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Background/aim: Intercity travel is one of the most important parameters for combating a pandemic. The ongoing COVID-19 pandemic has resulted in different computational studies involving intercity connections. In this study, the effects of intercity connections during an epidemic such as COVID-19 are evaluated using a new network model. Materials and methods: This model considers the actual geographic neighborhood and population density data. This new model is applied to actual Turkish data by means of provincial connections and populations. A Monte Carlo algorithm with a hybrid lattice model is applied to a lattice with 8802 data points. Results: Around Monte Carlo step 70, the number of active cases in Türkiye reaches up to 8.0% of the total population, which is followed by a second wave at around Monte Carlo step 100. The number of active cases vanishes around Monte Carlo step 160. Starting with İstanbul, the epidemic quickly expands between steps 60 and 100. Simulation results fit the actual mortality data in Türkiye. Conclusion: This model is quantitatively very efficient in modeling real-world COVID-19 epidemic data based on populations and geographical intercity connections, by means of estimating the number of deaths, disease spread, and epidemic termination. [ABSTRACT FROM AUTHOR]

Over the past several decades, the Gulf of Maine has experienced significant socio‐ecological change. Coastlines have become more densely populated and developed, rapid and dramatic climate change has affected coastal ocean environments, and seal populations have grown as a result of federal protections. Long‐term data sets from marine mammal stranding networks represent a valuable resource for investigating indicator species for coastal ocean health during this period of change. Using data collected from stranded harbor (Phoca vitulina), harp (Pagophilus groenlandicus), and gray (Halichoerus grypus) seals from 2002 to 2017 in Massachusetts, New Hampshire, and Maine, we tested for spatiotemporal correlations between stranding density and human population density, size of and proximity to seal haul‐outs, sea surface temperature, North Atlantic Oscillation, snowfall, and sea ice extent. We found that in the Gulf of Maine proximity to coastal human population centers and large seal haul‐outs are the greatest drivers of reported seal stranding density. Environmental factors played an important role only for harp seals, which do not breed in the study area, although recent shifts in the environmental seascape have the potential to affect all seal species in the Gulf of Maine. [ABSTRACT FROM AUTHOR]

Leafy vegetables are common components of the human diet and are a source of antioxidant, vitamins, minerals, and bioactive compounds. Fresh-cut or minimally processed industries are always looking for product innovations. Many wild species, based on their composition, can be evaluated as potential vegetables. In this work, hedge mustard has been studied as a potential leafy vegetable, and two wild populations were grown under 100% crop water requirement (WR) and 50% WR. The effect of water reduction was monitored using non-destructive measurements of chlorophyll a fluorescence and by the analytical determination of primary or secondary metabolism associated parameters such as sugars, anthocyanins, carotenoids, phenolic compounds, and nitrate concentrations. The results demonstrated that hedge mustard [Sisymbrium officinale (L.) Scop.] can be grown with 50% WR without yield reduction. The yield was not statistically different between the two water regimes and ranged from 22.3 to 40 g plant−1 FW. Leaf nitrate concentrations showed high variability in the MI population grown with 100% WR, while in the BG population, they did not change when the WR was shifted from 100% to 50%. The total phenols were 25% higher in the leaves of plants grown under 50% WR in both wild populations. The total sugars and anthocyanins did not show significant variations. Chlorophyll a fluorescence parameters did not show significant changes. The results suggest that hedge mustard can be grown in environments with limited water availability or in the winter season using less water to avoid disease development. The highest yield was obtained from the BG population. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Neotropical Mammalogy / Mastozoologia Neotropical is the property of Sociedad Argentina para el Estudio de los Mamiferos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Territories are typically defined as spatially exclusive areas that are defended against conspecifics. Given the spatial nature of territoriality, it is inherently density dependent, but the economics of territoriality also depend on the distribution and abundance of defended resources. Our objectives were to assess the effects of changing population density and food availability on individually based territorial phenotypes.We developed a novel analytical framework that bridges spatially explicit territories with social network analysis to model density‐dependent territorial phenotypes. Using the outputs from our data pipeline, we modelled plasticity in territory size and territory intrusion rates in a long‐term study population of North American red squirrels Tamiasciurus hudsonicus. Red squirrels defend year‐round territories around a central hoard (midden) of white spruce Picea glauca cones. Importantly, white spruce is a masting species that produces large cone crops every 4–7 years (i.e. mast years) in our study area interspersed with non‐mast years when few cones are produced. In the spring following mast years, populations are approximately double in size, but are lower in the spring of non‐mast years.We predicted that territory size and intrusion rates would decrease as resource abundance, and consequently population density, increased. By contrast, as resource abundance decreased via depletion, and therefore density decreased, territories should increase in size and intrusions should also increase.As we expected, individual territory size and territorial intrusions were negatively density dependent, such that increased density after mast years resulted in smaller territories and fewer intrusions. When considering between‐individual variation in plasticity across a density gradient, individuals responded differently to changes in population density within their lifetime.Our results show that territory size and intrusion rates display negative density dependence. When food becomes available in the autumn of a mast year and density in spring of the following year increases, territories shrink in size to effectively a small area around the midden. While our findings for red squirrels are unique compared to other systems, they serve as a reminder that the direction and strength of fundamental ecological relationships can depend on the nature of the system. [ABSTRACT FROM AUTHOR]

Population density is important spatial information for addressing the use and access to land resources in cities under the Sustainable Development Goals. This is because the spatial data support appropriate spatial policies at the spatial scale and predicts how much land will be consumed in the future. The study aims to compare and evaluate the regression tools in the context of estimating the population density difference. The three analysis tools used are Random Forest-Based Classification, Multiple Linear Regression, and Geographically Weighted Regression. The sampling area covers cities around Türkiye. Comparative results showed that the two most important descriptive variables in the Random Forest-Based Classification model are the density difference of the new developed area and the connectivity. The three main explanatory variables of the Multiple Linear Regression model are centrality, vehicle ownership, and accessibility. The results of the Multiple Linear Regression model (a non-spatial model) and the Geographically Weighted Regression model (a spatial model), were found to be quite similar. The importance of accessibility and connectivity is more evident in the Multiple Linear Regression model when the Random Forest-Based Classification model highlights the density values in the new development areas. [ABSTRACT FROM AUTHOR]

Internal fertilization and viviparity are characteristic of some species of the genus Sebastes. Some species of this genus were shown to have polyandry. Using five microsatellite markers and three main statistical approaches, the level of polyandry in wild population of white-edged rockfish (Sebastes taczanowskii) was estimated. In some clutches, multiple paternity was detected. This study is the first evidence of multiple paternity in the white-edged rockfish. It seems likely that polyandry is a very common strategy in this species living in the Far Eastern seas, as well as an important factor in the regulation of genetic diversity and productivity. [ABSTRACT FROM AUTHOR]

