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In this work, we study the invasion dynamics of a stage-structured population located in a one-dimensional periodic lattice. With a biologically relevant hypothesis that the population diffuses in its immature stage, we derive a novel spatially heterogeneous population model with coupled local and nonlocal effects. Assuming a KPP-type structure, we obtain the existence and variational characterization of spreading speed by appealing to monotone dynamical system theories. Further, we study the dependence of the spreading speed on the dispersal rate of immature population; it turns out that there exists an optimal dispersal strategy to maximize the speed. Numerical simulations further suggest that such an optimal strategy is unique. [ABSTRACT FROM AUTHOR]

Urban habitats differ from natural environments, however some predatory species have become established in cities across the globe. The aim of our study was to compare the occurrence of the red fox and the stone marten in Warsaw during three time periods (1976–1978, 2005–2008, 2015–2021) and in different habitats. Generalized linear models were used to show factors affecting the density indices of these two species (i.e., frequency of occurrence of tracks of each species recorded during snow tracking on linear transects). The frequency of occurrence of tracks of these two species on transects increased over time and was explained by habitat type and distance from the city centre. The frequency of fox tracks was higher in more‐natural habitats located far from the city centre. In the first period (1976–1978), this species was recorded only in forests and riparian areas. In the last period (2015–2021), its tracks were recorded frequently in built‐up areas and cemeteries. From the beginning of the first period, the stone marten was recorded in a wider range of habitats than the fox and it colonized all habitat types in the subsequent periods, but a statistically significant increase was observed only for cemeteries. The frequency of occurrence of stone marten tracks was lower than that of red fox tracks in most natural and seminatural habitats (forests, parks, riparian areas). No relationship between the occurrence of the red fox and the stone marten was found. We speculate that the growth of the urban red fox numbers was driven by an increase in the national population as a result of anti‐rabies vaccinations. In turn, the stone marten, being a synanthropic species, was present in the city centre from the beginning of the study, but it now occurs in a wider range of habitats. [ABSTRACT FROM AUTHOR]

The house mouse is a commensal species that invades natural ecosystems and threatens both native rodents and ecosystems. Therefore, it is important to describe the population of Mus musculus in native ecosystems to develop effective management plans for eradicating or controlling this species. In this study, we assessed the abundance and habitat preferences of M. musculus in Reserva Nacional de Illescas (RNI) and Manglares de San Pedro de Vice (MSPV) using capture-recapture methods during 2021 and 2022. We recorded only a few captures (N = 3) of M. musculus in the RNI, whereas numerous captures and recaptures (N = 195 and N = 41, respectively) were recorded at the MSPV. Our analysis suggests that M. musculus prefers complex habitats. We discuss the implications of the presence of house mice in mangrove ecosystems and emphasize the population dynamics of this species for its control and management in legally protected areas. In conclusion, the population size of the house mouse varies among different habitats, with a preference for complex environments. [ABSTRACT FROM AUTHOR]

The scarcity of up‐to‐date data on the distribution and dynamics of the Chinese pangolin (Manis pentadactyla) presented a significant challenge in developing effective conservation strategies and implementing protective measures within China. Currently, most of China's national‐level nature reserves and administrative departments operate at the county level, thereby limiting the applicability of larger‐scale analyses and studies for these administrative entities. This study employed 11 widely used modeling techniques created within the Biomod2 framework to predict suitable habitats for the pangolin at the county scale, while examining the correlation between environmental variables and pangolin distribution. The results revealed that highly suitable habitats in Mingxi County of China encompassed only 49 km2. Within the county‐managed nature reserve, the proportion of highly suitable habitats reached as high as 52%. However, nearly half of these areas, both moderately and highly suitable habitats, remained inadequately addressed and conserved. We found nine administrative villages that necessitated prioritized conservation efforts. The study anticipated an overall expansion in suitable habitats over the ensuing two decades, with significant growth projected in the eastern regions of Xiayang and Hufang Town. This research offered a clear and applicable research paradigm for the specific administrative level at which China operates, particularly pertinent to county‐level jurisdictions with established nature reserves. [ABSTRACT FROM AUTHOR]

This paper is concerned with the propagation phenomenon of a three species predation-competition system with nonlocal dispersal and climate change effects. That is to say, there is not only competition for food, but also competitive interaction between two preys. The growth rate of each prey is nondecreasing along the $ x $-axis and shifts rightward at a speed $ s $. We mainly consider the population dynamics for three cases: (ⅰ) the predator spreads faster than the two preys, (ⅱ) the predator spreads between two preys and (ⅲ) the predator with slower speed spreads behind the two preys, including multiple layers with different speeds to achieve a complete picture. Due to lack of comparison principle in the prey-predator system and compactness of the nonlocal operator, we give some priori estimates of the solutions to obtain the persistence for three species, which depends on improving the regularity of the dispersal kernels and proposing some parameter conditions of the considered system. [ABSTRACT FROM AUTHOR]

Decades after the publication of the first population studies on Neotropical butterflies, knowledge of their population biology remains scarce in the literature. Inconspicuous groups like the nymphalid subfamily Satyrinae are often overlooked, and studies that examine the demographics of these neglected groups are paramount for a more comprehensive understanding of insect population dynamics. The present paper addresses this dearth of information by describing the population biology of three common species of Euptychiina (Nymphalidae: Satyrinae) butterflies, Hermeuptychia atalanta, Cissia eous and Malaveria affinis, in a suburban area. A 13-month mark-release-recapture study was carried out in the grass lawns of the University of Campinas, São Paulo State Southeastern Brazil. The results showed that population parameters differ among the three studied species. For example, the population of H. atalanta is about five times that of C. eous, which is four times larger than that of M. affinis. Sex ratios were male-biased in H. atalanta and C. eous, but not in M. affinis (whose sex ratio was 1:1). Hermeuptychia atalanta and C. eous had mean adult lifespans of approximately one week, with no variation between sexes. Malaveria affinis, however, had a lifespan of approximately 11 days for males and just five days for females. Age structures were similar in all three species, with no recruitment peaks detected throughout the year. Sexual dimorphism, based on wing size, was not observed in H. atalanta, but a clear pattern of dimorphism with larger females was observed for the other two species. The present study is the first to describe population parameters for Euptychiina in detail, and one of the few focusing on population biology of butterflies in suburban areas. Indeed, the present results could help to define strategies of lawn management for the campus, aiming to increase local biodiversity and consequently improve ecosystem services. [ABSTRACT FROM AUTHOR]

The specific factors that influence spatial community or population dynamics are often elusive, and even less known is the impact of tropical urban landscapes on diverse species community assemblages.To address this knowledge gap, we used a survey data set with 510 fruit‐feeding butterflies comprising 20 species across two heterogeneous habitats within a city in Nigeria. Next, we constructed generalised linear mixed models to understand the differential responses of the butterfly community to changes in environmental conditions across habitats.Butterfly species community assemblages significantly differed between the two urban habitats, with butterfly species significantly higher in the savannah woodland compared with the gallery forest due to the optimal daily temperatures of the savannah woodland. However, butterfly richness was lower in the gallery forest due to extreme environmental conditions.This study highlights that butterfly community changes in tropical urban landscapes are possibly responding to local microclimates and spatial heterogeneity across habitats.For evidence‐based conservation management of tropical butterfly biodiversity, there would be need for a long‐term, extensive and systematic insect monitoring programme for butterflies across disturbed and undisturbed fragmented habitats harbouring diverse insect species. [ABSTRACT FROM AUTHOR]

Pronghorn (Antilocapra americana), a symbol of western North America, experienced diverging population trajectories since the mid‐twentieth century, with northern populations showing signs of recovery while those in the arid Southwest have struggled to persist. We conducted a systematic literature review of papers published through August 2023 to understand 3 questions. What are the habitat conditions needed for pronghorn to persist? What management actions can be taken to foster higher quality habitat? Do these actions differ for populations in the arid Southwest compared to their northern counterparts? Although the fundamental habitat requirements for pronghorn persistence have remained constant since the early 2000s, it has become clear that precipitation is a key factor influencing pronghorn populations in the arid Southwest. The precise mechanisms by which precipitation influences pronghorn population dynamics are not yet clear, whether through the availability of free water, by affecting forage quality, or indirectly via predator‐prey dynamics. Although range‐wide forage enhancement may be impractical, providing additional free water sources could facilitate greater movement, enabling pronghorn to access more and higher quality forage and areas with lower predation risk. To clarify how pronghorn persisted for thousands of years in this harsh environment, we must gain a better understanding of their historical metapopulation and migratory behaviors in the arid Southwest. [ABSTRACT FROM AUTHOR]

