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Population characteristics of the Barbary sheep Ammotragus lervia, the only wild caprine in Northwest Africa, were investigated in a captive population located in a 150-ha fenced area within the Amassine reserve, Morocco, created for promoting wildlife watching tourism. We analysed the population trend during 20 years since the introduction of 10 individuals in 1999. Using direct counting in March-April 2016 to 2019, before herd dispersal, we assessed population size, age-sex structure, birth and survival rates. We estimated survival rates from mortality analysis using exponential regression models. The population size exhibited fluctuations over time expressed by significant exponential equations. We observed three successive phases corresponding each to a fast-growing period followed by a sharp decline. Estimated population density ranged from 0.25 to 0.41 ind. ha−1. Adult sex ratio varied from 67 to 91 rams per 100 ewes. Juveniles and subadults comprised 27–43 % of the population, and adults, rams and ewes, represented 26–31 % and, 29–45 %, respectively. Birth rate varied from 14 to 73 lambs per 100 ewes. The survival rate during the postnatal year approximated 35 %. For adult rams, it was around 69 % year−1. Our findings would be helpful for developing a sustainable population management plan, and assessing potential reintroduction/restocking in other areas. [ABSTRACT FROM AUTHOR]

Historical data on chinstrap penguin (Pygoscelis antarctica) breeding population sizes are sparse and sometimes highly uncertain, making it hard to estimate true population trajectories. Yet, information on population trends is desirable as changes in population size can help inform conservation assessments. Recently, Krüger (2023) (Diversity 2023, 15, 327) used chinstrap penguin nest count data to predict breeding colony size trends between 1960 and 2020, to estimate whether the level of population change within three generations exceeded IUCN Red List Criteria for "Vulnerable" populations. Chinstrap penguin population trends are an important research topic, but we caution that Krüger (2023)'s statistical analyses (intended to form the foundation for drawing valid, evidence-based inferences from sparse data) contain fundamental errors that invalidate that paper's findings. We discuss oversights in several key steps (data processing, exploratory data analysis, model fitting, model evaluation, and prediction) of that paper's analysis to help others detect and avoid some of the pitfalls associated with estimating population trends via mixed models. We also show through reanalysis that improved statistical modelling can yield better predictions of chinstrap penguin population trends, at least within the range of observed data. This case study highlights (1) the profound influence that seemingly minor differences in modelling procedures (both unintentional errors and other decisions) can have on predictions of population trends, and (2) the substantial inherent uncertainty in population trend predictions derived from sparse, heterogenous data. [ABSTRACT FROM AUTHOR]

Cliffs are marginal and poorly studied habitats that are home to a high proportion of endemic or threatened species. Here, we reviewed the survival patterns and population dynamics of plants growing on vertical cliffs and compared them to other plants with similar life forms that grow on the ground. To this end, we have compiled studies of cliff and ground-level plants from two main sources: MONITO and COMPADRE. The resulting dataset after applying some filters included a total of 243 populations of 134 plant species monitored for several years in the northern hemisphere. We tested whether survival rates of seedlings and older stages, population growth rates, and their temporal variability showed similar patterns between cliff and ground plants, and the relationship between those demographic parameters. Cliff plants showed higher survival rates for both seedlings and older life stages, as well as lower distance to population equilibrium and more stable population trends over time, compared to plants growing in the ground. Population equilibrium and temporal stability was highly correlated with the survival of post-seedling stages in both groups. These results suggest that cliff plants may be better adapted to withstand climatic variability than the more common ground-level plants occurring in less stressful environments. [ABSTRACT FROM AUTHOR]

A standardised monitoring is indispensable to identify trends of insect populations. However, until recently, a systematic monitoring of insects in Germany was missing. Therefore, the German federal ministry for the environment funded the conceptualisation of an insect monitoring scheme. Here, we inform about the general concept and structure of the German insect monitoring scheme (GIMS) and the steps taken and still to be taken for the implementation of the scheme. A first step was the development of the objectives, general concept und structure of the GIMS in close collaboration with the nature conservation authorities at the national and federal state levels, as the latter are responsible for the implementation of nature conservation-related monitoring schemes. The GIMS is structured into two sections: section 1 'Monitoring of common insects' and section 2 'Monitoring of rare insects'. Both sections contain modules that focus on selected aspects of insect diversity. In section 1, insect communities of the wider countryside will be monitored. Section 2 focuses on insect communities in rare habitats and species of high conservation value (e.g. threatened species). The next step was to develop standardised sampling methods for the modules in collaboration with experts and the nature conservation authorities. Wherever appropriate, synergies with other monitoring schemes were created, e.g. for combined analyses with environmental variables. Parallel to the development of the concept, several federal states have already implemented selected modules of the GIMS. Furthermore, the module 'Grasshoppers in grasslands' was tested during a pilot phase. By using the data from the pilot phase and the High Nature Value Farmland Monitoring scheme the relationship between high nature value farmland and grasshopper diversity was evaluated. This indicated the great potential of using synergies among monitoring schemes for joint data analyses and showed that it is worth exploring such approaches in greater depth. [ABSTRACT FROM AUTHOR]

Empirical data are essential to assess the outcomes of management decisions in the context of adaptive management. We used flyway‐level population indices of a declining game bird to assess population changes after introducing hunting management measures as part of the European Union (EU)‐wide Adaptive Harvest Management mechanism (AHMM). In one flyway, a full hunting ban led to the start of population recovery; numbers increased by 25% in 2 years and the 10‐year population trend improved from “moderate decline” to “stable.” In the other flyway, harvest was only reduced (allegedly by 60% although statistics from key countries were incomplete), and numbers continued to fall (−15% decline). Our study shows positive results of the leading AHMM for a landbird in Europe and provides empirical evidence of the speed of population response and the timeframe needed for change to occur and to be detected. It showcases the successful application of policy mechanisms underpinned by science. [ABSTRACT FROM AUTHOR]

Cliffs are marginal and poorly studied habitats that are home to a high proportion of endemic or threatened species. Here, we reviewed the survival patterns and population dynamics of plants growing on vertical cliffs and compared them to other plants with similar life forms that grow on the ground. To this end, we have compiled studies of cliff and ground-level plants from two main sources: MONITO and COMPADRE. The resulting dataset after applying some filters included a total of 243 populations of 134 plant species monitored for several years in the northern hemisphere. We tested whether survival rates of seedlings and older stages, population growth rates, and their temporal variability showed similar patterns between cliff and ground plants, and the relationship between those demographic parameters. Cliff plants showed higher survival rates for both seedlings and older life stages, as well as lower distance to population equilibrium and more stable population trends over time, compared to plants growing in the ground. Population equilibrium and temporal stability was highly correlated with the survival of post-seedling stages in both groups. These results suggest that cliff plants may be better adapted to withstand climatic variability than the more common ground-level plants occurring in less stressful environments.

A standardised monitoring is indispensable to identify trends of insect populations. However, until recently, a systematic monitoring of insects in Germany was missing. Therefore, the German federal ministry for the environment funded the conceptualisation of an insect monitoring scheme.Here, we inform about the general concept and structure of the German insect monitoring scheme (GIMS) and the steps taken and still to be taken for the implementation of the scheme. A first step was the development of the objectives, general concept und structure of the GIMS in close collaboration with the nature conservation authorities at the national and federal state levels, as the latter are responsible for the implementation of nature conservation-related monitoring schemes. The GIMS is structured into two sections: section 1 ‘Monitoring of common insects’ and section 2 ‘Monitoring of rare insects’. Both sections contain modules that focus on selected aspects of insect diversity. In section 1, insect communities of the wider countryside will be monitored. Section 2 focuses on insect communities in rare habitats and species of high conservation value (e.g. threatened species). The next step was to develop standardised sampling methods for the modules in collaboration with experts and the nature conservation authorities. Wherever appropriate, synergies with other monitoring schemes were created, e.g. for combined analyses with environmental variables.Parallel to the development of the concept, several federal states have already implemented selected modules of the GIMS. Furthermore, the module ‘Grasshoppers in grasslands’ was tested during a pilot phase. By using the data from the pilot phase and the High Nature Value Farmland Monitoring scheme the relationship between high nature value farmland and grasshopper diversity was evaluated. This indicated the great potential of using synergies among monitoring schemes for joint data analyses and showed that it is worth exploring such approaches in greater depth.

