Ecology and Evolution最新文献

Seed dispersal research has expanded significantly over time, leading to a proliferation of terms relating to dispersal modes that has resulted in terminological confusion. This viewpoint identifies the primary concerns in this regard: synonymy (multiple terms used for the same mode) and polysemy (the same term used for distinctly different modes). Such inconsistencies hinder conceptual clarity, impede literature syntheses, and obstruct the practical application of seed dispersal ecology. To address these challenges, we propose two complementary pathways. First, we suggest organizing a world cafe to foster consensus-building among researchers engaging with seed dispersal ecology. Second, we introduce the Diaspore-Vector-Review (DVR) framework as a decision-support tool to prioritize nomenclature for non-overlapping dispersal mechanisms rather than agent-centric definitions of dispersal modes. By refining the branching of subclasses from classical modes into a coherent, hierarchical classification system, we can ensure greater scientific rigor and real-world impact of seed dispersal research.

Advances in fine-scale movement modeling of soaring birds can aid efforts to understand and resolve the impacts of anthropogenic activities on such birds. Soaring birds often rely on underlying terrain and low-altitude updrafts to govern their flights at rotor-swept altitudes (≤ 200 m above ground level), which puts them at risk of collision with wind turbines. We developed a data-driven Markov model at 1-s resolution that predicts the fine-scale flight behavior of golden eagles (Aquila chrysaetos) as a function of ecological covariates at the current location as well as those within an eagle's line of sight. We only considered ecological covariates that are readily available in real-time (ground elevation and wind conditions). Latent factors (age, sex, species, behavioral intent, migratory status) were intentionally left out of the model. We calibrated the model using golden eagle telemetry data collected in two different ecoregions of the United States. Given a starting location, the calibrated model simulates multiple stochastic 3D paths to produce a time-explicit and spatially explicit risk map of turbine collisions. We discovered an empirical relation between the rate of change of heading and the orographic updraft conditions within an eagle's line of sight. Our model performed most effectively when predicting predominantly-soaring flights at rotor-swept altitudes during wind conditions in which turbines are likely to be operational. The calibrated model could be used in concert with automated eagle detection and turbine curtailment technologies. Specifically, once an eagle is detected by those systems, our model could then provide accurate predictions of turbines the eagle is likely to interact with in the near term.

Freshwater ecosystems are impacted by anthropogenic stressors, resulting in roughly one-third of freshwater fauna being threatened with extinction. The Neuse River Waterdog (Necturus lewisi) is a large aquatic salamander endemic to the Neuse and Tar-Pamlico River basins of eastern North Carolina, USA, and it was listed as threatened under the federal Endangered Species Act in 2021. Habitat degradation has been identified as the dominant threat driving N. lewisi occurrence, and its effect may be delayed. The USFWS Draft Recovery Plan classified investigation into the species' occurrence dynamics (colonization/extinction) as a high priority action. We hypothesized that extinction probabilities would decrease in high quality local instream habitats, increase with high proportions of disturbed land cover in the contributing watershed, and increase in years with intense droughts. We evaluated these hypotheses within a dynamic occupancy modeling framework using five consecutive years of detection/non-detection data collected across 176 locations. We derived estimates of annual occurrence, turnover, and equilibrium occupancy (stability) to investigate if spatial responses to threats were delayed-an extinction debt. The top-ranked model supported the hypotheses on drivers of site-specific extinction probabilities, including a negative effect of habitat quality, positive effect of developed land cover in the watershed, and positive effect of annual drought intensity. The derived estimates broadly indicated that annual occurrence was highest in rural subpopulations (i.e., management units), turnover was greatest in urban subpopulations, and equilibrium occupancy was lower than required to maintain stability in most subpopulations of the Neuse River basin. The estimated occurrence dynamics and their derived quantities suggested an extinction debt in urban subpopulations that may be accelerated by stochastic drought events. This study describes a novel use of the dynamic occupancy model framework within an extinction debt context and provides partnering conservation agencies with information important to guiding recovery of the Neuse River Waterdog.