Understanding the effects of exogenous and endogenous factors on species demographic rates is crucial to investigate their chances of persistence on natural ecosystems. We used a 9-year time series, based on monthly captures, to test the delayed effects of endogenous (density) and exogenous (rainfall, habitat cover/heterogeneity, fire) factors on the survival and recruitment rates of two small mammals inhabiting the Brazilian Cerrado: the semelparous, scansorial marsupial Gracilinanus agilis and the iteroparous, arboreal rodent Rhipidomys macrurus. As in most short-lived small mammals, we found negative density-dependent effects on the recruitment of both species (3 months delay), which could occur through reduced immigration or fecundity, in addition to the semelparous breeding strategy of G. agilis. Reduced habitat cover following fire events had a negative delayed effect on the survival of G. agilis (3 months after) and R. macrurus (1 year after), albeit it increased the recruitment rates (1-year lagged effect) of R. macrurus. We failed to find any effect of fire on demography of either species. Our results suggest that the irregular and non-cyclical fluctuations in R. macrurus abundance were driven by the interaction between delayed density dependence and changes in habitat quality, while the marked and repeated fluctuations in G. agilis abundance were mainly shaped by the occurrence of semelparity associated with direct density dependence. We emphasize that changes in habitat quality brought by human-made activities may have severe impacts on the dynamics and persistence of forest-dependent small mammals in the Cerrado. [ABSTRACT FROM AUTHOR]

The Black Sea steppes and particularly the steppe–field area between the Velykyi Kuyalnyk and Southern Bug rivers, delineated from the north by the valley of the Kodyma River, are a natural arena for the existence of two species of mole rats, which still inhabit fields, virgin steppe areas, ravines and river valleys. The materials of the article are the result of long-term (1989–2023) studies of the steppe biota of this territory, which has an area of 15 559 km2. The habitats of mole rats, found by characteristic molehills, do not allow species differentiation, so all mole rats are provisionally assigned to two species— Spalax leucodon (west of Tiligul) and Spalax zemni (east of Tiligul). The habitats of mole rats are distinguished by stationarity for decades, but the seasonal-stationary manifestation of burrowing activity is unstable—the main share of ‘fresh’ emissions in the fields falls on May–June and October–December. The main reserves of the species are meadow areas of river valleys and ravines, which are not subject to flooding. The highest concentration of mole rats was found in the valleys of Tylihul (from the village of Andriyevo-Ivanove down to the town of Berezivka) and Velykyi Kuyalnyk (from the town of Shiryaevo to the village of Severynivka). In the agricultural landscape, in particular in fields (winter and old ploughing), the locations of mole rats are scattered sporadically, gravitating towards river valleys. Thus, field locations on the eastern outskirts of Odesa essentially extend the Sudlymansko–Kuyalnytsia strip of the subarea to the sea coast. At the same time, the nature and activity of burrowing activities of mole rats has a pronounced stationary-biotopic dependence on the level of their food supply. Thus, the ‘chains’ of soil emissions in winter crops, on old ploughing and rolled up crops of spring crops are always long (36–45 m) and combine 28–60 molehills. Similar ‘chains’ in the natural habitats of river valleys, ravines, along the edges of forest belts and near roads are always short (6–11 m) and each time are represented by only 3–5 molehills. Preservation of the main reserves in river valleys from the threat of further anthropogenic transformation is the main means of protecting mole rats within the Southern Steppe.

The population abundance of birds is an important way to gauge the sustainability and health of the environment. However, several factors influence their distribution and density in different habitats. This paper aims to provide a comprehensive and updated outlook on bird population dynamics in Europe in the past 40 years. With the use of Generalized Additive Mixed Models (GAMMs), we analyzed the data available from the Pan-European Common Bird Monitoring Scheme (PECBMS) on abundance indexes collected throughout Europe from 1980 to 2019 and explored the driving forces behind our observed changes for each habitat type. We also apply GAMMs to model the overall changes in abundance indices of eight bird species that showed the highest variations (i.e., Locustella fluviatilis, Locustella naevia, Alcedo atthis, Bombycilla garrulus, Tetrax tetrax, Tringa totanus, Anthus campestris and Larus ridibundus). It was noted that the general abundance of birds decreased, with farmland birds suffering the biggest decline. Forest bird species population abundance was found to be quite varied; specialist species decreased as compared to generalists, which generally increased. [ABSTRACT FROM AUTHOR]

Although carry-over effects related to wintering habitat quality are known to influence population dynamics of migratory songbirds, the presence of breeding season carry-over is understudied in full annual cycle models. To test whether forest fragment size on the breeding grounds can impose negative carry-over effects on a migratory songbird, we fitted adult Wood Thrush (Hylocichla mustelina) with 1-year coded radio-tags in forest fragments ranging from 16 to 499 ha in southwestern Ontario during the 2016-2019 breeding seasons and utilized automated telemetry via the Motus Wildlife Tracking System to record fall migration timing and returns the following spring (apparent annual survival). To examine short-term effects of fragment size on breeding females, during the 2018 and 2019 breeding seasons, we collected blood samples during incubation to measure corticosterone levels and tracked complete reproductive success and nest timing. We found that Wood Thrushes breeding in small forest fragments were not subject to strong negative effects on body condition (mass, corticosterone), reproductive success, or timing of the last nest of the season. We found that the onset of fall migration departure was not delayed for birds nesting in small fragments, and that apparent annual survival was not linked to breeding fragment size. This suggests that habitat differences linked to fragment size were not strong enough to trigger the kinds of negative carry-over effects (delayed migration, lower reproductive success) that have been documented in other species as a result of poor wintering-ground habitat quality. The strength of breeding fragment size-induced seasonal carry-over remains a critical gap in full annual cycle models for other declining migratory songbirds. Our findings suggest that while the importance of preserving large forested areas is often prioritized in conservation projects, small forest fragments can also have high conservation value. [ABSTRACT FROM AUTHOR]

N‐mixture models were born in 2004 of the necessity to model animal population size from point counts with imperfect detection of individuals, where capture‐recapture methods are infeasible. Initially developed for applications where population size was assumed constant, N‐mixture models were extended in 2011 to include population dynamics, allowing application to populations whose size fluctuates during the study. A further extension in 2014 accommodates populations with multiple "states" such as age class or sex. More recent extensions model spatial movement of animals among habitat patches or the spatial spread of infectious disease in a human population. The core idea underlying this class of models is a hierarchical structure, where the observation model is defined conditional on the model for true abundance. This hierarchy allows researchers to incorporate information about observation and abundance processes, while permitting distinct inferences about elements affecting detection and those affecting abundance. Another benefit of the hierarchical approach is the ability to accommodate many existing sampling protocols such as removal sampling and distance sampling. One drawback to N‐mixture models is that since they estimate both abundance and detection from replicated but unmarked counts, model parameters may not be clearly identifiable. A second drawback is that when observed counts are large, calculating the N‐mixture likelihood is computationally infeasible. This difficulty motivated an approximate likelihood based on the normal approximation to the binomial. The normal approximation provides a diagnostic of parameter estimability based on the closed‐form expression of the Fisher information matrix for a multivariate normal likelihood. This article is categorized under:Data: Types and Structure > Image and Spatial DataStatistical Learning and Exploratory Methods of the Data Sciences > Modeling Methods [ABSTRACT FROM AUTHOR]

