Regional Population Dynamics Research Articles

First Record of Bramble Sharks, Echinorhinus brucus (Echinorhiniformes, Echinorhinidae), in the United Arab Emirates

The first record of bramble sharks (Echinorhinus brucus) in the United Arab Emirates is presented. In situ observations of multiple bramble sharks were made at depths between 460 and 720 m from two piloted submersibles and a remotely operated vessel, representing the first known observations of this species in its native deep-water habitat in Arabia and the Indian Ocean. Notably, this research expands on the documented regional distribution of E. brucus for the Gulf of Oman/Arabian Sea and extends this species’ regional records to deeper mesophotic zones. These findings underscore the need for further research to understand the ecology and distribution of this cryptic shark species, particularly given its global endangered status and the limited knowledge of its regional population dynamics.

Foraging ecology of southern sea otters at the northern range extent informs regional population dynamics

Sea otters Enhydra lutris are vital keystone predators throughout the North Pacific that were nearly extirpated during the maritime fur trade. Recovery of southern sea otters E. l. nereis has proceeded slowly, with much of their historical range remaining unoccupied, resulting in reduced ecosystem functioning. Numerous studies have used foraging metrics to assess the population status of southern sea otters throughout their current range, but little is known about the northern range extent, where a stall in expansion has limited recovery. Thus, we collected census and foraging data of sea otters at Año Nuevo State Park, California, from 2019 to 2021 to determine sea otter abundance, diet composition, diet diversity, and average energy intake rate at the northern range edge. We then assessed regional population status by comparing values from Año Nuevo with previously collected data from other locations in California, including high-density, range center sites and low-density, range periphery sites. We found that sea otter density at Año Nuevo was greater than surrounding areas at the northern range periphery, and the average (±95% CI) energy intake (9.51 ± 0.91 kcal min-1) more closely resembled values observed at high-density sites. Further, dietary diversity (using the Shannon-Wiener index, H) was intermediate between previously studied high- and low-density populations (H = 1.81), with crabs making up the largest proportion of the diet (~56%). Overall, this study highlights possible effects of occupation time and range stagnation, identifies unique aspects of the prey resource base at Año Nuevo, and provides insight into the ongoing lack of northern range expansion.

Analysis of Genetic Structure and Genetic Diversity in Japanese Grey-Headed Lapwing Population Using mtDNA.

The grey-headed lapwing (Vanellus cinereus) is a wading species in East Asia. However, examples of regional population dynamics and genetic research are limited. To reconsider the natural history and current status of the grey-headed lapwing in Japan, we analyzed the genetic diversity of the Japanese grey-headed lapwing population. We collected 77 grey-headed lapwing samples from 12 locations across Japan during the breeding season and three individuals during the wintering season and extracted DNA; 496-bp sequences of the ND2, which form part of the mitochondrial DNA, were determined for genetic analysis of the population. Consequently, 10 haplotypes were detected in 80 individuals, and 67 individuals, 84% of the total, shared two haplotypes, namely Vc1 and Vc2. Furthermore, the results showed that the prevalence of Vc1 was higher mainly in northern Japan, while that of Vc2 was higher mainly in southern Japan. Genetic diversity analysis showed that the overall haplotype diversity in Japan was 0.617, which is not particularly low. The sequence of Vc1 was exactly the same as that of grey-headed lapwing in China. Our study revealed the genetic structure of the grey-headed lapwing, suggesting that as the grey-headed lapwing expanded its distribution area into southern Japan, many Vc2-positive individuals migrated southward, resulting in a higher detection rate of Vc2 in southern Japan.