Gene flow affects the distribution of genetic variation of a species over time and thus can be crucial for a population's persistence and adaptive capacity. Given the importance of gene flow, it is key to understand the connectivity and genetic differentiation between populations of species with small and segregated breeding populations that are facing population declines, such as many long-distance migratory birds. In this study, we explored population structure in Hudsonian Godwits (Limosa haemastica) from two geographically distinct breeding areas in the North American sub-Arctic and two nonbreeding areas in South America using nuclear microsatellites. Despite being spatially and temporally segregated during most of the annual cycle, our results indicate no evidence of population differentiation between breeding populations, nor clustering between individuals from breeding and nonbreeding populations connected by migration. Considering the phenology of the species, godwits from both breeding populations could co-occur during southward migration and/or throughout the oversummering period, likely in the Las Pampas ecoregion of Argentina. As with many other long-distance migratory shorebirds, immature godwits stay in their nonbreeding areas until sexual maturity is reached, during which time they can explore, interact, and follow flocks of adults to different nonbreeding areas, thus increasing the chances of mixing between populations. This highlights the importance of recognizing the key role of early life period within the full life cycle of migratory birds for understanding their demography and evolutionary potential.

Rapid urbanisation has led several spider species to adapt to synanthropic microhabitats and establish large populations outside of their native ranges. In Ireland, the establishment and widespread distribution of the Noble false widow spider Steatoda nobilis (Araneae: Theridiidae) (Thorell, 1875) has raised questions about its impact on native spider populations across the country. Through an extensive field survey of six urban centres over an 11-month period, we sought to establish population demographics for S. nobilis and other synanthropic spiders in Ireland for the first time. We surveyed fence microhabitats for both spider abundance and diversity to determine the influence of variables such as prey availability and climate. Of the 20 identifiable species observed, S. nobilis and the missing sector orb weaver Zygiella x-notata (Clerck, 1757) typically made up more than 80% of the spider abundance regardless of location surveyed, including two new Irish counties where S. nobilis had previously not been recorded but is now well established (Co. Mayo and Co. Sligo). Our results also indicated that the diversity of synanthropic spiders is significantly affected by seasonality and prey availability, but largely unaffected by daily weather conditions.

Carya luodianensis Y.B. Yang & M.T. An (Juglandaceae), a new species from Luodian County, Guizhou Province, China, is described and illustrated based on morphological and molecular data. Morphologically, this species resembles C. kweichowensis but can be easily distinguished by its rusty brown buds, 5-7 leaflets, a greater number of lateral veins (12-21 pairs), pubescent anthers, and nut shell bearing four faint longitudinal ridges. Molecular phylogenetic analysis based on complete chloroplast genome sequences indicates that C. luodianensis is sister to C. kweichowensis. The plastome of C. luodianensis, with a total length of 175,255 bp, exhibits a typical quadripartite structure and consists of 78 protein-coding genes (PCGs), 30 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Notably, a marked expansion of the inverted repeat (IR) region (40,956 bp) and contraction of the small single-copy (SSC) region (3553 bp) are detected, accompanied by the translocation of several genes from the SSC region to the IR regions, resulting in increased gene copy numbers and reduced GC content. Comparative plastome analyses further reveal the conservation and differentiation between C. luodianensis and its closely related species, particularly in genome size, gene order, and repeat sequence distribution. Collectively, the unique morphological traits, plastid genome features, and phylogenetic placement strongly support the recognition of C. luodianensis as a distinct new species and highlight its evolutionary divergence within Carya.

Grasslands represent an important source of vegetative diversity and provide a range of important ecosystem services. Semi-natural grasslands in Europe face a variety of threats due to changing management practices and other anthropogenic pressures. This study investigates vegetative changes in 12 semi-natural grassland sites in Ireland over an approximately 15-year period. Sites for three habitat types (GS1-dry calcareous & neutral grassland, GS3-dry-humid acid grassland and GS4-wet grassland) were selected from the 2007-2012 Irish Semi-natural Grassland Survey and resurveyed in 2023. The resurveyed sites showed a minor shift in vegetative composition in terms of species richness, but non-metric multidimensional scaling suggests that the grasslands are increasingly homogenous with habitat types having become less distinct. While both species losses and gains were observed, almost half of the forb species decreased in frequency, and some of the rarer species were lost. This raises concerns about the mid- and long-term diversity of Irish semi-natural grasslands and suggests that careful management aimed at protecting diversity is required.