Understanding the relative contributions of historical and anthropogenic factors to declines in genetic diversity is important for informing conservation action. Using genome-wide DNA of fresh and historic specimens, including that of two species widely thought to be extinct, we investigated fluctuations in genetic diversity and present the first complete phylogenomic tree for all nine species of the threatened shorebird genus Numenius, known as whimbrels and curlews. Most species faced sharp declines in effective population size, a proxy for genetic diversity, soon after the Last Glacial Maximum (around 20,000 years ago). These declines occurred prior to the Anthropocene and in spite of an increase in the breeding area predicted by environmental niche modeling, suggesting that they were not caused by climatic or recent anthropogenic factors. Crucially, these genetic diversity declines coincide with mass extinctions of mammalian megafauna in the Northern Hemisphere. Among other factors, the demise of ecosystem-engineering megafauna which maintained open habitats may have been detrimental for grassland and tundra-breeding Numenius shorebirds. Our work suggests that the impact of historical factors such as megafaunal extinction may have had wider repercussions on present-day population dynamics of open habitat biota than previously appreciated. [ABSTRACT FROM AUTHOR]

Phellodendron has always been of great significance in promoting human health and ecological restoration. However, human activities and climate change have severely affected habitat, population dynamics and sustainable use of Phellodendron. Little is known about the geographical distribution pattern and their responses to climate change of Phellodendron. In order to reveal the impact of climate change on Phellodendron, we conducted a study based on natural distribution data of two species (297 occurrence points), 20 environmental factors, and an optimized MaxEnt model. Our results identified the main environmental factors influencing Phellodendron, predicted their potential geographical distribution, and assessed migration trends under climate change in China. Our analysis showed that Ph. amurense and Ph. chinense have potential suitable habitats of 62.89 × 104 and 70.71 × 104 km2, respectively. Temperature and precipitation were found to play an essential role in shaping the present geographical distribution of Phellodendron populations. Based on two future climate scenarios, we forecasted that the potential suitable habitat of Ph. amurense would decrease by 12.52% (SSP245) and increase by 25.28% (SSP585), while Ph. chinense would decline by 19.61% (SSP245) and 15.78% (SSP585) in the late‐21st century. The potential suitable habitats of Ph. amurense and Ph. chinense would shift to northward and westward, respectively. Hydrothermal change was found to be the primary driver of the suitable habitat of Phellodendron populations in the future. We recommend establishing nature reserves for existing Phellodendron populations, especially Ph. chinense. Our study provided a practical framework for the impact of climate change on the suitable habitat of Phellodendron species and guided regional cultivation, long‐term conservation, and sustainable use. [ABSTRACT FROM AUTHOR]

Classic ecological theory explains species coexistence in variable environments. While spatial variation is often treated as an intrinsic feature of a landscape, it may be shaped and even generated by the resident community. All species modify their local environment to some extent, driving changes that can feed back to affect the composition and coexistence of the community, potentially over timescales very different from population dynamics. We introduce a simple nested modeling framework for community dynamics in heterogeneous environments, including the possible evolution of heterogeneity over time due to community-environment feedbacks. We use this model to derive analytical conditions for species coexistence in environments where heterogeneity is either fixed or shaped by feedbacks. Among other results, our approach reveals how dispersal and environmental specialization interact to shape realized patterns of habitat association and demonstrates that environmental feedbacks can tune landscape conditions to allow the stable coexistence of any number of species. Our flexible modeling framework helps explain feedback dynamics that arise in a wide range of ecosystems and offers a generic platform for exploring the interplay between species and landscape diversity. [ABSTRACT FROM AUTHOR]

Coastal ecosystems act as spawning grounds, settlement areas or nurseries for a diversity of fish species. Today, these ecosystems are under various anthropogenic stressors. One of these disturbances is the structural modification of the shallow littoral by coastal infrastructure such as ports, piers, marinas and roads. Here, we investigate whether there are differences between modified (artificial) and non-modified (natural) habitats in central Greece in terms of the fish assemblage structure, species diversity and richness, fish abundance and the proportion of juveniles. We carried out underwater visual census from September 2020 to August 2021 across two habitats (natural and artificial) in three locations of central Greece. The fish community and Shannon diversity index did not vary across habitat type; however, both species richness and total abundance were significantly higher in artificial habitats. The abundance of five (out of ten examined in total) taxa was significantly affected by habitat type. Higher abundance in the artificial habitat in the warmer or more productive months was found, possibly relevant to food availability. The significance of habitat interactions with location and the temporal component in community composition and species abundance models indicated intense heterogeneity in species-specific occupancy and may be linked to the type and characteristics of artificial habitats. Modeling of the percentage of small-sized individuals indicated patterns of juvenile occupancy requiring further investigation about the potential role of artificial habitats for some species. Future research should examine the impact of specific artificial habitat types on population dynamics and investigate the implications of artificial habitat construction for conserving fish diversity and maintaining coastal ecosystem functioning. [ABSTRACT FROM AUTHOR]

Animals are inherently tied to nutritional resources of the landscape. Added cost of coping with environmental stressors, like disease, can exacerbate nutritional limitations. Pneumonia, a respiratory disease caused primarily by bacterial pathogens, has caused massive declines in populations of bighorn sheep (Ovis canadensis) throughout western North America. Nevertheless, population dynamics following a pneumonia epizootic vary across populations, which has spawned the idea that ecological conditions may play a role in regulating populations after a die‐off. We used 2 bighorn sheep populations with contrasting dynamics to test the hypothesis that habitat quality on summer range affects population dynamics following a pneumonia epizootic. We sampled over 700 vegetation transects and quantified nutrient content of 2,093 forage samples of 127 genera on summer ranges to compare habitat quality (macro‐ and micronutrients in forage, biomass, plant cover, and species diversity) between the ranges. The population exhibiting growth, higher recruitment, and better nutritional condition had over double the herbaceous biomass in their core foraging areas in summer than the population exhibiting decline, lower recruitment, and poorer nutritional status. The population experiencing growth also had more macro‐ and micronutrients available on their summer range as a function of higher biomass along with higher species diversity. Although winter range often is considered the nutritional bottleneck for ungulates, we demonstrate that the conditions of summer range can have consequences for population dynamics. Habitat quality should be incorporated when considering management objectives and population recovery of large herbivores in the presence of disease; interactions between habitat quality and population dynamics still apply and likely are amplified with additional stressors like disease. [ABSTRACT FROM AUTHOR]

Climate and landcover change can have synergistic impacts on wildlife populations, but the pervasiveness of these threats and factors that buffer them remain unclear despite important implications for conservation. I evaluated the additive and interactive effects of spatiotemporal variation in temperature, precipitation, and landcover change on annual territory occupancy, colonization, and extinction of a threatened top‐predator, the ferruginous pygmy‐owl (Glaucidium brasilianum), across a vast binational region of the Sonoran Desert over 16 years. I also assessed how local habitat quality and regional population size mediate impacts of these stressors. Despite significant bivariate associations between occupancy and temperature, precipitation, and landcover change, evidence for interactions was much greater than for additive effects. Occupancy of territories imbedded in increasingly disturbed landscapes declined at greater rates with warming winter temperatures, but the temperature had little effect in intact landscapes suggesting they buffer impacts of climate warming. Occupancy increased markedly with precipitation due likely to major positive impacts on prey, but again, interactive effects were stronger given territories of higher quality amplified benefits of precipitation. Impacts of landcover change and habitat quality on extinction depended markedly on regional population sizes. When populations were small and few potential colonists were present, high‐quality habitat and low landcover change failed to reduce extinction. When populations were large, however, high‐quality habitat and more intact landscapes, which best foster dispersal, reduced extinction. Hence, complex interacting processes linked to the effects of precipitation and habitat quality on carrying capacity, landcover change on habitat connectivity and vulnerability to rising temperatures, and local population sizes simultaneously drove dynamics. Efforts to identify and protect high‐quality habitat and limit landcover change can enhance conservation but will be most efficient in intact landscapes. Efforts to enhance local habitat quality and quantity, and directly augment populations should consider broader landscape contexts linked to habitat connectivity and potential source populations. [ABSTRACT FROM AUTHOR]