Bird population changes in urban green spaces explained by regional population trends

Urban bird species represent a subset of the regional species pool, consisting of species that have been able to survive in, or colonise, urban areas. Urban birds are typically resident non-forest species with a broad diet and nesting high in trees or in cavities, and some studies have also claimed that they are large-brained. However, little is known about how urban bird communities change over time. Does the urban environment impose specific selective pressures favouring particular species or ecological groups, or do birds in urban areas simply have population changes reflecting population trends at larger scales? We assessed population changes of 45 breeding land bird species in Oslo, the capital of Norway, based on surveys conducted ca. 15 years apart. Population changes within Oslo most closely matched changes occurring at the regional level (national population trends from Norway and Sweden). Thus, species increasing in Oslo were those that also increased at the regional level. We found no evidence that relative brain size, diet or habitat preferences influenced population trends. However, controlling for regional population trends, there were additional residual effects of nest site and migration: species nesting on the ground or low in bushes had more positive changes than species nesting high in trees or in cavities, and resident species did better than long- or short-distance migrants. These results indicate that urban environments are not isolated islands only influenced by own selection pressures, but are connected with regional population dynamics, most likely through immigration.

Quantifying the impacts of management and herbicide resistance on regional plant population dynamics in the face of missing data

Abstract A key challenge in the management of populations is to quantify the impact of interventions in the face of environmental and phenotypic variability. However, accurate estimation of the effects of management and environment, in large‐scale ecological research is often limited by the expense of data collection, the inherent trade‐off between quality and quantity, and missing data. In this paper we develop a novel modelling framework, and demographically informed imputation scheme, to comprehensively account for the uncertainty generated by missing population, management, and herbicide resistance data. Using this framework and a large dataset (178 sites over 3 years) on the densities of a destructive arable weed (Alopecurus myosuroides) we investigate the effects of environment, management, and evolved herbicide resistance, on weed population dynamics. In this study we quantify the marginal effects of a suite of common management practices, including cropping, cultivation, and herbicide pressure, and evolved herbicide resistance, on weed population dynamics. Using this framework, we provide the first empirically backed demonstration that herbicide resistance is a key driver of population dynamics in arable weeds at regional scales. Whilst cultivation type had minimal impact on weed density, crop rotation, and earlier cultivation and drill dates consistently reduced infestation severity. Synthesis and applications: As we demonstrate that high herbicide resistance levels can produce extremely severe weed infestations, monitoring herbicide resistance is a priority for farmers across Western Europe. Furthermore, developing non‐chemical control methods is essential to control current weed populations, and prevent further resistance evolution. We recommend that planning interventions that centre on crop rotation and incorporate spring sewing and cultivation to provide the best reductions in weed densities. More generally, by directly accounting for missing data our framework permits the analysis of management practices with data that would otherwise be severely compromised.

Estimating blue mussel (Mytilus edulis) connectivity and settlement capacity in mid-latitude fjord regions.

The mussel industry faces challenges such as low and inconsistent levels of larvae settlement and poor-quality spat, leading to variable production. However, mussel farming remains a vital sustainable and environmentally responsible method for producing protein, fostering ecological responsibility in the aquaculture sector. We investigate the population connectivity and larval dispersion of blue mussels (Mytilus edulis) in Scottish waters, as a case study, using a multidisciplinary approach that combined genetic data and particle modelling. This research allows us to develop a thorough understanding of blue mussel population dynamics in mid-latitude fjord regions, to infer gene-flow patterns, and to estimate population divergence. Our findings reveal a primary south-to-north particle transport direction and the presence of five genetic clusters. We discover a significant and continuous genetic material exchange among populations within the study area, with our biophysical model's outcomes aligning with our genetic observations. Additionally, our model reveals a robust connection between the southwest coast and the rest of the west coast. This study will guide the preservation of mussel farming regions, ensuring sustainable populations that contribute to marine ecosystem health and resilience.

The importance of naturalized quarries as amphibian breeding sites: a case study in central Spain

