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Navel orangeworm, Amyelois transitella (Walker), is a key pest in Californias almonds, pistachios, and walnuts. This insects strong dispersal capacity can potentially undermine the efficacy of localized management efforts. The timing and extent of A. transitella movement between orchards remain unclear, and more studies are needed to better characterize its landscape ecology. Mark-release-recapture studies offer a potential solution but require a reliable insect marker that is durable, easily identifiable and has minimal impacts on A. transitella longevity and flight ability. To address this, we evaluated 4 colors (red, blue, green, and yellow) of a fluorophore marker (SmartWater) for adult A. transitella. We conducted laboratory assays to assess moth flight ability and mortality, as well as marker persistence over time using both quantitative (plate reader) and qualitative (visual observation) fluorophore detection methods. Results demonstrated that none of the 4 colors negatively affected A. transitella flight ability or mortality. Green and yellow markers were persistent and readily identified by both detection methods, unlike blue and red markers. Although marker degradation was observed over time with the quantitative method, a high percentage of moths (70.3%) retained green and yellow markers after 14 days. In contrast, these markers did not show significant degradation using the qualitative method, with over 94.2% of moths showing fluorescence 14 days postmarking. These findings highlight the strong potential of green and yellow markers for field studies with A. transitella. We discuss their use in future mark-release-recapture studies and compare the 2 fluorophore detection methods.

Dispersal is an important individual decision which may influence individual fitness as well as population viability. The social cohesion hypothesis posits more social individuals remain at home, which is supported by prior work across taxa. However, how the sociality and connectivity of the group an individual resides in-their group social structure-relates to dispersal decisions has not been explored. We extend the social cohesion hypothesis to predict individuals residing in more social groups would remain at home, and we quantified the affiliative and agonistic social network structure of female yellow-bellied marmots (Marmota flaviventer), a facultatively social ground-dwelling squirrel, where about half of all females disperse. Using mixed-effects models, we found no support for the hypothesis that affiliative group structure explained any variation in a marmots decision to disperse. We did find marmots in groups with less agonistic centralization (around one or few individuals) were less likely to disperse. The former finding may result from limited ability to perceive group structure whereas the latter may reflect individuals in less agonistically centralized groups are less likely to be reproductively suppressed. These results suggest individual dispersal decisions are more impacted by individual sociality and not that of their social group. Thus, the social cohesion hypothesis may not scale to the level of the group. Further work is required to determine whether dispersal decisions in obligately social species are influenced by group social structure.

Recent increases in frequency and intensity of warm water anomalies and marine heatwaves have led to shifts in species ranges and assemblages. Genomic tools can be instrumental in detecting such shifts. In the early stages of a project assessing population genetic structure in Pacific Sardine (Sardinops sagax), we detected the presence of Japanese Sardine (Sardinops melanosticta) along the west coast of North America for the first time. We assembled a high quality, chromosome-scale reference genome of the Pacific Sardine and generated low coverage, whole genome sequence (lcWGS) data for 345 sardine collected in the California Current Large Marine Ecosystem (CCLME) in 2021 and 2022. Fifty individuals sampled in 2022 were identified as Japanese Sardine based on strong differentiation observed in lcWGS SNP and full mitogenome data. Although we detected a single case of mitochondrial introgression, we did not observe evidence for recent hybridization events. These findings change our understanding of Sardinops spp. distribution and dispersal in the Pacific and highlight the importance of long-term monitoring programs.

Patterns of population connectivity shape ecological and evolutionary phenomena from population persistence to local adaptation and can inform conservation strategy. Connectivity patterns emerge from the interaction of individual behavior with a complex and heterogeneous environment. Despite ample observation that dispersal patterns vary through time, the extent to which variation in the physical environment can explain emergent connectivity variation is not clear. Empirical studies of its contribution promise to illuminate a potential source of variability that shapes the dynamics of natural populations. We leveraged simultaneous direct dispersal observations and oceanographic transport simulations of the clownfish Amphiprion clarkii in the Camotes Sea, Philippines, to assess the contribution of oceanographic variability to emergent variation in connectivity. We found that time-varying oceanographic simulations on both annual and monsoonal timescales partly explained the observed dispersal patterns, suggesting that temporal variation in oceanographic transport shapes connectivity variation on these timescales. However, interannual variation in observed mean dispersal distance was nearly 10 times the expected variation from biophysical simulations, revealing that additional biotic and abiotic factors contribute to interannual connectivity variation. Simulated dispersal kernels also predicted a smaller scale of dispersal than the observations, supporting the hypothesis that undocumented abiotic factors and behaviors such as swimming and navigation enhance the probability of successful dispersal away from, as opposed to retention near, natal sites. Our findings highlight the potential for coincident observations and biophysical simulations to test dispersal hypotheses and the influence of temporal variability on metapopulation persistence, local adaptation, and other population processes.