Unravelling the relationships between insect population dynamics and habitat properties is often complex. Established theoretical concepts, which predict an influence of available resources on sex determination, have often not been tested with quantitative field data. Cavity-nesting Hymenoptera are suitable to assess the influence of habitat properties on reproductive parameters, as haplodiploidy enables direct responses to local conditions. We hypothesize that with increasing resource availability, the population sex ratio (share of females per site), sex allocation preference per individual offspring (the probability of producing either a male or a female offspring per brood cell) and resource allocation per individual offspring will be favouring towards females. We sampled offspring of Osmia cornuta, Osmia caerulescens and Trypoxylon figulus and their resource provisions using trap nests on 30 study sites in an agricultural landscape in southwest Germany, from March to August 2020. The potential influence of resource availability, landscape variables, temperature, seasonal progression, and nesting opportunities on sex and resource provisions was tested. Population sex ratio was not related to habitat properties. Sex allocation preference in the three species, however, depended on several variables including cavity size and seasonal progression, with pronounced differences amongst species. Individual resource provisioning mainly differed between sexes, as male larvae received less provisions than female larvae. As there was no influence of resource availability, we conclude that the sex ratio of established populations was balanced at the selected study sites by available resources in the landscape. At the individual scale, sex and resource allocation were influenced in species-specific ways. As such, sex determination and resource allocation are essential life history properties of sexually reproducing organisms. [ABSTRACT FROM AUTHOR]

Context: Spatial occupancy and local abundance of species often positively covary, but the mechanisms driving this widespread relationship are poorly understood. Resource dynamics and habitat changes have been suggested as potential drivers, but long-term studies relating them to abundance and occupancy are rare. In this 34-year study of acorn woodpeckers (Melanerpes formicivorus), a cooperatively breeding species, we observed a paradoxical response to changes in habitat composition: despite a reduction in the availability of high-quality breeding habitat, the population increased considerably. Objectives: We investigated the role of annual variation in food availability and long-term changes in habitat composition as predictors of population dynamics. Methods: Using model selection, we contrasted competing hypotheses on the effects of changing resource availability on occupancy and social group size across three spatial scales: territory, neighborhood, and landscape. Results: The increase in abundance was largely determined by the formation of new social groups, driven by a landscape-level expansion of canopy cover and its interaction with neighborhood-level acorn abundance, indicative of long-term increases in overall acorn productivity. Group size increased with neighborhood acorn crop two years earlier but groups were smaller in territories with more canopy cover. Conclusions: Our results indicate that scale-dependent processes can result in paradoxical relationships in systems with spatial and temporal resource heterogeneity. Moreover, the findings support the role of resources in driving changes in abundance and occupancy at a landscape scale, suggesting that colonization of marginal habitat drives the positive occupancy-abundance relationship in this cooperatively breeding species. [ABSTRACT FROM AUTHOR]

Habitat suitability difference between sexes results in sex-specific dispersal. Although this behaviour is one of the key factors in understanding population dynamics, there are limited studies to evaluate it in arboreal species. We studied the distribution of the Indian Giant Squirrel (IGS; Ratufa indica maxima) from a sex perspective. We also evaluated potentiallly suitable habitat types for the species in the Nelliyampathy Reserve Forest, Western Ghats, Kerala, India. We used the sweep survey method to record the distribution pattern of squirrels and analysed the influence of climatic layers and other variables on the distribution using MaxEnt. The study revealed that there was a difference between the sexes in habitat selection. Males preferred more land-use types than females, which were restricted to only certain land-use types. Some of the major factors that determined the distribution of species were distance from urban settlement (50.1%), distance from shade plantation (23.2%), distance from rocky outcrop (9.2%), minimum temperature of the coldest month (9%) and precipitation of the wettest quarter (8.5%). The final MaxEnt model output predicted 49.07% suitable habitat for IGS, of which 45.47% and 34.42% were suitable for males and females respectively, with an overlap of 30.82% between the sexes. We suggest that it would be important to include a sex perspective in species habitat suitability studies in order to gain insights into sex-related habitat specificity and its role in dispersal. [ABSTRACT FROM AUTHOR]

Long‐distance movements are hypothesized to positively influence population size and stability of mobile species. We tested this hypothesis with a novel modeling approach in which moving herbivores interact with the environment created by a dynamic global vegetation model using highly mobile Mongolian gazelles in the eastern Mongolian grasslands as a case study. Gazelle population dynamics were modeled from 1901 to 2018 under two scenarios, one allowing free movement and one restricting movement. Gazelles were 2.2 times more abundant when they could move freely and were extirpated in 71% of the study area when mobility was restricted. Mobility resulted in greater population increases during times of abundant forage and smaller population decreases during drought. Reduced thermoregulatory costs associated with climate change, combined with an increase in vegetation biomass, increased gazelle abundance. Since high abundances often resulted in overgrazing and, thus, extirpation when movement was restricted, mobility had an important role in maintaining higher densities. The novel modeling approach shows how accounting for not just herbivore but also plant ecophysiology can improve our understanding of the population dynamics of highly mobile herbivores, in particular when examining the effects of habitat and climate change. Since the model simulates herbivores based on general physiological mechanisms that apply across large herbivores and the vegetation model can be applied globally, it is possible to adapt the model to other large‐herbivore systems. [ABSTRACT FROM AUTHOR]

Simple Summary: Ecological characteristics of the two economically important Schizothorax wangchiachii populations from the upper Yangtze River were compared. Their age structures were similar, but the growth coefficient, initial sexual maturity age and age at first capture were significantly different between the two populations. Both populations were in an overfishing state due to the current fishing intensity. These results can provide information for planning additional resource protection for Schizothorax wangchiachii. To explore the differences in the growth characteristics and population dynamics of Schizothorax wangchiachii populations in the Jinsha River (JSR) and the Yalong River (YLR), samples were collected in the upper reaches of the JSR (n = 230) from 2019 to 2020 and the middle reaches of the YLR (n = 187) from 2017 to 2018. In the JSR and YLR populations, the age range was 11 and 12 years old, respectively, and the best growth equation was the Von Bertalanffy equation. The comparative analysis of the two populations showed that the growth coefficient, initial sexual maturity age and age at first capture of the YLR population were greater than those of the JSR population. Comparing the mortality rates of the two groups, we found that the YLR population had the higher female mortality rate (0.658 years−1) and the lower male mortality rate (0.453 years−1). Our assessment of the three natural mortality rates showed that the Fcur of both male and female populations was greater than F25%, indicating that both populations were in an overexploited state. Therefore, we suggest considering the two groups as separate protection units and implementing management measures such as ecological regulation, restoration of tributary habitat and strengthening of fishing ban monitoring to protect their resources. [ABSTRACT FROM AUTHOR]

Understanding the processes governing population dynamics is important for effective conservation and environmental management. Disentangling the relative role of density‐dependent versus density‐independent processes on population dynamics is often made difficult by the inability to control for abiotic or biotic factors, but long‐term datasets are invaluable in this pursuit. We used a 14‐year dataset from the Logan River, Utah, to assess long‐term trends in abundance and evidence of density‐dependent and density‐independent effects on population dynamics of Paiute sculpin (Cottus beldingii) across six sites. Additionally, we evaluated the feeding ecology of sculpin over 4 years. Sculpin densities generally increased from upstream to downstream, and the annual per capita rate of increase was negatively and significantly correlated with sculpin density at four of six sites. We observed a negative relationship between total gut content and sculpin density but did not observe a negative relationship between relative condition and density. Sculpin displayed a generalist feeding strategy, and interannual differences in diet composition appeared to be influenced by interannual differences in flow, particularly years with higher magnitude flow. The observed spatial patterns in sculpin abundance throughout the watershed matched those of invasive brown trout (Salmo trutta), the top piscivore in the Logan River, and likely represent affinities for the suite of ecological conditions associated with downstream sections of the Logan River. Our results suggest that sculpin populations are regulated largely by density‐dependent processes and match those from other studies on sculpin population dynamics including a range of species and habitats that differ vastly in abiotic conditions. [ABSTRACT FROM AUTHOR]

To assess the population dynamics, abundance of bitterling species and two non-bitterling cyprinid species were investigated in Lake Kasumigaura, Japan. Fish capture was conducted at nine sites, including rivers or agricultural ditches independently flowing into the lake, every September from 2005 to 2013. Large fluctuations in the abundance of four bitterling species were observed during survey years. Regional population decline of Acheilognathus tabira erythropterus and Acheilognathus melanogaster was detected through 9 years of survey. In addition, spatial synchrony between bitterling species was also observed in the population dynamics. On the other hand, no significant synchrony was observed between bitterlings and the two non-bitterling species. Synchrony of native bitterlings declined with increasing distance, whereas that of Rhodeus ocellatus ocellatus was almost constant regardless of distance. These results supported that the spatially synchronous decline of bitterling species was caused by the Moran effect and dispersal. In other words, results of this study showed that factors that vary over a regional scale, such as climate, and the loss of connectivity among habitats may have contributed to the decline of bitterling species. [ABSTRACT FROM AUTHOR]