Copyright of Libellula is the property of Gesellschaft Deutschsprachiger Odonatologen e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Costelytra giveni is a serious pasture pest in New Zealand and accurate estimates of population densities are important to inform control measures. This species generally has a one-year life cycle so populations should either remain stable after eggs have hatched or decline due to larval mortality. Larval counts were obtained using a simple, standard and widely used sampling method from a series of soil cores collected from ryegrass research plots in Canterbury, New Zealand between 27 January and 16 June 2021 and a significant increase in population was recorded. Measurements on 27 January, 19 March and 5 May, represented only c. 8%, 25% and 63% of the mean densities measured on 16 June, respectively. The apparent increase in larvae is attributed to failure to find small 1st and 2nd instar individuals within the soil samples. Larvae increased in size as they transitioned from 1st to 3rd instar and later instar specimens were more easily discovered. An equation to describe the observed results provided date-related correction factors to allow a more realistic prediction of C. giveni larval densities in the winter following empirical larval counts. Larval counts measured on 27 January, 19 March, and 5 May, would need to be multiplied by 13, 4 and 1.6, respectively, to accurately estimate the larval density found on 16 June. This study showed that summerautumn sampling using the current method can significantly underestimate winter C. giveni larval densities, potentially leading to unanticipated pasture production losses. Similar results were also found in 2022. While the equation provides a guide to population estimates, the caveat is that region and environment will influence population trends in any particular year. [ABSTRACT FROM AUTHOR]

Understanding population trends is key to planning and adapting conservation measures for threatened species. A number of conservation and management actions have been implemented to control deforestation and the illegal pet trade in the Caldas department of Colombia in the range of the white-footed tamarin Oedipomidas leucopus1 (Vulnerable A4cd), and we have have monitored their population densities to evaluate the effectiveness of these interventions. Localities in different vegetation composition and management regimes were selected for population monitoring, using the estimated population of the silvery-brown tamarin as an indicator. In 2021, new population density estimates were obtained and compared with previous estimates from 2006–2008 and 2015. In this recent re-surveying, population densities found in the eastern Caldas region were between 18 and 129 individuals/km². No changes were found in four localities when compared to the previous surveys. In one locality there was an increase in population density from 76 to 129 ind/km². We were unable to survey one previously surveyed, so a new location was included. Our data suggest that measures to control the pet trade of this primate have been successful in this zone. We also evaluated population density differences in the distinct ecosystems: humid lowland forest; humid sub-Andean Forest, and humid lowland secondary vegetation. The population densities differed between the three ecosystems—the population density was higher in the sub-Andean humid forest. [ABSTRACT FROM AUTHOR]

We assessed the population sizes of nocturnal lemur species within Bemanevika Protected Area (PA) in the northern highlands of Madagascar from October to December 2019. We used the Transect Distance Sampling method for counting nocturnal lemur species along six permanent transects in the three largest forest blocks of Andriakanala, Matsaborimaitso and Matsaborimena. We surveyed each transect line during three consecutive nights from 18:00 to 22:00. We also carried out capturereleases in order to verify species of the Cheirogaleidae family through morphological parameters. Our findings showed that the three forest blocks had at least 117 individuals belonging to five threatened nocturnal species of lemurs: Allocebus trichotis (EN), Cheirogaleus major (VU), Microcebus sambiranensis (EN), Lepilemur dorsalis (EN) and Avahi unicolor (CR). The Cheirogaleidae family was represented by A. trichotis, C. major and M. sambiranensis based on morphological measurement. Relative lemur abundance was highest in C. major with 39.68 %, whilst M. sambiranensis and A. trichotis were 33.98 % and 5.28 %, respectively. The estimated population density range of C. major was 68 - 131 ind/km2, 144 - 202 ind/km2 for M. sambiranensis and 13 - 23 ind/km2 for A. trichotis. Only the density of M. sambiranensis and C. major showed a statistically significant variation between forest blocks. This study provides information on the current population size of nocturnal lemur species and their distribution throughout three forest blocks in Bemanevika PA, especially for the Cheirogaleidae. Daubentonia madagascariensis was not observed, although signs of its presence were reported. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) is an infectious disease that affects both domestic pigs (DPs) and wild boar (WB). The WB population plays an important role in the spread of ASF as the WB acts as a natural reservoir of the virus and transmits it to other susceptible wild and domestic pigs. Our study was aimed at revealing the areas with a high concentration of the WB population, and their potential relationships with the grouping of ASF cases in WB during the course of the ASF spread in the Russian Federation (2007–2022). We collected the annual data on WB numbers by municipalities within the regions of the most intensive ASF spread. We then conducted spatiotemporal analysis to identify clustering areas of ASF cases and compare them with the territories with a high density of WB population. We found that some of the territories with elevated ASF incidence in WB demonstrated spatial and temporal coincidence with the areas with a high WB population density. We also visualized the zones (“emerging hot spots”) with a statistically significant rise in the WB population density in recent years, which may be treated as areas of paramount importance for the application of surveillance measures and WB population control.

Yaku sika deer (Cervus nippon yakushimae) are endemic to Yakushima Island, whose landscape covered with primary evergreen forest is recognized as a World Heritage Site. In this study, the rumen bacterial microbiota (RBM) of wild Yaku sika was characterized using high throughput sequencing of bacterial 16S rRNA genes combined with targeted cultivation and functional analyses. Comparative analyses of RBM datasets from other ruminant animals revealed distinct community structure among domesticated and wild ruminants. Wild Yaku sika RBM exhibited higher species richness than other sika deer (i.e. wild Ezo sika and domesticated sika deer), likely reflecting their dietary variations associated with unique ecosystem in the island. The Yaku sika RBM of high deer population density samples exhibited higher diversity and contained higher proportion of Firmicutes than those of lower density samples. Moreover, the highest abundance of tannase gene were observed in individuals from the highest population density area, consistent with the previous observation that Yaku sika in the high density areas expanded their feed to include tannin-rich unpalatable plants. This study indicated that RBM of unique wild Yaku sika contribute to the flexibility of dietary shift and thus maintaining nutritional status of Yaku sika under high density conditions. [ABSTRACT FROM AUTHOR]

