements led to higher abundance in pseudo-fragments. Conclusions: Although fragments hold similar numbers of species to continuous areas, they contain distinct and novel communities, and sustain high abundances of some species. These diverse communities are dominated by native species, including threatened species, and their distinctive composition is shaped by traits conducive to persistence amidst land modification. These novel communities may provide a reservoir of resilience in the face of environmental change and should be viewed as complementary to conservation areas. [ABSTRACT FROM AUTHOR]

Habitat fragmentation and host community composition are implicated as key drivers of changing tick populations and tick‐borne pathogen dynamics, altering infection risk through coupled socioecological pathways that mediate interactions between tick vectors, vertebrate hosts, and humans. Patterns of host diversity may be particularly idiosyncratic across urbanized landscapes, due to trade‐offs between extreme fragmentation that reduces habitat suitability and access, and human activities that artificially increase resource availability for wildlife. We used camera and hair trap surveys and tick sampling to identify links between landscape composition and configuration, the mammalian host community, and the presence of three tick vector species at a human–wildlife interface in New York City, an emerging area within an endemic region for several tick‐borne diseases. We found that human infrastructures, such as the presence of fences in yards, could affect mammal host community composition by changing the "hardness" of edges between urban greenspaces and residential areas. We identified yard‐ and broader landscape‐level features associated with the presence of urban mammal species, and identified cascading effects of host community composition on tick distribution in yards, suggesting management implications for the mitigation of human exposure to tick‐borne pathogens. In particular, we identified a possible role of ubiquitous mesomammals, such as raccoons (Procyon lotor), in transporting Amblyomma americanum ticks between parks and neighboring residential yards, and confirmed the key role of white‐tailed deer (Odocoileus virginianus) for introducing Ixodes scapularis ticks into yards. Our results challenge assumptions that biodiversity loss in human‐modified areas always increases the risk for tick‐borne diseases. Instead, we found many residential sites had higher mammal species richness and higher detection of low reservoir competent ("dilution") hosts for Borrelia burgdorferi, such as opossums (Didelphis virginiana), than paired forested greenspaces. Our study highlights the importance of disentangling the mechanisms mediating tick‐borne disease hazard as a critical first step toward reducing urban tick‐borne disease risk. [ABSTRACT FROM AUTHOR]

The grasslands and shrub areas of the Patagonian steppe are the most frequent habitat for the “Near Threatened” armadillo, known as pichi (Zaedyus pichiy). Dense exotic conifer plantations are replacing the steppe in Argentinean northern Patagonia. This study aimed to evaluate the effect of conifer afforestation on the occurrence and food availability in a Z. pichiy population in north-western Patagonia. Fifteen sites in the native steppe and 50 in exotic pine plantations were sampled. We recorded the number of signs of pichi’s presence and the diversity of invertebrates. Signs of Z. pichiy presence decreased in pine afforestation compared to the native steppe. Additionally, we found a decrease in the abundance, richness, diversity, and biomass of arthropods in pine plantations. Therefore, the presence of pine plantations in the steppe reduces the main food items of Z. pichiy and also eliminates the native steppe vegetation structure that provides preferred places to dig burrows. Pine monocultures do not provide a suitable habitat for Z. pichiy and may exacerbate the degradation of an already disturbed environment. [ABSTRACT FROM AUTHOR]