Monitoring population trends is pivotal to effective wildlife conservation and management. However, wildlife managers often face many challenges when analyzing time series of census data due to heterogeneities in sampling methodology, strategy, or frequency. We present a three‐step method for modeling trends from time series of count data obtained through multiple census methods (aerial or ground census and expert estimates). First, we design a heuristic for constructing credible intervals for all types of animal counts including those which come with no precision measure. Then, we define conversion factors for rendering aerial and ground counts comparable and provide values for broad classes of animals from an extant series of parallel aerial and ground censuses. Lastly, we construct a Bayesian model that takes the reconciled counts as input and estimates the relative growth rates between successive dates while accounting for their precisions. Importantly, we bound the rate of increase to account for the demographic potential of a species. We propose a flow chart for constructing credible intervals for various types of animal counts. We provide estimates of conversion factors for 5 broad classes of species. We describe the Bayesian model for calculating trends, annual rates of population increase, and the associated credible intervals. We develop a bespoke R CRAN package, popbayes, for implementing all the calculations that take the raw counts as input. It produces consistent and reliable estimates of population trends and annual rates of increase. Several examples from real populations of large African mammals illustrate the different features of our method. The approach is well‐suited for analyzing population trends for heterogeneous time series and allows a principled use of all the available historical census data. The method is general and flexible and applicable to various other animal species besides African large mammals. It can readily be adapted to test predictions of various hypotheses about drivers of rates of population increase. [ABSTRACT FROM AUTHOR]

In 1995, the first colony of Thalasseus sandvicensis settled in a saltmarsh islet in the Lagoon of Venice, NE Italy. The number of nesting pairs rose from 202 (1995) pairs to 3503 (2023), with the arrival of immigrants peaking in 2014 (+887 pairs) and 2023 (+1884). From 1995 to 2023, the number of breeding pairs showed a moderate increase (p

La actualización sobre la distribución y tamaño de poblaciones es fundamental para evaluar el estado de conservación de las especies, así como aplicar, en su caso, medidas de gestión orientadas a mantener o devolver a las mismas a un estado favorable. Con el objetivo de actualizar el conocimiento sobre el área de distribución, tamaño y parámetros reproductivos del buitre leonado Gyps fulvus en Gipuzkoa, en 2023 se volvió a realizar un censo en toda la provincia. Además, a partir de datos del censo de cabaña ganadera de Euskadi, se ha estimado la cantidad de carroña disponible en Gipuzkoa para determinar la capacidad de carga del medio y evaluar hasta qué punto esta disponibilidad juega un papel clave a la hora de explicar la evolución de la población en la provincia. El número de colonias en 2023 ascendió a 24, cuatro más que en 2018. Su distribución no cambia sustancialmente de la registrada durante los últimos años, concentrándose en los macizos más relevantes (Aizkorri, Aralar, Aiako Harria, Hernio-Altzolaras, montes orientales de Gipuzkoa y Jaizkibel). Se contabilizaron 407 parejas de adultos reproductores (ps), un 50,2% más que en 2018. El tamaño medio de parejas por colonia se sitúa en 16,6 ps (SE: 6,8 ps; rango: 2-70 ps). La mayor parte de las colonias (n = 13; 54,2%) acoge menos de 10 ps, mientras que por encima de 50 ps solo hay una colonia. La tendencia de la población a largo plazo (25 años) es de fuerte incremento, con una tasa de crecimiento medio anual de un 7,2% (SE: 0,4%). Se contabilizaron 333 pollos, de los que volaron 288 (86,5%). La productividad fue del 0,708 pollos/pareja constituida y el éxito reproductivo de 0,770 pollos/pareja que inicia la incubación. Partiendo de los datos del censo de 2020, la disponibilidad de ganado muerto en Gipuzkoa es de unos 1426870 kg/año, cifra teóricamente capaz de sustentar 3532 ps. Así, el estado de conservación de la especie en el territorio es, en la actualidad, favorable. Todo ello apunta a un escenario también favorable, al cual posiblemente contribuye la existencia de gran cantidad de biomasa en forma de carroña, suficiente para mantener no solo la actual población de buitres, sino su actual tasa de crecimiento. ABSTRACT: In order to assess the conservation status of the species and to apply management measures to maintain or return this to a favourable status, it is essential to gather the latest data on the distribution and size of populations. With the aim of updating information on the distribution area, size and reproductive parameters of the griffon vulture Gyps fulvus in Gipuzkoa, a census was conducted throughout the province in 2023. In addition, based on data from the Basque Country’s livestock census, the amount of carrion available in Gipuzkoa has been estimated in order to determine the carrying capacity of the territory and to assess to what extent this availability is relevant in explaining the evolution of this population. The number of colonies in 2023 rose to 24, four more than in 2018. Their geographic distribution remains similar from that recorded in recent years, being concentrated in the most relevant mountain ranges (Aizkorri, Aralar, Aiako Harria, Hernio-Altzolaras, eastern massifs of Gipuzkoa and Jaizkibel). Overall, 407 adult breeding pairs (ps.) were counted, 50.2% more than in 2018. The mean size of each colony is of 16.6 ps (SE: 6.8 ps; range: 2-70 ps). Most colonies (n = 13, 54.2%) host less than 10 ps, while there is only one with more than 50 ps. The long-term population trend (25 years) is markedly positive, with a mean annual growth rate of 7.2% (SE: 0.4%). Overall, 333 chicks were counted, from which 288 fledged (86.5%). The breeding parameters were: productivity, 0.708 chicks/formed pair; breeding success: 0.770 chicks/incubating pair. Based on the 2020 census data, the availability of dead livestock in Gipuzkoa is about 1,426,870 kg/year, which is theoretically sufficient to support 3,532 ps. Thus, the conservation status of the species in the territory is currently favourable. All of this points to a favourable scenario, where this large amount of carrion biomass is possibly sufficient to maintain not only the current griffon vulture population, but also its current positive growth rate.

This study describes the goat production system and breeding practices in selected districts of North Wollo zone, Ethiopia. Data were collected from 180 respondents through a semi-structured questionnaire and group discussions. Descriptive and GLM procedures were employed for data analysis. A mixed crop-livestock production system was the main production system in the area. The mean number of goats per household is 9.66 and they are mainly kept for cash income and meat consumption. The flock structure of indigenous goats consisted of a large number of female goats. Natural pasture and crop residue were the major feed resources in the dry and wet seasons, with an overall mean of 37.53% and 54.26%, respectively. Feed shortage, diseases, and drought were the major constraints for goat production. Most goat owners (97.1%) practiced an uncontrolled mating system. Most farmers (88.93%) reported selecting breeding goats to be a parent for the next generation. Body conformation and coat colour were the preferred traits for the selection of goats. The current level of goat management and breeding methods would not significantly enhance goats’ productivity and profitability. Therefore, designing management and genetic improvement programmes would be vital to improving the productivity of indigenous goats.

