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While there is a global trend in kelp forests decline, sub-Antarctic Beagle Channel kelp ecosystems are among the most stable and extensive in the world, acting as a climatic refuge, indicating its high conservation value. Nevertheless, these coastal ecosystems are increasingly exposed to anthropogenic drivers that can affect kelp strategies and promote their replacement by turf. This study evaluated the urban impact of a coastal city in the Beagle Channel (Ushuaia, 54° S 68° W) on giant kelp (Macrocystis pyrifera) population dynamics. Seasonal samplings were conducted between 2020 and 2023 in two contrasting sites: an urban site directly exposed to Ushuaia pressures and a non-urban site. Our results indicate a reduction in both kelp adult density and kelp recruitment at the urban site. Here, high sediment inputs were the main factor affecting kelp recruitment, but higher density of potential grazers, and changes in the understory macroalgae assemblage were further observed. Morpho-functional composition and sediment trapped within the macroalgae suggest the prevalence of turf-forming algae dominating the urban site's understory assemblage. If neglected, the decline in kelp recruitment rates and the replacement of the forest by turf could eventually lead to a local loss of this urban-influenced sub-Antarctic kelp forest. [ABSTRACT FROM AUTHOR]

The olive psyllid, Euphyllura olivina Costa (Hemiptera: Psyllidae), causes considerable damage in the olive groves of the Mediterranean area, resulting in significant loss in olive oil production. The present work aims to gain a first overview on the genetic diversity of this species in Tunisia by analyzing patterns of genetic variability in the mitochondrial cytochrome oxidase subunit 1 (COI) and the nuclear Internal Transcribed Spacer marker (ITS). Our analyses revealed low genetic differentiation among the studied populations, with low nucleotide and haplotype diversity. These results are associated with frequent rare variants and high gene flow exchange, suggesting recent colonization followed by population expansion across the invaded range. We cannot exclude the possibility that the low genetic diversity results in part from a reduction in the population size associated with poor performance under the current climatic conditions. Future investigations could benefit from the inclusion of additional genetic markers, including microsatellites, or population genomic approaches, to trace more accurately the demographic history and genetic differentiation of the olive psyllid. [ABSTRACT FROM AUTHOR]

This study investigates the qualitative properties and numerical dynamics of a stochastic epidemiological model incorporating unreported cases with a general contact susceptible function, shedding light on the intricate dynamics of infectious diseases such as COVID-19. In the qualitative analysis, we rigorously examine the mathematical properties of the model, including the existence and positivity of solutions, and identify a critical threshold parameter, R s , pivotal in determining the long-term behavior of the system. Notably, our analysis reveals that the stochastic noise significantly influences the dynamics, leading to distinct outcomes: if R s exceeds unity, solutions converge exponentially to a unique invariant probability distribution, whereas values below one result in the extinction of infectious diseases at an exponential rate. In the numerical study, we delve into comprehensive simulations to validate our theoretical findings and explore the behavior of the model under various scenarios. Synthetic data simulations provide illustrative examples, showcasing both disease extinction and persistence phenomena. Furthermore, we investigate the impact of the susceptible contact function, g(S), on disease dynamics, and propose a selection method for optimizing this function based on real-world COVID-19 data from the UK. By integrating rigorous mathematical analysis with empirical data-driven insights, our study offers valuable contributions to understanding the complex dynamics of infectious diseases. [ABSTRACT FROM AUTHOR]

The Southern Ocean microbial ecosystem, with its pronounced seasonal shifts, is vulnerable to the impacts of climate change. Since viruses are key modulators of microbial abundance, diversity, and evolution, we need a better understanding of the effects of seasonality on the viruses in this region. Our comprehensive exploration of DNA viral diversity in the Southern Ocean reveals a unique and largely uncharted viral landscape, of which 75% was previously unidentified in other oceanic areas. We uncover novel viral taxa at high taxonomic ranks, expanding our understanding of crassphage, polinton-like virus, and virophage diversity. Nucleocytoviricota viruses represent an abundant and diverse group of Antarctic viruses, highlighting their potential as important regulators of phytoplankton population dynamics. Our temporal analysis reveals complex seasonal patterns in marine viral communities (bacteriophages, eukaryotic viruses) which underscores the apparent interactions with their microbial hosts, whilst deepening our understanding of their roles in the world's most sensitive and rapidly changing ecosystem. The study reveals that the Southern Ocean hosts a unique and largely underexplored DNA viral community. It explores the diversity of viral communities infecting all domains of life and their seasonality, emphasizing their role in ecosystem dynamics. [ABSTRACT FROM AUTHOR]

Influenza D virus (IDV), the cattle flu virus, is a novel multi-host RNA virus, circulating silently worldwide, with widespread seropositivity among US cattle, reaching up to 80% in some areas raising a potential threat of cattle-to-human transmission. Currently, five genetic lineages of IDV have been described, but their evolutionary dynamics have not been studied. Although IDV was first identified in 2011, our comprehensive analysis of all known IDV genomes suggests that the earliest ancestors of IDV likely to have evolved towards the end of the 20th century and D/OK lineage appears to have emerged in 2005. We confirmed a significantly higher substitution rate in IDV than in Influenza C virus, which is consistent with their global distribution and multi-host tropism. We identified multiple sub-populations within the D/OK lineage, highlighting extensive diversification and dissemination. Other findings are evidence for potential reassortment among IDV strains in the USA and transboundary circulation of IDV in Europe with introductions into Danish cattle, some of which potentially originated from France. IDV, an emerging virus with a higher rate of evolution and uncontrolled circulation, could facilitate its adaptation to humans. Our findings underscore the importance of targeted surveillance for IDV in humans and at-risk animal populations. Evolutionary dynamics and population stratification analysis of whole genomes of the cattle flu Influenza D virus reveal its high evolution rate, extensive diversification and global dissemination, stressing the need for targeted surveillance. [ABSTRACT FROM AUTHOR]

The article presents the results of assessing the dynamics of the age at marriage of the reproductive part of the population of the south of Central Russia, which acts as one of the factors in the dynamics of the genetic structure of subsequent generations. Over 130 years (from 1890–1910 to 2016–2018), there was an increase in the age of marriage for men (+5.11 years, from 24.05 to 29.16 years) and women (+5.78 years, from 20.39 to 26.17 years), and the average difference in the age of spouses decreased by 0.66 (3.66 to 3.00 years). At the end of the 19th century, the marriage age of the urban population of the reproductive part of the population was higher than that of the rural population (especially among men). By the middle of the 20th century, the average age of marriage among the rural population increased, exceeding the city indicators, and this trend continued in subsequent generations until 2016–2018. There was a decrease in the average age difference between spouses, especially in the urban part of the population. At the end of the 19th century, the average difference in the age of spouses among urban residents was 1.4 times higher than for rural residents, and by the beginning of the 21st century, on the contrary, it was 1.4 times lower. Positive marital assortativity by age of spouses increased over the 130-year period (1.2 times), both in the city and in the village, but was more significant for residents of rural areas (except for the period 1991–1993). Changes in the average marriage age of spouses that have been occurring in recent decades are of particular significance from a medical-genetic point of view (especially the age at which women marry), since this indicator is potentially significant for determining the prevalence of a number of hereditary diseases among the population. Studying the age at marriage allows us to identify unfavorable trends and risks of potential negative changes in the structure of gene pools (and accordingly, the level of health) of subsequent generations. [ABSTRACT FROM AUTHOR]