Ecologists have historically quantified fundamental biodiversity patterns, including species‐area relationships (SARs) and beta diversity, using observed species counts. However, imperfect detection may often bias derived community metrics and subsequent community models. Although several statistical methods claim to correct for imperfect detection, their performance in species‐area and β‐diversity research remains unproven. We examine inaccuracies in the estimation of SARs and β‐diversity parameters that emerge from imperfect detection, and whether such errors can be mitigated using a non‐parametric diversity estimator (iNEXT.3D) and Multi‐Species Occupancy Models (MSOMs). We simulated 28,350 sampling regimes of 2835 fragmented communities, varying the mean and standard deviation of species detection probabilities, and the number of sampling repetitions. We then quantified the bias, accuracy, and precision of derived estimates of model coefficients for SARs and the effects of patch area on β‐diversity (pairwise Sørensen similarity). Imperfect detection biased estimates of all evaluated parameters, particularly when mean detection probabilities were low, and there were few sampling repetitions. Observed counts consistently underestimated species richness and SAR z‐values, and overestimated SAR c‐values; iNEXT.3D and MSOMs only partially resolved these biases. iNEXT.3D provided the best estimates of SAR z‐values, although MSOM estimates were generally comparable. All three methods accurately estimated pairwise Sørensen similarity in most circumstances, but only MSOMs provided unbiased estimates of the coefficients of models examining covariate effects on β‐diversity. Even when using iNEXT.3D or MSOMs, imperfect detection consistently caused biases in SAR coefficient estimates, calling into question the robustness of previous SAR studies. Furthermore, the inability of observed counts and iNEXT.3D to estimate β‐diversity model coefficients resulted from a systematic, area‐related bias in Sørensen similarity estimates. Importantly, MSOMs corrected for these biases in β‐diversity assessments, even in suboptimal scenarios. Nonetheless, as estimator performance consistently improved with increasing sampling repetitions, the importance of appropriate sampling effort cannot be understated. [ABSTRACT FROM AUTHOR]

Information about wildlife diets is crucial for comprehending how species adapt to varying environments in fragmented habitats and for developing effective conservation strategies. White‐headed langurs (Trachypithecus leucocephalus) are exclusively found in fragmented limestone forests in southwestern China. To investigate the effects of habitat fragmentation on langurs' diets, we collected published dietary data and relevant environmental factors spanning from 1996 to 2021 at two regions with different degrees of fragmentation (Banli > Bapen), from 10 studies (three of Banli and seven of Bapen). The results demonstrated that the diets of white‐headed langurs were significantly influenced by environmental factors, including habitat fragmentation, annual rainfall, and mean annual temperature. Food item diversity index was significantly and positively affected by the fragmentation index, the higher fragmentation the langurs suffered, the more diverse food items they consumed. Besides, fruit consumption was negatively influenced by annual rainfall and the consumption of other items was influenced by mean annual temperature. Notably, although there are no significant differences in the feeding proportions of food items or food item diversity indices were observed between the Banli and Bapen groups, the Banli groups extensively consumed ground‐supported kudzu (Pueraria montana var. lobata), a plant rarely recorded in the dietary preferences of the Bapen groups, implying that the large plants likely lacking in the fragmented limestone forests. Our findings provide evidence of the major impact of habitat fragmentation on the dietary composition of white‐headed langurs, highlighting the need of considering the possibility that the habitats of the white‐headed langurs have all undergone extreme fragmentation, inferring the conservation efforts should prioritize protecting native vegetation and reducing human disturbance. [ABSTRACT FROM AUTHOR]

Rangelands in the southwestern United States represent a current stronghold for northern bobwhite (Colinus virginianus); however, bobwhite populations in rangelands exhibit extreme inter‐annual variability in abundance in relation to fluctuating weather patterns. Recent declining bobwhite population trends within this region have led to the supposition that landscape‐scale processes, such as habitat loss and fragmentation and predation from increased raptor abundance, may be acting in conjunction with weather to reduce bobwhite populations. Our objective was to determine the relative effects of these factors on bobwhite populations in the rangeland environments of Texas and Oklahoma, USA. We obtained publicly available datasets for bobwhite counts (Breeding Bird Survey, state‐agency roadside counts), weather (PRISM), land cover (National Land Cover Database), and raptors (Christmas Bird Counts) for 3 5‐year periods (1990–1994, 1999–2003, 2009–2013). Data were collected at route and landscape scales based on routes within the Rio Grande Plains region of Texas and the Central Mixed Grass Prairie region of Texas and Oklahoma. We used generalized linear mixed models with a backward selection approach to determine top models for each dataset based on scale and ecoregion. Covariate relationships with bobwhite abundance followed expected patterns, with positive relationships with habitat, precipitation, and minimum temperatures and negative relationships with maximum temperatures and raptor abundance. Weather variables were the factors most consistently selected within both regions, while minimum winter temperature was overall the top variable. These relationships occurred within a landscape still containing relatively vast amounts of unfragmented bobwhite habitat (>60% rangeland; >15 million ha). Management within these regions should be focused on retaining habitat at a broad scale, while managing for suitable cover at a local scale to help mitigate weather effects. [ABSTRACT FROM AUTHOR]