Many ecological questions can be answered only with data from hundreds or even thousands of individuals. In some taxonomic groups, such as snakes, the availability of those data is rare due to low population densities and/or the difficulties in collecting them. Hence, studies on the population structure of snakes are still relatively scarce compared to other zoological groups. In this study, we had the opportunity to analyze the population structure from an unusually large sample of the Pampean water snake Helicops infrataeniatus. The specimens were collected through a flood event caused by excessive rainfall related to an El Niño period in southern Brazil. Although H. infrataeniatus is a common species in the study area, no ecological data regarding its population structure are available so far. Therefore, the main goals of this study were to (1) determine sex ratios, (2) test for sexual dimorphism, and (3) identify the ventral polymorphism in this population. We analyzed 672 individuals (46.4% females, 53.6% males; 50.2% were classified as adults, 48.6% juveniles, and 1.3% hatchlings). The total body length (ToL) ranged from 18.4-77.4 cm for females, and 19.7-67.0 cm for males, tail length (TaL) was 4.5-21.9 cm and 5.8-21.5 cm; sub-caudal scales were 55-73, 74-92, and weight was 2.2-191.0 g, 2.3-93.3 g. Highly significant differences were detected in the number of sub-caudal scales and the TaL:ToL ratios between females vs. males tested via analysis of covariance (ANCOVA), suggesting the presence of sexual dimorphism. Regarding the ventral spotting patterns, 38.0% of individuals had trilinear, 36.0% - intermediate, and 26.0% - checkered color patterns. Besides this, 63.0% of the individuals had a reddish ventral coloration, 25.0% - yellowish, and 12.0% - both colors. No correlation was found between ventral polymorphism and sex or age class. The results presented herein offer the first robust snapshot of the population structure of H. infrataeniatus. [ABSTRACT FROM AUTHOR]

Climate is a major extrinsic factor affecting the population dynamics of many organisms. The Broad‐Scale Climate Hypothesis (BSCH) was proposed by Elton to explain the large‐scale synchronous population cycles of animals, but the extent of support and whether it differs among taxa and geographical regions is unclear. We reviewed publications examining the relationship between the population dynamics of multiple taxa worldwide and the two most commonly used broad‐scale climate indices, El Niño‐Southern Oscillation (ENSO) and North Atlantic Oscillation (NAO). Our review and synthesis (based on 561 species from 221 papers) reveals that population changes of mammals, birds and insects are strongly affected by major oceanic shifts or irregular oceanic changes, particularly in ENSO‐ and NAO‐influenced regions (Pacific and Atlantic, respectively), providing clear evidence supporting Elton's BSCH. Mammal and insect populations tended to increase during positive ENSO phases. Bird populations tended to increase in positive NAO phases. Some species showed dual associations with both positive and negative phases of the same climate index (ENSO or NAO). These findings indicate that some taxa or regions are more or less vulnerable to climate fluctuations and that some geographical areas show multiple weather effects related to ENSO or NAO phases. Beyond confirming that animal populations are influenced by broad‐scale climate variation, we document extensive patterns of variation among taxa and observe that the direct biotic and abiotic mechanisms for these broad‐scale climate factors affecting animal populations are very poorly understood. A practical implication of our research is that changes in ENSO or NAO can be used as early signals for pest management and wildlife conservation. We advocate integrative studies at both broad and local scales to unravel the omnipresent effects of climate on animal populations to help address the challenge of conserving biodiversity in this era of accelerated climate change. [ABSTRACT FROM AUTHOR]

Reeves' turtle (Mauremys reevesii) originated in China and was once one of the most widely distributed and abundant hard-shelled turtles in China; however, overharvesting has led to a sharp decline in its wild populations. A survey of Reeves' turtle was conducted from July 2021 to March 2022 in Qichun County, Hubei Province, China. A total of 74 individuals were caught in 26 ponds (1078 trap-days), indicating a catch effort population density of 0.07 individuals/trap-day. The 840 similar ponds in the field-surveyed towns indicate a population number of 2391 individuals and density of 4 individuals/km2. Our preliminary results suggest that Reeves' turtle populations face serious threats from human hunting activities, habitat destruction, and artificial release and urgently require an aggressive conservation program to ensure their survival. [ABSTRACT FROM AUTHOR]

This paper analyses age-specific migration exchange between municipal formations (MFs) in Russia based on the net migration and population density data covering the period 2012–2018. Unlike many other developed countries, Russia's population concentrates in only 2–5% of the country's territory—in large cities and their suburbs. We utilise population density as an alternative measure for distinguishing between urban and rural populations (which is a formal distinction in most cases) in the urban–rural continuum. The results indicate that internal migration pattern in Russia corresponds to the urbanisation stage of the urban development model and is observed across all age groups. Net migration across all age groups is higher in more densely populated MFs. Migration to more densely populated territories peaks in the 15–19 age group and seems to have no viable alternative directions. Besides the analysis of internal migration role in the urban development patterns in Russia, the paper also contributes to a better understanding of the relationship between age-specific migration and urban development in the Russian context. [ABSTRACT FROM AUTHOR]

Anthropogenic land‐use change continues to be predicated as a major driver of terrestrial biodiversity loss for the rest of this century. It has been determined that the effect of climate change on wildlife population will accelerate the rate and process of decline of global vertebrate populations. We investigated wildlife composition, occupancy, and activity pattern along the larger climate resilient forests that serve as microrefugia for a wide range of species under the escalating climate change. We used camera trap survey covering 250 km2 of climate microrefugia in Dadeldhura hills in far western region of Nepal. We used 62 trapping locations accumulating 1800 trap nights taking 98,916 photographs in 62 days‐survey period during the summer season of 2020. We photographed 23 mammalian species with estimated species richness of 30 species (95% CI: 25–34) based on multi‐species occupancy model. We estimated overall species occupancy ψ(SE(ψ)) to be 0.87 (0.09) in climatic microrefugia. While human activity predominated throughout the day, the majority of animals was found to exhibit nocturnal temporal patterns. Tiger and hyaena, two of the top predators, were newly discovered in the western Himalayan range of Nepal, with their discovery at the 34 highest elevations of 2511 meters and 2000m, respectively. In Nepal, high‐altitude tiger range is characterized by tiger distribution above a 2000 m cutoff representing habitats in the physiographic zone of high mountains and above. Our findings establish a baseline and show that the climatic microrefugia that have been identified have high levels of species richness and occupancy, which characterize the Dadeldhura hill forest ranges as biologically varied and ecologically significant habitat. These areas identified as climatic microrefugia habitats should be the focus of conservation efforts, particularly efforts to reduce human disturbance and adapt to climate change. [ABSTRACT FROM AUTHOR]

Measuring individual fitness empirically is required to assess selective pressures and predicts evolutionary changes in nature. There is, however, little consensus on how fitness should be empirically estimated. As fitness proxies vary in their underlying assumptions, their relative sensitivity to individual, environmental, and demographic factors may also vary. Here, using a long‐term study, we aimed at identifying the determinants of individual fitness in bighorn sheep (Ovis canadensis) using seven fitness proxies. Specifically, we compared four‐lifetime fitness proxies: lifetime breeding success, lifetime reproductive success, individual growth rate, individual contribution to population growth, and three multi‐generational proxies: number of granddaughters, individual descendance in the next generation, and relative genetic contribution to the next generation. We found that all proxies were positively correlated, but the magnitude of the correlations varied substantially. Longevity was the main determinant of most fitness proxies. Individual fitness calculated over more than one generation was also affected by population density and growth rate. Because they are affected by contrasting factors, our study suggests that different fitness proxies should not be used interchangeably as they may convey different information about selective pressures and lead to divergent evolutionary predictions. Uncovering the mechanisms underlying variation in individual fitness and improving our ability to predict evolutionary change might require the use of several, rather than one, the proxy of individual fitness. [ABSTRACT FROM AUTHOR]

