Epidemiology of Animal Poisonings in the Canary Islands (Spain) during the Period 2014–2021

Fluctuating population density in stochastic environments can contribute to maintain life-history variation within populations via density-dependent selection. We used individual-based data from a population of Soay sheep to examine variation in life-history strategies at high and low population density. We incorporated life-history trade-offs among survival, reproduction and body mass growth into structured population models and found support for the prediction that different life-history strategies are optimal at low and high population densities. Shorter generation times and lower asymptotic body mass were selected for in high-density environments even though heavier individuals had higher probabilities to survive and reproduce. In contrast, greater asymptotic body mass and longer generation times were optimal at low population density. If populations fluctuate between high density when resources are scarce, and low densities when they are abundant, the variation in density will generate fluctuating selection for different life-history strategies, that could act to maintain life-history variation.

Dispersal is the process that allows organisms to reach new suitable territories and expand their area of occupancy. In plants, long-distance dispersal (LDD) of diaspores is related to the presence of morphological structures (dispersal syndromes) that favor mobility by wind (anemochorous), sea currents (thalasochorous) and animals (epizoochorous and endozoochorous). The relationship between these LDD structures and the distribution of plant species is related to characteristics of different archipelagoes. Previous studies in several archipelagoes found that the Canary Islands showed the strongest positive relationship between dispersal syndromes and species distributions. It has been long hypothesized that species without specialized structures for dispersal have more difficulties in expanding their areas of occupancy and consequently these species are more threatened because of limited distribution. Nevertheless, the effect of the dispersal ability of plant species on the degree of threat has never been tested in oceanic archipelagoes. In this study, we selected the 262 lowland endemic plant species of the Canary Islands and evaluated the relationship between the presence/absence of the four LDD syndromes and their threat status. A considerable number of threatened (154 spp.) and non-threatened (108 spp.) species were observed, of which 93 had LDD syndromes and 169 did not. Our analyses failed to find statistically significant differences between the number of threatened species with and without LDD syndromes and their IUCN threatened status. In sum, this study shows a poor contribution of dispersal abilities in the degree of threat of endemic plant species in the Canary Islands.

Integrating multiple lines of evidence to assess freshwater ecosystem health in a tropical river basin

Relevance. Road traffic injuries are one of the leading non-natural causes of death in the world. The principles of organizing the provision of medical care to victims of road traffic accidents (RTA) should be adapted to the resource capabilities of regional health care systems, as well as the distribution of the resident population across the territory.Intention: To develop and substantiate the principles of a system for organizing the provision of medical care to RTA victims on federal highways in Russian regions with a low average population density.Methodology. The results of our own, domestic and foreign scientific research were reviewed, along with regulatory legal documents on the organization of medical care for RTA victims in various conditions. Articles published in 1990–2021 were selected for analysis. Information sources were searched for using specialized scientific search engines (eLibrary, PubMed, Scopus) with the keywords: “traffic accident”, “traffic injury”, “polytrauma”, “federal highway”, “injured”, “hospital period “. System analysis was used to determine the shortcomings of the existing system of providing medical care to victims of road accidents that occurred on federal highways in the territories of Russian subjects with a low population density. Organizational experiments were used to substantiate and develop measures, the implementation of which will improve the efficiency of providing first aid and medical care to victims of road accidents on federal highways in Russian regions with a low population density.Results and Discussion. A system for organizing the provision of medical care to victims of road accidents on federal highways in the regions of the Russian Federation with a low density of the population in the pre-hospital and hospital periods has been developed and justified; it consists of 4 principles and their organizational measures.Conclusion. The implementation of the model and the principles of the developed system proposed by the author will reduce negative health consequences associated with road traffic injuries on federal highways in Russian regions with low population density.

Progenies from three soybean (Glyelne max (L.) Merr.) crosses were advanced four generations by single seed descent in the greenhouse. Plants were grown at two populations, three plants/15 cm pot and nine plants/15 cm pot. Plant losses averaged 19% of the original population at the low density and 55% of the original population at the high density at the end of the four generations.Gene frequencies for flower and pubescence color did not deviate from theoretical frequencies in the low density populations. At the high density population, significant deviations from expected values occurred for flower color in two crosses andf or pubescencceo lor in all three crosses. In two crosses the incidence of plants heterozygous for the gene controlling reaction to race 1 of Phytophthora megasperma Drechs. var. sojae Hildebrand was higher than expected.A two replicate field test was used to evaluate progenies from the low and high density populations for maturity, lodging, plant height, and seed size. Progenies advanced from the high density population averaged 0.5 to 3.6 days later in maturity, 0.I to 0.2 higher in lodging score, and 0 to 4.3 cm taller than progenies advanced from the low density population.