Despite the significance of saproxylic beetle species for ecosystems, the investigation of fine‐scale population genetics within the stag beetle, Lucanus cervus, remains notably limited. Because of their limited dispersal distances and habitat fragmentation, high genetic structure and low genetic diversity are expected in its populations.To evaluate the impact of habitat fragmentation on genetic diversity and structure, we examined 150 specimens of L. cervus from three sites in western Poland: two forest stands and one stand located in an Oak avenue. We utilised 19 microsatellite DNA loci for this examination.Results of neighbour‐joining analysis and principal coordinates analysis, values of differentiation indexes (G'ST, D(Jost) and FST) and rare/private allele frequencies indicated weak genetic differentiation among individuals collected from the tree sites. A spatial component to the genetic structure was identified through STRUCTURE (LOCPRIOR), isolation by distance tests and spatial autocorrelation analysis. The genetic diversity remained relatively high (HE: 0.49–0.51), with no inbreeding observed and no significant differences in mean relatedness among individuals from sampling sites.Limited genetic differentiation between the individuals of L. cervus from the investigated sites may result from a lag time since fragment isolation, unrestricted gene flow and marker/sample size limitations. Though weak, the significant differentiation between two of the sites may be linked to environmental differences and distance. Genetic data support treating individuals from forests as a single management unit. Non‐invasive sampling suffices for genetic studies, but achieving balanced sampling is crucial for precise historical demography estimates of endangered species. [ABSTRACT FROM AUTHOR]

Juvenile survival is critical to population persistence and evolutionary change. However, the survival of juvenile plants from emergence to reproductive maturity is rarely quantified. This is especially true for long‐lived perennials with extended pre‐reproductive periods. Furthermore, studies rarely have the replication necessary to account for variation among populations and cohorts. We estimated juvenile survival and its relationship to population size, density of conspecifics, distance to the maternal plant, age, year, and cohort for Echinacea angustifolia, a long‐lived herbaceous perennial. In 14 remnant prairie populations over seven sampling years, 2007–2013, we identified 886 seedlings. We then monitored these individuals annually until 2021 (8–15 years). Overall, juvenile mortality was very high; for almost all cohorts fewer than 10% of seedlings survived to age 8 or to year 2021. Only two of the seedlings reached reproductive maturity within the study period. Juvenile survival increased with distance from the maternal plant and varied more among the study years than it did by age or cohort. Juvenile survival did not vary with population size or local density of conspecific neighbors. Our results suggest that low juvenile survival could contribute to projected population declines. [ABSTRACT FROM AUTHOR]

Optimizing habitat restoration success requires understanding how restoration location and design enhance the persistence and function of a restored habitat. Particular attention to the configuration of structure and its interaction with landscape‐scale processes is critical for enhancing the habitat value of restored areas. We monitored six subtidal restored oyster reefs in Pamlico Sound, North Carolina, United States, to identify how oyster demographics responded to initial habitat characteristics (e.g. reef area, volume, vertical relief, and perimeter‐to‐area ratio) and how changes in habitat characteristics over time altered suitability for oysters. Changes in reef habitat were measured by repeated mapping using bathymetric and side‐scanning sonar systems. A 2‐year time series of oyster demographic data quantified oyster response to habitat changes over time. All reefs provided habitat for the settlement and growth of oysters. Within 2 years of restoration, relative differences in oyster recruitment and survival emerged and were related to variations in reef location and two‐dimensional habitat characteristics among reefs, namely reef area and perimeter‐to‐area ratio. Larger reefs that were less fragmented resisted burial from sedimentation and enhanced oyster densities and biomass relative to smaller, more fragmented reefs that became heavily sedimented and failed to support oyster recruitment and survival. Positive feedback mechanisms between habitat characteristics and oyster recruitment success were established within 1 year of restoration and were likely driven by landscape‐scale processes such as sediment dynamics and larval supply. To improve restoration success, we recommend creating larger reef surfaces with low perimeter‐to‐area ratios in areas that promote habitat persistence. [ABSTRACT FROM AUTHOR]

