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The rapid growth of the world's population and its environmental impact has increased the demand for effective water treatment methods. Surface water systems, including rivers, streams, lakes, and ponds, have suffered contamination, leading to the urgent need for effective contaminant removal. Organic nitrogen compounds and nitrates are of particular concern because they pose risks to health and can cause environmental damage. However, traditional water‐treatment methods often prove ineffective for addressing these issues. For this reason, this research focuses on harnessing the capabilities of nitrifying bacteria to denitrify organic nitrogen compounds in water, exploring various bacterial strains, their functions, and their ability to obtain sources of carbon. The study also investigates innovative approaches such as biofilm systems, mixed cultures, and combined processes, which have shown stronger potential for nitrogen removal. Overall, it provides valuable insights into the use of nitrifying bacteria‐based technologies for water remediation in the face of growing environmental challenges. [ABSTRACT FROM AUTHOR]

The UN projects that world population will peak at 10.3 billion in 2084, a 2.1 billion increase from 2024. Can the world provide food, water, and other resources to 10.3 billion people? How will additional population exacerbate resource challenges and worsen climate change? This paper analyzes these questions by looking at the last 60 years and by simulating the future impact of population growth and rising incomes on food, water, energy, and CO2 emissions. Looking back, food production has increased faster than the population in all regions, and we have not experienced significant shortages in nonrenewable resources. The history of water and CO2 emissions is less encouraging, however, with declining water levels in many aquifers and global warming threatening to undermine progress in all areas. Looking forward, population growth will be concentrated in poor countries, while rich countries, with higher consumption levels and emissions, will experience population decline. Population growth is projected to significantly increase demand for food and water in coming decades but is projected to have only modest impacts on energy and CO2, with population decline in high‐emission higher income countries more than offsetting the impact of population growth in low‐emission lower‐income countries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Egg parasitoids are important biological control agents of lepidopteran pests of agricultural crops. Trichogramma evanescens Westwood and T. pintoi Voegele (Hymenoptera: Trichogrammatidae) are egg parasitoids with worldwide importance. The parasitoid selection necessitates comparative assessment of the life table traits and functional response analysis to provide insights into their effectiveness in pest control. In this study, we examined their life table traits including survivorship and reproductivity, and functional response and associated parameters i.e., attack coefficient and handling time. RESULTS: Life table parameters, using age‐stage, two‐sex theory, revealed similar survival and reproductive strategies for both species. For example, the female longevity, oviposition days and fecundity did not differ between both species. Exceptionally, the male longevity of T. evanescens was shorter than that of T. pintoi. The population growth parameters such as gross reproductive rate (GRR), net reproductive rate (R0), intrinsic rate of increase (r), finite rate of increase (λ), and mean generation time (T) did not differ between species. The polynomial logistic regression yielded a type III functional response and a non‐linear least square analysis revealed different attack coefficient and similar handling time. However, their parasitism rate differed between the lowest (five eggs) and highest (80 eggs) initial host egg densities such that T. evanescens had a lower parasitism rate at the lowest density and higher parasitism rate at the highest density. CONCLUSION: The similarity in survival strategies and minor differences in host handling of both parasitoids are discussed in terms of relevance to applied biological control applications and evolutionary traits. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACT The threespine stickleback, Gasterosteus aculeatus, has undergone dramatic increases in abundance in parts of its historical native range, and it is also undergoing a major range expansion. We review available information and discuss the vectors and sources of the species' range expansions, the genetic characteristics of recently founded populations and the ecological consequences of both stickleback introductions and increases in abundance. Dramatic range expansions occurred in the Caspian Sea drainage, large rivers in the Black Sea drainage, reservoirs of the Rhine basin, isolated lakes in North America and Japan and remote islands in the Arctic. Likely reasons for these range expansions include canal construction, accidental inclusion with stocking of commercially valuable fish, intentional release by aquarists and fishermen and climate change. In some cases, range expansions of stickleback were likely facilitated by genetic admixture of previously separated lineages, as well as by high‐standing genetic variation that promotes rapid adaptation to new habitats. Accordingly, range expansions are often accompanied by striking increases in abundance, although these are two distinct processes. Notably, population growth within the species' native range, particularly in the White and Baltic Seas, has been observed alongside expansions into new areas. Where stickleback colonise new habitats or increase in abundance, extensive ecological impacts on ecosystems typically occur. Given these massive and widespread changes, the species has the potential to provide considerable insight into the evolutionary and ecological effects of human impacts on aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Bangladesh, a developing country, is experiencing a rapid increase in its energy requirements due to its consistent economic growth in recent years. However, little is known about the economic contributions of access to electricity (AE), energy consumption (EC), and population growth (PG). In this study, the asymmetrical connection among PG, EC and electricity accessibility in Bangladesh is examined over a span of 36 years, from 1985 to 2021. The study used non‐linear ARDL cointegration methods as well as Granger Causality. For robustness, this study used Fully Modified Ordinary Least Squares (FMOLS) and Canonical Cointegrating Regression (CCR). The results reveal that PG has a notable favourable impact on economic growth, and conversely, a declining population also leads to a substantial positive influence on economic growth. Both favourable and adverse fluctuations in electricity accessibility exhibit detrimental effects on long‐term economic growth. Over the course of time, enhancing power accessibility has contributed to the rise in economic growth. Unfavourable EC shocks exhibit a meaningfully positive influence on economic growth in Bangladesh. Nevertheless, the positive EC shock does not have a notable impact on long‐term economic growth. The data also demonstrate bidirectional causality between PG and economic growth and EC and economic growth (EG). There is also a unidirectional causal link between PG and AE and EC and PG. The findings have significant policy ramifications for those in charge of making decisions in Bangladesh that would help the country achieve its economic goals by bolstering its energy industry. [ABSTRACT FROM AUTHOR]

Dynamical systems are one of the interesting concepts where iteration algorithms and chaos can be considered together. In iteration algorithms, one of the basic concepts of fixed point theory, it is well known that the behavior of the iteration mechanism is chaotic if the original transformation is taken as chaotic. One of the natural ways to transform a chaotic system into a dynamical system is through control mechanisms. In this paper, we first consider an iteration class defined on Banach spaces, which is prominent in the literature in terms of both speed and convergence rate. Then, we consider the transformation constituting the iteration class as chaotic and obtain the stability and unstability behaviors of the iterations according to the operator norm by using Gâteaux and Fréchet derivatives representing the direction‐dependent derivative. In this way, we aimed to obtain the chaos control intervals obtained with functions in real space with the help of operators in Banach spaces. Using the operator norm obtained with the Fréchet derivative, we derive interesting dynamical system intervals from a chaotic system with parameter variables of iteration algorithms. It is noteworthy that the parameter variables of the studied iteration classes are the same in some transformation classes. In addition, analytical proofs are followed by computer simulations of parameter‐dependent control intervals considering the logistic operator with a chaotic structure. At the same time, the periodic behavior of the iteration algorithms used in our study is illustrated by the Lyapunov exponent with parameter‐dependent control intervals according to operator norm. Finally, as a real‐life problem, it has been shown that the chaos of the logistic population growth model with dynamic features can be controlled by chaos control mechanisms established by fixed point iteration methods. [ABSTRACT FROM AUTHOR]