Most biological populations reside in landscapes that consist of many different patches of different quality. Different species differ in their movement behavior, habitat preference and growth rates. Historically, mathematical models for population dynamics have made many simplifying assumptions, such as a single patch or homogeneous landscapes. Recent models have begun to implement landscape heterogeneity and individual movement characteristics, but many of those are based on logistic growth and linear analysis of the zero state. We consider a two-patch model with more general growth functions that can include Allee effects. We prove the existence of steady states and classify their qualitative behavior. In some special cases, we explicitly calculate their stability and use these results to give conditions for when the system exhibits bistability, i.e., the simultaneous existence of two locally stable states. We also study bifurcations with respect to the size of habitat patches and give conditions for forward and backward bifurcations. [ABSTRACT FROM AUTHOR]

In this paper we present a model for a possible containment way of alien species invasions. It relies on the application of one or more stripes on the ground for which the survival conditions are harsher. After reviewing a number of possible threats for biodiversity that are the main motivation of this study, as well as a few instances of landscape disruption, we present a reaction–diffusion model and report the simulations results in various conditions. The inferences indicate that the diffusion process can be delayed, through the use of multiple obstacles, thereby allowing the possibility of taking alternative measures in order to contain the invasion, at least for some time. We discuss the diffusion delay in terms of the level of hostility, the length and the number of consecutive repetitions of the harsh environments. Comparisons on the parameter space show that the harshness and structural characteristics of the stripes are intertwined in a non-trivial way. Alternatively, the model can be used to ascertain the situations in which a population living in a territory can still thrive when its habitat is broken by artifacts, whether human-built or resulting from natural causes. Examples of this sort are presented in the final discussion. [ABSTRACT FROM AUTHOR]

Habitat loss is one of the biggest threats facing plant species nowadays. We formulate a simple mathematical model of seed dispersal on reduced habitats to discuss survival of the species in relation to the habitat size and seeds production rate. Seeds get dispersed around the mother plant via several agents in a random way. In our model, seeds landing sites are distributed according to a homogeneous Poisson point process with a constant rate on ℝ$$ \mathbb{R} $$. We will assume that each seed will successfully germinate and grow into a new plant with the same characteristics as the mother plant. The time is discrete, scaled according to generations of plants, or can represent years, since annual plants go through an entire growing cycle during 1 year. Then we will assume there are two symmetric barriers with respect to the origin and consider that the growth cannot evolve past the barriers. Imposing barriers correspond to the physical limitation of the habitat. We appeal to tools of probability theory to formalize and study such a model, which can be seen as a discrete‐time one‐dimensional branching random walk with barriers. By means of coupling techniques and the comparison with suitably constructed multitype branching processes, we localize the critical parameter of the process around which there is survival with positive probability or extinction almost surely. In addition, we consider a discrete‐space version of the model for which exact results are also obtained. [ABSTRACT FROM AUTHOR]

Rigorous understanding of how environmental conditions impact population dynamics is essential for species conservation, especially in mixed‐use landscapes where source–sink dynamics may be at play. Conservation of large carnivore populations in fragmented, human‐dominated landscapes is critical for their long‐term persistence. However, living in human‐dominated landscapes comes with myriad costs, including direct anthropogenic mortality and sublethal energetic costs. How these costs impact individual fitness and population dynamics are not fully understood, partly due to the difficulty in collecting long‐term demographic data for these species. Here, we analyzed an 11‐year dataset on puma (Puma concolor) space use, mortality, and reproduction in the Santa Cruz Mountains, California, USA, to quantify how living in a fragmented landscape impacts individual survival and population dynamics. Long‐term exposure to housing density drove mortality risk for female pumas, resulting in an 18‐percentage‐point reduction in annual survival for females in exurban versus remote areas. While the overall population growth rate appeared stable, reduced female survival in more developed areas resulted in source–sink dynamics across the study area, with 42.1% of the Santa Cruz Mountains exhibiting estimated population growth rates <1. Since habitat selection is often used as a proxy for habitat quality, we also assessed whether puma habitat selection predicted source and sink areas. Patterns of daytime puma habitat selection predicted source areas, while time‐of‐day‐independent habitat selection performed less well as a proxy. These results illuminate the individual‐ and population‐level consequences of habitat fragmentation for large carnivores, illustrating that habitat fragmentation can produce source–sink dynamics that may not be apparent from other metrics of habitat quality. Locally, conserving high‐quality source habitat within the Santa Cruz Mountains is necessary to support long‐term puma population persistence. More broadly, source–sink dynamics may at play for other carnivore populations in similar fragmented systems, and linking landscape conditions to population dynamics is essential for effective conservation. Caution should be used in inferring habitat quality from habitat selection alone, but these results shed light on metrics of selection that may be better or worse proxies to identify source areas for large carnivores. [ABSTRACT FROM AUTHOR]

Population dynamics of migratory species can be modeled using spatial bipartite networks in which nodes representing breeding and winter regions are distributed longitudinally and connected by links representing migratory movements. Understanding the factors that influence the connectivity and population size of such networks is important for effective conservation. In migration ecology terminology, strong migratory connectivity is a network with low node degree and weak or diffuse connectivity is a network with high node degree. We present a model of migration networks using a Lotka-Volterra system of differential equations in which each winter-breeding link is represented as a subpopulation which competes with other subpopulations that share breeding or winter regions. We analyze how habitat distribution and relative costs of migration paths affect the coexistence of subpopulations and hence, the connectivity pattern (weak, moderate or strong). We find that, in the absence of dispersal among subpopulations, strong connectivity occurs when winter habitat has the same longitudinal distribution as breeding habitat, and/or costs of cross-longitudinal migration are high. Moderate connectivity arises otherwise. Total population size is maximized when each longitudinal region has the same amount of breeding habitat as winter habitat and decreases with the costs of migration. Including dispersal leads to weak connectivity and reduces population size. Our results suggest that actions that conserve habitat so as to preserve matching habitat distributions and minimize costs of migration would be most effective. [ABSTRACT FROM AUTHOR]

Riparian vegetation is crucial for maintaining terrestrial and aquatic biodiversity, but it is threatened by land-use activities. To assess the ecological impacts of riparian vegetation conversion to an oil tea (Camellia oleifera) plantation, we quantified the responses of small mammals in two natural habitats (mature forest and flood-meadow) and in Camellia forests at the community, population, and individual level. We found that the community diversity was similar between Camellia forests and mature forests, but higher than the flood-meadow. Meanwhile, the community composition differed across three habitats, with Camellia forests favoring habitat generalist species. At the population level, Camellia forests and flood-meadow had a similar population density, which were higher than mature forests. At the individual level, Rattus nitidus was less sensitive to this conversion, but the body condition index of Niviventer confucianus was higher in Camellia forests than in mature forests, and Apodemus agrarius in Camellia forests had more ectoparasite load than in the flood-meadow, indicating a species-specific response to the impacts of oil tea plantation. Our study highlights that the occurrence of habitat generalist species and high ectoparasite loads may threaten regional biodiversity and increase the risk of parasite transmission with enlarging the oil tea plantation area within riparian zones. [ABSTRACT FROM AUTHOR]