The objective of this study was to estimate and compare the occurrence of AMR in wild red foxes in relation to human population densities. Samples from wild red foxes (n = 528) included in the Norwegian monitoring programme on antimicrobial resistance in bacteria from food, feed and animals were included. All samples were divided into three different groups based on population density in the municipality where the foxes were hunted. Of the 528 samples included, 108 (20.5%), 328 (62.1%) and 92 (17.4%) originated from areas with low, medium and high population density, respectively. A single faecal swab was collected from each fox. All samples were plated out on a selective medium for Enterobacteriaceae for culturing followed by inclusion and susceptibility testing of one randomly selected Escherichia coli to assess the overall occurrence of AMR in the Gram-negative bacterial population. Furthermore, the samples were subjected to selective screening for detection of E. coli displaying resistance towards extended-spectrum cephalosporins and fluoroquinolones. In addition, a subset of samples (n = 387) were subjected to selective culturing to detect E. coli resistant to carbapenems and colistin, and enterococci resistant to vancomycin. Of these, 98 (25.3%), 200 (51.7%) and 89 (23.0%) originated from areas with low, medium and high population density, respectively. Overall, the occurrence of AMR in indicator E. coli from wild red foxes originating from areas with different human population densities in Norway was low to moderate (8.8%). The total occurrence of AMR was significantly higher; χ2 (1,N = 336) = 6.53, p = 0.01 in areas with high population density compared to areas with medium population density. Similarly, the occurrence of fluoroquinolone resistant E. coli isolated using selective detection methods was low in areas with low population density and more common in areas with medium or high population density. In conclusion, we found indications that occurrence of AMR in wild red foxes in Norway is associated with human population density. Foxes living in urban areas are more likely to be exposed to AMR bacteria and resistance drivers from food waste, garbage, sewage, waste water and consumption of contaminated prey compared to foxes living in remote areas. The homerange of red fox has been shown to be limited thereby the red fox constitutes a good sentinel for monitoring antimicrobial resistance in the environment. Continuous monitoring on the occurrence of AMR in different wild species, ecological niches and geographical areas can facilitate an increased understanding of the environmental burden of AMR in the environment. Such information is needed to further assess the impact for humans, and enables implementation of possible control measures for AMR in humans, animals and the environment in a true “One Health” approach.

In Russia, socio-demographic, health care management, climatic and environmental TB risk factors such as population density, intensity of social contacts, availability of medical care, seasonal climate changes, environmental issues affecting quality of public health have been holding the leading place while a life standard elevates, and epidemic situation becomes improved. However, the magnitude of specific population density-related TB risk factors in the Russian regions has not been examined yet. The study aim was to assess structured TB risk factors in the Russian regions with high and low population densities decreasing public health quality. Materials and methods. There was conducted a study using sociological, cluster-quota approaches, with respondent-based sample and a face-to-face distribution questionnaire provided by 2500 subjects, of which 1497 were from the North Ossetia-Alania Republic with a high population density, 1003 — from the Republic of Karelia with a low population density. A significance of differences was assessed by using exact criterion Fisher using a contingency table. Results. In the Republic of Karelia, compared with North Ossetia-Alania Republic, despite a higher gross regional product (527.8 thousand rubles vs 293.4 thousand rubles, p 0.000), social and behavioral TB risk factors were significantly elevated: fewer respondents with high education (18.4% vs 33.6%, p 0.000), higher divorced (18.7% vs 26.9%, p 0.022), higher number of those living in apartment buildings (65.0% vs 39.5%, p 0.000), more hired and seasonal workers, unemployed, pensioners due to age and disability (55.0% vs 32.3%, p 0.000), more alcohol abusers (67.4% vs 34.3%, p 0.000), “heavy” smokers (20.8% vs 7.2%, p 0.000), more subjects with chronic diseases (43.7% vs 32.1%, p 0.02); more issues related to accessibility to medical care: municipal policlinics are less available (42.7% vs 85.6%, p 0.000), the distant location of medical facilities (21.4% vs 2.7%, p 0.000), lack of transport links (15.7% vs 8.5%, p 0.000), poor roads (5.9% vs 16.9%, p 0.000) and few medical specialists (60.9% vs 16,8%, p 0.000) are more often noted. In the North Ossetia-Alania Republic vs the Republic of Karelia, respondents had more frequent social contact with TB patients (66.9% vs 34.8%, p 0.000). Conclusion. The epidemiological TB factors in the Russian regions with high population density hold a lead place; in regions with low population density, social, behavioral and accessibility to medical care factors remain relevant, which should be taken into account while developing measures for efficient management of epidemic process.