Road salt (NaCl) is the most common deicer used to melt snow and ice from roadways in cold climates, but its use results in runoff of sodium and chloride ions into sewers and into soil and freshwater ecosystems. Road salt causes harmful effects on wetland habitats, which host an abundance of macroinvertebrate species. Alternatives to road salt, such as beet juice, are commercially available, but their impact on invertebrates is less well studied. We examined the impact of road salt alternatives on four invertebrate species (Daphnia pulex, Eisenia fetida, Heterocypris sp., and Culicoides sp. larvae), some of which come from a naturally brackish area. Our expectation was that road salt alternatives (beet salt, molasses, pickle juice, and sand) would be less toxic to the animals than traditional road salt. This study comprised two experiments: the first exposed individuals of the four invertebrate species to road salt alternatives, and the second exposed the invertebrates to a range of road salt concentrations. Only individuals of D. pulex were negatively impacted by road salt. The other invertebrates were not significantly affected by any salt alternative, demonstrating interspecific differences in response to salt. Species found in naturally salty environments were more tolerant of both road salt and alternatives. This research shows species‐ and habitat‐specific responses to road salt alternatives, which has implications for municipalities looking to salt roads without negatively impacting freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Thermal acclimation can provide an essential buffer against heat stress for host populations, while acting simultaneously on various life‐history traits that determine population growth. In turn, the ability of a pathogen to invade a host population is intimately linked to these changes via the supply of new susceptible hosts, as well as the impact of warming on its immediate infection dynamics. Acclimation therefore has consequences for hosts and pathogens that extend beyond simply coping with heat stress—governing both population growth trajectories and, as a result, an inherent propensity for a disease outbreak to occur. The impact of thermal acclimation on heat tolerances, however, is rarely considered simultaneously with metrics of both host and pathogen population growth, and ultimately fitness. Using the host Daphnia magna and its bacterial pathogen, we investigated how thermal acclimation impacts host and pathogen performance at both the individual and population scales. We first tested the effect of maternal and direct thermal acclimation on the life‐history traits of infected and uninfected individuals, such as heat tolerance, fecundity, and lifespan, as well as pathogen infection success and spore production. We then predicted the effects of each acclimation treatment on rates of host and pathogen population increase by deriving a host's intrinsic growth rate (rm) and a pathogen's basic reproductive number (R0). We found that direct acclimation to warming enhanced a host's heat tolerance and rate of population growth, despite a decline in life‐history traits such as lifetime fecundity and lifespan. In contrast, pathogen performance was consistently worse under warming, with within‐host pathogen success, and ultimately the potential for disease spread, severely hampered at higher temperatures. Our results suggest that hosts could benefit more from warming than their pathogens, but only by linking multiple individual traits to population processes can the full impact of higher temperatures on host and pathogen population dynamics be realised. [ABSTRACT FROM AUTHOR]

The growth trajectories of trees are not fully understood due to their long life span. We characterized the population dynamics of the canopy tree Castanopsis cuspidata (Thunb.) Schottky in a Japanese warm‐temperate forest over 49 years (1966–2015). Our study was initiated approximately 50 years after our study site was clear‐cut. The forest had a closed canopy for the first 23 years of the study. Strong typhoons in 1991 and 1993 seriously damaged the forest, and since then the forest has been recovering from these disturbances. The diameter distribution of this species was bell‐shaped in 1966, suggesting that the trees emerged simultaneously after the clear‐cut in the 1910s, and the recruitment of trees has remained unchanged since then. The lack of recruitment of C. cuspidata before the typhoon disturbance supports this conclusion. Assuming that the C. cuspidata trees in 1966 were cohorts that were established soon after the clear‐cut, the size differences reflect differences in growth rate, with small trees corresponding to slow growers and large trees corresponding to fast growers. Before the typhoon, slow growers had low survival, and the mortality rate of fast growers was low. Many fast growers were uprooted or snapped by strong winds by the typhoons. However, their mortality rate did not differ from that of slow growers because many slow growers were killed by large fallen trees. The growth of some slow‐growing survivors increased after the typhoon, which allowed them to rapidly reach the canopy. Therefore, the typhoon altered the distribution of canopy trees among slow and fast growers. Survivors experienced faster growth than trees that died during the census period, suggesting that growth rate provides a robust indicator of future survival. Before the typhoon, the survival of fast growers was higher than that of slow growers. This suggests that fast growers disproportionally contribute to reproduction compared with slow growers. However, no recruited tree was observed in this subperiod, suggesting that fast growers made no contribution to reproduction. Fast growers might not play a more significant demographic role than slow growers in this species. [ABSTRACT FROM AUTHOR]

In 2001 and 2002, 52 elk (Cervus canadensis; 21 males, 31 females), originally obtained from Elk Island National Park, Alberta, Canada, were transported and released into Cataloochee Valley in the northeastern portion of Great Smoky Mountains National Park (GRSM, Park), North Carolina, USA. The annual population growth rate (λ) was negative (0.996, 95% CI = 0.945–1.047) and predation by black bears (Ursus americanus) on elk calves was identified as an important determinant of population growth. From 2006 to 2008, 49 bears from the primary elk calving area (i.e., Cataloochee Valley) were trapped and translocated about 70 km to the southwestern portion of the Park just prior to elk calving. Per capita recruitment (i.e., the number of calves produced per adult female that survive to 1 year of age) increased from 0.306 prior to bear translocation (2001–2005) to 0.544 during years when bears were translocated (2006–2008) and λ increased to 1.118 (95% CI = 1.096–1.140). Our objective was to determine whether per capita calf recruitment rates after bear removal (2009–2019) at Cataloochee were similar to the higher rates estimated during bear removal (i.e., long‐term response) or if they returned to rates before bear removal (i.e., short‐term response), and how those rates compared with recruitment from portions of our study area where bears were not relocated. We documented 419 potential elk calving events and monitored 129 yearling and adult elk from 2001 to 2019. Known‐fate models based on radio‐telemetry and observational data supported calf recruitment returning to pre‐2006 levels at Cataloochee (short‐term response); recruitment of Cataloochee elk before and after bear relocation was lower (0.184) than during bear relocation (0.492). Recruitment rates of elk outside the removal area during the bear relocation period (0.478) were similar to before and after rates (0.420). In the Cataloochee Valley, cause‐specific annual calf mortality rates due to predation by bears were 0.319 before, 0.120 during, and 0.306 after bear relocation. In contrast, the cause‐specific annual mortality rate of calves in areas where bears were not relocated was 0.033 after the bear relocation period, with no bear predation on calves before or during bear relocation. The mean annual population growth rate for all monitored elk was 1.062 (95% CI = 0.979–1.140) after bear relocation based on the recruitment and survival data. Even though the effects of bear removal were temporary, the relocations were effective in achieving a short‐term increase in elk recruitment, which was important for the reintroduction program given that the elk population was small and vulnerable to extirpation. [ABSTRACT FROM AUTHOR]