Naturalized quarries can host rich amphibian communities, potentially playing an important role in local and regional population dynamics. Despite their importance for conservation, few studies have evaluated their potential to host large, viable populations and to connect breeding nuclei in neighboring areas, promoting long-term demographic resilience at the regional scale. We used photo-identification as a capture-mark-recapture method to estimate the population sizes and dispersal patterns of two amphibians of regional conservation concern (Pleurodeles waltl and Pelodytes punctatus), which breed in temporary ponds in an abandoned, naturalized quarry in SE Madrid (central Spain). We also surveyed all water bodies potentially harboring amphibian populations in an 80 km2 area centered in our study site to detect additional breeding nuclei of the two species. Both species are abundant in the core study site, with estimated population sizes of around 300 individuals in P. waltl and about 800 in P. punctatus. We recorded 23 accumulated displacements, ranging from 80 to 840 m, performed by 20 individuals of P. waltl captured on multiple occasions, but were unable to detect spatial displacements of P. punctatus during the study. Regional surveys confirmed the presence of P. waltl and/or P. punctatus in 7 additional locations, mostly quarries, at distances of 0.6-4.4 km from the study site. Our results show that temporary ponds in naturalized quarries can represent key assets for the long-term resilience of amphibian populations in areas where human action has resulted in extensive habitat fragmentation and loss.

Increasing marsh bird abundance in coastal wetlands of the Great Lakes, 2011–2021, likely caused by increasing water levels

Abstract Wetlands of the Laurentian Great Lakes of North America (i.e., lakes Superior, Michigan, Huron, Erie, and Ontario) provide critical habitat for marsh birds. We used 11 years (2011–2021) of data collected by the Great Lakes Coastal Wetland Monitoring Program at 1,962 point-count locations in 792 wetlands to quantify the first-ever annual abundance indices and trends of 18 marsh-breeding bird species in coastal wetlands throughout the entire Great Lakes. Nine species (50%) increased by 8–37% per year across all of the Great Lakes combined, whereas none decreased. Twelve species (67%) increased by 5–50% per year in at least 1 of the 5 Great Lakes, whereas only 3 species (17%) decreased by 2–10% per year in at least 1 of the lakes. There were more positive trends among lakes and species (n = 34, 48%) than negative trends (n = 5, 7%). These large increases are welcomed because most of the species are of conservation concern in the Great Lakes. Trends were likely caused by long-term, cyclical fluctuations in Great Lakes water levels. Lake levels increased over most of the study, which inundated vegetation and increased open water-vegetation interspersion and open water extent, all of which are known to positively influence abundance of most of the increasing species and negatively influence abundance of all of the decreasing species. Coastal wetlands may be more important for marsh birds than once thought if they provide high-lake-level-induced population pulses for species of conservation concern. Coastal wetland protection and restoration are of utmost importance to safeguard this process. Future climate projections show increases in lake levels over the coming decades, which will cause “coastal squeeze” of many wetlands if they are unable to migrate landward fast enough to keep pace. If this happens, less habitat will be available to support periodic pulses in marsh bird abundance, which appear to be important for regional population dynamics. Actions that allow landward migration of coastal wetlands during increasing lake levels by removing or preventing barriers to movement, such as shoreline hardening, will be useful for maintaining marsh bird breeding habitat in the Great Lakes.

Internal migration and settlement patterns in Australia's regional urban centres

AbstractThe distribution of population between metropolitan regions and their rural counterparts is a topic of interest, due to the growth pressures in large cities and areas of decline in some, typically remote regions. In Australia, fostering population growth in regional urban centres (RUCs) has been a long‐term goal of government policy. Understanding the different profiles, structures, and population dynamics of Australia's RUCs is critical in informing Australian regional development, as well as factors in regional population dynamics in general. This research is focused on patterns of population change through internal migration across Australian RUCs. In addition to a detailed spatial analysis of patterns of population migration flows, this research offers a comprehensive analysis of a range of regional social, economic and infrastructure development factors and their effects on regional migration and population changes. The outputs of the method are new evidence to inform the future regional plan to increase economic and population growth in RUCs. This research contributes to population research and regional planning and provides a baseline for the prepandemic status of regional population dynamics in Australia.

Effects of local density dependence and temperature on the spatial synchrony of marine fish populations.