Dispersal of reproductive propagules determines recruitment patterns and connectivity among populations and can influence how populations respond to major disturbance events. Dispersal distributions can depend on propagule release strategies. For instance, the bull kelp, Nereocystis luetkeana, can release propagules (spores) from two heights in the water column (“bimodal release”): at the water surface, directly from the reproductive tissues (sori) on the kelp's blades, and near the seafloor after the sori abscise and sink through the water column. N. luetkeana is a foundation species that occurs from central California to Alaska and is experiencing unprecedented levels of population declines near its southern range limit. We know little of the kelp's dispersal distributions, which could influence population recovery and restoration. Here, we quantify how bimodal spore release heights affect dispersal outcomes based on a numerical model specifically designed for N. luetkeana. The model incorporates oceanographic conditions typical of the species' coastal range and kelp biological traits. With bimodal release heights, 34% of spores are predicted to settle within 10 m of the parental alga and 60% are predicted to disperse beyond 100 m. As an annual species, bimodal release heights can facilitate the local regeneration of adults within a source kelp forest while also supporting connectivity among multiple forests within broader bull kelp metapopulations. To leverage this pattern of bimodal spore dispersal in bull kelp restoration management, directing resources toward strategically located focal populations that can seed other ones could amplify the scale of recovery.

ObjectivesChimpanzees (Pan troglodytes) are patrilocal, with males remaining in their natal community and females dispersing when they reach sexual maturity. However, the details of female chimpanzee dispersal, such as their possible origin, are difficult to assess, even in habituated communities. This study investigates the utility of 87Sr/86Sr analysis for (1) assessing Sr baseline differences between chimpanzee territories and (2) identifying the status (immigrant or natal) of females of unknown origin within the territories of five neighboring communities in Taï National Park (Côte d'Ivoire).Materials and methodsTo create a local Sr isoscape for the Taï Chimpanzee Project (TCP) study area, we sampled environmental samples from TCP-established territories (n = 35). To assess dispersal patterns, 34 tooth enamel samples (one per individual) were selected from the Taï chimpanzee skeletal collection. 87Sr/86Sr analysis was performed on all 69 samples at the W.M. Keck Lab. The theoretical density and overlap of chimpanzee communities as well as generalized linear mixed models (GLMMs) were used to test each question.Results87Sr/86Sr ratios for natal male chimpanzees ranged from 0.71662 to 0.72187, which is well within the corresponding environmental baseline range of 0.70774-0.73460. The local Sr isoscapes fit was estimated with the root-mean-square error value, which was 0.0048 (22% of the whole 87Sr/86Sr data range). GLMMs identified significant differences in 87Sr/86Sr ratios between natal and unknown North community origin groups, suggesting that after 1980, females of unknown origin could be immigrants to North community (n = 7, z-ratio = -4.08, p = 0.0001, power = 0.94).DiscussionThis study indicates that 87Sr/86This study indicates that 87Sr/86Sr analysis can successfully identify immigrant females in skeletal collections obtained from wild chimpanzee communities, enabling the tracking of female dispersal patterns historically. There are, however, significant limitations within the scope of this study, such as (1) the absence of reliable maps for the TCP study area, (2) limited capacity for environmental sampling, (3) small sample sizes, and (4) tooth formation in wild chimpanzees.

Decisions to disperse from a habitat stand out among organismal behaviours as pivotal drivers of ecosystem dynamics across scales. Encounters with other species are an important component of adaptive decision-making in dispersal, resulting in widespread behaviours like tracking resources or avoiding consumers in space. Despite this, metacommunity models often treat dispersal as a function of intraspecific density alone. We show, focusing initially on three-species network motifs, that interspecific dispersal rules generally drive a transition in metacommunities from homogeneous steady states to self-organized heterogeneous spatial patterns. However, when ecologically realistic constraints reflecting adaptive behaviours are imposed-prey tracking and predator avoidance-a pronounced homogenizing effect emerges where spatial pattern formation is suppressed. We demonstrate this effect for each motif by computing master stability functions that separate the contributions of local and spatial interactions to pattern formation. We extend this result to species-rich food webs using a random matrix approach, where we find that eventually, webs become large enough to override the homogenizing effect of adaptive dispersal behaviours, leading once again to predominately pattern-forming dynamics. Our results emphasize the critical role of interspecific dispersal rules in shaping spatial patterns across landscapes, highlighting the need to incorporate adaptive behavioural constraints in efforts to link local species interactions and metacommunity structure. This article is part of the theme issue Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics.

The dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron-BA.1 variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the United States became increasingly significant. The number of detected introductions varied from 96 and 101 for Alpha and Delta to 39 for Omicron-BA.1. Most of these introductions left a low number of descendants (

Background: For many aquatic taxa, juvenile dispersal from spawning locations to rearing habitats is a critical process influencing individual fitness and population dynamics. However, our understanding of dispersal patterns in naturally spawning fish populations remains largely unknown due to the logistical challenges of tagging and tracking movement at early life stages. Methods: We quantified dispersal patterns of a spring-run Chinook Salmon (Oncorhynchus tshawytscha) population in NE Oregon, USA using genetic parentage-based tagging to trace juveniles captured from summer rearing habitats back to their maternal parent and associated spawning location (i.e., juvenile origin). We evaluated overall dispersal patterns, longitudinal trends across the watershed, and relationships between dispersal and biophysical factors, including thermal conditions, network-scale abundance estimates, and juvenile size-at-capture. Results: Overall dispersal of the 1326 juveniles (n sampled = 3388) assigned to a maternal parent (n = 64) was downstream-biased, but we estimated that 32% dispersed upstream and 29% moved into adjacent tributaries after initial mainstem dispersal. Dispersal distances were high relative to those found in other studies, with 25% of parr dispersing more than 0.9 km upstream (max = 10.6 km) and 25% dispersing more than 3.7 km downstream (max = 28.6 km). Analysis of dispersal patterns and potential drivers indicated that (1) dispersal distances, directional bias, and variability showed clear longitudinal trends from downstream to upstream origin locations, (2) temperature was a dominant driver of dispersal, with individuals originating from warmer sections of the mainstem typically moving to cooler mainstem sections or tributaries, and (3) dispersal distance was associated with larger size-at-capture for individuals that dispersed downstream, but not upstream. Conclusions: The widespread dispersal patterns exhibited in this population, including moving considerable distances upstream, downstream, and into tributaries, suggests that dispersal in naturally spawning fish populations may be more extensive and variable than currently recognized. We found that heterogeneity in biophysical conditions shaped within-population variability and riverscape dispersal patterns with important implications for subsequent fish habitat use, distribution, and size. This study provides an approach to evaluate patterns and drivers of dispersal in naturally spawning populations and inform conservation and restoration planning through better alignment with juvenile fish ecology. [ABSTRACT FROM AUTHOR]

Spatial-temporal variation in environmental conditions is ubiquitous in nature. This variation simultaneously impacts survival, reproduction, and movement of individuals and thereby the rate at which metapopulations grow. Using the tools of stochastic demography, the metapopulation growth rate is decomposed into five components corresponding to temporal, spatial, and spatial-temporal variation in fitness and spatial and spatial-temporal covariation in dispersal and fitness. While temporal variation in fitness always reduces the metapopulation growth rate, all other sources of variation can either increase or reduce the metapopulation growth rate. Increases occur either by reducing the impacts of temporal variation or by generating a positive fitness-density covariance where individuals tend to concentrate in higher-quality patches. For example, positive autocorrelations in spatial-temporal variability in fitness generate this positive fitness-density covariance for less dispersive populations but decrease it for highly dispersive populations (e.g., migratory species). Negative autocorrelations in spatial-temporal variability have the opposite effects. Positive covariances between movement and future fitness, on short or long timescales, increase growth rates. These positive covariances can arise in unexpected ways. For example, the win-stay, lose-shift dispersal strategy in negatively autocorrelated environments can generate positive spatial covariances that exceed negative spatial-temporal covariances. This decomposition of the metapopulation growth rate provides a way to quantify the relative importance of fundamental sources of variation for metapopulation persistence. [ABSTRACT FROM AUTHOR]

Social insects often share their colony with individuals of different relatedness levels and life stages. When no reproductive depression is in place, a female must choose whether to stay with her natal group and possibly limit her reproductive potential or leave to establish a new colony. The factors governing and following this decision are still largely unknown. The date stone beetle Coccotrypes dactyliperda (Curculiondae) resides in galleries carved inside date seeds. Sibling mating is common in this species. While most females in a natal group stay and raise their offspring with their sisters, some females leave to start a colony of their own, regardless of resources' availability within the natal group. In this study, we hypothesized that dispersing females should present physiological changes consistent with the anticipated challenges, including finding a host and egg laying, while the physiology of females that stay in the natal seed should demonstrate physiology related to cohabiting in an existing nest. To test our hypothesis, we examined the development of ovaries in 'stayers' and 'dispersers' females. In addition, we sequenced and analysed the transcriptome of pooled groups of 'stayers' and 'dispersers' sisters. Our physiological and transcriptomic results indicate that females who left the natal seed exhibit greater ovarian development. Our transcriptomic data revealed further differences between the two groups, including higher levels of expression of cuticle-related genes in the females that chose to stay in the natal nest. We discuss the possible roles of these genes in the continued life inside the natal nest. [ABSTRACT FROM AUTHOR]

Butterfly populations in Europe are declining, necessitating efficient conservation strategies. Understanding butterfly behaviour in relation to habitat quality is important, and one aspect is flight behaviour at habitat edges. This study investigates flight patterns of the marsh fritillary (Euphydryas aurinia) in relation to edges between intensively grazed and ungrazed habitat on Gotland, Sweden. We also examine the small-scale habitat utilization in relation to the abundance of host and nectar plants. Observations were conducted across four sites, using 40 × 40 m plots situated in ungrazed habitat with one edge facing grazed habitat. We recorded the proportion of butterflies that crossed the edge into grazed habitat compared to interior edges and the proportions that returned. By dividing each plot into 16 subplots, we quantified small-scale habitat preferences based on flight trajectories. In total, we followed 208 individuals. Results showed that butterflies were significantly less likely to cross edges into grazed areas, but there was no significant difference in return behaviour. Utilization of subplots increased with increasing abundance of the host plant (Succisa pratensis).Implications for insect conservation: This study underscores the harmful effects of intense grazing on yet another aspect (flight behaviour) of the ecology of the marsh fritillary. These findings highlight the importance of maintaining ungrazed, well-connected grasslands to conserve the marsh fritillary. [ABSTRACT FROM AUTHOR]