Population growth is the sum of survival and recruitment, and knowledge of these two vital rates is crucial for understanding population dynamics. Moreover, animal populations often contain varying number of transient (i.e. nonresident) individuals that do not contribute to these rates but may bias their estimates. The widely used Pradel (1996, Biometrics, 52: 703) survival‐recruitment model for capture–mark–recapture data is only able to handle resident individuals on a fixed study area across a particular study period. Yet, numerous capture–mark–recapture data sets, from a wide range of taxa, feature transient individuals. The most widespread sources of avian demographic data, based on citizen science projects, feature both transient individuals and changes in the study area over time.We present an extension of the Pradel model that accounts for the presence of transient individuals and changes in the study area. In contrast to known extensions of the Cormack–Jolly–Seber models in which transients are modelled as a proportion of newly captured individuals, our novel approach models transient individuals as a proportion of all birds captured. In addition, we present a new simple way to visualize the interlinkage of the vital rates produced by our extended Pradel model.We demonstrate utilization of the model using capture–mark–recapture data collected by a constant‐effort mist‐netting citizen science programme in the Czech Republic, presenting demographic rates of two species with different population dynamics. To demonstrate the newly achieved ability to analyse the phenomenon of transience, we show the differences in transience and its temporal trends between wet and dry habitats.Removing the limitations of the Pradel model opens up new potential for much wider range of applications. Furthermore, our novel parametrization of transients as a proportion of all birds captured facilitates biological interpretation of the transience parameter and the study of transience as a biological phenomenon. Calculating all demographic parameters in a single model also opens up a unique possibility to take into account their correlated error distributions in follow‐up analyses. Our model can be further extended in several ways and can serve as a basic building block in a wide range of demographic analyses. [ABSTRACT FROM AUTHOR]

Population growth exerts an impact on both sides of the local government accounting ledger—expenditure and revenue. Despite this fact, the vast scholarly literature on local government finance has been myopically focussed on expenditure functions. This apparent neglect to also consider the revenue side of the ledger is problematic because many regulators across the globe have exhorted local governments to pursue growth according to the assumption that it will promote fiscal health. In this article, we first set out a number of propositions that combine to cast some doubt on the common wisdom dispensed by local government policy‐makers. Following this, we empirically explore the effects of population growth on revenue by making recourse to a comprehensive 10‐year panel of revenue and population data. We conclude our work with some important public policy recommendations arising from the need to mitigate the prima facie surprising results that we obtain. Points for practitioners: Public policy architects have exhorted local governments to pursue population growth as a way to mitigate financial sustainability problems. However, this advice has been based on assumptions only and not subjected to empirical investigation.Econometric estimations demonstrate a negative association between unit revenue and population growth which means that the policy advice is likely to exacerbate financial distress.A number of changes could be made to local government taxation, pricing, and grants that would mitigate the deleterious effects of population growth on financial sustainability. [ABSTRACT FROM AUTHOR]

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Herbivores shape plant invasions through impacts on demography and dispersal, yet only demographic mechanisms are well understood. Although herbivores negatively impact demography by definition, they can affect dispersal either negatively (e.g., seed consumption), or positively (e.g., caching). Exploring the nuances of how herbivores influence spatial spread will improve the forecasting of plant movement on the landscape. Here, we aim to understand how herbivores impact how fast plant populations spread through varying impacts on plant demography and dispersal. We strive to determine whether, and under what conditions, we see net positive effects of herbivores, in order to find scenarios where herbivores can help to promote spread. We draw on classic invasion theory to develop a stage-structured integrodifference equation model that incorporates herbivore impacts on plant demography and dispersal. We simulate seven herbivore "syndromes" (combinations of demographic and/or dispersal effects) drawn from the literature to understand how increasing herbivore pressure alters plant spreading speed. We find that herbivores with solely negative effects on plant demography or dispersal always slow plant spreading speed, and that the speed slows monotonically as herbivore pressure increases. However, we also find that plant spreading speed can be hump shaped with respect to herbivore pressure: plants spread faster in the presence of herbivores (for low herbivore pressure) and then slower (for high herbivore pressure). This result is robust, occurring across all syndromes in which herbivores have a positive effect on plant dispersal, and is a sign that the positive effects of herbivores on dispersal can outweigh their negative effects on demography. For all syndromes we find that sufficiently high herbivore pressure results in population collapse. Thus, our findings show that herbivores can speed up or slow down plant spread. These insights allow for a greater understanding of how to slow invasions, facilitate native species recolonization, and shape range shifts with global change. [ABSTRACT FROM AUTHOR]

This study examines the effect of population growth on aggregate domestic investments in 45 Sub-Saharan African (SSA) countries over the period 2000-2020. It applies the QuantileMethod ofMoments with fixed effects (i.e., MM-QR), which has the ability to identify both negative and positive effects while controlling for trade, HIV/AIDS prevalence, and economic growth. The findings show that SSA's rapid population growth has a positive and statistically significant effect on aggregate domestic investments. Findings from this study show that an increase in population growth in the 10th to 60th quantiles is associated with an increase of domestic investment in SSA. This suggests that, as the population grows in SSA, it generates demand for domestic investments such as healthcare services, education, and other social services. Our findings also show that trade is positive and significant across all quantiles (10th to 90th). We find evidence that disease risks, such as the prevalence of HIV/AIDS, slowed the increase in domestic investment in the region across all quantiles (10th to 90th). We conclude by arguing that, since SSA's population growth will double in the near future, the region is bound to become world's next investment hub. In order to enable long-term domestic investments in the region, future policy options should take the challenges of population growth into account. [ABSTRACT FROM AUTHOR]

In light of rapidly expanding road networks worldwide, there is increasing global awareness of the growing amount of mammalian roadkill. However, the ways in which road mortality affects the population dynamics of different species remains largely unclear. We aimed to categorise the demographic parameters in mammalian populations around the world that are directly or indirectly affected by road mortality, as well as identify the most effective study designs for quantifying population‐level consequences of road mortality. We conducted a comprehensive systematic review to synthesise literature published between 2000 and 2021 and out of 11,238 unique studies returned, 83 studies were retained comprising 69 mammalian species and 150 populations. A bias towards research‐intensive countries and larger mammals was apparent. Although searches were conducted in five languages, all studies meeting the inclusion criteria were in English. Relatively few studies (13.3%) provided relevant demographic context to roadkill figures, hampering understanding of the impacts on population persistence. We categorised five direct demographic parameters affected by road mortality: sex‐ and age‐biased mortality, the percentage of a population killed on roads per year (values up to 50% were reported), the contribution of roadkill to total mortality rates (up to 80%), and roadkill during inter‐patch or long‐distance movements. Female‐biased mortality may be more prevalent than previously recognised and is likely to be critical to population dynamics. Roadkill was the greatest source of mortality for 28% of studied populations and both additive and compensatory mechanisms to roadkill were found to occur, bringing varied challenges to conservation around roads. In addition, intra‐specific population differences in demographic effects of road mortality were common. This highlights that the relative importance of road mortality is likely to be context specific as the road configuration and habitat quality surrounding a population can vary. Road ecology studies that collect data on key life parameters, such as age/stage/sex‐specific survival and dispersal success, and that use a combination of methods are critical in understanding long‐term impacts. Quantifying the demographic impacts of road mortality is an important yet complex consideration for proactive road management. [ABSTRACT FROM AUTHOR]

Background: Ghana has witnessed rapid urban population growth over the past decades, which has led to vast environmental, settlement, human, and ecological issues. It is therefore extremely important to examine the factors that influence urban population growth in Ghana to provide policy directions for policymakers. Objectives: The article examines the impact of financial inclusion on urban population growth using three different measures of financial inclusion. Methods: We applied the autoregressive distributed lag model (ARDL) to historical time‐series data covering the period of 1960 to 2020. Results: The estimates from the ARDL model show that financial inclusion exerts a positive effect on urban population growth. Specifically, the findings confirm that financial knowledge, usage, and availability of financial services contribute significantly to urban population growth over time. Conclusion: The findings in this study suggest that government and financial institutions should utilize various channels to increase financial knowledge, usage and availability of financial services among individuals living in deprived areas where there are a limited number of financial institutions. [ABSTRACT FROM AUTHOR]