Diplonychus indicus, a tropical, skilled predatory water bug with a global distribution, has been studied for its predatory performance. In this study, a detailed account and a thorough assessment on the population dynamics, reproductive fecundity, and the various factors, viz., effect of space size, temperature, food deprivation, aquatic vegetation, competition, and prey density influencing the predatory performance of D. indicus have been portrayed. Over the course of a year, the population dynamics of D. indicus was observed in a permanent pond located in the Kanyakumari region of Tamil Nadu, Southern India. Except for temperature, D. indicus nymphs and adults, had a positive correlation with abiotic (temperature, pH, dissolved oxygen, and rainfall) and biotic (Culex larvae) parameters. With regard to reproductive fecundity, on an average, 20 female individuals of D. indicus produced 1062 eggs, with a maximum hatching percentage of 88.3 at water temperatures of 25–26 °C, and an incubation period of 9.0 ± 0.35 days. The stadial duration of nymphs was 77.68 days, with the Ist stage being the shortest (5.2 ± 0.32 days) and the Vth stage the longest (34.22 ± 4.12). The IVth stage followed by the Vth stage had the highest rates of survival from egg to adult. The predatory performance of D. indicus nymphs evaluated based on the following factors, viz., space size, temperature, starvation, vegetation, competition, and prey density, are as follows. Maximum number of prey (Culex larvae) predated (411.20 ± 8.76) was in circular experimental glass container of 1 L volume space size; at a temperature of 25 °C (11.20 ± 0.30); after 24 h of starvation (558.26 ± 2.56); in 2.0 g density of aquatic vegetation (388.16 ± 2.32); with six competitors (2484.60 ± 8.10); and at 80 prey density (28.52 ± 1.02). The current study provides a critical insight into these variables that are crucial in the predatory performance of their prey, and are successful parameters in establishing a specific predator-prey interaction. This is a useful parameter for figuring out a specific predator-prey interaction in the wild. All the above mentioned factors will affect how well D. indicus performs as a predator in the field. [ABSTRACT FROM AUTHOR]

Energy landscapes can provide intuitive depictions of population heterogeneity and dynamics. However, it is unclear whether individual cell behavior, hypothesized to be determined by initial position and noise, is faithfully recapitulated. Using the p21-/Cdk2-dependent quiescence-proliferation decision in breast cancer dormancy as a testbed, we examined single-cell dynamics on the landscape when perturbed by hypoxia, a dormancy-inducing stress. Combining trajectory-based energy landscape generation with single-cell time-lapse microscopy, we found that a combination of initial position and velocity on a p21/Cdk2 landscape, but not position alone, was required to explain the observed cell fate heterogeneity under hypoxia. This is likely due to additional cell state information such as epigenetic features and/or other species encoded in velocity but missing in instantaneous position determined by p21 and Cdk2 levels alone. Here, velocity dependence manifested as inertia: cells with higher cell cycle velocities prior to hypoxia continued progressing along the cell cycle under hypoxia, resisting the change in landscape towards cell cycle exit. Such inertial effects may markedly influence cell fate trajectories in tumors and other dynamically changing microenvironments where cell state transitions are governed by coordination across several biochemical species. [ABSTRACT FROM AUTHOR]

Habitat selection of seed-dispersing animals influences where seeds are deposited, seedling establishment, and population dynamics. In the Patagonian temperate forests there is a key mutualistic relationship between the mistletoe Tristerixcorymbosus and its seed disperser, the nocturnal arboreal marsupial Dromiciopsgliroides. In this study, we analyzed the habitat selection of D.gliroides at two different habitat scales: site selection and step selection. Also, we analyzed if the selected microsites by this marsupial are suitable for the establishment of T.corymbosus. We captured 24 individuals in Parque Municipal Llao Llao (San Carlos de Bariloche, Argentina) during the austral summer of 2014 and 2015. The captured individuals were equipped with a spool and line device to register habitat use: substrate, vegetation cover, diameter and angle of branches. We used a conditional hierarchical logistic Bayesian regression at each habitat scale. We found that, at the site scale, D.gliroides selected habitats with more shrub cover and, at the step scale, D.gliroides selected more T.corymbosus host species. Besides, our results show that D.gliroides selected branches with intermediated size (4–10 cm) and also horizontal branches. The relationship between the selected sites and those where it deposits the T.corymbosus seeds suggests that the marsupial dispersing the seeds to suitable hosts and branch sizes. Therefore, the behavior of D.gliroides would be favoring the regeneration of T.corymbosus. [ABSTRACT FROM AUTHOR]

Transitional areas provide many benefits and advantages for several species according to shifts in environmental conditions. Because mangrove crabs (U. cordatus) seem to benefit from the ecotone between mangrove (M) and estuarine várzea (V) forests on Marajó Island, eastern Amazon coast, we investigated whether crab population structure varies in response to shifts in vegetation and fishing pressures. Generalized linear models revealed that crabs are larger and heavier at Furo do Saco (FS), where estuarine várzea trees dominate the landscape, and have higher density and biomass at Praia do Goiabal (PG), where the landscape is dominated by mangrove trees. Multivariate models also indicated that the distance between villages and crabbing sites turns transition zones into difficult access for crabbers and shelters for larger and more commercially profitable resources. The combined analysis of both biotic (crab and vegetation) and fishery variables highlighted the role of transition zones as a key environment for demographic maintenance and species conservation, guaranteeing the natural stocks and other ecological advantages for the sustainable fishery of mangrove crabs for future generations. [ABSTRACT FROM AUTHOR]

Small-sized fishes play a crucial ecological role in the dynamics of riverine systems, but their low dispersal capacity and high endemism make them highly vulnerable to environmental change. In the Neotropical region, each watershed typically supports unique populations of small-sized fishes, and in this study, we used Psalidodon paranae (Characidae) as a model to understand the relationships between its population patterns (including age, growth, and reproductive biology) and environmental characteristics. Standardised monthly sampling of P. paranae was carried out at ten sampling sites from June 2010 to May 2011, and environmental variables (including water quality and river characteristics) were measured to characterise these sites. Multivariate techniques and generalised linear models were used to analyse the longitudinal distribution of P. paranae, which was significantly influenced by river depth and width, and suspended solid concentrations. Linear and non-linear models were used to describe the length–weight relationship (resulting in an isometric pattern, b = 3.0256) and the growth patterns (L∞ = 21.8 cm, k = 0.51 year−1, and Φ′ = 2.3989). The analysis of gonadal maturity was combined with somatic and reproductive indices, allowing the identification of spawning periods (occurring mainly during the austral summer) and areas (sites with headwater characteristics). Our results indicate that P. paranae has a good adaptability to the different environmental conditions, and this first assessment of age and growth parameters constitutes a reference for monitoring and further evaluation of long-term changes. [ABSTRACT FROM AUTHOR]

This study explores sustainable agricultural practices by examining the role of organic materials in enhancing native predatory mites for controlling spider mites in apple orchards. Developing techniques to conserve indigenous natural enemies is vital for sustainable agricultural production. Phytoseiid mites can control spider mites, which are among the most significant pests in apple production. To conserve phytoseiid mite populations, it is important to identify alternative prey and to determine their role in phytoseiid mite proliferation. We demonstrated that the concurrent use of specific organic fertilizers and coconut husks can increase prey Tyrophagus mites, thereby enhancing phytoseiid mite density. Our research was conducted using sticky traps at the Miyagi Prefectural Agriculture and Horticulture Research Center in Japan. The occurrence of Tyrophagus mites was significantly correlated with the occurrence of phytoseiid mites in 2 years. In laboratory experiments, the use of organic fertilizers increased the density of Tyrophagus mites by 83 × within 4 weeks. Several species of phytoseiid mites were able to lay between 0.25 and 1.03 eggs per day per female by preying on Tyrophagus larvae. A 2-year field survey revealed that the use of organic fertilizers more than doubled the density of phytoseiid mites on apple leaves, likely through promoting Tyrophagus mite proliferation on the ground. These results highlight the potential of organic fertilizers not only to enhance soil nutrients, but also to boost phytoseiid mite populations, thereby contributing to more sustainable apple production. [ABSTRACT FROM AUTHOR]