The ecology of zoonotic, including vector-borne, diseases in urban social-ecological systems is influenced by complex interactions among human and environmental factors. Several characteristics contribute to the emergence and spread of infectious diseases in urban places, such as high human population densities, favorable habitat for vectors, and humans' close proximity to animals and their pathogens. On the other hand, urban living can contribute to the improvement of public health through better access to health services and creation of ecological and technological infrastructure that reduces disease burdens. Therefore, urbanization creates a disease ecology paradox through the interplay of urban health penalties and advantages for individual and community outcomes. To address this contradiction, we advocate a holistic Urban One Health perspective for managing urban systems, especially their green spaces and animal populations, in ways that more effectively control the spread of zoonotic diseases. This view should be coupled with an Ecology with Cities approach which emphasizes actionable science needed for urban planning, management and policymaking; developing disease and vector surveillance programs using citizen and community science methods; and improving education and communication actions that help diverse stakeholders understand the complexities of urban disease ecology. Such measures will enable scholars from many disciplines to collaborate with professionals, government officials, and others to tackle challenges of the urban disease paradox and create more sustainable, health-promoting environments. [ABSTRACT FROM AUTHOR]

Understanding how ecological processes combine to shape population dynamics is crucial in a rapidly changing world. Evidence has been emerging for how fundamental drivers of density dependence in mobile species are related to two differing types of environmental variation—temporal variation in climate, and spatiotemporal variation in food resources. However, to date, tests of these hypotheses have been largely restricted to mid‐trophic species in terrestrial environments and thus their general applicability remains unknown.We tested if these same processes can be identified in marine upper trophic level species. We assembled a multi‐decadal data set on population abundance of 10 species of colonial seabirds comprising a large component of the UK breeding seabird biomass, and covering diverse phylogenies, life histories and foraging behaviours.We tested for evidence of density dependence in population growth rates using discrete time state‐space population models fit to long time‐series of observations of abundance at seabird breeding colonies. We then assessed if the strength of density dependence in population growth rates was exacerbated by temporal variation in climate (sea temperature and swell height), and attenuated by spatiotemporal variation in prey resources (productivity and tidal fronts).The majority of species showed patterns consistent with temporal variation in climate acting to strengthen density dependent feedbacks to population growth. However, fewer species showed evidence for a weakening of density dependence with increasing spatiotemporal variation in prey resources.Our findings extend this emerging theory for how different sources of environmental variation may shape the dynamics and regulation of animal populations, demonstrating its role in upper trophic marine species. We show that environmental variation leaves a signal in long‐term population dynamics of seabirds with potentially important consequences for their demography and trophic interactions. [ABSTRACT FROM AUTHOR]

Effect of density-independent factors (minimum–maximum temperatures and relative humidity) and density dependant factors ( plant age and natural enemies; Coccinella undecimpunctata, Chrysoperla carnea, Syrphus corolla, Eretmocerus eremicus and Orius laevigatus) of the environment on the population dynamics of Silverleaf whitefly, Bemisia tabaci (Genn.) and potato leaf hopper, Empoasca fabae (Harris) attacking potato plant Solanum tuberosum at El-Gharbia governorate, Egypt were investigated on autumn and spring plantation of 2019/2020 &2020/2021 seasons. The results revealed that the population fluctuation of B. tabaci & E. fabae recorded the highest infestation in December during both autumn seasons, while in both spring seasons the highest peak for the two pests was reached in May. The combination of abiotic and biotic environmental factors on population densities of B. tabaci and E. fabae was effective as the explained variance (E.V.) values were (88% - 92%) and (85% - 86%) for B. tabaci, while E.V. was (94% _ 91%) and (92% - 77%) for E. fabae during autumn and spring of the plantation 2019/2020 &2020/2021 seasons, respectively. The present research can be helpful to the ecological characteristics of main potato pests to obtain more effective pest management. [ABSTRACT FROM AUTHOR]

Early‐life environmental conditions can provide a source of individual variation in life‐history strategies and senescence patterns. Conditions experienced in early life can be quantified by measuring telomere length, which can act as a biomarker of survival probability in some species. Here, we investigate whether seasonal changes, weather conditions and group size are associated with early‐life and/or early‐adulthood telomere length in a wild population of European badgers (Meles meles). We found substantial intra‐annual changes in telomere length during the first 3 years of life, where within‐individual effects showed shorter telomere lengths in the winter following the first spring and a trend for longer telomere lengths in the second spring compared to the first winter. In terms of weather conditions, cubs born in warmer, wetter springs with low rainfall variability had longer early‐life (3–12 months old) telomeres. Additionally, cubs born in groups with more cubs had marginally longer early‐life telomeres, providing no evidence of resource constraint from cub competition. We also found that the positive association between early‐life telomere length and cub survival probability remained when social and weather variables were included. Finally, after sexual maturity, in early adulthood (i.e., 12–36 months) we found no significant association between same‐sex adult group size and telomere length (i.e., no effect of intrasexual competition). Overall, we show that controlling for seasonal effects, which are linked to food availability, is important in telomere length analyses, and that variation in telomere length in badgers reflects early‐life conditions and also predicts first year cub survival. [ABSTRACT FROM AUTHOR]

The spotted hyaena ( I Crocuta crocuta i ) is an important carnivore species whose dual role of scavenger and predator is vital to trophic energy flows of systems in which they are found (Cooper, 1990; Kruuk, 1972). Photographs (a,b) and (c,d) respectively, show two individual spotted hyaenas recorded at different camera stations gl Spotted hyaena density estimates for the null (g0 ~ 1), site-specific (g0 ~ k) and time factor (g0 ~ t) population models are given in Table 1. Using by-catch camera trapping data for estimating the population size of spotted hyaenas (Crocuta crocuta) This study successfully derived population estimates of spotted hyaenas at MWR using by-catch data collected from a leopard baited camera trap survey using capture-recapture analysis. [Extracted from the article]