Context: The process of urbanisation results in dramatic landscape changes with long-lasting and sometimes irreversible consequences for the biota as urban sensitive species are eliminated. The Australian brush-turkey (Alectura lathami) is a recent urban colonist despite atypical traits for an urban adapter. Contrary to observed range declines and initial reports of decreased reproductive success in cities, Australian brush-turkeys have increased their range in urban areas. Aims: Historical atlas and present citizen science data were used to examine the changing distribution of the Australian brush-turkey at continental and city scales, and the changing land use in urban areas occupied by the species. We assess which environmental and landscape features are driving observed distribution changes over time. Methods: We describe and map changes at the continental scale between 1839–2019. We then assessed colonisation of the cities of Brisbane and Sydney (located 900 km apart) over the period 1960–2019. At the city scale, we quantified the changing land use within Australian brush-turkey occupied areas over time using classification of satellite imagery. Key results: The Australian brush-turkey's geographical range has shifted over the last century, with the species receding from the western and southwestern parts of their range, while expanding in the northwest. Areas occupied in the cities of Brisbane and Sydney have expanded, with more recently occupied areas containing less vegetation and more developed land than previously occupied areas. Conclusions: Our results confirm that Australian brush-turkeys are successfully colonising urban areas, including major cities, and are likely to continue moving into urban areas, despite declines elsewhere in their natural range. The species is not limited to suburbs with a high proportion of greenspace, as Australian brush-turkeys are increasingly occurring in highly developed areas with limited vegetation. Implications: This study highlights that species which were locally extirpated from urban areas, and thought to be unlikely candidates for recolonisation, can successfully occupy human modified habitats. Successful expansion is likely to be associated with key behavioural traits, urban greening, and legal protection from human persecution. The Australian brush-turkey is a recent urban colonising species despite atypical traits for urban adaption, often causing human–wildlife conflict due to their digging behaviour. We outline historical changes in the species distribution at multiple scales and show their range has shifted over time, with an overall increase in major cities. Brush-turkeys are occupying increasingly developed areas, suggesting they are not limited to suburban areas with high greenspace cover and will continue to move into suburban areas. Photograph by Jenny Kelly. [ABSTRACT FROM AUTHOR]

Maintaining biodiversity in agricultural landscapes is a major challenge for environmental protection in Europe. Vineyards rely heavily on agrotechnical interventions such as herbicide use and tillage for weed control, which affect biodiversity and can lead to soil erosion and resistant weed populations. The fragmentation of agricultural landscapes affects biodiversity by altering community composition and often reducing plant population sizes and genetic diversity. However, it can also increase the abundance of certain species and enhance population resilience to environmental change. Vineyards can support high levels of biodiversity and provide ecosystem services due to their semi-natural habitat structure. This research evaluates vegetation biodiversity using phytosociological relevés in different vineyards. Our results show that species richness and biodiversity are significantly influenced by vineyard age and management type. This study highlights differences in the representation of plant functional groups, with perennial taxa in grassy inter-row contributing to anti-erosion functions and serving as food sources for pollinators. The root zone around vine trunks shows an increase in invasive species with vineyard age, posing a risk to the agroecosystem. Vineyards predominantly follow a ruderal ecological strategy, using nutrients and light efficiently, while tolerating management disturbances. Understanding these dynamics is critical for developing sustainable vineyard management practices that support biodiversity and ecological resilience, counteract the homogenization of agricultural landscapes, and promote the coexistence of viticulture and species-rich ecosystems. [ABSTRACT FROM AUTHOR]