Hong Kong is one of the busiest metropolises, and the Eurasian otter Lutra lutra is one of its most threatened species. We collected published data for 1890–2020 to document changes in local otter abundance and distribution over time. The 108 records revealed new distribution data and showed that decline began as early as the 1930s. The local Eurasian otter is strongly associated with coastal and alluvial wetlands, and its last refugium, the Yuen Long floodplain draining the Mai Po Inner Deep Bay Ramsar Site, has always been a critical habitat. Our analysis suggests that hunting is unlikely to be a major cause of the otter's decline. Rather, dependence on lowland wetlands makes it particularly susceptible to habitat loss caused by increasing urbanization. Auxiliary infrastructures and water pollution have also exacerbated wetland degradation to the detriment of otters and their prey. There is a need for greater cooperation amongst government agencies and landowners to guarantee otter survival: priority steps include the establishment of additional and interconnected wetland reserves, better stakeholder engagement and enforcement efficiency to tackle entrenched pollution problems, and flood prevention schemes that preserve or restore functional riverine ecosystems within critical otter habitats. The current otter distribution range has been earmarked for development in a government-led mega urbanization plan; the plight of the local Eurasian otter needs to be widely publicized to garner stakeholders' support and galvanize immediate conservation actions across society.

Many threatened species require ongoing management, which is often funded through short project cycles. Evaluating whether the management is effective in protecting a species is important to inform future management investments. For migratory species, management may affect only part of a species' annual cycle, and reversing a population decline is challenging to achieve and demonstrate. Here, we evaluate whether conservation management projects funded by the European LIFE programme to safeguard a migratory vulture population achieved their major objective of stabilizing the target breeding population. Between 2012 and 2022, an international alliance of conservation organizations implemented multiple actions to reduce poisoning, direct persecution, and electrocution and collision with power lines along the Eastern Mediterranean flyway. We monitored breeding territories of the Balkan population of the globally endangered Egyptian Vulture Neophron percnopterus between 2006 and 2022, and tracked 60 young birds with GPS transmitters since 2010. We used these data to examine whether population growth rate and survival probability had increased since project implementation. The mean annual survival probability of adult territorial birds increased by 1.9% since 2014 from 0.937 to 0.955, and the monthly survival probability of wild juvenile birds increased by 9.7% from 0.833 to 0.914 since 2018. The population growth rate across the Balkans increased by 6.9% from 0.939 before 2018 to 1.005 since 2018. This indicates that the Egyptian Vulture population has remained stable for the past 5 years (2018–2022), but at a population size that is only half (105 adult territorial birds in 2022) than at the beginning of the time series (204 in 2006). We caution that ongoing management along the flyway and reinforcement are required to ensure that the Egyptian Vulture population on the Balkans can recover, but we show that flyway‐scale collaboration of direct conservation actions can have lasting benefits for migratory species. [ABSTRACT FROM AUTHOR]

Little Owl (Athene noctua Scop., 1769) is common and widespread throughout Bulgaria, inhabiting various habitats, including farmland, orchards, villages, and urban areas. In recent years, its population has declined in almost all of Europe. The present study revealed an average Little Owl population density of about 0.05 breeding pairs / km² in Bulgaria. Its density varies depending on the region. The species is more abundant in the lowlands of northern Bulgaria, where the density can reach up to 0.07 breeding pairs / km², while in the mountains, the density is lower, with only 0.03 breeding pairs / km² in some areas. The Little Owl population in Bulgaria declined between 2007 and 2016 by 30 %. The main factor in Bulgaria for the decrease in numbers is the construction of new buildings or the renovation of old ones. Among the factors negatively influencing the species' population are habitat loss and fragmentation, changes in agricultural practices, and changes in prey availability. The places where they nest or roost depend on human presence. In particular, converting traditional farmland to intensive monoculture has been identified as a potential threat to the Little Owl population in some regions of Bulgaria. [ABSTRACT FROM AUTHOR]

Hong Kong is one of the busiest metropolises, and the Eurasian otter Lutra lutra is one of its most threatened species. We collected published data for 1890–2020 to document changes in local otter abundance and distribution over time. The 108 records revealed new distribution data and showed that decline began as early as the 1930s. The local Eurasian otter is strongly associated with coastal and alluvial wetlands, and its last refugium, the Yuen Long floodplain draining the Mai Po Inner Deep Bay Ramsar Site, has always been a critical habitat. Our analysis suggests that hunting is unlikely to be a major cause of the otter's decline. Rather, dependence on lowland wetlands makes it particularly susceptible to habitat loss caused by increasing urbanization. Auxiliary infrastructures and water pollution have also exacerbated wetland degradation to the detriment of otters and their prey. There is a need for greater cooperation amongst government agencies and landowners to guarantee otter survival: priority steps include the establishment of additional and interconnected wetland reserves, better stakeholder engagement and enforcement efficiency to tackle entrenched pollution problems, and flood prevention schemes that preserve or restore functional riverine ecosystems within critical otter habitats. The current otter distribution range has been earmarked for development in a government-led mega urbanization plan; the plight of the local Eurasian otter needs to be widely publicized to garner stakeholders' support and galvanize immediate conservation actions across society. [ABSTRACT FROM AUTHOR]

Estimating population trends provides valuable information for conservation biologists. Although there are many methods for estimating demographic rates, capture-mark-recapture (CMR) methods are known to be the most realistic method that can provide detailed data on individuals and populations, including the achievement of conservation goals. This study focused on determining the population trend of Pelophylax bedriagae caralitanus, Beyşehir frog using the CMR method in a protected area during the 2011-2019 breeding seasons. Our CMR data led to the selection of model-considering constant survival rates, capture/recapture probabilities, and year-specific immigration/emigration patterns [Φ(··) y'(t) y"(t) p(··) = c(··) N(t)]-as the most fitting biological hypothesis among 22 constructed models. According to the best-fitted model, 6% of all individuals in Gölcük population can be captured during each sampling occasion. The annual survival rates show low variation between years, and the mean survival rate was estimated as 0.85, that means 85% of the individuals of Pelophylax bedriagae caralitanus in the Gölcük population were able to live on to subsequent breeding seasons. The average population size of Gölcük population for nine consecutive years was estimated as 5094 (range 4834-5382) individuals that shows minor and acceptable levels of population size fluctuations, and slightly increasing over the years. These findings can guide future research, aiding in assessing population size changes in both protected and nonprotected areas while understanding population decline trends. [ABSTRACT FROM AUTHOR]

Local biodiversity monitoring is important to assess the effects of global change, but also to evaluate the performance of landscape and wildlife protection, since large-scale assessments may buffer local fluctuations, rare species tend to be underrepresented, and management actions are usually implemented on local scales. We estimated population trends of 58 bird species using open-population N-mixture models based on count data in two localities in southeastern Spain, which have been collected according to a citizen science monitoring program (SACRE, Monitoring Common Breeding Birds in Spain) over 21 and 15 years, respectively. We performed different abundance models for each species and study area, accounting for imperfect detection of individuals in replicated counts. After selecting the best models for each species and study area, empirical Bayes methods were used for estimating abundances, which allowed us to calculate population growth rates (λ) and finally population trends. We also compared the two local population trends and related them with national and European trends, and species functional traits (phenological status, dietary, and habitat specialization characteristics). Our results showed increasing trends for most species, but a weak correlation between populations of the same species from both study areas. In general, local population trends were consistent with the trends observed at national and continental scales, although contrasting patterns exist for several species, mainly with increasing local trends and decreasing Spanish and European trends. Moreover, we found no evidence of a relationship between population trends and species traits. We conclude that using open-population N-mixture models is an appropriate method to estimate population trends, and that citizen science-based monitoring schemes can be a source of data for such analyses. This modeling approach can help managers to assess the effectiveness of their actions at the local level in the context of global change. [ABSTRACT FROM AUTHOR]