Viral infections are characterized by dispersal from an initial site to secondary locations within the host. How the resultant spatial heterogeneity shapes within-host genetic diversity and viral evolutionary pathways is poorly understood. Here, we show that virus dispersal within and between the nasal cavity and trachea maintains diversity and is therefore conducive to adaptive evolution, whereas dispersal to the lungs gives rise to population heterogeneity. We infected ferrets either intranasally or by aerosol with a barcoded influenza A/California/07/2009 (H1N1) virus. At 1, 2, or 4 days postinfection, dispersal was assessed by collecting 52 samples from throughout the respiratory tract of each animal. Irrespective of inoculation route, barcode compositions across the nasal turbinates and trachea were similar and highly diverse, revealing little constraint on the establishment of infection in the nasal cavity and descent through the trachea. Conversely, infection of the lungs produced genetically distinct viral populations. Lung populations were pauci-clonal, suggesting that each seeded location received relatively few viral genotypes. While aerosol inoculation gave distinct populations at every lung site sampled, within-host dispersal after intranasal inoculation produced larger patches, indicative of local expansion following seeding of the lungs. Throughout the respiratory tract, barcode diversity declined over time, but new diversity was generated through mutation. De novo variants were often unique to a given location, indicating that localized replication following dispersal resulted in population divergence. In summary, dispersal within the respiratory tract operates differently between regions and contributes to the potential for viral evolution to proceed independently in multiple within-host subpopulations. [ABSTRACT FROM AUTHOR]

An SIRS model is developed to account for precautionary measures and immunity loss. The existence and stability of equilibria are studied. It is shown that precautionary measures can induce Hopf bifurcations leading to the occurrence of cyclical behavior. The model is then extended to a two-patch scenario to explore how disease spread patterns are influenced by dispersal (travel). Theoretical analyses establish the stability of the disease-free equilibrium, the basic reproduction number, and thresholds related to travel rates. The persistence of the system, as well as the existence of boundary and endemic equilibria, are also discussed. Using Hopf bifurcation theory, we further examine the interaction between nonlinear incidence functions, travel rates, and precaution delay effects in shaping the stability of the endemic equilibrium. The findings reveal a strong connection between reduced infection rates due to precaution and the emergence of Hopf bifurcations, emphasizing the importance of timely and accurate disease information in curbing the spread of diseases. Additionally, the study highlights the significant impact of different infection force functions on equilibrium stability, underscoring the critical role of precautionary measures in disease transmission mechanisms. The results also show the diverse effects of travel rates on disease spread, suggesting that restricting travel may not always lead to favorable outcomes. This underscores the necessity for governments to consider multiple factors comprehensively in their efforts to prevent and control diseases. [ABSTRACT FROM AUTHOR]

The movement of species to new geographical areas has been proposed to be crucial for speciation. As such, dispersal has been regarded as a likely explanation for the variation in species richness among clades. The Emberizoidea are a highly diverse Oscine bird clade native to the New World that has been characterized for their ubiquitous distribution both ecologically and geographically, making this group ideal to test how biogeographical dispersal could promote speciation. To do so, we relate dispersal rates with speciation rates of Emberizoidea families using a combination of bioregionalization analysis, ancestral area reconstruction and speciation rate estimation methods. We found that the Emberizoidea superfamily likely arose from a widespread ancestor distributed over the New World, with its range evolution being primarily driven by range contraction and the main cladogenetic events for the clade occurring within bioregions. Moreover, we demonstrate that dispersal rates between bioregions showed no relationship with speciation rates, suggesting that the movement to new geographical spaces is not a driver of speciation in this group. Instead, cladogenetic events within individual bioregions promoted by range stability prove to be an important driver for speciation at broad spatial scales for Emberizoidea families. [ABSTRACT FROM AUTHOR]

The two main extensions of rain forest in South America are the Amazon (Amazônia) and the Atlantic rain forest (Mata Atlântica), which are separated by a wide 'dry diagonal' of seasonal vegetation. We used the species-rich tree genus Inga to test if Amazônia—Mata Atlântica dispersals have been clustered during specific time periods corresponding to past, humid climates. We performed hybrid capture DNA sequencing of 810 nuclear loci for 453 accessions representing 164 species that included 62% of Mata Atlântica species and estimated a dated phylogeny for all accessions using maximum likelihood, and a species-level tree using coalescent methods. There have been 16–20 dispersal events to the Mata Atlântica from Amazônia with only one or two dispersals in the reverse direction. These events have occurred over the evolutionary history of Inga, with no evidence for temporal clustering, and model comparisons of alternative biogeographic histories and null simulations showing the timing of dispersal events matches a random expectation. Time-specific biogeographic corridors are not required to explain dispersal between Amazônia and the Mata Atlântica for rain forest trees such as Inga, which are likely to have used a dendritic net of gallery forests to cross the dry diagonal. [ABSTRACT FROM AUTHOR]