The conversion of native habitats into anthropogenic ones compromises the original composition and configuration of the landscapes, influencing ecological dynamics and affecting biodiversity. Increasingly, landscape ecology has shown that these effects can only be understood if they are accessed at adequate spatial scales, as the scale at which landscape structure is evaluated influences species responses. Here, we investigated how three variables of landscape composition (proportion of forest, coffee crop, and pasture) and two of configuration (number of fragments and mean nearest neighbor distance) interfere with the richness and composition of medium- and large-sized mammals, considering a multiscale approach. We recorded medium- and large-sized mammal species in 13 landscapes with predominant matrices of coffee and pasture in Minas Gerais, Brazil. Then, we built distance-based linear models to identify the scale of effect of each landscape variable for both response variables considering eight scales (from 250 m to 2000 m). Finally, we verified the influence of the landscape on the richness and composition of mammals, considering the landscape variables in their respective scales of effect. We found 67% of the probable species occurring in the region. The scales of effect varied among landscape variables, probably due to the fact that different variables affect different aspects of organisms' ecological requirements. The proportion of pasture in the landscape explained the variation in species richness, while the proportion of forest explained the variation in species composition. In addition, the proportion of pasture in the landscape had a positive influence on species richness, indicating that this matrix may favor the presence of generalist species of habitat and/or this result is due to the higher concentration of species in the fragments immersed in this matrix. These results suggest that considering different responses to biodiversity is important to understand different aspects of the landscape's influence on biodiversity. In addition, the composition of the landscape is fundamental for the perpetuation of species and, therefore, both forest cover and types of matrices in the landscape must be considered to improve species conservation strategies. Finally, generalizing a spatial scale can lead to misinterpretations about the influence of the landscape on biodiversity. [ABSTRACT FROM AUTHOR]

Anthropogenic fragmentation of habitat is considered to be a critical factor contributing to the decline of species. However, a general consensus on the degree to which habitat loss and what has been called "habitat fragmentation per se" contribute to the loss of species diversity has not yet emerged. For empirical and theoretical reasons the topic has recently attracted renewed attention, thus reviving the "single large or several small" (SLOSS) debate. To study the effect of fragmentation per se, we use a spatially explicit and continuous, competitively neutral simulation model with immigration from a regional pool. The model accounts for the influence of ecological drift and intrafragment species clustering (due to limited dispersal) on local (plot) and global (landscape) diversity. We find that fragmentation increases global diversity but decreases local diversity, prominently so if fragments become more isolated. Cluster formation is a key mechanism reducing local diversity. By adding external disturbance events that lead to the occasional extinction of entire communities in habitat fragments, we show that the combined effect of such extinctions and cluster formation can create nonlinear interactive effects of fragmentation and fragment isolation on diversity patterns. We conclude that while in most cases fragmentation will decrease local and increase landscape diversity, universal predictions concerning the SLOSS debate should be taken with care. [ABSTRACT FROM AUTHOR]

Recent international agreements have strengthened and expanded commitments to protect and restore native habitats for biodiversity protection ("area‐based biodiversity conservation"). Nevertheless, biodiversity conservation is hindered because how such commitments should be implemented has been strongly debated, which can lead to suboptimal habitat protection decisions. We argue that, despite the debates, there are three essential principles for area‐based biodiversity conservation. These principles are related to habitat geographic coverage, amount, and connectivity. They emerge from evidence that, while large areas of nature are important and must be protected, conservation or restoration of multiple small habitat patches is also critical for global conservation, particularly in regions with high land use. We contend that the many area‐based conservation initiatives expected in the coming decades should follow the principles we identify, regardless of ongoing debates. Considering the importance of biodiversity for maintenance of ecosystem services, we suggest that this would bring widespread societal benefits. [ABSTRACT FROM AUTHOR]