Between 1999 and 2005, 233 stranded cetaceans (comprising 19 species) were reported in the waters of the Canary Islands. Of these, 138/233 (59.2%) were subjected to a complete or partial standardized necropsy, including 4 Balaenopteridae, 9 Physeteridae, 8 Kogiidae, 27 Ziphiidae and 90 Delphinidae. Of these, 46/138 (33.3%) cetaceans were diagnosed with anthropogenic pathological categories (i.e. the cause of death was anthropogenic). These included fishing interaction (bycatch) (19 individuals), 'atypical' mass stranding events linked to naval exercises (13), ship collisions (8) and other anthropogenic-related pathology (6). 'Natural' (i.e. non-anthropogenic) causes of death accounted for another 82/138 (59.4%) cases, including infectious and non-infectious diseases (63), neonatal pathology (8), intra- and interspecific interactions (6) and mass strandings (5). The cause(s) of death could not be determined in 10/138 (7.3%) necropsied animals. The most common causes of death were ship collisions in 6/9 (66.6%) Physeteridae, 'atypical' mass stranding linked to naval exercises in 13/27 (48.1%) Ziphiidae, and 'natural' infectious and non-infectious diseases in 55/90 (61.1%) Delphinidae. Interaction with fishing activities was established as cause of death in 15/90 (16.7%) Delphinidae. These data show that a range of anthropogenic and natural single and mass mortality events occur in multiple cetacean species stranded in the Canary Islands.

Limited availability of mating partners has been proposed as an explanation for the occurrence of simultaneous hermaphroditism in animals with pair mating. When low population density or low mobility of a species limits the number of potential mates, simultaneous hermaphrodites may have a selective advantage because, first, they are able to adjust the allocation of resources between male and female functions in order to maximize fitness; second, in a hermaphroditic population the likelihood of meeting a partner is higher because all individuals are potential mates; and, third, in the absence of mating partners, many simultaneously hermaphroditic animals have the option of reproducing through self-fertilization. Recognizing that mate availability is central to the existing theory of hermaphroditism in animals, it is important to examine the effects of mate search on predictions of the stability of hermaphroditism. Many hermaphroditic animals can increase the number of potential mates they contact by active searching. However, since mate search has costs in terms of time and energy, the increased number of potential mates will be traded off against the amount of resources that can be allocated to the production of gametes. We explore the consequences of this trade-off to the evolution of mating strategies and to the selective advantage of self-fertilization. We show that in low and moderate population densities, poor mate-search efficiency and high costs of searching stabilize hermaphroditism and bias sex allocation toward female function. In addition, in very low population densities, there is strong selective advantage for self-fertilization, but this advantage decreases considerably in species with high mate-search efficiency. Most important, however, we present a novel evolutionary prediction: when mate search is efficient, disruptive frequency-dependent selection on time allocation to mate search leads to the evolution of searching and nonsearching phenotypes and, ultimately, to the evolution of males and females.