Camera traps have become popular labor‐efficient and non‐invasive tools to study animal populations. The use of camera trap methods has largely focused on large animals and/or animals with identifiable features, with less attention being paid to small mammals, including rodents. Here we investigate the suitability of camera‐trap‐based abundance indices to monitor population dynamics in two species of voles with key functions in boreal and Arctic ecosystems, known for their high‐amplitude population cycles. The targeted species—gray‐sided vole (Myodes rufocanus) and tundra vole (Microtus oeconomus)—differ with respect to habitat use and spatial‐social organization, which allow us to assess whether such species traits influence the accuracy of the abundance indices. For both species, multiple live‐trapping grids yielding capture‐mark‐recapture (CMR) abundance estimates were matched with single tunnel‐based camera traps (CT) continuously recording passing animals. The sampling encompassed 3 years with contrasting abundances and phases of the population cycles. We used linear regressions to calibrate CT indices, based on species‐specific photo counts over different time windows, as a function of CMR‐abundance estimates. We then performed inverse regression to predict CMR abundances from CT indices and assess prediction accuracy. We found that CT indices (for windows maximizing goodness‐of‐fit of the calibration models) predicted adequately the CMR‐based estimates for the gray‐sided vole, but performed poorly for the tundra vole. However, spatially aggregating CT indices over nearby camera traps enabled reliable abundance indices also for the tundra vole. Such species differences imply that the design of camera trap studies of rodent population dynamics should be adapted to the species in focus, and adequate spatial replication must be considered. Overall, tunnel‐based camera traps yield much more temporally resolved abundance metrics than alternative methods, with a large potential for revealing new aspects of the multi‐annual population cycles of voles and other small mammal species they interact with. Camera traps provide a non‐invasive and labor‐efficient method for year round monitoring of wildlife. Here we validate abundance indices from tunnel‐based camera traps for two common cyclic species of small rodents. This work paves the way for camera traps to be included in year round monitoring programs of small rodents. [ABSTRACT FROM AUTHOR]

The inhomogeneous population distribution appears as various population densities or different types of dynamics in distant sites of the extended habitat and may arise due to, for example, the resettlement features, the internal population structure, and the population dynamics synchronization mechanisms between adjacent subpopulations. In this paper, we propose the model of the spatio-temporal dynamics of two-age-structured populations coupled by migration (metapopulation) with long-range displacement. We study mechanisms leading to inhomogeneous spatial distribution as a type of cluster synchronization of population dynamics. To study the spatial patterns and synchronization, we use the method of constructing spatio-temporal profiles and spatial return maps. We found that patterns with spots or stripes are typical spatial structures with synchronous dynamics. In most cases, the spatio-temporal dynamics are mixed with randomly located single populations with strong burst (outbreak) of population size (solitary states). As the coupling parameters decrease, the number of solitary states grows, and they increasingly synchronize and form the clusters of solitary states. As a result, there are the several clusters with different dynamics. The appearance of these spatial patterns most likely occurs due to the multistability of the local age-structured population, leading to the spatio-temporal multistability. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used to relate species occurrence and density to local environmental conditions, and often include a spatially correlated variable to account for spatial patterns in residuals. Ecologists have extended SDMs to include spatially varying coefficients (SVCs), where the response to a given covariate varies smoothly over space and time. However, SVCs see relatively little use perhaps because they remain less known relative to other SDM techniques. We therefore review ecological contexts where SVCs can improve the interpretability and descriptive power from SDMs, including local responses to regional indices that represent ecological teleconnections; density‐dependent habitat selection; spatially varying detectability; and context‐dependent covariate responses that represent interactions with unmeasured covariates. We then illustrate three additional examples in detail using the vector autoregressive spatio‐temporal (VAST) model. First, a spatially varying decadal trends model identifies decadal trends for arrowtooth flounder Atheresthes stomias density in the Bering Sea from 1982 to 2019. Second, a trait‐based joint SDM highlights the role of body size and temperature in spatial community assembly in the Gulf of Alaska. Third, an age‐structured SDM for walleye pollock Gadus chalcogrammus in the Bering Sea contrasts cohorts with broad spatial distributions (1996 and 2009) and those that are more spatially constrained (2002 and 2015). We conclude that SVCs extend SDMs to address a wide variety of ecological contexts and can be used to better understand a range of ecological processes, e.g. density dependence, community assembly and population dynamics. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the population characteristics of spirlin, Alburnoides bipunctatus, in Serbia, since this small fish species is facing a severe decline in its abundance and its natural habitats in Europe. We investigated the spirlin population dynamics, including size, age structure, growth pattern, mortality, and exploitation rate. Additionally, we used the Uniform Manifold Approximation and Projection approach with the Decision Tree algorithm to investigate the influence of different environmental parameters on the population parameters to unveil which factors shape the abundance and distribution of spirlin. The results showed that the highest values of production, abundance, and biomass were estimated in sites with low temperature, optimal pH, and well-oxygenated water, even though we found them in heavily polluted waters with extremely high values of conductivity. Moreover, we observed a pattern of migratory behavior, in which spirlin migrate upstream to sites at a higher altitude in early summer and autumn. Despite the putative vulnerability and high sensitivity of spirlin populations, our results showed that the species was abundant, occurring in altered habitats (due to pollution, climate change, anthropogenic pressure, etc.). [ABSTRACT FROM AUTHOR]

'Slow science' approaches to generating authoritative longitudinal datasets for long-term monitoring are fundamental to conservation biology. Following reports of significant arthropod declines worldwide, and recent climate-driven disasters such as the devastating 'Black Summer' bushfires of 2019-2020, there has been a renewed focus on invertebrate conservation in Australia and further calls for informative baseline datasets with which to understand increasingly rapid biotic change. Trapdoor spiders of the infraorder Mygalomorphae, in particular, have been the subject of decades of research highlighting their sensitivity to environmental change and their special significance to conservation biology. In 2019, the senior author and collaborators introduced within this journal a new long-term monitoring study system for an Australian mygalomorph spider (Euoplos grandis Wilson & Rix, 2019; family Idiopidae), then in its infancy with just 18 months of quantitative demographic data. In the current study, we extend and build upon that work and provide a synthesis of demographic information accumulated over half a decade, resulting in 166 collective years' worth of times-series data from 101 individual spiders. We infer an estimated average cumulative growth curve for the species based on census data from 77 spiders, with evidence for a 7+-year juvenile female growth period and a potential life span for adult females of over 20 years. Passive surveillance using a camera trap deployed at the study site for 8 months resulted in significant advances in our understanding of the biology and behaviour of E. grandis, with a suite of behaviours observed for the first time, including rarely documented interactions with conspecifics, potential predators and prey. We further summarise the results of maximum entropy potential habitat modelling as informed by extensive on-ground surveys and a refined taxonomy, and provide an updated conservation assessment using the International Union for Conservation of Nature (IUCN) criteria. These results reveal that E. grandis is a Vulnerable threatened species endemic to the highly fragmented southern Brigalow Belt bioregion, with population dynamics and life history characteristics that underscore the considerable sensitivity of Australian idiopid trapdoor spiders to a multitude of threatening processes. [ABSTRACT FROM AUTHOR]

Dispersal is a key influence on species' persistence, particularly in the context of habitat fragmentation and environmental change. Previously, residual population synchrony has been demonstrated to be an effective proxy for dispersal in mobile butterflies (Powney et al. 2012). Here, we highlight the utility and limitations of population synchrony as an indicator of functional connectivity and persistence, at a range of spatial scales, in a specialist, sedentary butterfly. While at the local scale, population synchrony is likely indicative of dispersal in the pearl-bordered fritillary, Boloria euphrosyne, over larger scales, habitat is likely to influence population dynamics. Although declines in local-scale synchrony conformed to typical movement in this species, synchrony showed no significant trend with distance when studied at larger (between-site) scales. By focusing on specific site comparisons, we draw the conclusion that heterogeneity in habitat successional stage drives asynchrony between sites at larger distances and is, therefore, likely to be a more important driver of population dynamics over large distances than dispersal. Within-site assessments of synchrony highlight differences in dispersal based on habitat type, with movement shown to be most inhibited between transect sections with contrasting habitat permeability. While synchrony has implications for metapopulation stability and extinction risk, no significant difference was found in average site synchrony between sites that had gone extinct during the study period and those remaining occupied. We demonstrate that population synchrony may be used to assess local-scale movement between sedentary populations, as well as to understand barriers to dispersal and guide conservation management. [ABSTRACT FROM AUTHOR]