Background: Estimates of tick abundance and distribution are used to determine the risk of tick-host contact. Tick surveys provide estimates of distributions and relative abundance for species that remain stationary and wait for passing hosts (i.e. questing), but measures of tick populations may be less reliable for species that actively move in search of a host, such as Amblyomma americanum, the lone star tick (LST). Risk estimates for contact with adult LST require knowledge of the tick's spatial and temporal activity. Understanding the movement and the temporal patterns of host-seeking behavior will enhance risk assessment for LST. Methods: Using CO2-baited traps over a 2-year period, we collected wild adult LST in Oklahoma. We used mark-recapture techniques to determine the distance ticks will travel, the proportion of the tick population that is detectable over time, and the relationship between tick abundance and the number of ticks detected in the field. Using video tracking software, we measured the distance traveled and activity time in the laboratory. Results: In 24 h, LST travel up to 9 (mean = 3.2, SD = 3.6) m in the field and 36 (mean = 70.4, SD = 81.0) m in the laboratory. Marked LST were detectable in the environment for up to 14 days after release. We found that the number of recaptured ticks significantly increased with the relative abundance of ticks released, and at a minimum abundance (N = 1 tick released) LST were detectable 33.3% of the time. Across all experiments, fewer than half of marked ticks were recovered and at most 28.4% of ticks were detected with CO2-baited traps at any given time. Conclusions: Our results show that LST actively move through the environment and pose a risk for host contact at distances of tens of meters. Ticks are detectable for several weeks, but only a fraction of them are detectable at any time. Larger numbers of ticks are detected as their population size increases, but even at very low numbers, LST are recovered with CO2 baiting. These spatial and temporal aspects of LST behavior should be considered when building predictive risk models of LST-host contact. [ABSTRACT FROM AUTHOR]

Background: Many animals must adapt their movements to different conditions encountered during different life phases, such as when exploring extraterritorial areas for dispersal, foraging or breeding. To better understand how animals move in different movement phases, we asked whether movement patterns differ between one way directed movements, such as during the transient phase of dispersal or two way exploratory-like movements such as during extraterritorial excursions or stationary movements. Methods: We GPS collared red foxes in a rural area in southern Germany between 2020 and 2023. Using a random forest model, we analyzed different movement parameters, habitat features—for example landclasses and distances to linear structures—and time variables (season and time of day) within red fox exploratory, transient and stationary movement phases to characterize phase specific movement patterns and to investigate the influence of different variables on classifying the movement phases. Results: According to the classification model, the movement patterns in the different phases were characterized most strongly by the variables persistence velocity, season, step length and distance to linear structures. In extraterritorial areas, red foxes either moved straight with high persistence velocity, close to anthropogenic linear structures during transient movements, or more tortuously containing a higher variance in turning angles and a decrease in persistence velocity during exploratory-like movements. Transient movements mainly took place during autumn, whereas exploratory-like movements were mainly conducted during winter and spring. Conclusion: Movement patterns of red foxes differ between transient, exploratory and stationary phases, reflecting displacement, searching and resident movement strategies. Our results signify the importance of the combined effect of using movement, habitat and time variables together in analyzing movement phases. High movement variability may allow red foxes to navigate in extraterritorial areas efficiently and to adapt to different environmental and behavioral conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Freshwater ecosystems are among the most threatened globally. Understanding how environmental variables influence the gene flow of freshwater species can help identify landscape features requiring conservation management. We used landscape genetic resistance modelling to assess the influence of climate, topography and vegetation cover on genetic structure and gene flow in platypus (Ornithorhynchus anatinus) in an urban region of south‐east Queensland, Australia. Thirty DNA samples were genotyped using the DArTseq platform, and data were filtered to produce a panel of 5478 neutral single nucleotide polymorphism (SNP) markers. We used fastSTRUCTURE, partial redundancy analysis and maximum likelihood analyses to understand platypus genetic structure and landscape influences on gene flow. Between one and three genetic clusters were detected using fastSTRUCTURE. Partial redundancy analysis identified Topographic Wetness Index and antecedent rainfall as driving genetic differentiation between samples. A maximum likelihood population effects model suggested gene flow was spatially structured by Normalised Difference Vegetation Index at a fine scale (100 m) and antecedent rainfall at a landscape scale (1 km). Thus, less vegetated areas appear to restrict the gene flow of platypus in urban systems. Rainfall, vegetation cover and topographic wetness are also important for maintaining platypus gene flow across landscapes. Our research recommends conservation management through restoration of water flow and riverine vegetation to help maintain platypus connectivity and increase gene flow among populations. [ABSTRACT FROM AUTHOR]