Colonization of new habitats is a key event in forming current distributions in organisms. It has been speculated that freshwater fish eggs can be dispersed passively by attaching to or egestion from waterbirds that arrive in wetland habitats. Recent research showed that some freshwater fish eggs could be excreted alive from birds and then successfully hatch, but scientific evidence of bird-mediated fish dispersal is still limited to endozoochory (internal transport through a bird’s digestive tract). Here, we experimentally suggest the dispersal potential in another way or epizoochory (external dispersal by attaching to waterbirds), using medaka Oryzias latipes, which spawns on aquatic plants. Our field experiment showed that waterbirds could carry artificial aquatic plants among waterbodies. Medaka eggs attached to aquatic plants could survive in the air for up to 18 h with a median lethal period of 16.3 h. Those two findings raise the possibility of the epizoochory of medaka in nature. [ABSTRACT FROM AUTHOR]

In the face of accelerating urbanization, Urban Green Spaces (UGS) have become vital for sustaining urban ecosystems and the health and well-being of urban residents. This study offers a comprehensive analysis of the growth rate of urban green space (GRUGS) across various regions in China over a two-decade period, highlighting the interplay between urban development, population dynamics, and ecological sustainability. The research meticulously examines the impacts of urban built-up area expansion, population growth, and air pollution on GRUGS. It categorizes 291 Chinese cities into 15 urban agglomerations and utilizes data on urban built-up areas, population, and PM2.5 levels from 2000 to 2020. The findings reveal a mixed picture: while some regions demonstrate a robust commitment to integrating green spaces within urban growth, evident in high GRUGS values, others struggle to preserve green spaces amidst rapid urban expansion and population surges. This study underscores the necessity of tailored urban planning strategies that are region-specific and the ongoing need for innovation in urban development to achieve ecological sustainability. The insights garnered are invaluable for policymakers and urban planners, stressing the indispensable role of green spaces in enhancing urban life quality and securing sustainable urban environments. [ABSTRACT FROM AUTHOR]

Thalamic brain areas play an important role in adaptive behaviors. Nevertheless, the population dynamics of thalamic relays during learning across sensory modalities remain unknown. Using a cross-modal sensory reward-associative learning paradigm combined with deep brain two-photon calcium imaging of large populations of auditory thalamus (medial geniculate body, MGB) neurons in male mice, we identified that MGB neurons are biased towards reward predictors independent of modality. Additionally, functional classes of MGB neurons aligned with distinct task periods and behavioral outcomes, both dependent and independent of sensory modality. During non-sensory delay periods, MGB ensembles developed coherent neuronal representation as well as distinct co-activity network states reflecting predicted task outcome. These results demonstrate flexible cross-modal ensemble coding in auditory thalamus during adaptive learning and highlight its importance in brain-wide cross-modal computations during complex behavior. The computational role of individual sensory thalamic nuclei in flexible encoding during adaptive behaviors is not fully understood. Here authors, using longitudinal deep brain two-photon calcium imaging, show that changes in mouse auditory thalamus single cell and neuronal population dynamics are predictive of task outcome in cross-modal associative learning. [ABSTRACT FROM AUTHOR]

Traditional assays for counting bacteriophages and their lysogens are labor-intensive and perturbative to the host cells. Here, we present a high-throughput infection method in a microplate reader, where the growth dynamics of the infected culture is measured using the optical density (OD). We find that the OD at which the culture lyses scales linearly with the logarithm of the initial phage concentration, providing a way of measuring phage numbers over nine orders of magnitude and down to single-phage sensitivity. Interpreting the measured dynamics using a mathematical model allows us to infer the phage growth rate, which is a function of the phage-cell encounter rate, latent period, and burst size. Adding antibiotic selection provides the ability to measure the rate of host lysogenization. Using this method, we found that when E. coli growth slows down, the lytic growth rate of lambda phages decreases, and the propensity for lysogeny increases, demonstrating how host physiology influences the viral developmental program. Traditional assays for counting bacteriophages and their lysogens are labor-intensive and perturbative to the host cells. Here, the authors present a high-throughput method that can be used to estimate the number of phages in a sample, by measuring growth dynamics of the infected culture in a microplate reader. [ABSTRACT FROM AUTHOR]

Rabies is a neglected disease primarily related to dog-mediated transmission to humans. Accurate dog demographic and dynamic data are essential for effectively planning and evaluating population management strategies when designing interventions to prevent rabies. However, in Thailand, longitudinal survey data regarding dog population size are scarce. A school-based participatory research (SBPR) approach was conducted to survey owned dogs for one year in four high-risk provinces (Chiang Rai, Surin, Chonburi, and Songkhla) of Thailand, aiming to understand dog population dynamics and raise awareness about rabies. 'Pupify' mobile application was developed to collect data on dog population and observe the long-term population dynamics in this study. At the end of the data collection period, telephone interviews were conducted to gain insight into contextual perceptions and awareness regarding both animal and human rabies, as well as the social responsibility of dog owners in disease prevention and control. Among 303 high school students who registered in our study, 218 students reported at least one update of their dog information throughout the one-year period. Of 322 owned dogs from our survey, the updates of dog status over one year showed approximately 7.5 newborns per 100-dog-year, while deaths and missing dogs were 6.2 and 2.7 per 100-dog-year, respectively. The male to female ratio was approximately 1.8:1. Twenty-three students (10%) voluntarily participated and were interviewed in the qualitative study. The levels of rabies awareness and precautions among high-school students were relatively low. The high dropout rate of the survey was due to discontinuity in communication between the researcher and the students over the year. In conclusion, this study focused on using the SBPR approach via mobile application to collect data informing dog population dynamics and raising awareness regarding rabies in Thailand Other engaging platforms (e.g. Facebook, Instagram, Twitter, and other popular applications) is necessary to enhance communication and engagement, thereby sustaining and maintaining data collection. Further health education on rabies vaccination and animal-care practices via social media platforms would be highly beneficial. For sustainable disease control, engaging communities to raise awareness of rabies and increase dog owners' understanding of their responsibilities should be encouraged. [ABSTRACT FROM AUTHOR]

Freshwater mussels preserve valuable information about hydrology, climate, and population dynamics, but developing seasonal chronologies can be problematic. Using clumped isotope thermometry, we produced high-resolution reconstructions of modern and historic (~ 1900) temperatures and δ18Owater from mussel shells collected from an impounded river, the Brazos in Texas, before and after damming. We also performed high-resolution growth band analyses to investigate relationships between mussel growth rate, rainfall, and seasonal temperature. Reconstructed δ18Owater and temperature vary little between the modern (3R5) and historic shell (H3R). However, a positive relationship between reconstructed δ18Owater and growth rate in H3R indicates that aside from diminished growth in winter, precipitation and flow rate are the strongest controls on mussel growth in both modern and pre-dam times. Overall, our results demonstrate (1) the impact, both positive and negative, of environmental factors such as flow alteration and temperature on mussel growth and (2) the potential for clumped isotopes in freshwater mussels as a paleohydrology and paleoclimate proxies in terrestrial environments. [ABSTRACT FROM AUTHOR]