Many animals use the geomagnetic field to migrate long distances with high accuracy; however, research has shown that individual responses to magnetic cues can be highly variable. Thus, it has been hypothesized that magnetoreception alone is insufficient for accurate migrations and animals must either switch to a more accurate sensory cue or integrate their magnetic sense over time. Here we suggest that magnetoreceptive migrators could also use collective navigation strategies. Using agent-based models, we compare agents utilizing collective navigation to both the use of a secondary sensory system and time-integration. Our models demonstrate that collective navigation allows for 70% success rates for noisy navigators. To reach the same success rates, a secondary sensory system must provide perfect navigation for over 73% of the migratory route, and time integration must integrate over 50 time-steps, indicating that magnetoreceptive animals could benefit from using collective navigation. Finally, we explore the impact of population loss on animals relying on collective navigation. We show that as population density decreases, a greater proportion of individuals fail to reach their destination and that a 50% population reduction can result in up to a 37% decrease in the proportion of individuals completing their migration. [ABSTRACT FROM AUTHOR]

Understanding how weather conditions affect animal populations is essential to foresee population changes in times of global climate shifts. However, assessing year-round weather impacts on demographic parameters is hampered in migratory animals due to often unknown occurrence in space and time. We addressed this by coupling tracking and weather data to explain extensive variation in apparent survival across 19 years in a northern European population of little ringed plovers (Charadrius dubius). Over 90% (n = 21) of tracked individuals followed migration routes along the Indo-European flyway to south India. Building on capture–recapture histories of nearly 1400 individuals, we found that between-year variation in precipitation during post-breeding staging in northern South Asia explained 47% of variation in apparent adult survival. Overall, the intensity of the monsoon in South Asia explained 31–33% of variability in apparent survival. In contrast, weather conditions in breeding, final non-breeding and pre-breeding quarters appeared less important in this species. The integration of multi-source data seems essential for identifying key regions and periods limiting population growth, for forecasting future changes and targeting conservation efforts. [ABSTRACT FROM AUTHOR]

As global temperatures continue to rise, population or spatial synchrony (i.e., the degree of synchronization in the fluctuation of demographic parameters) can have important implications for inter- and intraspecific interactions among wildlife populations. Climatic fluctuations are common drivers of spatial synchrony, and depending on the degree of synchronization and the parameters impacted, synchrony can increase extinction probabilities. Although citizen science is an inexpensive method to collect long-term data over large spatial scales to study effects of climate changes on wildlife, few studies have used citizen science data to determine if this synchrony is occurring across populations and species. We used 21 years of citizen science nesting data collected on Eastern Bluebirds (Sialia sialis) and Carolina Chickadees (Poecile carolinensis), two widespread North American species with similar life histories and abundant data, to assess the degree of synchrony between and within their populations in the southeastern United States. We found little evidence of synchronous fluctuations in the nesting parameters of hatching success, hatchability, and fledging success between and within species, nor did we observe consistent patterns towards increased or decreased synchrony. Estimates of nesting parameters were high (≥ 0.83) and showed little variability (relative variance ≤ 0.17), supporting the hypothesis that parameters that strongly contribute to population growth rates (i.e., typically fecundity in short-lived species) show little interannual variability. The low variability and lack of synchrony suggest that these populations of study species may be resilient to climate change. However, we were unable to test for synchronous fluctuations in other species and populations, or in the survival parameter, due to large gaps in data. This highlights the need for citizen science projects to continue increasing public participation for species and regions that lack data. [ABSTRACT FROM AUTHOR]

Deer overpopulation is a major threat to forest ecosystems worldwide resulting in loss of natural vegetation cover and increased sapling mortality. To resolve this problem of deer overpopulation, different strategies such as deer exclusion and gap creation have been explored to determine more efficient methods to restore deer-damaged forest ecosystems. In the current study, we applied a 2x2 factorial design of four different treatment groups in warm temperate secondary forests: closed canopy with deer as control, closed canopy without deer, clearcut with deer and clearcut without deer. We compared the decadal change in tree foliar cover and tree species richness among treatment groups to assess tree regeneration success. We also selected six tree species (Abies firma, Quercus acuta, Eurya japonica, Cinnamomum tenuifolium, Castanopsis sieboldii and Neolitsea sericea) that are common in the studied region and compared their regeneration success among the treatment groups. In the absence of deer, clearcutting increased the diversity of tree species and accelerated sapling growth, while under closed canopy conditions sapling heights did not exceed two meters. Tree saplings tended to be less abundant in treatments with deer compared to their counterpart, suggesting limited successful recruitment of saplings at the current deer density (10-13.5 deer km2). In clearcut-with-deer treatment, non-tree species became abundant, and negatively affected recruitment of tree species as was suggested by regression analysis. However, these general trends were not equal for all tree species. Although clearcut-without-deer treatment facilitated sapling recruitment of all six tree species, Q. acuta, C. tenuifolium and C. sieboldii required deer exclusion for sapling recruitment while A. firma, N. sericea and E. japonica required increased light availability. Consequently, informed decisions can be made by identifying whether certain tree species are capable of naturally recruiting without human intervention and how best to ensure successful recruitment if necessary. By implementing effective strategies, time and resources will be saved, and management goals such as reestablishing tree cover rapidly and increasing tree species diversity can be achieved. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Fisheries & Aquatic Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To feed the world population while mitigating pressing nitrogen (N) pollution problems, tremendous efforts have been devoted to developing and implementing N‐efficient technologies in crop or livestock production, but limited progress has been made. The N management improvement on a farm does not necessarily translate to N pollution reduction on a broader scale due to complex responses of natural and human systems and lack of coordination among stakeholders. Consequently, it is imperative to develop an N management framework that encompasses the complex N dynamics across systems and spatial scales, yet simple enough to guide policies and actions of various stakeholders. Here, we propose a new framework, CAFE, that defines four N management systems (Cropping, Animal‐crop, Food, and Ecosystem) in a hierarchical manner, and apply it to 13 representative countries to partition N surpluses across systems in a simple and consistent manner, thereby facilitating the identification and prioritization of systems‐based intervention strategies. Surprisingly, the Cropping system contributes less than half of the total N surplus within its Ecosystem for most countries, highlighting the importance of N management beyond croplands. This framework reveals that the relevant priorities and key stakeholders for enhanced N management vary among countries, such as improving the Cropping‐system efficiencies in China, adjusting the animal‐crop portfolio in the Netherlands, reducing food wastage in the U.S., and lowering crop storage losses and increasing overall production capacities in African countries. As N surplus increases along the CAFE hierarchy, systems‐based intervention strategies are revealed: (a) coupling chemical fertilizers with other N sources by maintaining half of the N from manure and biological N fixation; (b) coupling animal‐crop production by reducing animal density to lower than 1.2 livestock units per hectare, and increasing self‐sufficiency of animal feed to above 50%; (c) coupling food trade with domestic demand and production; and (d) coupling population needs for economic opportunities with environmental capacity of the region. This novel framework can help unpack the "wicked" N management challenges across systems to provide new insights and tools for improving N management on and beyond farms. Plain Language Summary: To tackle the "wicked" nitrogen (N) challenge, N‐efficient technologies in crop or livestock production alone are insufficient. A broader understanding of the complex dynamics and interactions across different N cycle systems and among various stakeholders is needed. We propose a new framework, CAFE, that defines four N management systems (Cropping system, Animal‐crop system, Food system, and landscape Ecosystem) in a hierarchical manner, and the quantitative relations represented by N surplus changes between adjacent CAFE systems are illustrated. Potential driving factors for N surplus increases across the CAFE systems are also identified, such as animal and population density, feed and food self‐sufficiency, etc. This framework can be used to partition N surpluses across systems and spatial scales in a simple and consistent manner, thereby facilitating the identification and prioritization of systems‐based intervention strategies. Applying CAFE to 13 representative countries reveals that the cropping system contributes to less than half of the total N surplus of its respective ecosystem for most countries, highlighting the importance of N management beyond croplands, and the relevant priorities and key stakeholders for enhanced N management vary among countries. Potential systems‐based intervention strategies are proposed with new insights for achieving sustainable N management. Key Points: Cropping, Animal‐crop, Food, and Ecosystem framework encompasses the complex N dynamics across systems and spatial scales to guide policiesPriorities and key stakeholders for enhanced N management vary among countriesSystematic solutions that improve the coupling of different system components were revealed [ABSTRACT FROM AUTHOR]