The increased pressures generated by human activities in form of climate change and habitat fragmentation have caused serious threats for Sindh ibex (Capra aegagrus blythii). Balochistan, recognized as one of the most vulnerable regions to climate change in Pakistan, has limited data on the distribution and population status of this species. To address this gap, our study aims to assess the spatial and temporal distribution and population trend of Sindh ibex in the Khuzdar and Lasbela districts of Balochistan. The study covered an area of approximately 45,123.97 km2. It involved a double-observer survey at ten sites from 2019 to 2022, using the BBRecapture package in the R programming language to estimate ibex population trend and dispersion. We provided a comprehensive update of the species geographic range, along with estimates of its current abundance and population trends. Over the course of four years, the ibex population fluctuated. The ibexes detected dropped from 720 (male to female ratio 1:1.21) and 710 (male to female ratio 1:1.08) in 2019 and 2020, respectively, to 550 (male to female ratio 1:1.35) and 548 (male to female ratio 1:1.09). Overall, this study provides valuable insights into the population trends, gender ratios, habitat preferences, and density of Sindh ibex in Balochistan over the four-year period. These findings contribute significantly to the baseline data on the species ecology and will further help in the conservation of these species at local scale. [ABSTRACT FROM AUTHOR]

Abstract Monitoring population trends is pivotal to effective wildlife conservation and management. However, wildlife managers often face many challenges when analyzing time series of census data due to heterogeneities in sampling methodology, strategy, or frequency. We present a three‐step method for modeling trends from time series of count data obtained through multiple census methods (aerial or ground census and expert estimates). First, we design a heuristic for constructing credible intervals for all types of animal counts including those which come with no precision measure. Then, we define conversion factors for rendering aerial and ground counts comparable and provide values for broad classes of animals from an extant series of parallel aerial and ground censuses. Lastly, we construct a Bayesian model that takes the reconciled counts as input and estimates the relative growth rates between successive dates while accounting for their precisions. Importantly, we bound the rate of increase to account for the demographic potential of a species. We propose a flow chart for constructing credible intervals for various types of animal counts. We provide estimates of conversion factors for 5 broad classes of species. We describe the Bayesian model for calculating trends, annual rates of population increase, and the associated credible intervals. We develop a bespoke R CRAN package, popbayes, for implementing all the calculations that take the raw counts as input. It produces consistent and reliable estimates of population trends and annual rates of increase. Several examples from real populations of large African mammals illustrate the different features of our method. The approach is well‐suited for analyzing population trends for heterogeneous time series and allows a principled use of all the available historical census data. The method is general and flexible and applicable to various other animal species besides African large mammals. It can readily be adapted to test predictions of various hypotheses about drivers of rates of population increase.

Greece holds the third larger breeding population of Dalmatian Pelican in the world. We present data about the establishment and growth, breeding performance and conservation status for all six colonies of the species in Greece for 40 years. Main features of wetlands and colonies are described. We discuss the local, regional and global natural and anthropogenic factors that may have affected colony growth. After 1982 colony surveys were carried out with various methods, adapted to the particularities of each wetland and availability of resources, and targeted estimating number of nests and number of near-fledged young via direct counting either during on-site visits or from vantage points, and recently, counts on photos taken by drones flown one or more times during breeding. Number of nests in Lake Mikri Prespa rose from ca. 100 to 1200-1500 and levelled-off. DPs from Prespa started breeding successfully in Kerkini in 2004 after placement of artificial nesting rafts. The Karla Reservoir was colonised in 2011, just two years after it started filling with water. The DP colony on Lake Chimaditis, an important stop over and feeding site, probably initiated around 2016 and continues growing. The two colonies at the western coastline have limited exchanges with those in the eastern part of the country. Amvrakikos increased and levelled off recently as conservation and management measures restricted disturbance, whilst emigrants re-established the old colony at Messolonghi in 2011 which continues to grow. The overall breeding population in Greece grew from ca 100 to over 2000 br pairs showing an annual growth rate of 7.9%. Younger colonies show high annual growth rates clearly attributed to immigration, while older colonies have growth rates less than 10%. Interacting natural and anthropogenic factors are assumed to have contributed to pelican increase in Greece the last 40 years: better legal protection status, increasingly effective protection, patrolling and conservation measures; public awareness campaigns; provision of artificial nesting structures; increased winter survival due to higher temperatures owed to climate change; less disturbance and persecution due to decline of fisheries; increasing abundance and availability of fish due to eutrophication and climate change; increasing numbers of sympatric great cormorants rendering pelican fishing more efficient; appearance of new wetlands and change of wetlands due to human intervention works.

Abstract For rewilding the depleted crocodylian populations in India, a targeted ‘one-species one area’ based conservation approach was adopted in the early-1970s. Suitable habitats were identified and designated as protected areas, specifically targeted to recover a particular crocodylian species. A ~ 610 km stretch of Chambal River in the Ganga River Basin was declared as National Chambal Sanctuary to restore the ‘Critically Endangered’ gharial (Gavialis gangeticus), where active management of mugger (Crocodylus palustris) was discouraged. In the present study, we examined the population trends, occupancy, and genetic status of mugger by conducting population monitoring and genetic assessment to understand the status of potentially competitive mugger in the Sanctuary. Our finding suggests that the mugger population has notably increased and colonised the Sanctuary. We observed a moderate level of genetic diversity in the mugger, which was relatively higher compared to the gharial in the Sanctuary. The rapid colonization of ecological generalist mugger raises concerns about potential competition with ecological specialist gharial threatening its long-term sustainability. Considering the coexistence dynamics between the species, it is essential to extend adaptive management strategies for mugger to ensure successful recovery of gharial population in the Sanctuary.

Population size and geographical range are the key quantitative criteria used by the IUCN to assess the conservation status of a species. However, such information is often incomplete and inconsistent, even for seemingly abundant species. To assess the population and conservation status of Indian primates, we conducted a systematic review of recent research using the searching, appraisal, synthesis and analysis (SALSA) approach. We reviewed a total of 41 studies on Indian primates conducted during the last 2 decades (2000–2021) for information on various parameters that influence their conservation. We found that 20 out of a total of 26 primate species were evaluated for their population status, and the majority of these studies (71%) showed an overall declining population trend. Remarkably, all but one of the studies conducted exclusively within protected areas revealed declining population trends, whereas trends were more variable for primate populations in non-protected areas. Our data indicate that only 27% (n = 7) of Indian primate species have been surveyed or re-surveyed to assess their population status within the last 5 years. Although threats vary in time and space from species to species, 78% of the studies recorded natural system modifications including habitat loss and fragmentation among the main threats to the survival of Indian primates. Most studies on the population status of Indian primates have either been spatially limited or used outdated methods. We recommend that future studies adopt robust techniques to estimate populations and work across larger geographical scales to develop effective management strategies for the conservation of primates in India.

Historical data on chinstrap penguin (Pygoscelis antarctica) breeding population sizes are sparse and sometimes highly uncertain, making it hard to estimate true population trajectories. Yet, information on population trends is desirable as changes in population size can help inform conservation assessments. Recently, Krüger (2023) (Diversity 2023, 15, 327) used chinstrap penguin nest count data to predict breeding colony size trends between 1960 and 2020, to estimate whether the level of population change within three generations exceeded IUCN Red List Criteria for “Vulnerable” populations. Chinstrap penguin population trends are an important research topic, but we caution that Krüger (2023)’s statistical analyses (intended to form the foundation for drawing valid, evidence-based inferences from sparse data) contain fundamental errors that invalidate that paper’s findings. We discuss oversights in several key steps (data processing, exploratory data analysis, model fitting, model evaluation, and prediction) of that paper’s analysis to help others detect and avoid some of the pitfalls associated with estimating population trends via mixed models. We also show through reanalysis that improved statistical modelling can yield better predictions of chinstrap penguin population trends, at least within the range of observed data. This case study highlights (1) the profound influence that seemingly minor differences in modelling procedures (both unintentional errors and other decisions) can have on predictions of population trends, and (2) the substantial inherent uncertainty in population trend predictions derived from sparse, heterogenous data.