The rapid expansion of information technology and the intensification of population aging are two prominent features of contemporary societal development. Investigating older adults' acceptance and use of technology is key to facilitating their integration into an information-driven society. Given this context, the technology acceptance of older adults has emerged as a prioritized research topic, attracting widespread attention in the academic community. However, existing research remains fragmented and lacks a systematic framework. To address this gap, we employed bibliometric methods, utilizing the Web of Science Core Collection to conduct a comprehensive review of literature on older adults' technology acceptance from 2013 to 2023. Utilizing VOSviewer and CiteSpace for data assessment and visualization, we created knowledge mappings of research on older adults' technology acceptance. Our study employed multidimensional methods such as co-occurrence analysis, clustering, and burst analysis to: (1) reveal research dynamics, key journals, and domains in this field; (2) identify leading countries, their collaborative networks, and core research institutions and authors; (3) recognize the foundational knowledge system centered on theoretical model deepening, emerging technology applications, and research methods and evaluation, uncovering seminal literature and observing a shift from early theoretical and influential factor analyses to empirical studies focusing on individual factors and emerging technologies; (4) moreover, current research hotspots are primarily in the areas of factors influencing technology adoption, human-robot interaction experiences, mobile health management, and aging-in-place technology, highlighting the evolutionary context and quality distribution of research themes. Finally, we recommend that future research should deeply explore improvements in theoretical models, long-term usage, and user experience evaluation. Overall, this study presents a clear framework of existing research in the field of older adults' technology acceptance, providing an important reference for future theoretical exploration and innovative applications. [ABSTRACT FROM AUTHOR]

The article presents the results of assessing the dynamics of parameters of Malecot's isolation by distance model among the population of Belgorod oblast from 1978–1980 to 2016–2018. When compared with data for 1890–1910 and 1951–1953 on average for the region, an increase in the root-mean-square distances between the places of birth of spouses was established taking into account long-distance migrations (6.9 times) and without them (13.3 times), as well as effective migration pressure (1.5 times), and there was a decrease in the coefficient of linear systematic pressure (11 times) and the effective population size (1.3 times). The level of local inbreeding decreased significantly among the urban population and remained unchanged among the rural population. The most pronounced changes in the parameters of Malecot's isolation by distance model occurred in the middle to the second half of the 20th century. The differences in most indicators of Malecot's isolation by distance model between city and village, maximally expressed at the end of the 19th century, decreased over the course of generations and were practically leveled out by 2016–2018. [ABSTRACT FROM AUTHOR]

The obscure mealybug, Pseudococcus viburni, is a serious agricultural pest worldwide. The biological control in commercial fields of P. viburni relies on predators and parasitoids, in particular the generalist coccidophagous ladybird Cryptolaemus montrouzieri and the specific parasitoid Acerophagus flavidulus. However, these two natural enemies can establish an intraguild predation interaction, reducing the efficiency of biological control. Cryptolaemus montrouzieri may negatively impact the population dynamics of A. flavidulus if it feeds indifferently on healthy and parasitized mealybugs. With the aim of improving the biological control of P. viburni, in this work, we studied the feeding behavior of C. montrouzieri in the absence or presence of A. flavidulus larvae of different age within mealybugs, in laboratory conditions. Subsequently, with the data obtained, we mathematically modeled the dynamics of P. viburni to study the impact on P. viburni control of different field implementation schedules for the release of ladybird and parasitoid populations. The ladybird fed on parasitized P. viburni but reduced its consumption when they were infested by parasitoids aged of 4 days or more. Modeling results suggest that these feeding preferences of predators may have a positive impact on pest control, that releasing predators and parasitoids together is in general more effective than releasing them independently, and that releasing highly effective predators alone could be the best choice. Modeling results also provide information on different release schedules. [ABSTRACT FROM AUTHOR]

We developed a reaction–diffusion model to describe the spatio-temporal dynamics of the Japanese beetle (Popillia japonica Newman), based on adult abundance data collected by the Regional Phytosanitary Service during the monitoring activities in the infested area in Lombardy (northern Italy), from 2015 to 2021. The model simulated the abundance of the pest, with a discrete time step of one year along linear trajectories departing from an initial point of establishment. The model allowed the determination of the rate of expansion (i.e. the speed at which the leading edge of a population wave moves over time) of the pest along 13 different trajectories, ranging from 4.5 to 13.8 km/y, with a mean value of 8.2 km/y. Finally, we developed a land suitability index that summarises the effect of land use on the trajectory-specific rate of expansion of P. japonica. Specifically, the model revealed an increase in the rate of expansion of 260 m per year for each additional percentage point in the land suitability index. The model presented and the knowledge acquired in this work represent an important step forward in the comprehension of P. japonica population dynamics, and they represent important elements for the development of a decision support tool for pest risk managers to design and implement scientifically driven management actions. [ABSTRACT FROM AUTHOR]

Maximum sustainable yield reference points (MSY-RPs) are usually calculated assuming spawner-recruitment relationships (SRR) and population dynamics of the stock. However, due to the difficulty of estimating SRR, the uncertainty in MSY-RPs is often too large to be put into practice. Therefore, based on the concept of maximum–minimum yield (MMY), fishing mortality (F) that gives %SPR (spawner biomass per recruitment [SPR] at a given F relative to SPR in the absence of fishing) of 30–50% (F30-50%SPR) is often used as a proxy of FMSY (F that maximizes the long-term catch). In this study, we estimated F % SPR MMY (F expected to produce %SPR at MMY) for 30 stocks of Japanese fishery resources based on the life-history parameters of the stocks and steepness assumptions derived from meta-analysis. Our results showed that %SPRMMY ranged from 23% to 62% (excluding 86% of Scomberomorus niphonius), depending on the stock and the assumed steepness scenario. If the fish were caught under F % SPR MMY , at least 70% of the MSY could be expected in Japanese fishery resources. When compared with the %SPRMSY for the 15 stocks estimated through Japanese fishery stock assessment, %SPRMMY were similar, or often larger. %SPRMMY can be considered a precautionary value, reflecting the uncertainty of SRR. [ABSTRACT FROM AUTHOR]

Conservation decisions are often based on population models that rely on underlying assumptions made about species' demographic parameters. The Rio Grande Cooter (Pseudemys gorzugi) is a conservation-dependent riverine turtle, but our understanding of its population dynamics has been limited due to the absence of long-term surveys. We used mark-recapture data collected between 2016 and 2022 from the Black River, New Mexico, USA, to evaluate P. gorzugi somatic growth parameters. Females reached larger maximum size than males but exhibited a slower growth rate. We observed only a slight difference in maximum length and Brody growth coefficient of turtles from different locations, but the growth coefficients were overall significantly lower than any other Pseudemys species. Turtles on the Black River represent the northernmost robust population of P. gorzugi. In light of the intense human use of the river and riparian areas coupled with the impacts of climate change, it is imperative to maintain commitment to conservation efforts to resist population declines given the slow somatic growth rate of the population. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of cost optimisation of individual-based institutional incentives (reward, punishment, and hybrid) for guaranteeing a certain minimal level of cooperative behaviour in a well-mixed, finite population. In this scheme, the individuals in the population interact via cooperation dilemmas (Donation Game or Public Goods Game) in which institutional reward is carried out only if cooperation is not abundant enough (i.e., the number of cooperators is below a threshold 1 ≤ t ≤ N - 1 , where N is the population size); and similarly, institutional punishment is carried out only when defection is too abundant. We study analytically the cases t = 1 for the reward incentive under the small mutation limit assumption and two different initial states, showing that the cost function is always non-decreasing. We derive the neutral drift and strong selection limits when the intensity of selection tends to zero and infinity, respectively. We numerically investigate the problem for other values of t and for population dynamics with arbitrary mutation rates. [ABSTRACT FROM AUTHOR]