Spatially explicit capture–recapture modeling is used to estimate population density to enhance our ecological understanding and management of wildlife populations. The two primary parameters estimated in the capture process of these models are σ and g0. The σ parameter is the standard deviation of a bivariate normal home range kernel (indicating home range size), while g0 is the probability of capture by a device placed at the home range center. These parameters are being increasingly generalized and used in simulation models to predict the detection or capture rates of invasive animals to inform management strategies. Given the sensitivity of simulation model predictions to parameter values, we performed an analysis of preexisting GPS telemetry and trapping data of invasive brushtail possums (Trichosurus vulpecula) across New Zealand to address the following three questions. First, how does σ vary with population density, habitat, and age–sex class? Second, how is g0 influenced by home range size (i.e., σ) and trap type? Third, how does the predicted probability of capture or detection of individuals vary with σ, different trap types and trap densities? We used data from 180 possums across 18 sites to develop a Bayesian hierarchical model. Results showed that σ decreased with increasing population density and increasing area of productive grassland. There was a strong negative relationship between σ and g0, and g0 was highest for cage traps and lowest for raised leg‐hold traps. Despite the potential compensatory inverse effect of g0 with σ, the probability of capturing a randomly located possum by a large array of traps increased with increasing σ. Results show that selection of σ for predictive simulation modeling should begin with an estimated population density. The associated g0 should then be identified as a function of σ, and stochasticity should be incorporated to account for inter‐individual variability. The approach employed here provides a methodology for estimating density, σ, and g0 using trapping and telemetry data, and our results will help guide careful consideration of density, σ, and g0 to improve the accuracy of simulation studies across species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wildlife conservation and management need accurate methods for population survey and monitoring. Absolute counts of roe deer populations (Capreolus capreolus) are not possible, but the rapid advancement of motion‐sensitive camera technologies and new analytical approaches might potentially lead to more precise estimates at lower costs compared to traditional survey methods. We applied spatially explicit photographic capture–recapture models (SCR) in the Lake Geneva basin, Switzerland, from 25 April to 20 September 2018 to estimate roe deer densities in a pilot survey. We investigated the effect of survey duration and camera density on male roe deer density estimates to select the sampling design that produced density estimates with sufficient accuracy and precision at lower costs (i.e., material, fieldwork, data processing, and analyses). Males could be identified based on their antlers, which allowed us to apply SCR to estimate their density. Because females could not be identified individually, we inferred the overall roe deer density (adult and sub‐adult roe deer) based on the sex ratio estimated from motion‐sensitive camera photos. According to the results of sub‐sampling simulations and by taking into account the financial costs associated with fieldwork and analyses, we conclude that 20 motion‐sensitive cameras set over 20 nights (i.e., the 20/20 method) is a good compromise to provide reliable estimates of male roe deer density. Furthermore, studies estimating overall roe deer density using SCR and sex ratio estimates should be conducted from mid‐August to the end of October just after rutting season and the peak of yearling dispersal, when the movement rates of males and females, and hence their detection probabilities, are similar and when males are still carrying their antlers. This approach was successfully applied in 4 selected study areas with contrasting roe deer management regimes, resulting in overall roe deer density estimates ranging from 3.9 ± 1.3 (SE) deer/km2 forest to 22.5 ± 6.1 deer/km2 forest. Our study provides a valuable and cost‐effective approach using photographic SCR methodology and sex ratio information to calculate roe deer density estimates that can be used in management measures such as defining hunting quotas. [ABSTRACT FROM AUTHOR]

Assessing the conservation status of species is essential for implementing appropriate conservation measures. A lack of evidence of threats, rather than showing an absence of impacts, could reflect a lack of studies on how human activities could result in species population declines. The range of Prince Bernhard's titi monkey Plecturocebus bernhardi is restricted to the Arc of Deforestation, a deforestation hotspot in south-eastern Amazonia. Despite this, it is categorized as Least Concern on the IUCN Red List. To reassess the conservation status of P. bernhardi , we carried out surveys during 2015–2017 to delimit the geographical distribution of the species and estimate its population density and abundance. We then used spatial predictive modelling to examine future habitat and population loss within its range. Plecturocebus bernhardi occurs over an area of 131,295 km2. Its mean group size was 2.8 individuals/group and its density 10.8 individuals/km2 and 3.8 groups/km2. Habitat loss was estimated to be 58,365 km2 (44.5% of its current range) over the next 24 years (three P. bernhardi generations) under a conservative governance model of deforestation and 105,289 km2 (80.2%) under a business-as-usual model. These numbers indicate that P. bernhardi is threatened and should be categorized as Vulnerable, at least, using the IUCN Red List criteria. We recommend the reassessment of other Least Concern primate species from the Arc of Deforestation using a similar approach. [ABSTRACT FROM AUTHOR]