Carrying capacity has multiple definitions, but nowadays, it is mainly referred to as the maximum number of individuals of a particular species sustained by the environment. We examined whether multiple populations of two flour beetle species grown under controlled laboratory conditions reach similar asymptotic population sizes when provided with similar amounts of food resources. We demonstrate that the variation in the asymptotic population sizes was considerably larger than that of the initial food resources and that the latter had no significant effect on the former. Our results experimentally contribute to past literature criticizing the carrying capacity concept, demonstrating that there is no single carrying capacity even under strict laboratory conditions. Therefore, we should not expect to often find "carrying capacities" in nature, where resources fluctuate over time, and interspecific interactions are ubiquitous. We suggest that the classic meaning of carrying capacity should be revisited or saved chiefly for didactic purposes. Research Highlights: Carrying capacity is the number of individuals a habitat can support. A study of two flour beetles species challenges this concept. Even when given similar amounts of food, the population sizes varied. The study suggests caution when applying this concept. [ABSTRACT FROM AUTHOR]

The human population is projected to increase by 2.4 billion to 2100, endangering, for example, food security and biodiversity. Population growth depends strongly on fertility level, lowering of which is often assumed to depend on economic growth. Here we test this hypothesis using data from 136 developing countries, 1970–2014. We formed four country groups at different initial economy, and used graphical analyses, with estimates of variation. Falling fertility rates 1970–2000 showed little or no association with economy (GDP or household consumption). Fertility decreased regardless of whether the economy grew, was stagnant, or declined. But falling fertility was closely associated with increasing use of modern contraception, which was largely independent of changes in economy. Fertility decline hence was not caused by economic development, but followed contraceptive use. Family planning programs, with advice on family size and modern contraception, offer promising routes to sustainably low fertility where it has not yet been achieved. [ABSTRACT FROM AUTHOR]

Headstarting is a conservation tool that assumes raising turtles in protected ex situ environments to larger body sizes, then releasing them back into the wild, increases their survivorship compared to wild, non‐headstarted turtles. Our goal was to quantitatively test this fundamental assumption by comparing somatic growth and survivorship among 3 age classes of headstarted juvenile wood turtles (Glyptemys insculpta) monitored for 3 years (2016–2018) in Ontario, Canada. Our age classes were turtles headstarted for 2 years (n = 15), turtles headstarted for 1 year (n = 30), and turtles incubated and hatched ex situ, then released (i.e., no headstarting; hatchlings, n = 30). Both age classes of headstarted turtles were radio‐tracked for 1 year after release. We released hatchlings in August and radio‐tracked them for 1 month. All cohorts exhibited positive somatic growth after release. One‐month post‐release survival of hatchlings was 70%. Turtles headstarted for 2 years had slightly higher 1‐year post‐release survivorship (67%) than turtles headstarted for 1 year (47%), but there was little to no evidence for a difference (P = 0.17). Modeling these survivorship results with real‐life constraints of only 100 hatchlings available for headstarting each year (biological constraint from source population), and a 100‐turtle capacity in our headstarting facility (economic constraint), projected similar population growth in 2‐year and 1‐year headstarting programs. When removing the 100‐turtle facility limit, the 2‐year program projected higher population growth but required space for 200 turtles in the headstarting facility, which may not be feasible for many programs. Our results support the fundamental assumption that headstarting increases survivorship, but we observed diminishing returns if headstarting was increased for longer than 1 year. Given the growing number of turtle headstarting projects globally, our study provides data that can aid in establishing cost‐ and resource‐effective best practices. [ABSTRACT FROM AUTHOR]

Summary: The stochastic growth rate describes long‐run growth of a population that lives in a fluctuating environment. Perturbation analysis of the stochastic growth rate provides crucial information for population managers, ecologists and evolutionary biologists. This analysis quantifies the response of the stochastic growth rate to changes in demographic parameters. A form of this analysis deals with changes that only occur in some environmental states. Caswell put forth two conjectures about environment‐specific perturbations of the stochastic growth rate. The conjectures link the stationary distribution of the stochastic environmental process with the magnitude of some environment‐specific perturbations. This note disproves one conjecture and proves the other. [ABSTRACT FROM AUTHOR]

Competition is among the most important factors regulating plant population and community dynamics, but we know little about how different vital rates respond to competition and jointly determine population growth and species coexistence. We conducted a field experiment and parameterised integral projection models to model the population growth of 14 herbaceous plant species in the absence and presence of neighbours across an elevation gradient (284 interspecific pairs). We found that suppressed individual growth and seedling establishment contributed the most to competition‐induced declines in population growth, although vital rate contributions varied greatly between species and with elevation. In contrast, size‐specific survival and flowering probability and seed production were frequently enhanced under competition. These compensatory vital rate responses were nearly ubiquitous (occurred in 92% of species pairs) and significantly reduced niche overlap and stabilised coexistence. Our study highlights the importance of demographic processes for regulating population and community dynamics, which has often been neglected by classic coexistence theories. [ABSTRACT FROM AUTHOR]

Key Takeaways: Des Moines Water Works' (DMWW's) source water faces significant water quality challenges from decades of agricultural nutrient pollution in Iowa. Lackluster results in regulating nutrient pollution, along with population growth and effects of climate change, add urgency to DMWW's drive to improve source water quality. To protect its source water, DMWW has collaborated with groups outside of its typical scope, building relationships with those who have the same values and vision. [ABSTRACT FROM AUTHOR]

Recent declines in eastern wild turkeys (Meleagris gallopavo silvestris) have prompted increased interest in management and research of this important game species. However, the mechanisms underlying these declines are unclear, leaving uncertainty in how best to manage this species. Foundational to effective management of wildlife species is understanding the biotic and abiotic factors that influence demographic parameters and the contribution of vital rates to population growth. Our objectives for this study were to (1) conduct a literature review to collect all published vital rates for eastern wild turkey over the last 50 years, (2) perform a scoping review of the biotic and abiotic factors that have been studied relative to wild turkey vital rates and highlight areas that require additional research, and (3) use the published vital rates to populate a life‐stage simulation analysis (LSA) and identify the vital rates that make the greatest contribution to population growth. Based on published vital rates for eastern wild turkey, we estimated a mean asymptotic population growth rate (λ) of 0.91 (95% CI = 0.71, 1.12). Vital rates associated with after‐second‐year (ASY) females were most influential in determining population growth. Survival of ASY females had the greatest elasticity (0.53), while reproduction of ASY females had lower elasticity (0.21), but high process variance, causing it to explain a greater proportion of variance in λ. Our scoping review found that most research has focused on the effects of habitat characteristics at nest sites and the direct effects of harvest on adult survival, while research on topics such as disease, weather, predators, or anthropogenic activity on vital rates has received less attention. We recommend that future research take a more mechanistic approach to understanding variation in wild turkey vital rates as this will assist managers in determining the most appropriate management approach. [ABSTRACT FROM AUTHOR]