Population size and geographical range are the key quantitative criteria used by the IUCN to assess the conservation status of a species. However, such information is often incomplete and inconsistent, even for seemingly abundant species. To assess the population and conservation status of Indian primates, we conducted a systematic review of recent research using the searching, appraisal, synthesis and analysis (SALSA) approach. We reviewed a total of 41 studies on Indian primates conducted during the last 2 decades (2000–2021) for information on various parameters that influence their conservation. We found that 20 out of a total of 26 primate species were evaluated for their population status, and the majority of these studies (71%) showed an overall declining population trend. Remarkably, all but one of the studies conducted exclusively within protected areas revealed declining population trends, whereas trends were more variable for primate populations in non-protected areas. Our data indicate that only 27% (n = 7) of Indian primate species have been surveyed or re-surveyed to assess their population status within the last 5 years. Although threats vary in time and space from species to species, 78% of the studies recorded natural system modifications including habitat loss and fragmentation among the main threats to the survival of Indian primates. Most studies on the population status of Indian primates have either been spatially limited or used outdated methods. We recommend that future studies adopt robust techniques to estimate populations and work across larger geographical scales to develop effective management strategies for the conservation of primates in India. [ABSTRACT FROM AUTHOR]

The practice of space-for-time substitution assumes that the responses of species or communities to land-use change over space represents how they will respond to that same change over time. Space-for-time substitution is commonly used in both ecology and conservation, but whether the assumption produces reliable insights remains inconclusive. Here, we tested space-for-time substitution using data from the North American Breeding Bird Survey (BBS) and Global Forest Change (GFC) to compare the effects of landscape-scale forest cover on bird richness and abundance over time and space, for 25 space-time comparisons. Each comparison consisted of a landscape that experienced at least 20% forest loss over 19 years (temporal site) and a set of 15-19 landscapes (spatial sites) that represented the same forest cover gradient over space in 2019 as experienced over time in their corresponding temporal site. Across the 25 comparisons, the observed responses of forest and open-habitat birds to forest cover over time generally aligned with their responses to forest cover over space, but with comparatively higher variability in the magnitude and direction of effect across the 25 temporal slopes than across the 25 spatial slopes. On average, the mean differences between the spatial and temporal slopes across the 25 space-time comparisons frequently overlapped with zero, suggesting that the spatial slopes are generally informative of the temporal slopes. However, we observed high variability around these mean differences, indicating that a single spatial slope is not strongly predictive of its corresponding temporal slope. We suggest that our results may be explained by annual variability in other relevant environmental factors that combine to produce complex effects on population abundances over time that are not easily captured by snapshots in space. While not being a 1:1 proxy, measuring bird responses to changes in habitat amount in space provides an idea on how birds might be expected to eventually equilibrate to similar changes in habitat amount over time. Further, analyses such as this could be potentially used to screen for cases of regional space-time mismatches where population-limiting factors other than habitat could be playing a more important role in the population trends observed there. [ABSTRACT FROM AUTHOR]

This study presents insights from a comprehensive analysis of bird counts conducted at Narathali waterbody in Buxa Tiger Reserve between 2009 and 2019. Thirteen bird species were monitored, including six wintering duck species and seven resident waterfowl species. The population trends of these birds remained relatively constant throughout the study period. Additionally, the study documented raptor counts and compiled a checklist of waterbirds observed at the waterbody. These findings enhance our understanding of bird population dynamics in this significant habitat and provide valuable information for the conservation and management of the Buxa Tiger Reserve. [ABSTRACT FROM AUTHOR]

Threatened species receive much attention in conservation science and practice. Species currently declining, but not yet listed as threatened, also deserve consideration to reduce their risk of sliding towards extinction and to maintain their functional roles in ecosystems. Information on declining bird species in Australia is available from four main sources: national databases, syntheses of historical change, regional monitoring programmes and summaries for guilds of species. Many species show evidence of decline; declines of species are occurring nation-wide, and they are ongoing. Trends for individual species vary geographically; they may be declining in part of their range but stable elsewhere. Common trajectories of population decline include: (a) a downward linear trend; (b) a marked downturn, sustained at a lower level; and (c) fluctuations through time associated with episodic events (e.g. drought) and incomplete recovery. Ongoing declines affect ecosystems through reduced species richness, homogenisation of bird communities, changes to interspecific interactions and ecosystem services, and contributing to extinction debt. Improving the conservation outlook for declining species requires systematic monitoring to know where, when and how much decline is occurring, together with protection of critical habitats and source populations, ambitious programmes of restoration, and identification and effective control of threats. Responding to declining species offers opportunities for community engagement, monitoring and action at a local and regional level. New ways are needed to incorporate such species in conservation planning and environmental regulation at a regional scale, to give them greater visibility and avoid local declines accumulating until taxa become nationally threatened. Many bird species in Australia, not (yet) listed as threatened, are experiencing population decline and warrant greater attention in conservation planning and management. Patterns of change for individual species vary regionally, depending on past land-use and current pressures. Ongoing decline and loss of species has profound consequences for Australian ecosystems, including depleted and homogenised bird communities and reductions in the diverse ecosystem services that birds provide. New approaches are needed to provide formal recognition and appropriate management for declining species, particularly at a regional level, so they become more visible in environmental planning and can persist in regional landscapes. [ABSTRACT FROM AUTHOR]

Although the associations between climate, food conditions and reproduction in the wild has been the focus of numerous studies in recent years, we still know little about population level responses to climate and fluctuating food conditions in long-lived species and during longer periods of time. Here, we assessed the relative importance of the abundance of the main prey in winter (small mammals), and winter climate on population size and productivity in a Tawny Owl (Strix aluco) population in southern Finland during a 40-year period. We studied how population trends changed over time and in relation to winter weather and small mammal abundance on three levels: total estimated population size, proportion of breeders and population productivity. We identified declining trends in each population parameter over time, as well as directional changes in climate variables and prey abundance. Overall, small mammal abundance was the foremost predictor in explaining the variation in the number of active territorial pairs (population size). Moreover, both prey abundance and winter temperature significantly affected the proportion of territorial pairs that attempted to breed and thereby total offspring production, which reveals the relevance of winter weather conditions for population productivity. These results provide additional support to the view that changes in climate can modify predator–prey interactions leading to functional changes in the food web. [ABSTRACT FROM AUTHOR]

House crow is important concerning economy, ecology and culture. Reports are available regarding decline in house crow population. In contrast to this some countries are running eradication programs against this creature. In these circumstances it is logical to find population trend of house crow. We recorded the spatio-temporal variation in house crow population at certain part of the city Prayagraj (U.P.), India. The total numbers of crow were enumerated through direct roost count method at 12 different roosting sites visited fortnightly. Student t-test and one way ANOVA were performed and data were represented with graphs using MS excel (version 2007). Hike in house crow population in consecutive years 2020 (2385.66±323.73), 2021 (2586.16±321.73) and 2022 (2792.00±337.69) was significant (p<0.0001). Population was at its peak during October to February, while lowest in June and July. Annual average population at each roost sites was also fluctuating. The mean population of house crow was significantly lower in the breeding season (2333.70±275.88) than in non-breeding season (2841.97±102.59)(p<0.0001). Differences in mean population during summer (2386.20±335.19), monsoon (2450.83±280.02) and winter (2855.95±104.94) were significant for all comparisons (p<0.001). Thus, the population of house crow was shown to rising for last few years at least in studied area. Easily available human refuses/garbage, dead carcasses, highly opportunistic feeding and breeding habit may be reason for increasing trend in house crow population. [ABSTRACT FROM AUTHOR]