Disentangling empirically the many processes affecting spatial population synchrony is a challenge in population ecology. Two processes that could have major effects on the spatial synchrony of wild population dynamics are density dependence and variation in environmental conditions like temperature. Understanding these effects is crucial for predicting the effects of climate change on local and regional population dynamics. We quantified the direct contribution of local temperature and density dependence to spatial synchrony in the population dynamics of nine fish species inhabiting the Barents Sea. First, we estimated the degree to which the annual spatial autocorrelations in density are influenced by temperature. Second, we estimated and mapped the local effects of temperature and strength of density dependence on annual changes in density. Finally, we measured the relative effects of temperature and density dependence on the spatial synchrony in changes in density. Temperature influenced the annual spatial autocorrelation in density more in species with greater affinities to the benthos and to warmer waters. Temperature correlated positively with changes in density in the eastern Barents Sea for most species. Temperature had a weak synchronizing effect on density dynamics, while increasing strength of density dependence consistently desynchronised the dynamics. Quantifying the relative effects of different processes affecting population synchrony is important to better predict how population dynamics might change when environmental conditions change. Here, high degrees of spatial synchrony in the population dynamics remained unexplained by local temperature and density dependence, confirming the presence of additional synchronizing drivers, such as trophic interactions or harvesting.

SINE QUA NON: INFERRING KODJADERMEN-GUMELNIȚA-KARANOVO VI POPULATION DYNAMICS FROM AGGREGATED PROBABILITY DISTRIBUTIONS OF RADIOCARBON DATES

ABSTRACTPast human population dynamics play a key role in integrated models of understanding socio-ecological change over time. However, little analysis on this issue has been carried out for the prehistoric societies in the Lower Danube and Eastern Balkans area. Here, we use summed probability distributions of radiocarbon dates to investigate potential regional and local variation population dynamics. Our study adopts a formal model-testing approach to the fifth millennium BC archaeological radiocarbon record, performing a region-wide, comparative analysis of the demographic trajectories of the area along lower Danube River. We follow the current framework of theoretical models of population growth and perform global and regional significance and spatial permutation tests on the data. Specifically, we investigate whether populations on both sides of the Danube follow a logistic pattern of steady growth, followed by a major decline over time. Finally, our analysis of local-scale growth investigates whether considerable heterogeneity or homogeneity within the region may be observed over the time span considered here. The results show both similarities and differences in the population trends across the area. Our findings are showcased in relation to the cultural characteristics of the region’s 5th millennium BC societies, and future research directions are also suggested.

The Relationship between Refugee Pressure and Local Control under the Patriarch of the Greek Orthodox Patriarchate of Alexandria

The beginning of the 7th century was of major conflict and changes to the people residing within the borders of the East Roman Empire, with the revolt of Phocas, the seizing power of Heraclius, and later, the invasion of the Persians all happening together within a narrow time duration. All of these conflicts had major effects on regional population and power dynamics structure. This paper discusses the assumption that the Orthodox Patriarchate of Alexandria, under the leadership of John the almsgiver, dealt with refugees fleeing Levant. It transformed refugees into hermits and built local influence in the process. The paper uses autobiographical primary sources and references to the geological conditions then. In the fifth century, the Council of Chalcedon re-asserted the teachings of the Ecumenical Council of Ephesus against the heresies of Eutyches and Nestorius, leading to a grand division within Egypt. The consequences—the commemoration of two non-Chalcedonian churches along with the absence of imperial influence due to the Byzantine-Persian War—prompted Patriarch John of the Orthodox Church of Alexandria to take measures to create new hermit populations from the refugees in Jerusalem to once again infiltrate church control.

Moving Direction Entropy as Index for Inter-community Activity

Since we presented the Stay with Your Community principle for suppressing the infection spread at the social level, policies on SWYC have been considered in the context of the tradeoff between the risk of infection spreading and the benefit of inter-community interaction on productive and innovative social activities. In this paper, Moving Direction Entropy is defined as a value representing the diversity of humans’ moving direction in each region. This value had been found to be positively correlated with the number of COVID-19 positive cases, and here it is shown to be in positive correlation with the regional population of inbound flow and its increase during the analyzed period from 2019 through 2022. The results have double implications (1) the dynamics of regional populations, regarded as the enhancement of inter-community interaction, diversify the movements and (2) such dynamics are likely to foster infection spreading.