There is much debate about the conservation status of the koala (Phascolarctos cinereus) on a statewide and national scale. Abundance estimates vary greatly, particularly in Victoria and Queensland. My research helps to clarify this situation by deriving an abundance estimate of 63 000 ± 18 000 koalas in the mulgalands of southwest Queensland, a semi-arid rangeland which covers an area of around 20 million hectares. This thesis also provides an insight into the factors that determine koala distribution and density in semi-arid environments. The broadscale survey design and sampling strategy developed to survey a large heterogeneous region is the initial focus of the thesis. The development of such a sampling strategy is framed by two primary considerations. Firstly, the low density koala populations of the region, arid secondly, the broadscale nature of the research. Conventional survey methods, such as direct counts, are often unsuitable for surveying low-density animal populations, particularly on a broadscale. This thesis details the development of the first faecal pellet sampling methodology to estimate the abundance of an arboreal mammal. This methodology was applied within the framework of a multi-scaled stratified survey design developed to capture factors that determine the distribution and density of koalas at different scales. The pellet sampling methodology is based on the quick and accurate identification of trees which have koala faecal pellets beneath them. Pellet abundance was then estimated by conducting counts in quadrats distributed proportionally to canopy area. These data, along with mean daily pellet production and pellet age data were converted to estimates of koala abundance using the faecal standing crop method. Distribution and abundance data were collected from 149 sites located throughout the study area. These data indicate that the eastern portion of the study area has the most uniform distribution and highest densities of koalas. Koalas were also recorded in the central and western regions of the study area. Koala distribution within the study area appears to be largely determined by water availability, while the physiography and edaphic characteristics of specific landform types appear to determine the level of utilisation within these boundaries. The highest density populations occur in riverine communities. Low density populations are spread throughout dissected residual communities in the central and eastern portion of the study area, and are also scattered throughout floodplain and plains communities, particularly in the east. To determine the variance around the koala abundance estimate a bootstrap/Monte Carlo exercise was conducted. Riverine and dissected residual koala populations comprise >90% of this estimate. The relative importance of residual communities as habitat is critical to the future management of the koalas, which were considered to be largely restricted to riverine communities. The highly variable environment of the mulgalands and land management practices associated with grazing have created an inherently dynamic environment with many seral plant communities of varying stability. The region has a long history of vegetation clearance and fragmentation, a change in species dominance from perennial grasses to trees and shrubs and a reduced fire frequency. I also formulated region specific management recommendations that account for the detrimental impacts of land management practices on koala conservation. For too long the koala conservation debate has been guided by anecdotal evidence and 'best guesses' of their abundance, particularly for inland populations. Regardless of whether koala abundance is considered in light of conservative or more generous estimates, this research shows that the mulgalands contain a significant proportion of Australia's koala population. These populations appear to be relatively stable and are under less immediate threat than many coastal populations, particularly in New South Wales and Queensland. Future koala conservation initiatives should include the vast regions of semi-arid Queensland that comprise a substantial proportion of its current range.

Background. The organization of public transport routes based on individual passenger requests (on-demand routes) using small-class buses in areas with low population density has become a pressing issue due to the necessity of improving the efficiency of transport systems under limited financial and material resources. Traditional regular route schemes often prove unprofitable and insufficiently convenient for residents of such territories, leading to decreased transport accessibility and deterioration of population living standards. Modern technologies and mathematical modeling enable the development of flexible and cost-effective solutions capable of adapting to the characteristics of low-density regions and minimizing costs associated with organizing transport services. The need for optimizing transport flows acquires particular significance in light of global sustainable development and environmental trends. Developing models that reduce operational expenses and decrease the carbon footprint of transport operations corresponds to modern requirements for rational natural resource utilization and energy efficiency. Creating effective mechanisms for managing on-demand routes holds high social significance, contributing to ensuring equal opportunities for all segments of the population regardless of their geographical location and financial status. Purpose. To develop a mathematical model for organizing on-demand routes for passenger transportation using small-class buses in populated areas with low population density, ensuring maximum efficiency and economic viability of transport services. Materials and methods. This study employed a comprehensive approach to developing a mathematical model for organizing on-demand routes. The research was based on analyzing real conditions of bus service operation in regions with low population density. The model considered the following parameters: number of populated areas and their geographic location, passenger flow volume, technical specifications of small-class buses, time constraints, and financial performance indicators of transport enterprises. Route optimization was performed using dynamic programming algorithms that accounted for variable demand structure and resource limitations. Practical testing of the model was conducted using data from a specific region with low population density, enabling the collection of reliable results and drawing conclusions about the effectiveness of the proposed approach to organizing transport services. Results. A comprehensive analysis of existing approaches to organizing on-demand routes was conducted, and key factors determining their effectiveness were identified. A mathematical model was developed that accounts for the specifics of populated areas with low population density, including uneven distribution of demand, large distances between populated areas, and limited financial resources. Various route optimization algorithms were investigated, and the most suitable method was selected for solving the stated problem. Numerical simulation of the proposed model was performed using a specific regional example, and its effectiveness was evaluated compared to existing transportation schemes. Recommendations were developed for implementing the proposed model in the practical activities of transport organizations operating in conditions of low population density.