Retrospective comparison of predictive models that describe competing hypotheses regarding system function can shed light on regulatory mechanisms within the framework of adaptive resource management. We applied this approach to a 28‐year study of red grouse (Lagopus lagopus scotica) in Scotland, with the aims of reducing uncertainty regarding important drivers of grouse population dynamics, and of evaluating the efficacy of using seasonal versus annual model assessments. We developed three sets of models that predicted pre‐breeding and post‐breeding grouse density, matching the timing of grouse counts on the ground. We updated conditions and management through time in the spirit of a real‐time, adaptive management program and used a Bayesian model weight updating process to compare model predictions with empirical grouse densities. The first two model sets involved single annual updates from either pre‐breeding or post‐breeding counts; the third set was updated twice a year. Each model set comprised seven models representing increasingly complex hypotheses regarding potentially important drivers of grouse: the baseline model included weather and parasite effects on productivity, shooting losses and density‐dependent overwinter survival; subsequent models incorporated the effect of habitat gain/loss (HAB), control of non‐protected predators (NPP) and predation by protected hen harriers (Circus cyaneus, HH) and buzzards (Buteo buteo, BZ). The weight of evidence was consistent across model sets, settling within 10 years on the harrier (NPP + HH), buzzard (NPP + HH + BZ) and buzzard + habitat (NPP + HH + BZ + HAB) models, and downgrading the baseline + habitat, non‐protected predator, and non‐protected predator + habitat models. By the end of the study only the buzzard and buzzard + habitat models retained substantial weights, emphasizing the dynamical complexity of the system. Habitat inclusion failed to improve model predictions, implying that over the period of this study habitat quantity was unimportant in determining grouse abundance. Comparing annually and biannually assessed model sets, the main difference was in the baseline model, whose weight increased or remained stable when assessed annually, but collapsed when assessed biannually. Our adaptive modeling approach is suitable for many ecological situations in which a complex interplay of factors makes experimental manipulation difficult. [ABSTRACT FROM AUTHOR]

Group living in species can have complex consequences for individuals, populations, and ecosystems. Therefore, estimating group density and size is often essential for understanding population dynamics, interspecific interactions, and conservation needs of group‐living species. Spatial capture–recapture (SCR) has been used to model both individual and group density in group‐living species, but modeling either individual‐level or group‐level detection results in different biases due to common characteristics of group‐living species, such as highly cohesive movement or variation in group size. Furthermore, no SCR method currently estimates group density, individual density, and group size jointly. Using clustered point processes, we developed a cluster SCR model to estimate group density, individual density, and group size. We compared the model to standard SCR models using both a simulation study and a data set of detections of African wild dogs (Lycaon pictus), a group‐living carnivore, on camera traps in northern Botswana. We then tested the model's performance under various scenarios of group movement in a separate simulation study. We found that the cluster SCR model outperformed a standard group‐level SCR model when fitted to data generated with varying group sizes, and mostly recovered previous estimates of wild dog group density, individual density, and group size. We also found that the cluster SCR model performs better as individuals' movements become more correlated with their groups' movements. The cluster SCR model offers opportunities to investigate ecological hypotheses relating group size to population dynamics while accounting for cohesive movement behaviors in group‐living species. [ABSTRACT FROM AUTHOR]

Spatial capture–recapture (SCR) models have emerged as a robust method to estimate the population density of mobile animals. However, model evaluation has generally been based on data simulated from simplified representations of animal space use. Here, we generated data from animal movement simulated from a mechanistic individual‐based model, in which movement emerges from the individual's response to a changing environment (i.e., from the bottom‐up), driven by key ecological processes (e.g., resource memory and territoriality). We drew individual detection data from simulated movement trajectories and fitted detection data sets to a basic, resource selection and transience SCR model, as well as their variants accounting for resource‐driven heterogeneity in density and detectability. Across all SCR models, abundance estimates were robust to multiple, but low‐degree violations of the specified movement processes (e.g., resource selection). SCR models also successfully captured the positive effect of resource quality on density. However, covariate models failed to capture the finer scale effect of resource quality on detectability and space use, which may be a consequence of the low temporal resolution of SCR data sets and/or model misspecification. We show that home‐range size is challenging to infer from the scale parameter alone, compounded by reliance on conventional measures of "true" home‐range size that are highly sensitive to sampling regime. Additionally, we found the transience model challenging to fit, probably due to data sparsity and violation of the assumption of normally distributed inter‐occasion movement of activity centers, suggesting that further development of the model is required for general applicability. Our results showed that further integration of complex movement into SCR models may not be necessary for population estimates of abundance when the level of individual heterogeneity induced by the underlying movement process is low, but appears warranted in terms of accurately revealing finer scale patterns of ecological and movement processes. Further investigation into whether this holds true in populations with other types of realistic movement characteristics is merited. Our study provides a framework to generate realistic SCR data sets to develop and evaluate more complex movement processes in SCR models. [ABSTRACT FROM AUTHOR]

Understanding how broad‐scale patterns in animal populations emerge from individual‐level processes is an enduring challenge in ecology that requires investigation at multiple scales and perspectives. Complementary to this need for diverse approaches is the recent focus on integrated modeling in statistical ecology. Population‐level processes represent the core of spatial capture–recapture (SCR), with many methodological extensions that have been motivated by standing ecological theory and data‐integration opportunities. The extent to which these recent advances offer inferential improvements can be limited by the data requirements for quantifying individual‐level processes. This is especially true for SCR models that use non‐Euclidean distance to relax the restrictive assumption that individual space use is stationary and symmetrical to make inferences about landscape connectivity. To meet the challenges of scale and data quality, we propose integrating an explicit movement model with non‐Euclidean SCR for joint estimation of a shared cost parameter between individual and population processes. Here, we define a movement kernel for step selection that uses "ecological distance" instead of Euclidean distance to quantify availability for each movement step in terms of landscape cost. We compare performance of our integrated model to that of existing SCR models using realistic animal movement simulations and data collected on black bears. We demonstrate that an integrated approach offers improvements both in terms of bias and precision in estimating the shared cost parameter over models fit to spatial encounters alone. Simulations suggest these gains were only realized when step lengths were small relative to home range size, and estimates of density were insensitive to whether or not an integrated approach was used. By combining the fine spatiotemporal scale of individual movement processes with the estimation of population density in SCR, integrated approaches such as the one we develop here have the potential to unify the fields of movement, population, and landscape ecology and improve our understanding of landscape connectivity. [ABSTRACT FROM AUTHOR]

Long time series are important because they extend back to an era when animal populations were less influenced by habitat loss and climate change. Annual fluctuations in harvest yields are good proxies for large changes in population size and may reveal underlying ecological processes. From a variety of sources, we built a 142-year long time series representing the mean daily catch (CPUE) of willow ptarmigan Lagopus lagopus in southeastern Norway. CPUE decreased over the 142 years, from approximately 35 birds shot per day in early years to around two in the last years. There were three periods in the time series: a first period with 3-5 year cycles of high peaks and low troughs (1872-1900), a short second period with similarly high peaks, variable depth of troughs and variable cyclicity (1901-1916), and a third long period with much lower peaks and faded cycles (1917-2013). Yearly variation in CPUE was best explained by an interacting effect of small rodent peak years and period, with a reduced positive effect of rodents in the last period, and a positive effect of the North Atlantic Oscillation index in spring and early summer. None of the weather variables with significant time trends explained any variation in CPUE and we could therefore not attribute the decline in CPUE directly to climate change. We postulate that a long-term dampening of the amplitude in small rodent cycles combined with an increase in red fox numbers, have increased predation on alternative prey like ptarmigan, and prevented the populations from reaching their earlier peaks. Even though the present population of willow ptarmigan is only a fraction of what it was in former days, we recommend light hunting to motivate for monitoring and to keep public attention on the bird. [ABSTRACT FROM AUTHOR]