Black kite (Milvus migrans) is an important bird playing significant role in environment sustainability, economy, and culture. Its current population status is of concern in rapidly changing urban scenario. The studied area was spread over approximately 20 Km2at outskirt of the city Prayagraj (U.P.), India. Observed area had humid subtropical climate typical to north-central India. There is easy availability of food items, water and shelter for this bird to reside and propagate. Point count method was applied to count Black kite at 7 most probable sites of its finding. Each site was observed in the evening twice in a month during maximum activity of the black kite. Data were represented and analysed with the help of suitable graphical mean and statistical tests. The mean population increased in subsequent years during study period. We recorded mean population 79.42±22.98 in year 2020. It increased to 109.67±39.92 in year 2021 and 143.58±51.75 in year 2022. Increase in mean population was significant while comparing population of year 2020 and 2022. Mean population of Black kite was found to oscillate every month. It was highest in the month of September (169.00±54.51) and lowest in the month of May (56.67±17.01). Yearly fluctuation in mean population was also noticed at each count points. Mean population was highest during monsoon season (137.60±40.41) and lowest in summer (72.33±17.63) with insignificant difference (p>0.05). Insignificant difference (p>0.05) in mean population was noticed during breeding (118.19±41.96) and non-breeding (100.66±53.19) season. Food availability and breeding grounds are important in population distribution. Dispersal and local migration play important role in population regulation. This study clearly shows how urbanization is favouring some opportunistic birds to survive. [ABSTRACT FROM AUTHOR]

Based on regular surveys of the distribution of rookeries and the number of nesting birds of Corvus frugilegus Linnaeus, 1758 carried out in 2002–2020 using the TRIM (TRends & Indices for Monitoring data), the trajectory of change in the rook population has been estimated. The total size of the breeding population of rooks in Kharkiv City has decreased by 95.4 % over the last 80 years, from 940 to 43 breeding pairs. The general trend for 1939–2020 is a moderate decline (multiplicative slope 0.980, standard error 0.004; p < 0.01). A similar trend was observed for 2002–2020 when surveys were regular, i. e. a moderate decline (multiplicative slope 0.920, standard error 0.021; p < 0.01). Rooks still use the centre of the city for nesting, as they did in the early 1940s, but from the 1980s they began to breed in the eastern part of Kharkiv, where most of the population is now concentrated. Rooks breed in two clustered colonies, one in the central and one in the eastern part of Kharkiv City, about 13 km apart. The colonies are not numerous (all less than 50 pairs) in the last 10 years. The possible causes of the decline of the rook population in Kharkiv City are discussed. [ABSTRACT FROM AUTHOR]

Indigenous sheep breeds in South Africa play an important role in local food security and they are adapted to local conditions. Their genetic and cultural values have to be recognised for national importance. The conservation of these breeds is very critical as most of them are already classified as endangered. The South African government has the initiative to attempt the conservation of these animals; however, it comes with several challenges. In addition to funding, breed conservation demands farmers to understand and recognise the role of such breeds in society. This is especially crucial in the rural communal lands where breeds are kept. Farmers that raise indigenous breeds should be taught the necessity of maintaining the purity of these breeds. Indigenous sheep breeds in South Africa are not favored by the commercial farmers and thus they are more vulnerable. This review outlines the nature of sheep farming and the conservation status of four indigenous sheep breeds in South Africa. The effort and challenges that are met in current conservation arrangements are discussed. Moreover, we emphasise on the conservation techniques that are employed in South Africa. [ABSTRACT FROM AUTHOR]

Knowledge about the conservation status of a species is crucial for its protection in the long run. It provides insights into the geographic range, population size and trend, which are useful in management activities towards safeguarding the future of a species. The idle crayfish, Austropotamobius bihariensis, is a recently described crayfish species that has not yet undergone a full conservation assessment. Here, we present our extensive 13-year study that aimed to fill this gap by investigating and monitoring the species' entire geographic occurrence range and quantifying its subpopulations. Although it is an endemic crayfish located in the Apuseni Mountains (Romania), its range and population is stable. The observed relative abundance is highly unbalanced within subpopulations, with 71% falling below ten individuals per 100 m river stretch. We documented four extinct subpopulations (ca. 16%), whereas more than half of the subpopulations being in a size-decreasing trend. Since no invasive crayfish were detected in (or very close to) its distribution area, the idle crayfish can still be considered safe against invasions. However, based on our findings and following the IUCN Red List Guidelines, we concluded that idle crayfish's most appropriate conservation status is Endangered. IUCN ratification is required for increased significance.

Among the largest fish species, the basking shark (Cetorhinus maximus) is found circumglobally in temperate and tropical waters. Though historical documents have recorded their presence in the California Current Ecosystem (CCE), basking sharks are now only rarely observed in this part of their range. We compiled recent and historical data from systematic surveys (1962–1997) and other sources (1973–2018) to (i) examine temporal patterns of basking shark sightings in the CCE, and (ii) determine the spatial, temporal, and environmental drivers that have affected basking shark presence and distribution here for the last 50 years. We first calculated variation in basking shark sightings and school size over time. We then generated species distribution models using the systematic survey data and evaluated the performance of these models against the more recent non-systematic sightings data. The sightings records indicated that the number of shark sightings was variable across years, but the number and probability of sightings declined in the mid-1980s. The systematic survey data showed up to nearly 4,000 sharks sighted per year until the 1990s, after which there were no sightings reported. In parallel, there was more than a 50% decline in school size from the 1960s to the 1980s (57.2 to 24.0 individuals per group). During the subsequent decades in the non-systematic data (>1990), less than 60 sharks were sighted per year. There were no schools larger than 10 reported, and the mean school size in the last decade (2010s) was 3.53 individuals per group. Low sea surface temperature and high chlorophyll a concentration increased sightings probability, and prevailing climatic oscillations (El Nino-Southern Oscillation index, North Pacific Gyre Oscillation, Pacific Decadal Oscillation) were also correlated with basking shark presence. Lastly, we observed a significant shift in the seasonality of sightings, from the fall and spring during the systematic survey period to the summer months after the 2000s. We conclude by offering suggestions for future research and conservation efforts; specifically, coordinating the documentation of fisheries mortalities and sightings throughout the Pacific basin would facilitate more robust population estimates and identify sources of mortality. Additionally, monitoring shark fin markets and developing region-specific genetic markers would help ensure that convention on international trade in endangered species (CITES) regulations are being followed.

The Tarim red deer Cervus hanglu has been recently recognized as a separate deer species with populations in China, Central Asia and Kashmir. These populations are few, isolated and at risk of extinction. The documented range of the Kashmir population of the hangul, now recognized as Cervus hanglu hanglu, is restricted to c. 808 km2 and comprises < 200 individuals, confined mainly to the 141 km2 Dachigam National Park. A few relict herds inhabit the surrounding landscape. Here we analyse the results of almost 20 years of population monitoring (January 2001–March 2020). We found that this population is unable to increase despite full protection within Dachigam National Park. We performed a population viability analysis using both deterministic and stochastic simulations and found that further population decrease is likely. We recommend the use of improved monitoring methods to investigate the population dynamics of the hangul and the implementation of measures to reduce the risk of extinction faced by this small population. Science-based conservation policies, including ex situ conservation and reintroduction programmes, will be required to increase the hangul population size and range.

Based on regular surveys of the distribution of rookeries and the number of nesting birds of Corvus frugilegus Linnaeus, 1758 carried out in 2002–2020 using the TRIM (TRends & Indices for Monitoring data), the trajectory of change in the rook population has been estimated. The total size of the breeding population of rooks in Kharkiv City has decreased by 95.4 % over the last 80 years, from 940 to 43 breeding pairs. The general trend for 1939–2020 is a moderate decline (multiplicative slope 0.980, standard error 0.004; p < 0.01). A similar trend was observed for 2002–2020 when surveys were regular, i. e. a moderate decline (multiplicative slope 0.920, standard error 0.021; p < 0.01). Rooks still use the centre of the city for nesting, as they did in the early 1940s, but from the 1980s they began to breed in the eastern part of Kharkiv, where most of the population is now concentrated. Rooks breed in two clustered colonies, one in the central and one in the eastern part of Kharkiv City, about 13 km apart. The colonies are not numerous (all less than 50 pairs) in the last 10 years. The possible causes of the decline of the rook population in Kharkiv City are discussed.