Apple replant disease (ARD) is common to all major apple‐growing regions in the world. It occurs when new apple trees are replanted on sites where previously the same or closely related crop species were grown. Biotic (fungi, bacteria and nematodes) and abiotic soil factors (poor soil structure, nutrition) contribute to the development and severity of ARD. However, the aetiology of ARD and effects on higher trophic levels are still unknown. In that sense, Collembola might play an important role, since they are one of the dominant mesofauna groups in many soils. They act as decomposer, fungivores and predators, representing different trophic levels in soil food webs. Therefore, any effect of ARD on the occurrence of Collembola could have ecological impacts on the soil quality and health. Here, we examined the colonization behaviour of two Collembolan species, Folsomia candida and Sinella curviseta, in choice tests and population growth tests using Apple Replant Diseased soil (ARD) and non‐ARD soil samples from different field sites and standardized laboratory bioassays. Additionally, Collembola behaviour was quantified by continuous video observations to investigate short‐term behavioural changes. Results showed that both Collembolan species significantly preferred colonization of the non‐ARD soils compared with ARD soils, independent of the origin of the soil samples or specific disinfection treatments. Moreover, the detailed video analysis of the foraging behaviour indicates rapid colonization of soil samples and low dispersal rates. Most likely, volatile compounds and to a lesser extent feeding stimulants play a vital role for the colonization process for both Collembolan species. Finally, results showed negative effects of ARD on population growth of both Collembolan species already after an 8‐week period, implying strong nutritional deficiencies in ARD affected soils. The hypothesis that ARD causing microorganisms directly affected orientation, colonization and population development of Collembola is discussed. [ABSTRACT FROM AUTHOR]

Fishers (Pekania pennanti) are a forest‐dependent carnivore of conservation concern in British Columbia, Canada. Ecological, spatial, and genetic evidence suggests that there are 2 distinct populations (Boreal and Columbian) that occur in forests at low to moderate elevations in the boreal and central interior regions of the province. In British Columbia, fishers occur at low densities relative to other parts of their range in North America, are trapped for their fur, and are sensitive to habitat change. Despite these factors, little demographic information exists to assist with management decisions for these populations. We collated and analyzed survival and reproductive data from 100 radio‐tagged fishers from 5 independent studies conducted between 1990 and 2012 in British Columbia: 2 in the Boreal population, and 3 in the Columbian population. We also collated litter size data from 1 den box study and a translocation project of fishers from the Columbian population. Annual survival rates were not significantly different between the populations or between males and females; however, adult survival rates were higher than subadults (0.79 and 0.63, respectively). Subadult females had significantly lower survival rates than other sex or age classes. Reproductive rates were significantly different between the 2 populations (denning rate = 0.54 [Columbian], 0.82 [Boreal]; x¯ $\bar{x}$ litter size = 1.7 [Columbian], 2.6 [Boreal]). These differences resulted in net reproductive rates in the Columbian population that were less than half of those in the Boreal population (0.92 kits/reproductive season compared to 2.13, respectively). Population growth rates suggest that the Columbian population may have been declining during the studies, whereas the Boreal population may have been increasing (0.96 compared to 1.20). Consequently, we suggest that focused and intensive habitat and population management for fishers are needed in British Columbia to ensure population sustainability, particularly for the Columbian population. [ABSTRACT FROM AUTHOR]

Key Takeaways: Of 301 analyzed utilities in North Carolina, 51% reported operating revenues less than operating expenditures—operating ratios (ORs) less than 1. Affordability burden and OR were both affected by utilities' respective population size, population growth or loss rate, and median household income. Annual supplemental funding would be needed to provide all 301 utilities with sufficient revenue to cover operating expenses to ensure ORs are greater than 1. When evaluating consolidation of the utilities into a collective entity, the cumulative revenue of the 301 utilities well exceeded the sum of operating expenses. [ABSTRACT FROM AUTHOR]

Integrated population models (IPMs) combine population counts with demographic data to improve the precision of estimates of population size and demographic rates. IPMs can also provide information on demographic parameters for which data are lacking (e.g., immigration) if other sufficient information is available. IPMs often use demographic data from one sex, usually females, implicitly assuming the chosen sex adequately represents the species' life history; for highly size‐dimorphic raptors, that assumption may not hold true. We developed a two‐sex IPM for a New Mexico population of the highly size‐dimorphic Cooper's hawk (Accipiter cooperii) from 2011 to 2020 and compared estimates of life history characteristics between sexes. Because we had data to directly estimate sex‐ and age‐specific probabilities of breeding, fecundity, survival, brood sex ratios, and emigration rates, we could indirectly estimate age‐specific immigration rates for both sexes. Our two‐sex IPM revealed that population growth was most strongly associated with increased immigration and decreased first‐year (FY) emigration in females and with after‐first‐year (AFY) survival in males. Most males that were recruited as new breeders in our study area were AFY residents, whereas most female recruits were AFY immigrants. All females that fledged in our study area and survived until their first breeding season bred in their first year, whereas only 3% of surviving FY males bred. We found evidence of density dependence in the survival of AFY males (r = −0.11, 95% credible interval = −0.36 to −0.03) and in AFY female immigration (r = −0.17, 95% credible interval = −0.27 to −0.12). Our findings reveal that male and female Cooper's hawks differ in their response to population density, and in how they contribute to population growth. Thus, sexual differences in vital rates can be an important consideration in raptor population models. [ABSTRACT FROM AUTHOR]

Sensitivity analysis in ecology and evolution is a valuable guide to rank demographic parameters depending on their relevance to population growth. Here, we propose a method to make the sensitivity analysis of population growth for matrix models solely classified by stage more fine‐grained by considering the effect of age‐specific parameters. The method applies to stable population growth, the stochastic growth rate, and transient growth. The method yields expressions for the sensitivity of stable population growth to age‐specific survival and fecundity from which general properties are derived about the pattern of age‐specific selective forces molding senescence in stage‐classified populations. [ABSTRACT FROM AUTHOR]

Identifying successful management strategies for long‐lived species is challenging, especially in fluctuating environments, because the response of individual vital rates and overall growth rates to management action can vary over time. A demographic approach that isolates the impact of management and environment on individual vital rates, and assesses their importance for growth rate over time, can indicate whether and why a management strategy is successful.Here we take a demographic approach to assess the success of grazing management for the perennial grass Stipa pulchra, California's state grass and a focus on conservation efforts. We tracked S. pulchra populations in paired grazed and ungrazed plots over 6 years, which included a historic drought and an El Niño rain year, and calculated summary transition matrices for the main effects of year, grazing and year × grazing interaction for each site. We averaged these summary transition matrices to calculate population growth rates, λ, for the main effects of year, grazing and year × grazing and used life table response experiment (LTRE) analysis to compare how individual vital rates contributed to differences in λ between grazed and ungrazed plots over time.Overall we found that grazing was a successful management strategy; grazed populations maintained a positive average population growth rate whereas ungrazed populations declined. We found that grazing had a larger positive effect on growth rates in wet years than drought years. This was because grazed populations benefited from a greater contribution of adult growth immediately following the end of the drought compared with ungrazed populations and from adult survival thereafter.Synthesis and applications. Although Stipa pulchra is the focus of many management efforts, the use of grazing for management is contentious, and there have been few studies that take a demographic approach to understanding S. pulchra responses over time. Our results indicate that conservation and restoration efforts should move beyond recruitment to focus on adult growth and survival for overall population success. To this end, moderate grazing can be a successful strategy to maintain S. pulchra populations and is particularly important in wet years to promote plant growth. [ABSTRACT FROM AUTHOR]