The steppe marmot (baibak) is one of the typical rodents of the Eastern European forest–steppe and steppe. In the mid-twentieth century, European populations of the species were on the verge of extinction, but then, thanks to conservation measures and reintroductions, the population of boibak and range were largely restored. This work collects and presents data on two restored marmot colonies in the forest–steppe of European Russia. The research was carried out in the Central Black Earth Nature Reserve (Streletskaya steppe, two sections) and in the Volga Forest–Steppe Nature Reserve (Ostrovtsovskaya forest–steppe, three sections). The number and age composition of marmots are described. Maps of settlements with burrows and trails of marmots have been compiled; for each burrow the coordinates and type (temporary or permanent) are indicated. The population density and the number of burrows per marmot were calculated. In total, 12 marmots live in the Streletskaya steppe: ten on the "Pasture" site and two on the "Restored Steppe" site. In the first area, seven adult and three young marmots were noted, in the second, two adult marmots. Here, the reintroduction of the boibak was not entirely successful. From 2015 to 2023 the number of marmots decreased sharply, from 38 to 12 individuals, and the area of the inhabited territory fell from 10 to 3.7 hectares. In the Ostrovtsovskaya forest–steppe, 48 marmots (eight families) were recorded, of which 40 were in the first area (six families), two were in the second area (one family), and six were in the third area (one family). Of the 48 individuals, 29 (61%) are underyearlings. The reintroduction of the bobak into the Ostrovtsovskaya forest–steppe was relatively successful: the total number of animals is comparable to the number of marmots initially released (48 and 64). [ABSTRACT FROM AUTHOR]

Hardhead catfish (Ariopsis felis) are one of two Ariidae catfishes in the northern Gulf of Mexico and are one of the most common fishes found in the coastal waters in this region. As a generalist consumer with a unique reproductive life history and limited information on long-term population dynamics in the Western Gulf of Mexico, the objectives of this study were to assess trends in Texas estuaries using long-term fishery independent and dependent data sets and to conduct habitat suitability analyses in these same estuaries for both young-of-the-year and adult hardhead catfish. Some estuaries have experienced decreasing trends in catch-per-unit-effort (CPUE) of adult hardhead catfish beginning in the mid-1990s and early 2000s, and widespread decreasing trends in adult mean length were additionally observed for central and lower coast estuaries. Compared to the CPUE of finfish in the larger community, adult hardhead catfish largely exhibited decreasing trends in their relative contribution (expressed as percentage of CPUE) across most Texas estuaries. When combined with the larger Ariidae species grouping, and compared to the relative contribution of common Sciaenids, it was generally observed that the contributions of these two species groupings were converging for many estuaries. This was primarily characterized by increasing Ariidae trends. Given the trophic role of Ariidae catfishes, they clearly have the potential to exert major trophic influence on estuarine food webs. Our study highlights the value of long-term monitoring and the study of non-gamefish species in the larger assessment of community change across time. [ABSTRACT FROM AUTHOR]

Following the introduction of the 'Boolarra' strain to Australia in the mid 1960's, Common carp (Cyprinus carpio) rapidly spread in waterways across the Murray–Darling Basin (MDB) in southern-eastern Australia. A previous study of the population expansion based upon data up to the early 2000s suggested the carp population may have reached, and was fluctuating around, the ecosystem carrying capacity. It has been widely stated in the scientific literature and media that carp comprise up to 90% of fish biomass in MDB rivers; however, this figure is largely based on sparse data collected in the 1990s and the accuracy of this estimate is uncertain. Here, we analyse three decades (1994–2023) of electrofishing data to estimate the median proportion of total fish biomass contributed by carp across > 1,400 sites in lowland rivers (< 700 m elevation) of the New South Wales (NSW) portion of the MDB. The proportion of sites with fish biomass dominated (> 90%) by carp has declined from ≈ 33% of sites in the mid-1990s to ≈ 20% of sites. The proportion of biomass comprised by carp varied depending on the scale of analysis. Across the NSW MDB, carp accounted for a median of 57% (95% CI: 42.5–70.4) of fish biomass at the site level. At the river catchment scale estimates ranged from ≈ 45–66%. In contrast, the median proportion of carp within key rivers ranged from ≈ 46–80%, suggesting that carp can dominate total fish biomass in some rivers for short time-periods. The proportion of biomass contributed by carp at the NSW MDB scale was remarkably stable across decades, suggesting that the carrying capacity of carp may have been reached. Our revised estimates of the contribution of carp to overall fish biomass can facilitate informed debate around the dominance of carp in MDB rivers and provide important information for carp management in the future. [ABSTRACT FROM AUTHOR]

Coastal habitats are some of the most imperiled due to climate change and anthropogenic activities. As such, it is important to understand population dynamics of the species that may play a role in regulating coastal systems. Diamondback terrapins in Northwest Florida have been understudied, which has resulted in a gap in our knowledge for this region. To help fill this gap, we conducted a capture-mark-recapture study in St. Joseph Bay, Florida, from 2018 to 2021. Overall, we captured 518 individuals, including 146 recaptures, and we used several modeling frameworks to estimate apparent survival, recapture probability, population entrance, and population size. Our estimates of apparent survival were relatively low, especially for adult males (0.77) and adult females (0.83), but there is a considerable amount of uncertainty around our estimates. Our models indicated that the super-population consists of 1122 individuals (971–1327 95% CI), and the population is comprised of more adult males (753; 665–866 95% CI) than adult females (102; 85–130 95% CI) and juveniles (267; 221–331 95% CI). Estimates of population entrance varied by year throughout our study duration. This study is the first to document a Malaclemys terrapin population in this region of Florida, and we recommend long-term monitoring in order to gain inferences for the management of this declining coastal species. [ABSTRACT FROM AUTHOR]

The critical community size (CCS) is the minimum closed population size in which a pathogen can persist indefinitely. Below this threshold, stochasticity eventually causes pathogen extinction. Here, we introduce a mechanism of behaviour-mediated persistence, by which the population response to the pathogen alters the CCS. We exemplify this with infection transmission and non-pharmaceutical interventions (NPIs) in a population where both individuals and government authorities restrict transmission more strongly when case numbers are higher. This results in a coupled social-ecological feedback between disease dynamics and population behaviour. In a parameter regime corresponding to a moderate population response, this feedback allows the pathogen to avoid extinction in epidemic troughs. The result is a very low CCS that allows long-term pathogen persistence. Hence, an incomplete population response represents a "sour spot" that not only ensures relatively high case incidence but also promotes long-term persistence of the pathogen by reducing the CCS. We illustrate this mechanism for parameters corresponding to severe coronavirus 2 (SARS-CoV-2). Given the worldwide prevalence of small, isolated populations, these results emphasize the need for incorporating behavioural feedback into CCS estimates. Regional elimination and global eradication programs for vaccine-preventable infections could also account for this effect. [ABSTRACT FROM AUTHOR]

We investigated the demographic changes in American communities impacted by tornadoes from 2000 to 2010, exploring the factors influencing population recovery in tornado-affected communities, considering short-term (within one year) and long-term (2–10 years) outcomes. Using logistic regression models, we analyzed seven predictor variables to identify significant contributors to population recovery, including tornado strength, community size, population trend, and state status (Sunbelt or Snowbelt). The data encompassed 516 tornado-affected communities across the conterminous United States. Our findings revealed that about 55% of the communities experienced no significant population change immediately after the tornado event. However, 44% of the communities witnessed a population decline, and only 11% fully recovered within 2–10 years. Results indicated that community size and trends were pivotal in population recovery. Communities with negative population trends, especially those with fewer than 5,000 residents, faced significant challenges regaining their pre-tornado population size within 1 year. The data did not show a significant difference in population recovery between communities in the Sunbelt and Snowbelt regions. The study highlights the importance of community-level factors in shaping population recovery dynamics following tornado events. Understanding these factors can aid community leaders and disaster managers in formulating effective strategies to retain populations and encourage rapid recovery. Although certain limitations exist due to data availability, future researchers could explore additional factors, such as post-tornado policies and socioeconomic variables, to gain comprehensive insights into post-disaster population dynamics. Our research contributes value to social science disaster research, helping communities build resilience in the face of tornado hazards. [ABSTRACT FROM AUTHOR]