Understanding the drivers of forest aboveground biomass (AGB) is essential to further understanding the forest carbon cycle. In the upper Yangtze River region, where ecosystems are incredibly fragile, the driving factors that make AGB changes differ from other regions. This study aims to investigate AGB’s spatial and temporal variation of Pinus densata in Shangri-La and decompose the direct and indirect effects of spatial attribute, climate, stand structure, and agricultural activity on AGB in Shangri-La to evaluate the degree of influence of each factor on AGB change. The continuous sample plots from National Forest Inventory (NFI) and Landsat time series were used to estimate the AGB in 1987, 1992, 1997, 2002, 2007, 2012, and 2017. The structural equation model (SEM) was used to analyze the different effects of the four factors on AGB based on five scales: entire, 1987–2002, 2007–2017, low population density, and high population density. The results are as follows: (1) The AGB of Pinus densata in Shangri-La decreased from 1987 to 2017, with the total amount falling from 9.52 million tons to 7.41 million tons, and the average AGB falling from 55.49 t/ha to 40.10 t/ha. (2) At different scales, stand structure and climate were the drivers that directly affect the AGB change. In contrast, the agricultural activity had a negative direct effect on the AGB change, and spatial attribute had a relatively small indirect effect on the AGB change. (3) Analyzing the SEM results at different scales, the change of the contribution of the agricultural activity indicates that human activity is the main negative driver of AGB change in Shangri-La, especially at the high population density region. In contrast, the change of the contribution of the stand structure and climate indicates that the loss of old trees has an important influence on the AGB change. Forest resources here and other ecologically fragile areas should be gradually restored by adhering to policies, such as strengthening forest protection, improving forest stand quality, and limiting agricultural production activities.

This study aimed to identify reported causes of neonatal death across the European Economic Area (EEA) member states and Switzerland as of 1 January 2010 (hereafter referred to as the European Region) and, where possible, examine the cause-specific distribution of neonatal deaths over time. We conducted a two-pronged analysis: (1) database analysis using WHO public datasets (2000–2021) for 28 countries in the European Region and (2) a systematic review and meta-analysis of pertinent records from PubMed, Embase, Web of Science, Scopus, Cochrane, and Google Scholar, which were comprehensively reviewed against inclusion criteria up to 10 August 2024, following PRISMA guidelines. The average neonatal mortality rate (NMRs) between 2000 and 2021 in WHO data was 2.63 per 1000 live births, with a significant decline (−0.074 per year) across the region. Prematurity (41.2%) and congenital anomalies (28.9%) were the most common registered causes of neonatal death; however, WHO data lacked etiological detail to reliably analyze cause-specific trends. The systematic review identified 41 eligible studies, of which 15 were included in meta-analyses. Pooled estimates showed that congenital anomalies and prematurity accounted for 30% (95% CI 17–46) and 31% (95% CI 18–49) of deaths, respectively. Among extremely preterm neonates, infections, respiratory, and cardiovascular disorders were the most common reported causes of death. Conclusion: NMRs across the European Region are declining, with prematurity and congenital anomalies being leading causes of neonatal death. Current reporting frameworks lack granularity, and a wider adoption of standardized classification systems is critical to improving surveillance and data comparability, especially for preterm infants.What is Known:• Neonatal mortality rates have declined across Europe over recent decades.• There are considerable regional disparities in both causes and rates of neonatal death.What is New:• Prematurity and congenital anomalies each account for ~30% of neonatal deaths.• Greater use of standardized classifications of neonatal death causes is urgently needed.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00431-025-06467-0.

European regions with a lower population density have greater structural difficulties in ensuring that the daily life of their inhabitants matches that of more populated regions. This problem persists in groups of people who present some type of disability. Soria (Spain) is one of such regions. It is considered the most depopulated region of Southern Europe. Therefore, the aim of this study was to analyse the reality of people with disabilities in one of the provinces with a lower population density. It also seeks to explore the relationship between the perceptions and the reality of the existing structure to infer the promotions or limitations of agency. To this end, we conducted a systematic review of the existing literature, a sociogeographic study of the study context, and a mixed investigation. The results show that the greatest problem lies in the cities and towns located far away from the capital city, causing budget cutbacks and, therefore, reducing the attention to the needs of people with disabilities. However, social solidarity has increased, which is perceived as greater social inclusion for this group.

Allocation of larval nutrients affects adult life history traits in insects. This study assessed the effect of moth age and wing loading on flight capacity in an outbreaking forest lepidopteran, Malacosoma disstria Hübner . Insects were collected from high and low density populations after larval feeding, and flight capacity was tested directly with flight mills and indirectly through the allometric relationship between wing area and body size. Insects from these same populations collected as eggs and fed with a synthetic diet in the laboratory were tested in a separate experiment. Male moth propensity to fly increased with wing loading only when moths were collected as pupae after feeding in the field at high population densities. Moth age and wing loading did not affect the distance flown by male moths in any of the population density-nutrient regime combinations tested. Energy use increased with flight distance in both experiments. The slope of the allometric relationship between wing area and body mass did not differ from isometry when moths were collected as pupae after feeding at low and high population densities in the field. The slope of this relationship was steeper for males collected from high than low population densities. There was no allometric relationship between wing area and body mass of moths collected from these same populations as eggs and fed ad libitum in the laboratory as larvae. The results suggest that male M. disstria can allocate resources to different life history traits in response to differences in population density.