Immigration and emigration are key demographic processes of animal population dynamics. However, we have limited knowledge on how fine-scale movement varies over space and time. We developed a Bayesian integrated population model using individual mark-recapture and count data to characterize fine-scale movement of stream fish at 20-m resolution in a 740-m study area every two months for 28 months. Our study targeted small-bodied fish, for which imperfect capture was accounted for (bluehead chub Nocomis leptocephalus, creek chub Semotilus atromaculatus and mottled sculpin Cottus bairdii). Based on data from 2021 individuals across all species, we found that proportions of immigrants in 20-m sections averaged 30–42% among the study species, but they varied over space and time. Creek chub immigrants increased during warmer intervals when individuals grew more and transitioned between body size classes, suggesting that immigration was due to ontogenetic habitat shifts. There was a weak pattern across the species that individuals were more likely to leave 20-m sections when flow was higher. Water-column species (bluehead chub and creek chub) were more likely to immigrate into and stay in deeper sections with more pool area. Across all species and occasions, number of immigrants to stream sections did not decrease with number of individuals that survived and stayed in the same sections. Thus, the habitat did not appear saturated, and our data provided no evidence that intra-specific interactions affected fine-scale movement at our fish densities. In conclusion, high turnover rates characterized fish movement among stream sections and their variation was associated with temporal and spatial shifts in abiotic conditions. [ABSTRACT FROM AUTHOR]

Species ranges are dynamic, experiencing expansions, contractions or shifts in response to habitat changes driven by extrinsic factors such as climate change or human activities. While existing research examines the genetic consequences of spatial processes, few studies integrate species‐specific traits to analyse how habitat changes affect co‐existing species. In this study, we address this gap by investigating how genetic diversity patterns vary among species with different traits (such as generation length, population density and dispersal) experiencing similar habitat changes. Using spatial simulations and a simpler panmictic population model, we investigate the temporal genetic diversity in refugium populations undergoing range expansion of their habitat, followed by stationary and contraction periods. By varying habitat contraction speed and species traits, we identified three distinct temporal dynamics of genetic diversity during contraction: (i) a decrease in genetic diversity, (ii) an initial increase followed by a decrease and (iii) a continuous increase throughout the contraction period. We show that genetic diversity trajectories during population decline can be predicted by comparing sampled population diversity to equilibrium values expected under expanded and contracted habitat ranges. Our study also challenges the belief that high genetic diversity in a refugium population is due to a recent and rapid habitat loss. Instead, we found contrasting effects of contraction speed on genetic diversity depending on the interaction between species‐specific traits and the dynamics of habitat change. Finally, using simulated genetic data, we found that demographic histories inferred from effective population size estimates may vary across species, even when they experience similar habitat changes. [ABSTRACT FROM AUTHOR]

In this work, we study the model of a fish species growing logistically exploited by a fishing fleet in a heterogeneous environment. The environment is made up of a network of fishing patches connected by fish migrations taking place on a fast time scale. We are interested in the maximum economic yield (MEY) which corresponds to the maximum profit made by the fishing fleet. We show that the total MEY profit of the fishery made up of all the connected fishing patches can be greater than the sum of the MEY profits of isolated patches in the absence of migration. We study the general case with any number of connected patches then focus on the case of a system composed of two patches. In the latter case, we show that asymmetry in fish migration plays an important role in increasing the total profit at the MEY by connecting patches. We illustrate our results with numerical simulations allowing us to compare the MEY fishery system with connected patches compared to the system with isolated patches. [ABSTRACT FROM AUTHOR]

The open ecosystem (e.g. grasslands, prairies, shrublands) tends to be ecologically less stable than closed one (i.e. forests) and encompassess higher spatial heterogeneity in terms of environmental diversity. Such differences are expected to differentially constrain the diversity and structure of the communities that inhabit each of them, but identifying the specific processes driving contrasting biodiversity patterns between open and closed systems is challenging. In order to understand how environmental variability might structure spider assemblages, both between and within open and closed ecosystems, we implement a high throughput multiplex barcode sequencing approach to generate a dataset for 8585 specimens representing 168 species, across the open ecosystem within the Canary Islands. Combining these with spider sequences from the closed ecosystem within the same islands, we show that spider communities in the open ecosystem show higher species richness, higher beta diversity, and higher proportions of rare species but proportionately lower numbers of endemic species than communities in the closed ecosystem. We furthermore assess if environmental heterogeneity and habitat stability are the major drivers of such differences by assessing spatial genetic structuring and the influence of bioclimatic variables. Our results point to environmental heterogeneity rather than stability as a major driver of spatial patterns between open and closed ecosystems. [ABSTRACT FROM AUTHOR]