Rare species serve important ecosystem functions, including community resilience to global change. Yet rare species are disappearing globally because of anthropogenic activities such as fire suppression. Prescribed burning is a widespread management approach that can reduce invasive plant presence, recycle nutrients, and restore species diversity. However, the effects of prescribed burning on rare plants are not well understood. We analyzed the population dynamics of 67 rare, native plant species in response to prescribed burning using the Chicago botanic garden's Plants of Concern dataset. This dataset includes rare plant populations concentrated in the northeast part of Illinois, and a few populations in Indiana and Wisconsin, United States. We evaluated the effects of burning by comparing the percent change in population size in the short‐term (1–2 years) and long‐term (3–4 years) after prescribed burning, to the percent change in population size not following burns. In a global model with all species, we did not detect the effects of burning on percent change in population size. In species‐level analyses, we detected burn effects for most species for which we had the statistical power to detect possible burn responses, although the direction of their responses was mixed. Five species responded consistently between short‐ and long‐term datasets, and four species had mixed responses, with most responding positively over the short‐term and negatively over the long‐term. We complemented this analysis with a literature review of fire responses for available species. Our literature review revealed more responses to burning than what we found from our analyses; however, most of this evidence does not compare burned and unburned populations directly and should be treated cautiously. Through community science monitoring efforts, we were able to compile one of the largest studies of burn effects on rare plants to date, but continued monitoring is necessary to fully evaluate how prescribed burning impacts rare plant species. [ABSTRACT FROM AUTHOR]

BACKGROUND: Agrotis ipsilon and A. segetum are major migratory pests of many crops in China, and frequent regional outbreaks cause severe yield losses. Use of food attractants is one of the most promising control methods against adult lepidoptera, notably through the attract‐and‐kill strategy. Chlorantraniliprole's acute toxicity and sublethal effects on both moths were evaluated. RESULTS: Chlorantraniliprole showed high activity against both adults of both species, with LC20 and LC50 values of 0.08 and 0.21 mg L−1 (A. ipsilon), and 0.14 and 0.51 mg L−1 (A. segetum). The fecundity, effective oviposition rate, and egg hatching rate of both species in dual‐sex exposure treatments were all significantly reduced compared with the control, and the population growth coefficients in the LC50♀ × LC50♂ treatments were only 0.32% (A. ipsilon) and 3.35% (A. segetum) that of the control. Furthermore, the flight distance was significantly suppressed from 6.67 km (control) to 0.01 km (LC50) for A. ipsilon, and from 7.39 km (control) to 0.78 km (LC50) for A. segetum. The proportions of robust‐ and medium‐flight individuals of A. ipsilon and A. segetum in exposure treatments were greatly reduced. CONCLUSIONS: Low lethal concentration exposures to chlorantraniliprole can drastically reduce the reproduction and flight performance of A. ipsilon and A. segetum, while inhibiting the production of offspring, suggesting chlorantraniliprole would be an excellent compound for use in combination with food attractants. Chlorantraniliprole has good potential for management of the two long‐range migratory pests tested using an attract‐and‐kill strategy. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In Northeast China, thrips have long been considered a secondary pest of soybean until recent years. No study has provided clear reports regarding the effects of temperature on the development and reproduction of Thrips flavus Schrank (Thysanoptera: Thripidae).Our aim was to study whether the population dynamics of T. flavus were affected by temperatures. Thus, the development, reproduction and growth of T. flavus populations reared on soybean leaves were studied at five different constant temperatures.The temperature and rate of development from eggs to adults were linearly related between 19 and 31°C. The developmental threshold temperature and effective accumulated temperature were 11.60°C and 273.89 degree‐days for the whole generation. The viability of adult survival decreased with the increase in temperature between 19 and 31°C.The value of life expectancy of females ranged from 7.47 days (at 31°C) to 16.66 days (at 22°C), while the life expectancy value of males ranged from 5.33 days (at 19 and 31°C) to 17.0 days (at 25°C). The mean fecundity per female was highest at 19°C, with 7.85 eggs/day. The intrinsic rate of increase was the highest (0.102) at 31°C.The results obtained indicate that temperature is a key factor associated with the development and reproduction of T. flavus on soybean. [ABSTRACT FROM AUTHOR]

Predicting the geographic range of species and their response to climatic variation and change are entwined goals in conservation and evolutionary ecology. Species distribution models (SDMs) are foundational in this effort and used to visualize the geographic range of species as the spatial representation of its realized niche. SDMs are also used to forecast range shifts under climate change, but often in the absence of empirical evidence that climate limits population growth. We explored the influence of climate on demography, seasonal migration, and the extent of the geographic range in song sparrows (Melospiza melodia), a species thought to display marked local adaptation to regional climate. To do so, we developed SDMs to predict the demographic and climate niches of migratory and resident song sparrows across our study area in western North America from California to Alaska, using 48 years of demographic data from a focal population in British Columbia and 1.2 million continental-scale citizen science observations. Spatial agreement of our demographic and climate niche models in the region of our focal population was strong (76%), supporting the hypothesis that demographic performance and the occurrence of seasonal migration varied predictably with climatic conditions. In contrast, agreement at the northern (58%) and southern (40%) extents of our study area was lower, as expected if the factors limiting population growth vary regionally. Our results support the hypothesis that local climate drives spatial variation in the occurrence of seasonal migration in song sparrows by limiting the fitness of year-round residents, and suggest that climate warming has favored range expansions and facilitated an upward shift in elevational range song sparrows that forgo seasonal migration. Our work highlights the potential role of seasonal migration in climate adaptation and limits on the reliability of climate niche models not validated with demographic data. [ABSTRACT FROM AUTHOR]

This study investigates the dynamic effect of economic uncertainty on public health expenditure in the Economic Community of West African States region. The investigation is motivated by the recent volatilities in the global economy in the face of increasing demand for adequate funding of health systems in the region, and the need to fill the existing gap in the literature. The study employs the panel autoregressive distributed lag model to express the theoretical relationship between public health expenditure per capita, economic uncertainty and population growth rate, and estimates the model parameters using the mean group and the pooled mean group estimators, after accounting for stationarity and cointegration. Results reveal that on the aggregate, economic uncertainty and population growth are significant determinants of per capita health spending in the long run. When the countries are disaggregated by income groups, evidence suggests that in low‐income countries, economic uncertainty is negatively associated with health spending in the short run, while a growing population reduces health spending per capita in the long run. In lower‐middle‐income countries, economic uncertainty increases health spending in the short run, but reduces it in the long run as uncertainty persists, while population growth negatively impacts health spending in the long run. We conclude that the dependence on public funding of the health system in the region appears unsustainable. Thus, health financing policies need to explore alternative funding mechanisms that entrench cost‐sharing between the public and private financiers. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used in ecology. In theory, SDMs capture (at least part of) species' ecological niches and can be used to make inferences about the distribution of suitable habitat for species of interest. Because habitat suitability is expected to influence population demography, SDMs have been used to estimate a variety of population parameters, from occurrence to genetic diversity. However, a critical look at the ability of SDMs to predict independent data across different aspects of population biology is lacking. Here, we systematically reviewed the literature, retrieving 201 studies that tested predictions from SDMs against independent assessments of occurrence, abundance, population performance, and genetic diversity. Although there is some support for the ability of SDMs to predict occurrence (~53% of studies depending on how support was assessed), the predictive performance of these models declines progressively from occurrence to abundance, to population mean fitness, to genetic diversity. At the same time, we observed higher success among studies that evaluated performance for single versus multiple species, pointing to a possible publication bias. Thus, the limited accuracy of SDMs reported here may reflect the best‐case scenario. We discuss the limitations of these models and provide specific recommendations for their use for different applications going forward. However, we emphasize that predictions from SDMs, especially when used to inform conservation decisions, should be treated as hypotheses to be tested with independent data rather than as stand‐ins for the population parameters we seek to know. [ABSTRACT FROM AUTHOR]