Continuous-time predator–prey models admit limit cycle solutions that are vulnerable to the phenomenon of phase-sensitive tipping (P-tipping): The predator–prey system can tip to extinction following a rapid change in a key model parameter, even if the limit cycle remains a stable attractor. In this paper, we investigate the existence of P-tipping in an analogous discrete-time system: a host-parasitoid system, using the economically damaging forest tent caterpillar as our motivating example. We take the intrinsic growth rate of the consumer as our key parameter, allowing it to vary with environmental conditions in ways consistent with the predictions of global warming. We find that the discrete-time system does admit P-tipping, and that the discrete-time P-tipping phenomenon shares characteristics with the continuous-time one: Both require an Allee effect on the resource population, occur in small subsets of the phase plane, and exhibit stochastic resonance as a function of the autocorrelation in the environmental variability. In contrast, the discrete-time P-tipping phenomenon occurs when the environmental conditions switch from low to high productivity, can occur even if the magnitude of the switch is relatively small, and can occur from multiple disjoint regions in the phase plane. [ABSTRACT FROM AUTHOR]

Climate change can affect reef fish both directly (e.g., mortality, growth, fecundity) and indirectly (e.g., habitat degradation). The extent to which the effects of rising water temperature could drive changes in fish populations and if and how these effects may interact with potential management interventions remain unclear. The objective of this study was to test various hypothesized mechanisms by which sea surface temperature (SST) could affect reef fish population dynamics and explore these effects in combination with fishing effort restrictions and spatial closures. To do this, we modeled hypothesized relationships between SST and two governing parameters of the fish populations: intrinsic growth rate (r) and carrying capacity (K). We coupled these temperature-dependent fish population models with a fisheries harvest model and explored interactions between thermal effects, fishing effort level, and spatial closures. Under small closure scenarios, we found that the thermal effects models predicted substantially lower fish population biomass and harvest compared to the baseline (constant r and K) model. Under large closure scenarios, the thermal effects models more closely resembled the baseline. Generally, incorporating spatial closures mitigated some of the detrimental thermal effects on fish biomass and allowed for increased harvest under certain fishing effort levels. Whether intrinsic growth or carrying capacity most affected fish population levels also depended on the fishing effort and the spatial closure area. Overall, we described how fishing effort and spatial closures can influence the relative importance of key processes and the extent to which rising water temperatures affect fish populations and harvest. [ABSTRACT FROM AUTHOR]

Measuring infaunal population dynamics relies on destructive sampling that disturbs sediments and removes animals from their habitat. Establishing effective, non-invasive sampling methods for monitoring infaunal populations can reduce the impact of scientific sampling and facilitate efficient population assessments. Using intertidal soft-shell clams (Mya arenaria L.) in eastern Canada, we explored whether population density and size structure could be estimated from visible siphon holes. Across four sites with varying sediment characteristics and infaunal species assemblages, we predicted the presence of M. arenaria with 78–100% accuracy by visually assessing siphon holes. Smaller holes (< 7.5 mm) were more likely to be misidentified. Siphon hole count was a strong predictor of actual clam count and biomass at most sites, except the site with wet muddy sediment and high densities of other infaunal species. Siphon hole length was positively related to clam shell length and wet weight at all sites; however, relationships typically had low R2 values (< 0.35). Ultimately, visual assessments of intertidal siphon holes can be effective for estimating M. arenaria densities and size structure in some habitats. Testing the application of this method to other habitats and species is warranted. [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]

Colonization of the infant gut is an important developmental process characterized by high carriage of antimicrobial resistance genes (ARGs) and high abundances of pathobionts. The horizontal transfer of ARGs to pathogenic bacteria represents a major public health concern. However, there is still a paucity of longitudinal studies surveilling ARGs in healthy infant guts at high temporal resolution. Furthermore, we do not yet have a clear view of how temporal variation in ARG carriage relates to the dynamics of specific bacterial populations, as well as community virulence potential. Here, we performed deep shotgun metagenomic sequencing of monthly fecal samples from a cohort of 12 infants, covering the first year of life to interrogate the infant gut microbiome for ARG content. We further relate ARG dynamics to the dynamics of taxa, virulence potential, as well as the potential for ARG mobilization. We identify a core resistome dominated by efflux systems typically associated with Enterobacteriaceae. Overall ARG carriage declined over the first year of life and showed strong contemporaneous correlation with the population dynamics of Proteobacteria. Furthermore, the majority of ARGs could be further mapped to metagenome-assembled genomes (MAGs) classified to this phylum. We were able to assign a large number of ARGs to E. coli by correlating the temporal dynamics of individual genes with species dynamics, and we show that the temporal dynamics of ARGs and virulence factors are highly correlated, suggesting close taxonomic associations between these two gene classes. Finally, we identify ARGs linked with various categories of mobile genetic elements, demonstrating preferential linkage among mobility categories and resistance to different drug classes. While individual variation in ARG carriage is substantial during infancy there is a clear reduction over the first year of life. With few exceptions, ARG abundances closely track the dynamics of pathobionts and community virulence potential. These findings emphasize the potential for development of resistant pathogens in the developing infant gut, and the importance of effective surveillance in order to detect such events. [ABSTRACT FROM AUTHOR]

Responding to threats in the real world demands a sophisticated orchestration of freeze and flight behaviors dynamically modulated by the neural activity. While the medial prefrontal cortex-basolateral amygdala (mPFC-BLA) network is known to play a pivotal role in coordinating these responses, the mechanisms underlying its population dynamics remain vague. As traditional Pavlovian fear conditioning models fall short in encapsulating the breadth of natural escape behaviors, we introduce a novel dataset to bridge this gap, capturing the defensive strategies of mice against a spider robot in a natural-like environment. The adaptive escape behaviors and concurrent mPFC-BLA activity in eight mice were monitored using wireless local field potential (LFP) and video recordings, both individually and in groups. Our data offers a unique avenue to explore the neural dynamics that govern fear- and vigilance-induced threat responses in isolated and social contexts. Supplemented by detailed methodologies and validation, the dataset allows for the analysis of the transient neural oscillatory dynamics, with prospective implications for the fields of neuroscience, robotics, and artificial intelligence. [ABSTRACT FROM AUTHOR]

Across the globe, many species of insects are facing population decline. This is largely driven by anthropogenic changes to the environment, including the widespread exposure of invertebrates to endocrine disrupting chemicals (EDCs), which impair fertility. To test whether generations of Drosophila melanogaster born from parents exposed to a common dietary EDC, equol, could recover reproductive function, we quantified the reproductive capacity of the two subsequent generations. Using a novel suite of flow cytometry assays to assess sperm functionality in real time, we find that sperm function is compromised across three generations, even after non-exposed in individuals contribute to the breeding population. Though the sex ratio alters in response to EDC exposure, favouring the survival of female offspring, most lineages with ancestral EDC exposure exhibit persistent subfertility in both the male and female. Male offspring with ancestral EDC exposure present with reduced fertility and dysfunctional spermatozoa, whereby spermatozoa are metabolically stressed, lack DNA integrity and present with permanent epigenetic alterations. Across generations, male and female offspring demonstrate distinct patterns of reproductive characteristics, depending upon the specific lineage of EDC exposure. Our results illustrate how dietary EDCs present in agricultural plants could promote transgenerational subfertility and contribute to declining insect populations. [ABSTRACT FROM AUTHOR]

East African countries accounted for ~ 10% of all malaria prevalence worldwide in 2022, with an estimated 23.8 million cases and > 53,000 deaths. Despite recent increases in malaria incidence, high-resolution genome-wide analyses of Plasmodium parasite populations are sparse in Kenya, Tanzania, and Uganda. The Kenyan-Ugandan border region is a particular concern, with Uganda confirming the emergence and spread of artemisinin resistant P. falciparum parasites. To establish genomic surveillance along the Kenyan-Ugandan border and analyse P. falciparum population dynamics within East Africa, we generated whole-genome sequencing (WGS) data for 38 parasites from Bungoma, Western Kenya. These sequences were integrated into a genomic analysis of available East African isolate data (n = 599) and revealed parasite subpopulations with distinct genetic structure and diverse ancestral origins. Ancestral admixture analysis of these subpopulations alongside isolates from across Africa (n = 365) suggested potential independent ancestral populations from other major African populations. Within isolates from Western Kenya, the prevalence of biomarkers associated with chloroquine resistance (e.g. Pfcrt K76T) were significantly reduced compared to wider East African populations and a single isolate contained the PfK13 V568I variant, potentially linked to reduced susceptibility to artemisinin. Overall, our work provides baseline WGS data and analysis for future malaria genomic surveillance in the region. [ABSTRACT FROM AUTHOR]