Understanding the relationship between functional traits and fragmentation is crucial for promoting biodiversity and ecosystem function. Orchid bees (Euglossini) are important pollinators in Neotropical forests, but how body size may be associated with fragmentation and its influence on community organisation remains unexplored.We systematically sampled orchid bee communities across 15 plots in a fragmented area in the Ecuadorian Amazon basin to evaluate how patch size and isolation are associated with body size and abundance. Our samples comprised large‐bodied bees (Eulaema, Euglossa and the parasitic Exaerete), with small Euglossa notably absent.The relative representation of Eulaema species of varying sizes changed across the fragmented landscape, leading to shifts in overall mean body size consistent with the prediction that larger‐bodied pollinators are better at long‐distance movement.Euglossa, the most abundant genus (67% of the total sample), was found across all patches regardless of body size. Euglossa intersecta and Euglossa orellana, the largest Euglossa in the region, were the most common species across the fragmented landscape.The abundance of male euglossines experienced a general decline with decreasing patch size and increasing isolation. However, at the species level, the abundance of some species was not affected at all. Because body size often mediates dispersal ability, thermoregulation, and resource use, we reinforce the importance of assessing body size patterns to understand changes in diversity, abundance and the composition of tropical pollinator communities in fragmented landscapes. [ABSTRACT FROM AUTHOR]

Around the world, the number of species establishing outside of their native range has and continues to increase rapidly. Some of these non‐native species are invasive and can cause negative environmental, economic, and social impacts, including declines in native biodiversity. Species can become established either through natural dispersal or with intentional or inadvertent human assistance, but the relative importance of these two modes over time has been little studied.We compiled data on 116 moth species that became established in Great Britain (GB) between 1900 and 2019. We classed each species as either an immigrant, which had colonised naturally, or an adventive, which had colonised through human assistance, and categorised species as feeding on either native or non‐native larval host plants.We found that the rate of moth species establishment has accelerated steadily, at 21% increase per decade, showing no signs of saturation. Immigrant species showed a steady rate of establishment between 1900 and 1935, followed by a significant acceleration of 11% per decade thereafter, which most closely matches the rate of immigrants that feed on native host plants. Immigrants that feed on non‐native host plants show a slower increase across the whole time period compared to all species, of 13% per decade.Adventive species show a similar rate of increase in establishment to all moth species, at a rate of 26% per decade. Adventives on non‐native host plants show a similar trend, but we find evidence for a post‐1980s increase in the rate of establishment for adventives that feed on native host plants.Our results indicate that the global case for enhanced biosecurity, around both the monitoring of natural colonisations and for the horticultural trade, remains very strong as non‐native colonisations are showing no signs of saturation with ongoing environmental and economic change. [ABSTRACT FROM AUTHOR]

European earwig, Forficula auricularia L. sensu lato (Dermaptera: Forficulidae), is a univoltine, resident, omnivorous species and a beneficial predator in pome fruit orchards. Here, three methods were used to investigate pear (Pyrus communis L., Rosaceae) orchard inoculation with European earwig for biocontrol of pear psylla, Cacopsylla pyricola (Foerster) (Hemiptera: Psyllidae), in Washington State, USA. The first method was earwig inoculation experiments. In a first experiment (2019–2020), each of three orchards had one inoculation and one control plot. In a second experiment (2020–2021), there were four inoculation and four control plots in each of the same three orchards. In both experiments, earwigs persisted during the year of inoculation, but earwigs were nearly absent the following season at two orchards that used conventional broad‐spectrum pesticides. At the third orchard, which excluded broad‐spectrum pesticides under an integrated pest management (IPM) program, earwigs became abundant in year two of the second experiment. The second method was case studies. In the first of two case studies, during 2016, 2017, 2022, and 2023, in half of the integrated orchard from above, conventional broad‐spectrum sprays were used. Earwig populations became low in the conventional half. In the second case study, earwigs became abundant after inoculation of an integrated orchard by the grower. Earwigs spread to the edge of the orchard in year two and spilled into a neighboring orchard in years three and four. The third method was an observational study of 36 pear orchards over 5 years. Earwigs were rarely found in conventionally sprayed orchards, and earwigs increased each additional year integrated management was used. The findings suggest conventional pear spray programs in Washington nearly eradicate earwigs, but populations can recover under integrated management with natural dispersal from refuges or with inoculative releases. [ABSTRACT FROM AUTHOR]