Climate change can impact plant fitness and population persistence directly through changing abiotic conditions and indirectly through its effects on species interactions. Pollination and seed predation are important biotic interactions that can impact plant fitness, but their impact on population growth rates relative to the role of direct climatic effects is unknown.We combined 13 years of experiments on pollen limitation of seed set and pre‐dispersal seed predation in Ipomopsis aggregata, a subalpine wildflower, with a long‐term demographic study that has documented declining population growth with earlier spring snowmelt date. We determined how pollen limitation and seed predation changed with snowmelt date over 21 years and incorporated those effects into an integral projection model to assess relative impacts of biotic factors on population growth.Both pollen limitation and the difference in stigma pollen load between pollen‐supplemented and control plants declined over years. Neither pollen limitation nor seed predation changed detectably with snowmelt date, suggesting an absence of indirect effects of that specific abiotic factor on these indices of biotic interactions. The projected biotic impacts of pollen limitation and seed predation on population growth rate were small compared to factors associated with snowmelt date. Providing full pollination would delay the projected date when earlier snowmelt will cause populations to fall below replacement by only 14 years.Synthesis. Full pollination and elimination of seed predation would not compensate for the strong detrimental effects of early snowmelt on population growth rate, which in I. aggregata appears driven largely by abiotic environmental factors. The reduction over two decades in pollen limitation also suggests that natural selection on floral traits may weaken with continued climate change. These results highlight the value of studying both abiotic factors and biotic interactions to understand how climate change will influence plant populations. [ABSTRACT FROM AUTHOR]

The composition of founding populations plays an important role in colonisation dynamics and can influence population growth during early stages of biological invasion. Specifically, founding populations with small propagules (i.e. low number of founders) are vulnerable to the Allee effect and have reduced likelihood of establishment compared to those with large propagules. The founding sex ratio can also impact establishment via its influence on mating success and offspring production.Our goal was to test the effects of propagule size and sex ratio on offspring production and annual population growth following introductions of a non‐native lizard species (Anolis sagrei). We manipulated propagule composition on nine small islands, then examined offspring production, population growth and survival rate of founders and their descendants encompassing three generations.By the third reproductive season, per capita offspring production was higher on islands seeded with a relatively large propagule size, but population growth was not associated with propagule size. Propagule sex ratio did not affect offspring production, but populations with a female‐biased propagule had positive growth, whereas those with a male‐biased propagule had negative growth in the first year. Populations were not affected by propagule sex ratio in subsequent years, possibly due to rapid shifts towards balanced (or slightly female biased) population sex ratios.Overall, we show that different components of population fitness have different responses to propagule size and sex ratio in ways that could affect early stages of biological invasion. Despite these effects, the short life span and high fecundity of A. sagrei likely helped small populations to overcome Allee effects and enabled all populations to successfully establish.Our rare experimental manipulation of propagule size and sex ratio can inform predictions of colonisation dynamics in response to different compositions of founding populations, which is critical in the context of population ecology and invasion dynamics. [ABSTRACT FROM AUTHOR]

The FATTY ACID DESATURASE 7 (FAD7) enzyme is widely conserved across many groups of plants and influences resistance to multiple stresses, including aphid infestation. In the model plant Arabidopsis thaliana (L.) Heynh. (Brassicaceae), a loss‐of‐function mutation in the FAD7 gene decreases population growth of a generalist herbivore, the green peach aphid (GPA), Myzus persicae (Sulzer) (Hemiptera: Aphididae). This study used multiple bioassay designs to further characterize the effects of a fad7 mutant on the GPA, and also to determine whether fad7 impacts a specialist herbivore, the cabbage aphid (CA), Brevicoryne brassicae L. (Hemiptera: Aphididae). In choice assays, when presented with wild‐type A. thaliana (Col‐0) or fad7, neither GPA nor CA showed a preference between genotypes within 48 h. In no‐choice assays the fad7 mutation decreased the overall population growth of GPA, with significant differences in juvenile production occurring as early as 48 h after infestation. In contrast, CA showed comparable population growth on fad7 and Col‐0 at all time points, from 24 to 144 h (6 days). No‐choice assays also demonstrated that the fad7 mutation increased GPA development time and reduced fecundity but did not influence the mortality rates of adults or juveniles, or the weight of newly emerged adults reared on fad7. These results indicate that aphid resistance in the fad7 mutant is species‐specific, and that it impacts the population growth of GPA solely through antibiosis, decreasing adult fecundity and increasing juvenile development time. [ABSTRACT FROM AUTHOR]

Age‐ and sex‐specific survival rates are essential for understanding animal population dynamics and discerning environmental influences on population parameters. To date, little research has been done on age‐ and sex‐specific survival of the Gunnison's prairie dog (Cynomys gunnisoni), a colonial ground‐dwelling squirrel inhabiting the sagebrush ecosystem of the southwestern United States. To discern impacts of the year of study, age, sex, and reproductive status on survival, we conducted a capture‐mark‐recapture analysis on a previously collected long‐term dataset of a population of Gunnison's prairie dogs (n = 2508) from 1989 to 1995. We implemented two models: age‐cohort Cormack–Jolly–Seber (CJS) models (to examine survival by age, sex, and year) and multistate mark‐recapture models (to analyze survival by age and year, as well as breeding status). Females had higher apparent survival than males. Yearlings had a low apparent survival rate (0.288 ± 0.022, [±SE]) compared to juveniles (0.461 ± 0.019) and adults (0.482 ± 0.055). Less than 50% (48.0 ± 2.7) of female yearlings successfully weaned litters each year. Yearling survival rate was lower than other highly social prairie dog species that do not reproduce as yearlings, suggesting that there may be a cost to reproduction. We also constructed a postbreeding matrix population model and associated elasticity analysis, which indicated that the reproductive output of yearlings was the most significant potential driver of population growth. Our findings provide more nuanced estimates for age‐ and sex‐specific survival in this species than were previously available and also more broadly inform linkages between demography and sociality in prairie dogs. [ABSTRACT FROM AUTHOR]

The distribution of disease vectors such as mosquitoes is changing. Climate change, invasions and vector control strategies all alter the distribution and abundance of mosquitoes. When disease vectors undergo a range shift, so do disease burdens. Predicting such shifts is a priority to adequately prepare for disease control. Accurate predictions of distributional changes depend on how factors such as temperature and competition affect mosquito life‐history traits, particularly body size and reproduction. Direct estimates of both body size and reproduction in mosquitoes are logistically challenging and time‐consuming, so the field has long relied upon linear (isometric) conversions between wing length (a convenient proxy of size) and reproductive output. These linear transformations underlie most models projecting species' distributions and competitive interactions between native and invasive disease vectors. Using a series of meta‐analyses, we show that the relationship between wing length and fecundity are nonlinear (hyperallometric) for most mosquito species. We show that whilst most models ignore reproductive hyperallometry (with respect to wing length), doing so introduces systematic biases into estimates of population growth. In particular, failing to account for reproductive hyperallometry overestimates the effects of temperature and underestimates the effects of competition. Assuming isometry also increases the potential to misestimate the efficacy of vector control strategies by underestimating the contribution of larger females in population replenishment. Finally, failing to account for reproductive hyperallometry and variation in body size can lead to qualitative errors via the counter‐intuitive effects of Jensen's inequality. For example, if mean sizes decrease, but variance increases, then reproductive outputs may actually increase. We suggest that future disease vector models incorporate hyperallometric relationships to more accurately predict changes in mosquito distribution in response to global change. [ABSTRACT FROM AUTHOR]