Camera or genetic data are increasingly used to estimate wildlife abundance and density. We integrated video camera data with genetic data over 7 years to estimate annual age‐structured apparent survival of American black bears (Ursus americanus). We identified 70 individuals through meticulous scrutiny of 7531 video captures, cross‐referenced with 721 genetic captures from hair samples concurrently collected from stations in view of cameras. We used the Cormack–Jolly–Seber model in Program Mark to estimate annual age‐structured apparent survival for yearling males, yearling females, 2+ year‐old males, and 2+ year‐old females. We manually calculated cub survival. We compared parameter estimates based on combined video and genetic data with those based on only genetic data. Combining video and genetic data provided a means to test video‐based identification accuracy, which was highest for females (97%–100%). Annual apparent survival was highest for yearling females (φ = 0.92, SE = 0.07), followed by 2+ year‐old females (φ = 0.88, SE = 0.05), 2+ year‐old males (φ = 0.84, SE = 0.06), and yearling males (φ = 0.80, SE = 0.14). Annual cub survival (φ = 0.86, SE = 0.07) was likely biased because we could not account for mortality that occurred in‐den through early spring. Annual apparent survival and recapture probabilities derived from only genetic data were lower than those derived from combined video and genetic data. Our finding that noninvasive data can be used to estimate annual age‐structured apparent survival of a species with relatively indistinct traits is broadly relevant to wildlife research and conservation. [ABSTRACT FROM AUTHOR]

Simple Summary: The Asian honeybee is an important pollinator in Asia that plays a vital role in maintaining biodiversity. Based on field surveys and personal observations, Asian honeybee populations in China were reported to be undergoing significant decline in 2005. However, a more recent survey revealed that its populations are stable and even slightly increased in some regions of China. Therefore, the status of declining Asian honeybee populations in China is still unclear. In this study, taking advantage of the abundant genomic data for Asian honeybees, we employed conservation genomics methods to understand the declining status of Asian honeybee populations in China and identify the causing factors. We found that most of the Asian honeybee populations of China showed a relatively stable population size during recent years, however, the population in Bomi, Tibet was in a serious decline and low temperatures and strong ultraviolet radiation should have synergistically led to this decline. Our study provides insights into the dynamic changes of Asian honeybee populations in China and identifies climate factors that underlie its population decline, which are valuable for the conservation of this important pollinator. The Asian honeybee, Apis cerana, is one of the most important native pollinators in Asia. Asian honeybees were believed to be under significant decline in China based on a report in 2005. On the contrary, a recent survey revealed that Asian honeybee populations in China are stable and even slightly increased in some regions. Therefore, the declining status of A. cerana populations in China is still unclear. Taking advantage of the abundant, publicly available genomic data for Asian honeybees in China, we employed conservation genomics methods to understand if Asian honeybee populations in China are declining and what the underlying climate factors are. We reconstructed the changes of effective population size (Ne) within the recent past for 6 population groups of Asian honeybees and found out that only one of them (population in Bomi, Tibet) showed a consistently declining Ne from the last 100 generations to 25 generations. Selective sweep analysis suggests that genes related to the tolerance of low temperatures and strong ultraviolet radiation are under selection in the declining population, indicating that these two climate factors most likely underlie the decline of BM populations during the recent past. Our study provides insights into the dynamic changes of Asian honeybee populations in China and identifies climate factors that underlie its population decline, which is valuable for the conservation of this important pollinator. [ABSTRACT FROM AUTHOR]

The winter diets of northern ungulates are sensitive to changes in environmental conditions and ungulate population densities. We hypothesized that the winter diets of smaller browser ungulates might not readily change in response to fluctuating environmental conditions. We analyzed long-term trends in the winter diet of the Japanese serow (Capricornis crispus) by analyzing rumen contents of 532 individuals over a span of 16 years among five populations along with changes in the population densities of sika deer (Cervus nippon) in Nagano Prefecture, central Japan. The winter diet composition of the serow was stable over the long term despite the increase in deer population density. The little-flexible nature of the serow diet may explain the long-term stability in the winter diets. [ABSTRACT FROM AUTHOR]

Noise remains an important challenge, particularly in informal settings where planning and regulation are relatively weak. This study aims at developing a model to predict noise in a largely informal urban Kano, the second most populated city in Nigeria. Sound level meter (SLM) 200 TL was used to measure noise at locations covering different land use: residential, industrial, commercial, educational, and administrative areas. Data were collected for seven days, and each day measurements were taken for six hours: 8–10 a.m., 12–2 p.m. and 4–6 p.m. Land use, population density, residential division, traffic volume, and land cover were used to generate a noise model using weighted geographic regression. The findings revealed that noise in the area is higher than the permissible limits set by the WHO and Nigeria's regulatory agency. The model identified population density as the most influencing factor, followed by land cover, traffic volume and distance to the road, then land use. Seventy three percent of the model's residual are below five, indicating a significant association between noise and the variables used. The R2 ranges between 18% and 26% depending on the time of the day. Noise in the area can be effectively control by paying serious attention to city planning and enforcing traffic regulation measures. [ABSTRACT FROM AUTHOR]

Population dynamics set the framework for human genetic and cultural evolution. For foragers, demographic and environmental changes correlate strongly, although the causal relations between different environmental variables and human responses through time and space likely varied. Building on the notion of limiting factors, namely that at any one time, the scarcest resource caps population size, we present a statistical approach to identify the dominant climatic constraints for hunter-gatherer population densities and then hindcast their changing dynamics in Europe for the period between 21,000 to 8000 years ago. Limiting factors shifted from temperature-related variables (effective temperature) during the Pleistocene to a regional mosaic of limiting factors in the Holocene dominated by temperature seasonality and annual precipitation. This spatiotemporal variation suggests that hunter-gatherers needed to overcome very different adaptive challenges in different parts of Europe and that these challenges varied over time. The signatures of these changing adaptations may be visible archaeologically. In addition, the spatial disaggregation of limiting factors from the Pleistocene to the Holocene coincided with and may partly explain the diversification of the cultural geography at this time. Here, the authors use climate and resource availability, to statistically model the limiting factors in the dynamics of hunter-gatherer population densities in Europe between 21,000 and 8,000 years ago. They find that limiting factors varied spatiotemporally and the effects of these may be visible in the archaeological record. [ABSTRACT FROM AUTHOR]