Black-faced Spoonbills (Platalea minor) are listed as Endangered. More than 50% of these spoonbills winter regularly on the southwest coast of Taiwan. We used long-term population trend models to analyze 3 different datasets: (1) a biweekly census of 16 sampling sites in 3 habitat regions in southwest Taiwan 2007–2022, (2) a country-wide census of spoonbills 1991–2022, and (3) a worldwide census 2003–2022. From the biweekly monitoring data from southwest Taiwan, we found divergent spoonbill population trends and rates of habitat use in the 3 different habitat regions surveyed: a 2.8% per year increase in the number of birds wintering in the newly established Budai-Beimen Wetlands, a 2.6% per year decrease in the Cigu Salt Pan-Zengwun Estuary population, and a stable population in Sihcao-Yongan Wetlands. The result of biweekly monitoring data and the population time series analysis showed that in the late wintering period of each year, the combined habitat use rate was only 75.1% of the previous year's, a rate driven down by the Cigu Salt Pan-Zengwun Estuary population whose habitat use rate is only 59.0%. From the 1991–2022 Taiwan country-wide and global datasets, we found a linear trend showing the Black-billed Spoonbill population has increased at a rate of 10.4% and 10.3% per year, respectively. During the most recent 15 years, the population growth rate of this bird has significantly slowed down worldwide, with a rate of increase of 8.4% per year. We consider that maintaining the biodiversity of salt pan wetlands for protecting Black-faced Spoonbills is pivotal. 저어새(Platalea minor)는 멸종위기종으로 등록되어 있습니다. 저어새의 50% 이상이 대만 남서부 해안에서 정기적으로 겨울을 보냅니다. 우리는 장기 인구 추세 모델을 사용하여 3가지 다른 데이터 세트를 분석했습니다. (1) 2007년부터 2022년까지 대만 남서부 해안의 3개 서식지 지역에서 16개 샘플링 지점에서 얻은 2주간의 조사 데이터. (2) 1991년부터 2022년까지 대만 전역의 저어새 조사 데이터. (3)2003년부터 2022년까지의 전 세계 왕눈이 조사 데이터를 포함한 3가지 데이터 세트를 분석했다. 대만 남서부의 격주 모니터링 데이터에서 우리는 신규 설치된 부다이-베이먼 습지에서 에서 겨울을 보내는 새들의 수는 연간2.8% 증가하고 시구 소금 판젠원 하구 인구는 연간 -2.6% 감소하고, 시카오-용안 습지의 안정적인 개체 수. 격주 모니터링 데이터와 인구 시계열 분석 결 매년 겨울철 후반에 총 서식지 사용률은 전년도의 75.1%에 불했으며, 이 비율은 서식지 사용률이 59.0%에불한 시구 소금 판젠원 하구 인구에 의해 감소했다는 조사한 3개의 다른 서식지 지역의 다양한 저어새 개체 수 추세와 서식지 사용률을 발견했. 1991년부터 2022년까지의 대만 전지역 및 글로벌 데이터 세트에서 우리는 저어새 개체 수가 각각 연간 10.4%와10.3% 증가했음을 보여주는 선형 추세를 발견했다.가장 최근 15년 동안 이 새의 개체 수 증가율은 전 세계적으로 크게 둔화되어연간 8.4% 증가했다. 우리는 저어새를 보호하기 위해 소금 판 습지의 생물 다양성을 유지하는 것이 중요하다고 생각한다. [ABSTRACT FROM AUTHOR]

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Insufficient knowledge about the occurrence and spread of non‐native fish in mountain regions has impeded effective management strategies worldwide. To address this gap, this study analysed over 1300 electrofishing surveys across 650 sites, encompassing a vast 7400 km2 area in the Eastern Alps. The primary objectives were to quantify the occurrence of non‐native species and predict their spread in different river types. Furthermore, the study estimated population sizes and biomass trends for over 150 sites that were surveyed multiple times between 2000 and 2020. Out of the 42 fish species in the study region, 11 were identified as non‐native. Notably, two invasive species of Union concern, Lepomis gibbosus and Pseudorasbora parva, increased their population sizes by 8% and 9% per year, over the past decades, supposedly supported by increasing water temperatures. Among the non‐native species relevant for recreational fishing, Oncorhynchus mykiss populations showed a significant increase of approximately 7% per year, Salmo trutta populations remained stable, and Salvelinus fontinalis populations experienced a notable decline of approximately 7.4% per year. These varying population trends may be attributed to disparities in stocking intensities, with S. fontinalis receiving minimal stocking compared to the other species. This study revealed that non‐native and invasive fish species are a relevant part of fish communities in mountain rivers. Non‐salmonid non‐natives thrive in warm rivers at lower elevations, whereas salmonid non‐natives consolidate in steeper habitats. Because rising temperatures in mountain rivers will accelerate the spread and growth of these species, this first quantification of the current extent will improve fish management strategies in mountainous areas. [ABSTRACT FROM AUTHOR]

Conservation of biodiversity relies heavily on protected areas but their role and effectiveness under a warming climate is still debated. We estimated the climate‐driven changes in the temperature niche compositions of bird communities inside and outside protected areas in southern Canada. We hypothesized that communities inside protected areas include a higher proportion of cold‐dwelling species than communities outside protected areas. We also hypothesized that communities shift to warm‐dwelling species more slowly inside protected areas than outside. To study community changes, we used large‐scale and long‐term (1997–2019) data from the Breeding Bird Survey of Canada. To describe the temperature niche compositions of bird communities, we calculated the community temperature index (CTI) annually for each community inside and outside protected areas. Generally, warm‐dwelling species dominated communities with high CTI values. We modeled temporal changes in CTI as a function of protection status with linear mixed‐effect models. We also determined which species contributed most to the temporal changes in CTI with a jackknife approach. As anticipated, CTI was lower inside protected areas than outside. However, contrary to our expectation, CTI increased faster over time inside than outside protected areas and warm‐dwelling species contributed most to CTI change inside protected areas. These results highlight the ubiquitous impacts of climate warming. Currently, protected areas can aid cold‐dwelling species by providing habitat, but as the climate warms, the communities' temperature compositions inside protected areas quickly begin to resemble those outside protected areas, suggesting that protected areas delay the impacts of climate warming on cold‐dwelling species. [ABSTRACT FROM AUTHOR]

Harlequin Duck (Histrionicus histrionicus) is a small sea duck that winters in coastal waters and breeds on fast-moving mountain streams in western North America. Because of its dependency on streams and coastal near-shore habitat with healthy macroinvertebrate populations, population trends of this species can be used as an indication of healthy freshwater and marine ecosystems. From 1995 to 2020 we conducted roadside surveys for Harlequin Ducks on the Bow River in Banff National Park, Alberta. We calculated the population's trend by modelling maximum annual count, which showed a population decline over the 25 years of 3.3% per year. The trajectory varied over time: a relatively stable population from 1995 to 2005, a steep decline until 2011, then stabilising at a much lower level with a slight rebound in recent years. The predicted number of ducks from our state-space model closely tracked the maximum number of ducks observed in annual counts. During stable or slightly increasing population estimates the male:female (M:F) ratio fluctuated considerably but stayed high (1.4:1 and 1.3:1, respectively), and during the period of steep population decline the M:F ratio was at its lowest (1.1:1). This declining population trend is concerning because it is occurring in a protected area, but it is similar to data from other studies in the Rocky Mountains and at the coastal wintering area, suggesting that causes may not be solely due to issues on the breeding streams. [ABSTRACT FROM AUTHOR]