BACKGROUND: Many studies have demonstrated that tephritid fruit fly larvae are highly susceptible to entomopathogenic nematodes (EPNs) and may become infected as they enter the soil to pupate. However, the susceptibility of adult tephritids and their suitability as EPN targets have been less studied. We performed laboratory assays with 12 Australian EPN strains of Heterorhabditis bacteriophora, Heterorhabditis indica and Heterorhabditis zealandica in adults of the Queensland fruit fly, Bactrocera tryoni. Infective juveniles were delivered in a yeast hydrolysate solution that is attractive to flies. We also measured the flight ability of adults up to 3 days after treatment. RESULT: Flies that consumed the EPN‐yeast preparation experienced 72.8–84% mortality. Between 33.5% and 46.2% of EPN‐treated adults were still able to fly before death following treatment, mostly within the first day, thereby contributing to EPN dispersal. Another 31.9–39.9% of EPN‐treated flies that were unable to fly died as a result of EPN treatment. Overall, >65% of flies that died following EPN treatment had visible signs of infection and EPN reproduction. CONCLUSION: Our study is foundational to the development of attract‐and‐kill and autodissemination approaches involving EPNs in fruit fly control. Furthermore, H. indica and H. zealandica strains showed the highest potential as biocontrol agents against adult flies. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Typhlodromus (Anthoseius) recki feeds on pest mites on tomato plants and its introduction into crops via companion plants, Mentha suaveolens and Phlomis fruticosa, has been recently investigated. This study aims at assessing the predator arrestment behavior, through lab choice tests to determine the effects of (i) prey (Aculops lycopersici and Tetranychus urticae) vs Typha angustifolia pollen deposited on companion plant or Solanum nigrum, (ii) T. urticae vs A. lycopersici on S. nigrum and (ii) M. suaveolens vs P. fruticosa using pollen as food source. The predator position, the number of eggs laid and the number of T. urticae eggs consumed were assessed during 4 days. The predator was more observed on leaf discs with A. lycopersici vs pollen when the pollen was deposited on S. nigrum and M. suaveolens, but was more found on leaf discs with pollen on P. fruticosa. It was equally found on leaf discs with T. urticae vs pollen for all the plants tested. No difference in predator arrestment behavior was noted between A. lycopersici and T. urticae, but a higher proportion was observed on leaf discs with A. lycopersici at the beginning of the experiment than at the end. Finally, the predator was more observed on leaf discs of P. fruticosa than of M. suaveolens. The highest fecundity was observed in systems with pollen and A. lycopersci + pollen, and the lowest with T. urticae + pollen; T. urticae consumption was not different with pollen or A. lycopersici. The predator less arrested on pollen vs A. lycopersici that provides a high fecundity; however, surprisingly it was more attracted to pollen vs a prey T. urticae, questioning the cues perceived by T. (A.) recki. The strong preference for P. fruticosa without prey vs S. nigrum with prey or M. suaveolens with pollen, suggests for the second time for Phytoseiidae, direct effects of plant (may be via odors) and questions the ecological advantages of such a behavior. For practical issues, M. suaveolens would be a better bank plant than P. fruticosa; an arrestment on patches of A. lycopersici within tomato plant is expected even if pollen is present and in case of T. urticae infestation a low dispersal to this prey will probably occur, questioning the interest to use T. (A.) recki in combination with other Phytoseiidae species, specialized in T. urticae predation, as Phytoseiulus persimilis. [ABSTRACT FROM AUTHOR]

Information on the life histories of male macaques after leaving their natal troops is limited. A solitary male Japanese macaque (Macaca fuscata), estimated to be 5 years old, appeared in the urban area of Ishinomaki City, Miyagi Prefecture, northern Japan, where no troops are distributed, in May 2023. Because the animal was habituated to and fed frequently on garden crops, it likely came from the western part of the prefecture, where multiple crop-feeding troops are distributed. The male stayed in the hilly area in the central part of the city until June and then moved north in July. The male moved south to the tip of the Oshika Peninsula and returned to the urban area in August, after which the location of the male was unknown. This study demonstrated that (1) male macaques can move > 40 km from their natal troop, (2) the daily travel distance (average: 0.9 km) of solitary males was similar to that of troop animals, whereas the home-range size of solitary males was much bigger than that for single animals, and (3) the home-range location of solitary males changes quickly. These results implied that solitary males in novel environments prioritize finding new troops to join. Our study sheds light on aspects of male life history after dispersal. [ABSTRACT FROM AUTHOR]

Succession is one of the most extensively studied ecological phenomena, yet debates persist about the importance of dispersal and external factors in driving this process. We aimed to quantify the influence of these factors by investigating how wing‐related traits evolve across succession of blowfly (Diptera: Calliphoridae) communities in South Brazil. Rat carrion was placed in both forest and grassland habitats, and the associated blowfly communities were documented throughout the decomposition process. Using morphometric analysis, we measured wing and thorax traits and assessed trait changes over succession through mixed models. Our findings revealed that carrion succession follows distinct trajectories in forest and grassland environments. Specifically, we observed that Calliphora lopesi predominantly visited carcasses during the final phase of decomposition, resulting in significant differences in species composition and wing size between habitats. In forests, wing size increased toward the later stages of succession, whereas an opposite trend was observed in grasslands. Notably, these trait patterns were only evident at the species level, indicating that intraspecific trait variation is irrelevant. Stronger dispersers tend to arrive during the later stages of succession, suggesting that dispersal has a negligible role in shaping successional dynamics. Instead, environmental differences between habitats drive trait patterns throughout succession. Our results suggest that community composition in ephemeral resources is governed by deterministic processes and that successional stages can be predicted based on blowfly wing traits. Specifically, the presence of the large‐winged C. lopesi indicates late decay, while the small‐winged Chrysomia albiceps and Lucilia eximia are indicative of early decay. [ABSTRACT FROM AUTHOR]