Sorghum [Sorghum bicolor (L.) Moench] is an important cereal crop widely cultivated in tropical and semi-tropical regions of the world. It is the food source for millions of people, especially in African and Asian countries. Sorghum is infested by a number of insect pests throughout the cropping season. Panicle feeding insect pests cause huge damage to sorghum grains. The present study was carried out to evaluate the influence of panicle (earhead) compactness population build-up of panicle feeding insect pests of sorghum. Four genotypes, i.e., SSG59-3 (loose), HC308 (compact), HC136 (compact) and HJ513 (semi-compact), were selected on the basis of panicle compactness and time of emergence. The major panicle feeding insect pests observed during the crop season were sorghum midge (Stenodiplosis sorghicola), earhead bug (Calocoris angustatus), thrips (Haplothrips aculeatus), dusky cotton bug (Oxycarenus latus) and stink bug (Nezara viridula). The mean population of S. sorghicola was highest on SSG59-3, followed by HJ513, HC308, and HC136. The mean population of C. angustatus was highest on genotype HC308, followed by HC136 and HJ513. On genotype SSG 59 − 3, the population of C. angustatus was not observed. The mean highest population of H. aculeatus was observed on genotype SSG59-3, followed by HJ513 and HC308. The minimum thrips population was noticed on genotype HC136. The highest mean population of O. latus was observed on genotype HC308. N. viridula was observed only on two genotypes, i.e., HC308 and HC136. Sorghum midge and thrips preferred loose types of panicle while earhead bug, dusky cotton bug and stink bug showed their preference towards compact panicle for their growth and bild-up. Effect of abiotic factors on population build-up of these major earhed feeding insect pests was also studied. The population of panicle feeding insects is variably correlated with different abiotic factors. [ABSTRACT FROM AUTHOR]

Individual predator and prey species exhibit coupled population dynamics in simple laboratory systems and simple natural communities. It is unclear how often such pairwise coupling occurs in more complex communities, in which an individual predator species might feed on several prey species and an individual prey species might be attacked by several predators. To examine this problem, we applied multivariate autoregressive state-space (MARSS) models to 5-year time-series of monthly surveys of a predatory fish, the eastern mosquitofish (Gambusia holbrooki), and its littoral zone prey species, the least killifish (Heterandria formosa), in three locations in north Florida. The MARSS models were consistent with coupled predator–prey dynamics at two of the three locations. In one of these two locations, the estimated densities of the two species displayed classic predator–prey oscillations. In the third location, there was a positive effect of killifish density on mosquitofish density but no detectable effect of mosquitofish density on killifish density. In all three locations, increased submergent vegetation cover was associated with increased prey density but not increased predator density. Eigenvalues analyses for the joint predator–prey dynamics indicated that one of the cyclic locations had more stable dynamics than the other locations. The three different patterns demonstrate that the dynamics of a pairwise predator–prey interaction emerge not only from the characteristics of the prey and the predator, but also those of the habitat and trophic web in which the predator and prey are embedded. [ABSTRACT FROM AUTHOR]

Irruptive or boom-and-bust population dynamics, also known as 'outbreaks', are an important phenomenon that has been noted in biological invasions at least since Charles Elton's classic book was published in 1958. Community-level consequences of irruptive dynamics are poorly documented and invasive species provide excellent systems for their study. African Jewelfish (Rubricatochromis letourneuxi, "jewelfish") are omnivores that demonstrate opportunistic carnivory, first reported in Florida in the 1960s and in Everglades National Park (ENP) in 2000. Twelve years after invasion in ENP, jewelfish underwent a 25-fold increase in density in one year. By 2016, jewelfish represented 25–50% of fish biomass. Using a 43-year fish community dataset at two sites (1978–2021), and a 25-year dataset of fish and invertebrate communities from the same drainage (1996–2021), with additional spatial coverage, we quantified differences in fish and invertebrate communities during different phases of invasion. During jewelfish boom, abundant, native cyprinodontiform fishes decreased in density and drove changes in community structure as measured by similarity of relativized abundance. Density of two species declined by > 70%, while four declined by 50–62%. Following the jewelfish bust, some species recovered to pre-boom densities while others did not. Diversity of recovery times produced altered community structure that lagged for at least four years after the jewelfish population declined. Community structure is an index of ecological functions such as resilience, productivity, and species interaction webs; therefore, these results demonstrate that irruptive population dynamics can alter ecological functions of ecosystems mediated by community structure for years following that population's decline. [ABSTRACT FROM AUTHOR]

Mandothi Wetlands located in district Jhajjar of Haryana, India is about 1000 acres of farmland, serves as a crucial habitat for numerous species of winter migratory birds. From December 2021 to March 2023, fortnightly periodic visits were made to the area by using scan sampling and point-cum-line transect methods. A total of 54 winter migratory birds' species were recorded including 33 genera, 19 families, and 8 orders. Order Charadriiformes was highly diverse with the presence of 17 species in the study area. Feeding guild analysis expressed that Insectivores were the dominant ones among all guilds. As per the IUCN Red List criteria, 48 species were classified as least concern (LC) whereas, 3 species were classified as Near Threatened (NT) i.e., Ferruginous Duck Aythya nyroca, Eurasian Curlew Numenius arquata, Curlew Sandpiper Calidris ferruginea, and 3 species were classified as Vulnerable (VU) such as Eastern Imperial Eagle Aquila heliaca, Greater Spotted Eagle Clanga clanga and Common Pochard Aythya ferina globally. Study area holds a significant role in sustaining the diversity of birds and also facing various stress factors thus it needs to be conserved. [ABSTRACT FROM AUTHOR]

This article assesses the dynamics of indicators characterizing marriage and migration parameters among the population of the south of Central Russia from 1890 to 2018. In the structure of marriages over the 130-year period, there was a significant decrease (1.6–2.2 times) in the share of isolocal marriages and a significant increase in the share of heterolocal marriages (by almost 11 times), while the size of the elementary population increased from the village level to the district/region level. From 1890 to 2018 the dynamics of isolocal marriages was more pronounced among the urban population and the dynamics of heterolocal marriages was more pronounced among rural residents. Over the 130-year period positive marital assortativity by place of birth of spouses decreased by 1.5 times without significant differences in the level and dynamics of marriage selectivity by place of birth of spouses between the urban and rural populations (except for the period of 1951–1953). A strong direct correlation was established between the level of marital assortativeness and the share of marriages concluded within one region and one district (r = 0.90, p < 0.05) and a negative one, on the share of heterolocal marriages (concluded between immigrants from different regions) (r = –0.90, p < 0.05). [ABSTRACT FROM AUTHOR]