Бедность и экономический рост в российских агломерациях: тенденции и зависимости

Strategic documents define a list of Russian agglomerations that are expected to significantly contribute to the national economy. However, the question whether there is potential to achieve the set goals remains unresolved. Population dynamics as a key aspect of economic sustainability of agglomerations and regions can lead to a transformation of economic potential. The study aims to clarify and quantify the relationship between the parameters of poverty and economic growth considering the population dynamics of agglomerations and regions. Official statistics, as well as the SPARK-Interfax database of companies’ performance indicators were analysed. The article uses statistical and econometric methods. The 2008-2022 data on population dynamics in agglomerations and regions of their location were used to establish a typology of Russian agglomerations. At the next stage, a regression model of the relationship between the proportion of people living in poverty and gross metropolitan product per capita was built based on the 2008-2020 data. As a result, the Kuznets hypothesis was rejected. The following relationship is observed in all agglomerations: after the turning point, economic growth is accompanied by an increase in poverty. The transition poverty level is 6.6 % for Saint Petersburg, 12.9 % for Novosibirsk and 13.8 % for Vladivostok. Analysis of the hypothesis of List and Gallet for agglomerations characterised by positive population dynamics (Saint Petersburg and Novosibirsk) proved that poverty declines accompanied by further economic growth after the poverty rate of 9.1 % and 14.8 %, respectively. The findings can be used to formulate management responses to the challenges associated with negative socio-economic trends. Future studies can expand the list of examined agglomerations and consider their industry profiles for a more detailed assessment of the impact of transformational changes.

Analisis Potensi Ekonomi Dan Kependudukan Dalam Pertumbuhan Ekonomi Di Kabupaten Mamuju Provinsi Sulawesi Barat

To increase the rate of economic growth of a region, it is necessary to assess the economic sector owned which is progressing every year. The purpose of this research on population economics in Mamuju is to identify potentials and see growth trends in each economic sector in Mamuju. The method used is analysis of Location Quotients (LQ) and Shift Share. The economic sector is linked to population dynamics to see the relationship between regional economy and population dynamics in Mamuju as a material for determining development planning strategies in the economic sector. Of the 17 existing sectors, there are 13 sectors which are the base sector and are progressing in contributing to the value of PDRB. From these results and supported by the dynamics of the increasing population, Mamuju Regency needs to increase the contribution of the sector to meet the needs of residents inside and outside Mamuju Regency.

Parsimonious stochastic forecasting of international and internal migration on the NUTS-3 level – an outlook of regional depopulation trends in Germany

Substantiated knowledge of future demographic changes that is derived from sound statistical and mathematical methods is a crucial determinant of regional planning. Of the components of demographic developments, migration shapes regional demographics the most over the short term. However, despite its importance, existing approaches model future regional migration based on deterministic assumptions that do not sufficiently account for its highly probabilistic nature. In response to this shortcoming in the literature, our paper uses age- and gender-specific migration data for German NUTS-3 regions over the 1995–2019 period and compares the performance of a variety of forecasting models in backtests. Using the bestperforming model specification and drawing on Monte Carlo simulations, we present a stochastic forecast of regional migration dynamics across German regions until 2040 and analyze their role in regional depopulation. The results provide evidence that well-known age-specific migration patterns across the urban-rural continuum of regions, such as the education-induced migration of young adults, are very likely to persist, and to continue to shape future regional (de)population dynamics.

Multiscale Brain Network Models and Their Applications in Neuropsychiatric Diseases

With the rapid development of advanced neuroimaging techniques, understanding the brain in terms of structural and functional connectomes has become one of the frontier topics in neuroscience. Different from traditional descriptive brain network models, which focused on single neuroimaging modal and temporal scales, multiscale brain network models consisting of mesoscopic neuronal activity and macroscopic functional dynamics can provide a mechanistic understanding for brain disorders. Here, we review the foundation of multiscale brain network models and their applications in neuropsychiatric diseases. We first describe some basic elements of a multiscale brain network model, including network connections, dynamics of regional neuronal populations, and model fittings to different metrics of fMRI. Secondly, we draw comparisons between multiscale brain network models and other large-scale brain models. Additionally, then we survey the related applications of multiscale brain network models in understanding underlying mechanisms of some brain disorders, such as Parkinson’s disease, Alzheimer’s disease, and Schizophrenia. Finally, we discuss the limitations of current multiscale brain network models and future potential directions for model development. We argue that multiscale brain network models are more comprehensive than traditional single modal brain networks and would be a powerful tool to explore neuronal mechanisms underlying different brain disorders measured by neuroimaging.