Aim: Despite the complexity of population dynamics, most studies concerning current changes in bird populations reduce the trajectory of population change to a linear trend. This may hide more complex patterns reflecting responses of bird populations to changing anthropogenic pressures. Here, we address this complexity by means of multivariate analysis and attribute different components of bird population dynamics to different potential drivers. Location: Czech Republic. Methods: We used data on population trajectories (1982–2019) of 111 common breeding bird species, decomposed them into independent components by means of the principal component analysis (PCA), and related these components to multiple potential drivers comprising climate, land use change and species' life histories. Results: The first two ordination axes explained substantial proportion of variability of population dynamics (42.0 and 12.5% of variation in PC1 and PC2 respectively). The first axis captured linear population trend. Species with increasing populations were characterized mostly by long lifespan and warmer climatic niches. The effect of habitat was less pronounced but still significant, with negative trends being typical for farmland birds, while positive trends characterized birds of deciduous forests. The second axis captured the contrast between hump‐shaped and U‐shaped population trajectories and was even more strongly associated with species traits. Species migrating longer distances and species with narrower temperature niches revealed hump‐shaped population trends, so that their populations mostly increased before 2000 and then declined. These patterns are supported by the trends of total abundances of respective ecological groups. Main Conclusion: Although habitat transformation apparently drives population trajectories in some species groups, climate change and associated species traits represent crucial drivers of complex population dynamics of central European birds. Decomposing population dynamics into separate components brings unique insights into non‐trivial patterns of population change and their drivers, and may potentially indicate changes in the regime of anthropogenic effects on biodiversity. [ABSTRACT FROM AUTHOR]

Early‐life conditions can have long‐term fitness consequences. However, it is still unclear what optimal rearing conditions are, especially for long‐lived carnivores. A more diverse diet ('balanced diet') might optimize nutrient availability and allow young to make experiences with a larger diversity of prey, whereas a narrow diet breadth ('specialized diet') might result in overall higher energy net gain. A diet that is dominated by a specific prey type (i.e. fish, 'prey type hypothesis') might be beneficial or detrimental, depending for example, on its toxicity or contaminant load.Generalist predators such as the white‐tailed eagle Haliaeetus albicilla provide an interesting possibility to examine the relationship between early life diet and long‐term offspring survival. In the Åland Islands, an archipelago in the Baltic Sea, white‐tailed eagles live in various coastal habitats and feed on highly variable proportions of birds and fish.We use data from 21,116 prey individuals that were collected from 120 territories during the annual surveys, to examine how early‐life diet is associated with apparent annual survival of 574 ringed and molecular‐sexed eaglets. We supplement this analysis by assessing the relationships between diet, reproductive performance and nestling physical condition, to consider whether they are confounding with possible long‐term associations.We find that early‐life diet is associated with long‐term fitness: Nestlings that are fed a diverse diet are in lower physical condition but have higher survival rates. Eagles that are fed more fish as nestlings have lower survival as breeding‐age adults, but territories associated with fish‐rich diets have higher breeding success.Our results show that young carnivores benefit from a high diversity of prey in their natal territory, either through a nutritional or learning benefit, explaining the higher survival rates. The strong relationship between early‐life diet and adult survival suggests that early life shapes adult foraging decisions and that eating fish is associated with high costs. This could be due to high levels of contaminants or high competition for fish‐rich territories. Long‐lasting consequences of early‐life diet are likely not only limited to individual‐level consequences but have the potential to drive eco‐evolutionary dynamics in this population. [ABSTRACT FROM AUTHOR]

Effective survey methods are paramount to measure changes in species distribution, populations dynamics and to guide conservation. Mist-netting and passive acoustic monitoring are two of the most used techniques to sample bats assemblages. Yet, despite the great potential of low-cost autonomous ultrasound recorders in surveying bat assemblages, we lack thorough assessments of their performance in relation to more established survey methods. Taking advantage of the rich bat fauna of the northeastern Brazilian Amazon, we set out to i) investigate the complementarity of mist-netting and acoustic surveys in sampling bats in forest and savannah habitats in the Savannahs of Amapá and ii) undertake a cost-effectiveness evaluation of using one, two or three recorders per sampling site to simultaneously survey bat assemblages. The two methods show complementary, and overall species diversity recorded with mist nets was higher than with acoustic recorders. However, species diversity was higher with acoustic recorders than with mist nets when considering a reduced (n < 3) number of transects. In addition, we found a gain in species diversity when using more than one acoustic recorder in forest habitats, despite the low cost-effectiveness. However, there were no differences between the diversity using one, two or three acoustic recorders in savannah. Due to possible device malfunction, we recommend the use of at least two acoustic recorders in both habitats to reduce the likelihood of data loss. The use of low-cost bioacoustic recorders in bat surveys can help to address critical knowledge gaps for poorly known aerial-hawking insectivores and support evidence-based conservation strategies. [ABSTRACT FROM AUTHOR]

In this paper, we study a system of nonlinear partial differential equations that models the population dynamics of two competitive species both under Allee effects. The consideration of the model includes Logistic growth with Allee effects, Lotka-Volterra competition, diffusion, initial density and boundary conditions on the habitat. In the reaction-diffusion system, we employ the method of upper and lower solutions to address questions on self-elimination or persistence, as well as permanence or competitive exclusion. Specific conditions on biological parameters are explicitly given for extinction, coexistence and competitive exclusion of the species under various boundary conditions. Numerical simulations for the model are demonstrated to illustrate our results from mathematical analysis. [ABSTRACT FROM AUTHOR]

We used data from a five-year study at two focal breeding wetlands of a single Crawfish Frog (Rana areolata) population to demonstrate the relative importance and potential of tadpole survival as a target for population management. We concurrently estimated 11 vital rates in the field and used a females-only matrix projection model to estimate elasticities of demographic rates. We then simulated stochastic population dynamics at each wetland with and without immigration to estimate the intrinsic capacity for each focal breeding wetland to sustain a Crawfish Frog breeding population and the likelihood of breeding population persistence at each wetland. Elasticity of tadpole survival was second only to juvenile survival elasticity and 1.34-2.04 times greater than adult survival elasticity. Projections indicated that the Crawfish Frog population was not at risk of extinction but only one breeding site was capable of self-sustaining a breeding population. Because of low tadpole survival, the other breeding site was completely dependent on immigration to persist and was functioning as a population sink. Despite higher variability compared to terrestrial vital rates, larval survival did have a strong effect on population growth. Tadpole survival at the more productive breeding site was density dependent and likely related to wetland vegetation and predator and competitor abundance. Two additional findings were that annual survival of frogs following their first known breeding event was 48% lower compared to survival of frogs that had bred in two or more prior years, and adult temporary emigration from the breeding population was moderately high. Our study demonstrates the benefits of using population models that integrate density-dependent processes, temporary emigration from the breeding population, and state-specific adult survival, to identify larval habitats that function as population sinks and limit current population size and persistence probability. We contend that tadpole survival is an important and feasible habitat management target within broader conservation strategies for Crawfish Frogs and other amphibian species. [ABSTRACT FROM AUTHOR]

The fate of natural populations is mediated by complex interactions among vital rates, which can vary within and among years. Although the effects of random, among‐year variation in vital rates have been studied extensively, relatively little is known about how periodic, nonrandom variation in vital rates affects populations. This knowledge gap is potentially alarming as global environmental change is projected to alter common periodic variations, such as seasonality. We investigated the effects of changes in vital‐rate periodicity on populations of three species representing different forms of adaptation to periodic environments: the yellow‐bellied marmot (Marmota flaviventer), adapted to strong seasonality in snowfall; the meerkat (Suricata suricatta), adapted to inter‐annual stochasticity as well as seasonal patterns in rainfall; and the dewy pine (Drosophyllum lusitanicum), adapted to fire regimes and periodic post‐fire habitat succession. To assess how changes in periodicity affect population growth, we parameterized periodic matrix population models and projected population dynamics under different scenarios of perturbations in the strength of vital‐rate periodicity. We assessed the effects of such perturbations on various metrics describing population dynamics, including the stochastic growth rate, log λS. Overall, perturbing the strength of periodicity had strong effects on population dynamics in all three study species. For the marmots, log λS decreased with increased seasonal differences in adult survival. For the meerkats, density dependence buffered the effects of perturbations of periodicity on log λS. Finally, dewy pines were negatively affected by changes in natural post‐fire succession under stochastic or periodic fire regimes with fires occurring every 30 years, but were buffered by density dependence from such changes under presumed more frequent fires or large‐scale disturbances. We show that changes in the strength of vital‐rate periodicity can have diverse but strong effects on population dynamics across different life histories. Populations buffered from inter‐annual vital‐rate variation can be affected substantially by changes in environmentally driven vital‐rate periodic patterns; however, the effects of such changes can be masked in analyses focusing on inter‐annual variation. As most ecosystems are affected by periodic variations in the environment such as seasonality, assessing their contributions to population viability for future global‐change research is crucial. [ABSTRACT FROM AUTHOR]