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Summary: Coincident with a decade of introduced predator suppression, there was an increase in populations of a range of native mammals at the Royal Botanic Gardens Victoria (Cranbourne). A small, regionally significant population of the Black Wallaby (Wallabia bicolor) grew exponentially from an estimated 0.6 individuals km−2 in 2001 to more than 70 km−2 in 2013. The measured mean annual instantaneous rate of increase derived from a regular spotlight survey was ˜0.37 and extrapolates to a doubling of the population approximately every 2 years. There was little indication that growth was abating as the population increased. Modelling predicted that in the absence of a decline in fertility or natural increase in mortality one third of the population would need to be shed annually to moderate or reverse growth and allow vegetation communities and small mammal habitats to recover. [ABSTRACT FROM AUTHOR]

Key Takeaways: Urban water systems and public well‐being are threatened by factors that include aging infrastructure, population growth and density, and conditions related to climate change. Floods and droughts have been particularly hard on urban areas, with short‐ and long‐term effects running the gamut of environmental, human (physical and emotional), and economic devastation. Cities and organizations around the world are devising innovative ways to achieve water resilience; more can be done through targeted research to raise awareness and understanding. [ABSTRACT FROM AUTHOR]

With ongoing climate change, populations are expected to exhibit shifts in demographic performance that will alter where a species can persist. This presents unique challenges for managing plant populations and may require ongoing interventions, including in situ management or introduction into new locations. However, few studies have examined how climate change may affect plant demographic performance for a suite of species, or how effective management actions could be in mitigating climate change effects. Over the course of two experiments spanning 6 yr and four sites across a latitudinal gradient in the Pacific Northwest, United States, we manipulated temperature, precipitation, and disturbance intensity, and quantified effects on the demography of eight native annual prairie species. Each year we planted seeds and monitored germination, survival, and reproduction. We found that disturbance strongly influenced demographic performance and that seven of the eight species had increasingly poor performance with warmer conditions. Across species and sites, we observed 11% recruitment (the proportion of seeds planted that survived to reproduction) following high disturbance, but just 3.9% and 2.3% under intermediate and low disturbance, respectively. Moreover, mean seed production following high disturbance was often more than tenfold greater than under intermediate and low disturbance. Importantly, most species exhibited precipitous declines in their population growth rates (λ) under warmer‐than‐ambient experimental conditions and may require more frequent disturbance intervention to sustain populations. Aristida oligantha, a C4 grass, was the only species to have λ increase with warmer conditions. These results suggest that rising temperatures may cause many native annual plant species to decline, highlighting the urgency for adaptive management practices that facilitate their restoration or introduction to newly suitable locations. Frequent and intense disturbances are critical to reduce competitors and promote native annuals' persistence, but even such efforts may prove futile under future climate regimes. [ABSTRACT FROM AUTHOR]

Determining population growth across large scales is difficult because it is often impractical to collect data at large scales and over long timespans. Instead, the growth of a population is often only measured at a small, plot‐level scale and then extrapolated to derive a mean field estimate. However, this approach is prone to error since it simplifies spatial processes such as the neighbourhood effects of density and dispersal. We present a novel approach that estimates how spatial processes derived from the effects of density and dispersal affect population growth between plot scales and landscape scales. The method is based on a scale transition theory and calculates a transition term to measure the spatial scaling of population growth, which we extend to unstable, expanding populations in order to assess whether landscape‐scale population dynamics are different from those estimated at smaller spatial scales. We illustrate this approach using aerial imagery of eight locations in New Zealand experiencing non‐native pine invasions. Analyses examined the dynamics at a plot scale (1 ha) and compared this to estimates across entire landscapes (between 24 and 1600 ha), in several cases for more than one time period. We used a Bayesian spatial random effects model to examine population growth and to account for neighbourhood effects and dispersal between plots in a rapidly changing system. We found that the estimates of the scale transition term were typically 10–25% of the mean field estimates, which led to mean field estimates of population growth extrapolated from plots being considerably higher than landscape estimates. The approach we have developed will not only have applications for predicting the populations' growth of invasive species, but also for studies examining the scaling of landscape‐scale phenomena. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to assess the effect of changes in population size and migration on variation in functional immunity genes in the previously bottlenecked population of the grey wolf, Canis lupus. Location: Eastern/Central Europe: Poland, Czechia, Slovakia. Methods: We genotyped 7 immunity genes: three MHC‐DLA genes (dog leukocyte antigen) and four Toll‐like receptor (TLR) genes among 130 wolves originating from three populations: two lowland (Baltic and Central European), and highland Carpathian. We contrasted the population structure in immunity genes with a neutral structure based on 13 microsatellites, and we analysed signatures of selection in the immunity loci. Results: We found high overall genetic variance in immunity genes and no evidence for decreased diversity in the recently established populations. The population structure in immunity loci was weak, with pairwise FST lower than for neutral markers. Although the results of neutrality tests were not significant, we identified codons under selection, both positive and negative. Main Conclusions: We demonstrated that despite recent population expansion which is expected to result in decreased genetic diversity, the diversity of immunity genes in the newly established wolf population is similar to those in the source population. This suggests that migrations do not cause allele loss in grey wolf. Signatures of selection on codon level, but not in tests using allele frequencies, suggest the contrasting effects of demography and selection. [ABSTRACT FROM AUTHOR]

Aim: Up‐to‐date epidemiological studies on the global burden of severe periodontitis is scarce. This study aimed to present the latest estimates for prevalence of severe periodontitis from 1990 to 2019, by region, age, and level of socio‐demographic development. Materials and Methods: Estimates from the Global Burden of Disease study 2019 were used to investigate burden and trends of prevalence of severe periodontitis and its association with socio‐demographic development at global, regional, and national level. Decomposition analysis was performed to explore the contribution of demographic and epidemiological factors to the evolving burden of severe periodontitis. Results: In 2019, there were 1.1 billion (95% uncertainty interval: 0.8–1.4 billion) prevalent cases of severe periodontitis globally. From 1990 to 2019, age‐standardized prevalence rate of severe periodontitis increased by 8.44% (6.62%–10.59%) worldwide. Prevalence of severe periodontitis is higher among less developed countries/regions. Global population growth accounted for 67.9% of the increase in the number of prevalent cases of severe periodontitis from 1990 to 2019. Conclusions: The global burden of severe periodontitis has been substantial and increasing over the past three decades. Upstream policy changes are urgently needed to address the global public health challenge of severe periodontitis. [ABSTRACT FROM AUTHOR]

In organisms with dormant stages, life‐history responses to past pollution can be studied retrospectively. Here, we study such responses in a rotifer (Brachionus calyciflorus) from the once heavily copper‐polluted Lake Orta (Italy). We extracted resting eggs from sediments, established clonal lineages from hatchlings, and exposed newborns of these lineages to one of three copper concentrations that each mimicked a specific period in the lake's pollution history. For each rotifer, we daily collected life‐table data. We then estimated treatment‐specific vital rates and used a stage‐structured population model to project population growth rate λ. We also estimated elasticities of λ to vital rates and contributions of vital rates to observed Δλ between copper treatments. As expected, λ decreased with increasing copper concentration. This decrease resulted mostly from a decline in juvenile survival rate (SJ) and partly from a decline in the survival rate of asexually reproducing females (SA). Maturation rate, and with one exception fecundity, also declined but did not contribute consistently to Δλ. λ was most elastic to SJ and SA, indicating that survival rates were under stronger selection than maturation rate and fecundity. Together, our results indicate that variation in juvenile survival is a key component in the rotifers' copper response. The consistent decrease in SJ with increasing copper stress and the sensitivity of λ to that decrease also suggest that juvenile survival is a useful indicator of population performance under environmental pollution. [ABSTRACT FROM AUTHOR]