Modeling the impact of genetically modified male mosquitoes in the spatial population dynamics of Aedes aegypti

The mosquito Aedes aegypti is the primary vector of diseases such as dengue, Zika, chikungunya, and yellow fever. Improving control techniques requires a better understanding of the mosquito’s life cycle, including spatial population dynamics in endemic regions. One of the most promising techniques consists of introducing genetically modified male mosquitoes. Several models proposed to describe this technique present mathematical issues or rely on numerous parameters, making their application challenging to real-world situations. We propose a model describing the spatial population dynamics of the Aedes aegypti in the presence of genetically modified males. This model presents some mathematical improvements compared to the literature allowing deeper mathematical analysis. Moreover, this model relies on few parameters, which we show how to obtain or estimate from the literature. Through numerical simulations, we investigate the impacts of environmental heterogeneity, the periodicity of genetically modified male releases, and released genetically modified males quantity on the population dynamics of Aedes aegypti. The main results point to that the successful application of this vector control technique relies on releasing more than a critical amount of modified males with a frequency exceeding a specific critical value.

Analysis of Genetic Structure and Genetic Diversity in Japanese Black Kite Population Using mtDNA.

The black kite (Milvus migrans) is widespread in the "Old World" and is a common raptor species in Japan. However, examples of regional population dynamics and genetic research are limited. To reconsider the natural history and current status of the black kite in Japan, we analyzed the genetic diversity of the Japanese black kite population. We collected 59 black kite samples from 22 locations across Japan and extracted DNA; 1585 bp sequences of the cytochrome b and control region, which form part of the mitochondrial DNA, were determined for genetic analysis of the population. Consequently, six haplotypes were detected in 59 individuals, 50 of which had the same major haplotype, namely, Mm1. Moreover, the genetic analysis indicated that the Japanese black kite population would fit the population expansion model. Phylogenetic analysis using sequences obtained in this study or from a DNA database indicated that the Japanese black kite population can be divided into two groups: (1) Mm1 and its close haplotypes and (2) Mm5. The sequence of Mm1 was exactly the same as that of black kite in Pakistan, India, and Korea, suggesting that this haplotype is generally widespread in East Eurasia, and that the ancestral haplotype of the Japanese population likely migrated from continental East Asia and expanded its distribution throughout Japan. In summary, we found that the black kite population in East Eurasia, including Japan, is composed of at least two lineages.

Measuring Multiple Demographic Rates in Two Populations of Northern Bobwhite

Demographic rates of northern bobwhite (Colinus virginianus; hereafter, bobwhite) may vary spatially and temporally, and understanding the significance of these individual rates to population performance is critically important to bobwhite management. We present descriptive evidence from 2 populations that were simultaneously monitored from 2015–2020 that suggests different demographic rates can be more important to population performance than other demographic rates within the same region. Our objective was to understand the relative importance of various demographic rates to population performance in separate and seemingly stable populations. We monitored bobwhite seasonal survival and reproductive demographics on 2,475 bobwhites via radio-telemetry and estimated fall density using fall covey counts. Both sites maintained high densities (i.e., ≥3.45 birds/hectare) and remained relatively stable throughout the study period. On one site in the Red Hills region near Monticello, Florida, USA, bobwhite experienced comparatively low seasonal survival, but higher reproduction, including more frequent multiple-brood production. One hundred and twenty-nine kilometers away on a study site near Albany, Georgia, USA, bobwhite demonstrated consistently higher survival and lower reproductive output, including less multiple-brooding compared to the Red Hills population. This suggests, at a minimum, that compensatory or density-dependent reproduction may be occurring in these populations and regional population dynamics can vary locally even among stable populations.