We used the mark-recapture method to gather fundamental information on the population dynamics of Ischnura elegans (Vander Linden, 1820) in an arid region of central Iran. Ischnura elegans expresses female-limited colour polymorphism. We investigated sex and female morphs differences in survival and capture probabilities, space use patterns and spatial density. We used Cormack–Jolly–Seber and spatial capture-recapture models. The estimated capture probability for males was lower than females. The survival probability was not different between either males and females or gynomorphs and andromorphs. We found support for sex differences in density and detection probability, and female morphs differences in density, space use and detection probability. Based on our results the extreme conditions of arid regions can lead to a male-biased dispersal. Our findings also confirm the existence of behavioural differences between andromorph and gynomorph females and suggest a within species spatial habitat partitioning. [ABSTRACT FROM AUTHOR]

Chilgoza pine (Pinus gerardiana Wall. ex D. Don) is one of the multipurpose, endemic and near-threatened species of Himalayan region. The population of Chilgoza pine is decreasing rapidly due to over exploitation and habitat degradation. Chilgoza pine serves for its edible pine nuts, seeds are locally known as Miri, Chilgoza and Neoja is most important cash crops of tribal people residing in Luj and Dharwas villages of Pangi valley and seed are very expensive, sold at approximately 2500–4500 rupees per kilogram. Due to over exploitation and habitat degradation, natural regeneration of the species is very poor in the area. Keeping in view of the ecological and economical importance of the species for the tribal community, the population ecology and regeneration pattern were documented in Pangi Valley, Chamba District of Himachal Pradesh located in north western Himalaya. Therefore, regular monitoring of the populations of Pinus gerardiana for understanding the population dynamics is required. Afforestation in specific habitat, mass multiplication following conventional propagation methods and educational and awareness programmes for the conservation have been suggested. [ABSTRACT FROM AUTHOR]

Many aspects of global ecosystem degradation are well known, but the ecological implications of variation in these effects over scales of kilometers and years have not been widely considered. On tropical coral reefs, kilometer-scale variation in environmental conditions promotes a spatial mosaic of coral communities in which spatial insurance effects could enhance community stability. To evaluate whether these effects are important on coral reefs, we explored variation over 2006–2019 in coral community structure and environmental conditions in Moorea, French Polynesia. We studied coral community structure at a single site with fringing, back reef, and fore reef habitats, and used this system to explore associations among community asynchrony, asynchrony of environmental conditions, and community stability. Coral community structure varied asynchronously among habitats, and variation among habitats in the daily range in seawater temperature suggested it could be a factor contributing to the variation in coral community structure. Wave forced seawater flow connected the habitats and facilitated larval exchange among them, but this effect differed in strength among years, and accentuated periodic connectivity among habitats at 1–7 year intervals. At this site, connected habitats harboring taxonomically similar coral assemblages and exhibiting asynchronous population dynamics can provide insurance against extirpation, and may promote community stability. If these effects apply at larger spatial scale, then among-habitat community asynchrony is likely to play an important role in determining reef-wide coral community resilience. [ABSTRACT FROM AUTHOR]

Landscape‐scale conservation that considers metapopulation dynamics will be essential for preventing declines of species facing multiple threats to their survival. Toward this end, we developed a novel approach that combines occurrence records, spatial–environmental data, and genetic information to model habitat, connectivity, and patterns of genetic structure and link spatial attributes to underlying ecological mechanisms. Using the threatened northern quoll (Dasyurus hallucatus) as a case study, we applied this approach to address the need for conservation decision‐making tools that promote resilient metapopulations of this threatened species in the Pilbara, Western Australia, a multiuse landscape that is a hotspot for biodiversity and mining. Habitat and connectivity were predicted by different landscape characteristics. Whereas habitat suitability was overwhelmingly driven by terrain ruggedness, dispersal was facilitated by proximity to watercourses. Although there is limited evidence for major physical barriers in the Pilbara, areas with high silt and clay content (i.e., alluvial and hardpan plains) showed high resistance to dispersal. Climate subtlety shaped distributions and patterns of genetic turnover, suggesting the potential for local adaptation. By understanding these spatial–environmental associations and linking them to life‐history and metapopulation dynamics, we highlight opportunities to provide targeted species management. To support this, we have created habitat, connectivity, and genetic uniqueness maps for conservation decision‐making in the region. These tools have the potential to provide a more holistic approach to conservation in multiuse landscapes globally. [ABSTRACT FROM AUTHOR]

Simple Summary: This article demonstrates the dampening of small mammal population dynamics and describes the numerical response of owls in Latvia. Numerical response was measured by diet, breeding performance, and trends in population change of six owl species. The responses varied among owl species, ranging from increased food niche breadth in more plastic species to reduced breeding performance and decreasing population size in more specialized species. The eagle owl seems to depend on voles in the previous autumn via the carry-over effect as measured by reduced breeding performance. Species more specialized in breeding in mature forests showed greater population declines, since mature forests are vital for owl breeding, as well as hold higher vole densities. Strong numerical and functional responses of owls to voles in cyclic environments are well known. However, there is insufficient knowledge from the boreonemoral region in particular, with depleted populations of small mammals. In this study, we describe the dynamics of the small mammal population in Latvia from 1991 to 2016 and link them to owl population characteristics. We used food niche breadth, number of fledglings, and population trends to lay out the numerical response of six owl species to dampened small mammal population cycles. We found temporarily increasing food niche breadth in tawny and Ural owls. There were no other responses in the tawny owl, whereas the breeding performance of three forest specialist species—pygmy, Tengmalm's, and Ural owls—corresponded to the vole crash years in Fennoscandia. Moreover, the populations of forest specialist owls decreased, and the change in the Ural owl population can be attributed to the depletion of small mammal populations. We found evidence of a carry-over effect in the eagle owl arising from a strong correlation of declining breeding performance with the small mammal abundance indices in the previous autumn. We conclude that dampening of the small mammal population cycles is an important covariate of the likely effects of habitat destruction that needs to be investigated further, with stronger responses in more specialized (to prey or habitat) species. [ABSTRACT FROM AUTHOR]

Understanding the demographic drivers of range contractions is important for predicting species' responses to climate change; however, few studies have examined the effects of climate change on survival and recruitment across species' ranges. We show that climate change can drive trailing edge range contractions through the effects on apparent survival, and potentially recruitment, in a migratory songbird. We assessed the demographic drivers of trailing edge range contractions using a long‐term demography dataset for the black‐throated blue warbler (Setophaga caerulescens) collected across elevational climate gradients at the trailing edge and core of the breeding range. We used a Bayesian hierarchical model to estimate the effect of climate change on apparent survival and recruitment and to forecast population viability at study plots through 2040. The trailing edge population at the low‐elevation plot became locally extinct by 2017. The local population at the mid‐elevation plot at the trailing edge gradually declined and is predicted to become extirpated by 2040. Population declines were associated with warming temperatures at the mid‐elevation plot, although results were more equivocal at the low‐elevation plot where we had fewer years of data. Population density was stable or increasing at the range core, although warming temperatures are predicted to cause population declines by 2040 at the low‐elevation plot. This result suggests that even populations within the geographic core of the range are vulnerable to climate change. The demographic drivers of local population declines varied between study plots, but warming temperatures were frequently associated with declining rates of population growth and apparent survival. Declining apparent survival in our study system is likely to be associated with increased adult emigration away from poor‐quality habitats. Our results suggest that demographic responses to warming temperatures are complex and dependent on local conditions and geographic range position, but spatial variation in population declines is consistent with the climate‐mediated range shift hypothesis. Local populations of black‐throated blue warblers near the warm‐edge range boundary at low latitudes and low elevations are likely to be the most vulnerable to climate change, potentially leading to local extirpation and range contractions. [ABSTRACT FROM AUTHOR]