The conservation of endangered primates often relies on data on population dynamics and health obtained from individuals captured with baited traps. This could increase the risk of injury or predation by attracting competitors and predators to the baited locations. It also can lead to unforeseen interactions of ecological significance among nontarget species. We evaluated these hypotheses by monitoring visits by multiple species to capture platforms for endangered golden lion tamarins (Leontopithecus rosalia). We placed camera traps on ten platforms baited with bananas resulting in more than 1500 species records. We calculated species richness and temporal patterns of visitation overlap among lion tamarins, predators, and competitor species. We also fitted a lion tamarin group with a GPS telemetry transmitter to assess whether movements toward and visits to the platform occurred more than expected by chance. Thirteen mammals and 12 bird species visited the platforms. There was high temporal overlap, albeit with peaks at different times, with the tayra (Eira barbara)—a main predator. Introduced hybrid marmosets (Callithrix spp.) were present on the platforms in 42% of visits by lion tamarins, and we recorded fights between the two species. There was significant temporal overlap between lion tamarins and capuchin monkeys. The lion tamarin visitation rate to platforms did not differ from random locations, nor did they show significant recursive behavior. Lion tamarins were vigilant in 90% of platform visits and emitted mild alarm calls, mobbing calls, and food calls. Their vocal output increased when marmosets were on the platforms. We suggest that lion tamarins consider the platforms an attractive, albeit risky, food resource. Baited platforms attract species beyond the target species and create conditions for unintended potentially negative effects on multiple species. [ABSTRACT FROM AUTHOR]

The assembly and persistence of ecological communities can be understood as the result of the interaction and migration of species. Here we study a single community subject to migration from a species pool in which inter-specific interactions are organised according to a bipartite network. Considering the dynamics of species abundances to be governed by generalised Lotka–Volterra equations, we extend work on unipartite networks to we derive exact results for the phase diagram of this model. Focusing on antagonistic interactions, we describe factors that influence the persistence of the two guilds, locate transitions to multiple-attractor and unbounded phases, as well as identifying a region of parameter space in which consumers are essentially absent in the local community. [ABSTRACT FROM AUTHOR]

As a reintroduction progresses through the establishment, growth, and regulation phases, density-dependent mechanisms increasingly drive population dynamics. This can complicate efforts to reinforce these populations if the translocated individuals (henceforth reinforcers) are excluded, or existing residents become displaced. This is especially pertinent for islands and fenced havens, where immigration is often only possible by translocation. Conspecific associations offer insights into how these density-dependent mechanisms manifest in space and time. We investigated how movement, habitat use, and conspecific associations differed between eastern quoll (Dasyurus viverrinus) residents and reinforcers at a conservation-fenced haven. We used GPS collars to quantify distances travelled per night, home and core ranges, nocturnal (activity) and diurnal (denning) habitat use and preference, and conspecific associations over three periods: baseline (residents only, days 3–21), release (both cohorts, days 22–32), and settlement (reinforcers only, days 33–52) for ≤ 42 days post-release (depending on GPS unit longevity). Eastern quolls travelled greater mean distances per night (< 2.15 km, x̄ 1.75 km) and had larger home ranges (< 251 ha, x̄ 178 ha) during the release period. Reinforcers had larger home ranges (249 ha) and greater overlap with other collared eastern quolls (115 ha) when compared to residents (range 90 ha, overlap 46 ha). We found a significant preference for grassland habitat across all animals and periods. During the settlement period, we found a preference for nocturnal activity in greater understory and south-west facing aspects, and lower movement correlation, sociality, and den sharing between collared eastern quolls. Finally, we found lower den sharing in reinforcers (29%) compared to residents (52%), and for fawn- animals compared to dark-morphs. Our results revealed short-term movements, habitat use, and conspecific associations at a greater spatiotemporal resolution than has ever been achieved for this species. Our findings offer important insights into the importance of appropriate habitat and conspecific cueing for reintroductions, and highlight the need to monitor density-dependent mechanisms to inform adaptive management to promote positive outcomes for both initial reintroductions and reinforcements. [ABSTRACT FROM AUTHOR]

A key goal of coral restoration is to re-establish self-sustaining coral populations and ensure resilience to future stressors, which requires that genetic diversity is maximised. However, coral genetic and genotypic (clonal) diversity is variable across reef sites via success of sexual recruitment, and cryptic species diversity can complicate breeding efforts. Assessing genotypic and genetic diversity of colonies to be used in restoration is therefore critical to avoid founder, inbreeding or outbreeding effects. Considering recent efforts to upscale coral propagation on the Great Barrier Reef (GBR), we examined species, population and clonal structure of a commonly out-planted tabular Acropora species—Acropora hyacinthus (Dana, 1864). A total of 189 colonies were sampled from six reef systems throughout the northern-central GBR and genotyped using an Acropora-specific Affymetrix microarray, which resulted in 1387 variant sites that passed quality control. Cryptic species were readily resolved and all sampled A. hyacinthus colonies represented unique genotypes within sites at three reefs. At reefs that contained multi-ramet genets (clonal genotypes), the mean and maximum between-ramet distances were 0.68 and 1.99 m, respectively. Therefore, sampling colonies > 2 m apart increases the likelihood these colonies represent distinct genets. Such a sampling design therefore maximises genotypic diversity when sourcing colonies for propagation and out-planting. Based on these variant sites, we found no between-reef genetic divergence based on locality. Furthermore, through unintentional sampling of non-target tabular Acroporid species, we show how this genotyping method may be used for resolving taxonomic uncertainty as well as population dynamics. [ABSTRACT FROM AUTHOR]

The persistence and progression of Erwinia amylovora in naturally infected orchards is still not fully understood and the majority of studies have been carried out under controlled or artificial infections. A major hurdle stems from the inability to characterize the viability of the bacterium in its natural state. Most standard tests, including real-time qPCR, fail to differentiate live from dead cells, while culture dependent methods lack sensitivity. Even in orchards with recurring infections, the detection of E. amylovora is erratic. Immuno-flow cytometry (IFCM) is considered a high throughput tool in clinics and food industry but has been rarely used as diagnostic test for plant pathogens. Two pear orchards with fire blight history, located in the central part of Portugal, were selected for epidemiological monitoring between February and June, from 2019 to 2022. A total of 440 samples were tested using EPPO standard diagnostic protocols. To address the epidemiological behaviour of E. amylovora, we devised an IFCM test using specific monoclonal antibodies and viability dyes, validated in a subset of 149 samples, testing positive in routine diagnostic tests. Our IFCM test was able to differentiate live and dead E. amylovora in naturally infected samples with concentrations as low as 3.54 × 104 cell·mL−1, confirming positive results for 91% these samples, while 19.4% were considered positive by isolation, 38% using conventional PCR and 95% for real-time qPCR. Temporal analysis showed the highest number of positive samples regardless of the method employed in April, May and June, while viability values measured with IFCM were the highest in April, coinciding with the exit of dormancy and early flowering of pear trees. Integrative analysis of E. amylovora viability and population dynamics over the growing season allowed identification of distinct outbreak risks associated with these Portuguese pear orchards. [ABSTRACT FROM AUTHOR]

Time courses of neural responses underlie real-time sensory processing and perception. How these temporal dynamics change may be fundamental to how sensory systems adapt to different perceptual demands. By simultaneously recording from hundreds of neurons in mouse primary visual cortex, we examined neural population responses to visual stimuli at sub-second timescales, during different behavioural states. We discovered that during active behavioural states characterised by locomotion, single-neurons shift from transient to sustained response modes, facilitating rapid emergence of visual stimulus tuning. Differences in single-neuron response dynamics were associated with changes in temporal dynamics of neural correlations, including faster stabilisation of stimulus-evoked changes in the structure of correlations during locomotion. Using Factor Analysis, we examined temporal dynamics of latent population responses and discovered that trajectories of population activity make more direct transitions between baseline and stimulus-encoding neural states during locomotion. This could be partly explained by dampening of oscillatory dynamics present during stationary behavioural states. Functionally, changes in temporal response dynamics collectively enabled faster, more stable and more efficient encoding of new visual information during locomotion. These findings reveal a principle of how sensory systems adapt to perceptual demands, where flexible neural population dynamics govern the speed and stability of sensory encoding. Sensory systems must adapt to changing perceptual demands. Here, the authors show that changes in sub-second timescale neural population dynamics enable flexible sensory encoding during different behavioural states, in mouse visual cortex. [ABSTRACT FROM AUTHOR]