Environmental change is disrupting mutualisms between organisms worldwide. Reported declines in insect populations and changes in pollinator community compositions in response to land use and other environmental drivers have put the spotlight on the need to conserve pollinators. While this is often motivated by their role in supporting crop yields, the role of pollinators for reproduction and resulting taxonomic and functional assembly in wild plant communities has received less attention. Recent findings suggest that observed and experimental gradients in pollinator availability can affect plant community composition, but we know little about when such shifts are to be expected, or the impact they have on ecosystem functioning. Correlations between plant traits related to pollination and plant traits related to other important ecosystem functions, such as productivity, nitrogen uptake or palatability to herbivores, lead us to expect non‐random shifts in ecosystem functioning in response to changes in pollinator communities. At the same time, ecological and evolutionary processes may counteract these effects of pollinator declines, limiting changes in plant community composition, and in ecosystem functioning. Despite calls to investigate community‐ and ecosystem‐level impacts of reduced pollination, the study of pollinator effects on plants has largely been confined to impacts on plant individuals or single‐species populations. With this review we aim to break new ground by bringing together aspects of landscape ecology, ecological and evolutionary plant–insect interactions, and biodiversity–ecosystem functioning research, to generate new ideas and hypotheses about the ecosystem‐level consequences of pollinator declines in response to land‐use change, using grasslands as a focal system. Based on an integrated set of seven hypotheses, we call for more research investigating the putative pollinator‐mediated links between landscape‐scale land use and ecosystem functioning. In particular, future research should use combinations of experimental and observational approaches to assess the effects of changes in pollinator communities over multiple years and across species on plant communities and on trait distributions both within and among species. [ABSTRACT FROM AUTHOR]

Revealing the relationship between the mating system (i.e., the outcrossing/inbreeding degree) and the fitness of seeds in tree species under wild conditions is essential for understanding the ecological adaptability and evolutionary stability of the species. This study collected open-pollinated seeds from seven wild populations of Pinus yunnanensis var. tenuifolia that exhibited fragmentation in the Nanpan–Hongshui River basin, an ecologically fragile area in China. The seeds and sprouts (germinated seeds) from 20 families were genotyped (24 seeds and 24 sprouts per family) using twelve microsatellite loci to reveal the genetic diversity, mating status, and effect of inbreeding on the three seed quality indicators (thousand-seed weight, germination rate, and germination potential). The three seed quality indicators differed significantly between families (p < 0.001). Higher values of genetic diversity (except the observed heterozygosity) were observed in the sprout group than those in the seed group. Families from different populations showed a notable genetic differentiation (Φst = 0.12), and a large part of families from the common populations had a high degree of coancestry, which signified that the current habitat fragmentation is limiting gene flow between populations. High levels of outcrossing rates (tm) were observed in both the seed group (tm = 0.974) and the sprout group (tm = 0.978), indicating that a low proportion of seeds were self-fertilized. Although there was a slightly higher single outcrossing rate (ts = 0.888) and a lower proportion of biparental inbreeding (tm − ts = 0.077) in sprouts compared to the seeds (ts = 0.871, tm − ts = 0.091), indicating that a part of inbred seeds were purged during the germination stage, curve fitting between the outcrossing rate and seed quality indicators showed that a certain degree of biparental inbreeding (ts between 0.89 and 0.91 and tm − ts between 0.09 and 0.11) did have a positive effect on seed germination ability. This highlights that excessive inbreeding or outbreeding seems to be unfavorable to seed viability. The peculiar relationship between seed viability and the mating system in P. yunnanensis var. tenuifolia was likely an evolutionary consequence of a trade-off between the nature of mixed mating and its specific ecological niche. [ABSTRACT FROM AUTHOR]