Coyotes (Canis latrans) expanded across eastern North America in the last century and are ecological generalists capable of thriving across diverse habitats. Broad genetic surveillance has reported little spatial genetic patterning for this highly dispersive species. Here, we explore the genome-wide signatures of spatial patterns found in a 10-year study of 1199 coyotes from northeastern United States, with a temporal analysis of Pennsylvania coyotes. Despite their broad dispersal capability, we detected subtle but significant population structure, with two genetic clusters that have a weak clinal transition zone. This partitioning aligned qualitatively with patterns of human population density and activity. We inferred that gene flow between these genetic groups was associated with two different demographic expansions of coyotes eastward, south along the Great Lakes and separately along the northern Lakes towards northeastern United States. We identify Pennsylvania as a recent contact zone. Morphometric analyses revealed only modest differentiation between clusters and no robust temporal shifts, though a weak trend of increased body mass was noted in southwestern males. Collectively, our findings demonstrate that anthropogenic features likely influence fine-scale cryptic population structure, even in a highly dispersing and widespread mesopredator.

Human-wildlife conflicts frequently occur at forest-agriculture interfaces, particularly in fragmented landscapes where wildlife movement corridors intersect with farmland. This study evaluated the effectiveness of a short fence in reducing seasonal incursions by wild boar (Sus scrofa) and Korean water deer (Hydropotes inermis argyropus) into farmland at Baekbong Mountain, Namyangju City, Gyeonggi Province, South Korea, from January 2021 to February 2022. Using camera trap detections and UAV-derived environmental data, we developed seasonal habitat suitability models with Maxent and conducted connectivity analyses using Omniscape to identify potential movement corridors. A 200 m fence was installed at a predicted hotspot, and additional camera traps were used to monitor changes in wildlife movement. Trails and roads were identified as key environmental variables influencing habitat suitability for both species. After fence installation, the preferred corridor used by wild boar near a mud pool was effectively blocked, whereas Korean water deer continued to access the same location. Seasonal distribution changes were more pronounced for wild boar, with their range expanding beyond the fenced area. Our results suggest that even relatively short fences can effectively deter wild boar movement while having minimal impact on water deer, highlighting the importance of species-specific ecological considerations when implementing mitigation measures. These findings provide practical insights for farmers and land managers seeking to reduce wildlife incursions and mitigate human-wildlife conflicts in urban-fringe ecosystems.

Managing biological invasions is one of the top priorities of biodiversity conservation. Invasive plants are a well-known threat to native plant and animal communities, and understanding their ecological impacts is critical to developing individualized management strategies. While much is known about the impacts of invasive plants, there are still questions about the per capita effects along invasion abundance gradients across levels of biological organization. In this study we investigate how the ecological impacts of the invasive grass Bothriochloa ischaemum vary across a gradient of invasion and whether effects are consistent across population (abundance and functional traits of a dominant native grass, Schizachyrium scoparium) and community (species richness and composition) levels. We found that most of the ecological impacts of B. ischaemum scale linearly with its abundance across population and community levels. Increasing invasion reduces the height and abundance of the dominant native S. scoparium individuals and shifts their functional trait composition. Increasing invasion also reduces cover of native C₃ and C₄ grasses, total foliar cover, subdominant foliar cover, species richness, and leads to shifts in species and functional group composition. However, the impact on legume abundance saturated at low invader abundance (1%-15% cover) and remained constant as invader abundance increased. We show that the direct ecological impacts of invasive species may be compounded by shifts in the functional traits of dominant native species toward more conservative traits and shifts in species and functional group composition, leading toward a shift in population and community structure and function.