Ecological succession creates a sequence of habitat types after an initial disturbance. In Central Europe, these types typically include a gradient of stages from bare ground to forest. Ecological communities differ between habitat types because some species are associated with a given type along the gradient. The conservation status of these communities provides information about environmental pressures acting upon the respective habitat types. Here, we focused on birds and compared three measures of their conservation status, namely population trend, Red List category, and legal protection, expressed at two different levels, national and European, among the habitat types. We used data from the mapping of breeding bird occurrences in 42 abandoned military training sites in Czechia covering the entire successional gradient. In these areas, we identified 423 habitat polygons, each representing one of the following habitat types: bare ground, grassland, sparse scrubland, dense scrubland and forest. In general, birds recorded in forest had the most favorable conservation status, while birds recorded on bare ground and grassland had the least favorable; birds of both types of scrublands showed intermediate values. This corresponds to recent findings of the suitability of forest management for bird populations in Central Europe on the one hand and the adverse impacts of various changes in the human use of open habitats on the other. We observed a general agreement in the different measures, indicating that population trends are likely used for Red List categorization, which further serves to select species for legal protection. However, exceptions to this general pattern suggest that the listing and establishment of legal protection do not adequately reflect population changes and need more frequent updating. [ABSTRACT FROM AUTHOR]

Introduction: Anatidae family is considered as a biological indicator of wetlands due to their migratory behavior, wide distribution and high population density. Three wetlands of the Bakhtegan basin, namely Bakhtegan, Tashk and Kamjan in Fars province, are important habitats for Anatidae in the central plateau of Iran. The purpose of this research was to evaluate fluctuations in the wintering population of the Anatidae family in wetlands of the Bakhtegan basin in a long-term period of 52 years from 1967 to 2018.Material and methods: Data on the population and diversity of waterbirds were obtained from a 52-year census data of the Department of the Environmental of Iran. Results of field studies in 2019 were also used to investigate their current habitat condition, data validation and monitoring of Anatidae populations. Of 21 Anatidae species recorded in Iran, nine species with a population of more than 50 individuals per year and observed at least 20 years, were investigated along with the Vulnerable species (VU) of Common Pochard Aythya ferina. Annual changes in the total population of waterbirds, the number of species in each year, the proportion of Anatidae in the population and the diversity of waterbirds in Bakhtegan wetlands and the statistical trend of population changes of species were analyzed. Trend of long-term changes in the population of Anatidae species were calculated using the RTRIM statistical package and Multi-species Indicators (MSI).Results and discussion: A total of 21 of Anatidae species, including Endangered species (EN) of White-headed Duck Oxyura leucocephala, Marbled Duck Marmaronetta angustirostris (VU) and Common Pochard (VU) and Near Threatened species (NT) of Ferruginous Duck Aythya nyroca were identified in the wetlands of Bakhtegan basin. The average population of Anatidae in a 31-year period (1988–2008) was more than 169,000 individuals, but in the last ten years (2009–2018), it decreased to 6,623 individuals. The highest number of total population was in 1995 with 632,510 individuals and the lowest with 1,135 individuals in 2016. The highest and lowest number of species were in 2000 and 2010 with 13 and 3 species, respectively. The statistical trend of the population changes showed that the Greylag Goose Anser anser faced a steep decline in the long-term with a slope of -21%, the Shelduck Tadorna tadorna with a steep decline (-8.4%), the Ruddy Shelduck Tadorna ferruginea with a stable population and zero percent, the Mallard Anas platyrhynchos and the Eurasian Teal Anas crecca with a steep decline and slope of -12.1% and -6.5%, respectively. Trend of changes in the last ten years for the Greylag Goose was stable (0.1%), Shelduck with an uncertain state (4.8%), Ruddy Shelduck and Mallard with a decrease and a slop of -3.8% and -9.4%, respectively, and Eurasian Teal with a strong increase (48.9%). The results indicate that Bakhtegan wetlands had a high proportion of waterbirds during the 1990s to the early 2000s, but it has lost its position in the last 15 years. Bakhtegan wetlands used to be the breeding habitat for Marbled Ducks, but there have been no reports of its breeding in recent years.The reduction of water level, drying wet areas and changes in habitat variables have been the most important factors in reduction of the population and diversity of Anatide species.Conclusion: The Anatidae family has more than 30% of species diversity and more than 53% of the total population of waterbirds in Bakhtegan wetlands. Currently, it is possible for birds to spend the winter in only a small part of Tashk wetland in the area of Gamban spring. Reconstruction, restoration and making continuous and effective protection of the wetland chain of Bakhtegan Basin requires allocating the required water from diverse water sources for its biological sustainability. In the case of increasing the level and depth of these water areas, the possibility of increasing the population and diversity of diving ducks and Mergus species is expected. Due to the importance of the participation of stakeholders in the protection and restoration of wetlands, it is necessary to take action regarding the allocation of biological water rights and participatory protection of wetlands according to the social, economic, cultural and political conditions.

Deforestation is perhaps the greatest threat to tropical biodiversity. Anyway, extensive areas in the tropics have naturally regenerated and become secondary forests, which might mitigate biodiversity loss. However, evidence about the value of secondary forests for biodiversity conservation is still controversial. To establish the conservation value of secondary forests in the tropical Andes, we compared bird species richness, abundance, and composition between old and mature secondary forests using camera traps for two consecutive years. Our results suggest that old and mature secondary forests are similar in species richness and abundance to mature secondary forests, but these habitats significantly differ in species composition. Old secondary forests harbored some species highly specialized to mature forests (e.g., ant-following insectivorous birds: Myrmeciza longipes, Gymnopithys bicolor, Formicarius analis, and Dendrocincla fuliginosa) that are highly sensitive to habitat disturbance. Additionally, old secondary forests constitute suitable habitat for several species with decreasing populations, which could become of conservation importance in the long run. We consider that old secondary forests surrounded by mature forests can contribute to conserving understory birds, one of the most susceptible groups, negatively affected by tropical forest loss and degradation. Therefore, strategies for habitat biodiversity protection in this region should also include old secondary forests.

Current assessments indicate that populations of several species of North American shorebirds are declining rapidly. However, limited monitoring programs south of the U.S.-Mexico border have precluded assessments of the conservation status of temperate breeders on their principal wintering grounds. The Migratory Shorebird Project (MSP), active since 2011 throughout the Pacific Americas Flyway, provides an opportunity to detect changes in non-breeding shorebird distribution and abundance. We used annual survey data collected using the MSP monitoring protocol to assess population trends of three temperate breeders: Marbled Godwit (Limosa fedoa), Willet (Tringa semipalmata), and Long-billed Curlew (Numeniues americanus) on their main wintering grounds in northwest Mexico and California. We also analyzed the associations between fluctuations in their abundance and environmental variables using Generalized Linear Mixed Models. We found a significant negative trend in the wintering population of Marbled Godwit and Willet in California and the Baja California Peninsula (BCP). The BCP was the most important region for these three species in the study area, followed by Sonora, Sinaloa, Nayarit (SSN), and California. In addition, we determined that Marbled Godwit abundance was negatively associated with precipitation and positively associated with minimum temperature from January. Willet abundance also was positively associated with minimum temperature, but negatively with sea surface temperature and precipitation. Association of Long-billed Curlew abundance with precipitation was positive and significant. Our study provides evidence that temperate shorebirds are declining and their fluctuations are associated to environmental variables, and highlights the importance of long-term winter shorebird surveys for understanding drivers of populations change that can then be used to identify management and adaptation strategies.

The Tarim red deer Cervus hanglu has been recently recognized as a separate deer species with populations in China, Central Asia and Kashmir. These populations are few, isolated and at risk of extinction. The documented range of the Kashmir population of the hangul, now recognized as Cervus hanglu hanglu , is restricted to c. 808 km2 and comprises < 200 individuals, confined mainly to the 141 km2 Dachigam National Park. A few relict herds inhabit the surrounding landscape. Here we analyse the results of almost 20 years of population monitoring (January 2001–March 2020). We found that this population is unable to increase despite full protection within Dachigam National Park. We performed a population viability analysis using both deterministic and stochastic simulations and found that further population decrease is likely. We recommend the use of improved monitoring methods to investigate the population dynamics of the hangul and the implementation of measures to reduce the risk of extinction faced by this small population. Science-based conservation policies, including ex situ conservation and reintroduction programmes, will be required to increase the hangul population size and range. [ABSTRACT FROM AUTHOR]