Dam construction and operation can result in serious disturbances to the downstream flow regime and fluvial process, river morphology and the river's ecological condition worldwide. To understand the effects of discharge and sedimentation on fish habitats and ecosystems, an ecohydraulic approach was applied to one of the mega hydropower schemes in the downstream Lancang River (Tibet). The approach comprised a dam operation module with high flow and sediment transport and the application of a dynamic fish habitat model for assessing habitat fragmentation of two targeted fish species: Schizothorax prenanti (S. prenanti) and Schizothorax davidi (S. davidi). The hydrodynamics of the river system and the assessed fish habitat show a significant impact of dam construction and operation on the downstream riverine ecosystem, in which fish habitats were found rapidly deteriorated with the destruction of feeding and reproductive grounds. To improve fish habitat after dam construction, the sediment supplement was applied to the river and shown to be a useful restoration strategy, which recovers the habitat fragmentation of target fish. Our model not only is useful to predict dam operation impacts on the Lancang River's ecological status but also shows great potential in mitigating hydropower‐induced environmental impacts and developing river conservation guidelines worldwide. [ABSTRACT FROM AUTHOR]

Background: Anthropogenic activities significantly impact natural ecosystems, leading to alterations in plant and pollinator diversity and abundance. These changes often result in shifts within interacting communities, potentially reshaping the structure of plant-pollinator interaction networks. Given the escalating human footprint on habitats, evaluating the response of these networks to anthropization is critical for devising effective conservation and management strategies. Methods: We conducted a comprehensive review of the plant-pollinator network literature to assess the impact of anthropization on network structure. We assessed network metrics such as nestedness measure based on overlap and decreasing fills (NODF), network specialization (H2'), connectance (C), and modularity (Q) to understand structural changes. Employing a meta-analytical approach, we examined how anthropization activities, such as deforestation, urbanization, habitat fragmentation, agriculture, intentional fires and livestock farming, affect both plant and pollinator richness. Results: We generated a dataset for various metrics of network structure and 36 effect sizes for the meta-analysis, from 38 articles published between 2010 and 2023. Studies assessing the impact of agriculture and fragmentation were well-represented, comprising 68.4% of all studies, with networks involving interacting insects being the most studied taxa. Agriculture and fragmentation reduce nestedness and increase specialization in plant-pollinator networks, while modularity and connectance are mostly not affected. Although our meta-analysis suggests that anthropization decreases richness for both plants and pollinators, there was substantial heterogeneity in this regard among the evaluated studies. The meta-regression analyses helped us determine that the habitat fragment size where the studies were conducted was the primary variable contributing to such heterogeneity. Conclusions: The analysis of human impacts on plant-pollinator networks showed varied effects worldwide. Responses differed among network metrics, signaling nuanced impacts on structure. Activities like agriculture and fragmentation significantly changed ecosystems, reducing species richness in both pollinators and plants, highlighting network vulnerability. Regional differences stressed the need for tailored conservation. Despite insights, more research is crucial for a complete understanding of these ecological relationships. [ABSTRACT FROM AUTHOR]

Habitat loss and forest fragmentation are often linked to increased pathogen transmission, but the extent to which habitat isolation and landscape connectivity affect disease dynamics through movement of disease vectors and reservoir hosts has not been well examined. Tick-borne diseases are the most prevalent vector-borne diseases in the United States and on the West Coast, Ixodes pacificus is one of the most epidemiologically important vectors. We investigated the impacts of habitat fragmentation on pathogens transmitted by I. pacificus and sought to disentangle the effects of wildlife communities and landscape metrics predictive of pathogen diversity, prevalence and distribution. We collected pathogen data for four co-occurring bacteria transmitted by I. pacificus and measured wildlife parameters. We also used spatial data and cost-distance analysis integrating expert opinions to assess landscape metrics of habitat fragmentation. We found that landscape metrics were significant predictors of tick density and pathogen prevalence. However, wildlife variables were essential when predicting the prevalence and distribution of pathogens reliant on wildlife reservoir hosts for maintenance. We found that landscape structure was an informative predictor of tick-borne pathogen richness in an urban matrix. Our work highlights the implications of large-scale land management on human disease risk.

IntroductionHeterostyly is a genetically controlled style polymorphism, that plays an important role in promoting outcrossing and improving reproductive fitness. Although distyly is often studied in plants of the Rubiaceae family, little attention has been paid to the reproductive strategies of distylous species in fragmented habitats. Here, We report for the first time the growth of Ophiorrhiza alatiflora, a type distylous species, in karst areas and evaluate its reciprocity between long styled morph and short one. We analyze the two distyly morph differences in the ancillary polymorphic of flowers and explore their reproductive strategy in fragmented habitats.MethodsIn this study, we measured the floral characteristics of different morphs and performed differential secondary metabolite analysis on different morphs and tissue organs; Different pollination treatments were carried out to observe the fruit set, pollen germination, and pollen tube elongation of O. alatiflora.Results and discussionOur research indicates that O. alatiflora is a typical distylous plant for the distyly has high reciprocity. Both morphs exhibit the highest fruit set of intermorph outcrossing; The pollen germination and pollen tube elongation experiments have also demonstrated that the affinity of pollen from intermorph outcrossing is highest, regardless of whether it is the long or short morph as the maternal parent; Meanwhile, O. alatiflora is an incompletely self-incompatible plant that exhibits a certain degree of self-pollination and intramorph outcrossing, which may be one of the important means to ensure sustainable reproduction in severely disturbed habitats. In the ancillary polymorphic of flowers, L-morphs flowers produce more pollen, and S-morph flowers produce more ovules to improve their male-female fitness and compensate for the asymmetry of pollen flow; Compared with S-morphs, L-morphs contain significantly higher levels of several kinds of terpenoids. S-morphs produce more flavonoids than L-morphs. The differences in secondary metabolites between L-morphs and S-morphs are mainly reflected in the different nutritional organs (including stems and leaves). Overall, our work has revealed the unique reproductive strategy of O. alatiflora in fragmented habitats based on the characteristics of distyly, verifying the hypothesis that the distyly of O. alatiflora promotes outcrossing and avoids male-female interference, improving male-female fitness and this is the first time in the Ophiorrhiza genus.

Urbanization has profound effects on wildlife. Although some species benefit or even thrive in urban environments, most species respond differently to the varying degrees of disturbance that can be found across an urbanized landscape. Quantifying the effects of urbanization in wildlife distributions, however, is complicated: species vary in their patterns of presence/absence, abundance, and detectability across spatial and temporal scales, e.g., daily, seasonal, or throughout the annual cycle. Here, we use occupancy models to offer a realistic approach to the study of populations of urban owls. Most studies on owl population dynamics have not considered temporal variation in occupancy between seasons or assess the uneven effects of urbanization along a habitat gradient. We investigated the seasonal habitat associations of mottled owls along an urban gradient in the Neotropical city of Xalapa, Veracruz, Mexico. Using high-resolution satellite images and object-based image classification techniques, were analyzed the relationship between different vegetation and environmental characteristics with the occupancy of mottled owls. We employed different sampling techniques, including playback surveys and silent listening periods, to detect the presence or absence of owls along a gradient from highest to lowest urbanization. Environmental data and different vegetation types were used to analyze the habitat associations of mottled owls during January (late non-breeding season) and May (late breeding season) of 2023. In total, we detected 68 mottled owls during the non-breeding season and 102 during the breeding season, with higher detection rates in areas with >28 % forest surface. Our results revealed that the best occupancy model included forest and forest division (occupancy), ambient noise and moonlight (detection) for the non-breeding season, as well as urban, forest, grass, and forest division (occupancy), and noise (detection) for the breeding season. The percentage of forested and grass areas positively influenced mottled owl occupancy while the percentage of urbanization and forest division influenced it negatively. Moonlight was positively related to mottled owl detection, while ambient noise had a negative effect on detection probabilities of mottled owls during both seasons. Forested areas emerged as pivotal for owl occupancy, indicating their sensitivity to forest changes along the urban gradient. With urban areas increasing, the interplay between forest division, ambient noise, and moonlight unveils critical insights into mottled owl behavior and habitat dynamics, underscoring the necessity for informed conservation strategies amidst urban expansion. Future research should survey different years to provide a more robust assessment of the dynamic occupancy of mottled owls in Neotropical urban gradients.