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Context: Habitat connectivity can stabilise animal populations by facilitating immigration and genetic exchange, but it increases the risk of infectious diseases being spread by hosts. Chytridiomycosis caused by Batrachochytrium salamandrivorans (Bsal) threatens European salamander diversity. The extent to which the connectivity of populations of fire salamanders (Salamandra salamandra) contributes to the spread of Bsal remains unclear. Objectives: We analysed the impact of habitat connectivity of fire salamanders on the spread of Bsal. Moreover, we show how local salamander abundance is associated with habitat connectivity over a five-year period. Methods: We developed fire salamander habitat suitability models (HSMs) for the Eifel area (Germany), currently considered the core of the range of Bsal in Europe. Habitat models were used to calculate pairwise resistance between salamander occurrences to test whether Bsal presence and salamander abundance were associated with habitat connectivity. Results: Fire salamanders are widely distributed in the Eifel. Solid bedrock and topographic positioning were important predictors of stream suitability as breeding habitats, while deciduous forests and grassland cover determined overall fire salamander habitat suitability along with breeding habitat suitability. Bsal-positive salamander occurrences were better-connected than Bsal-negative or untested occurrences. Nevertheless, fire salamander larvae were more abundant in well-connected sites. Conclusion: The connection of salamander populations by suitable habitat seems to support local salamander abundance while facilitating the spread of Bsal. In situ conservation measures counteracting host species connectivity to interrupt Bsal transmission pathways must be implemented with caution, as they may weaken the demographic advantages of connectivity. [ABSTRACT FROM AUTHOR]

Long-term analyses of biodiversity data highlight a ‘biodiversity conservation paradox’: biological communities show substantial species turnover over the past century1,2, but changes in species richness are marginal1,3–5. Most studies, however, have focused only on the incidence of species, and have not considered changes in local abundance. Here we asked whether analysing changes in the cover of plant species could reveal previously unrecognized patterns of biodiversity change and provide insights into the underlying mechanisms. We compiled and analysed a dataset of 7,738 permanent and semi-permanent vegetation plots from Germany that were surveyed between 2 and 54 times from 1927 to 2020, in total comprising 1,794 species of vascular plants. We found that decrements in cover, averaged across all species and plots, occurred more often than increments; that the number of species that decreased in cover was higher than the number of species that increased; and that decrements were more equally distributed among losers than were gains among winners. Null model simulations confirmed that these trends do not emerge by chance, but are the consequence of species-specific negative effects of environmental changes. In the long run, these trends might result in substantial losses of species at both local and regional scales. Summarizing the changes by decade shows that the inequality in the mean change in species cover of losers and winners diverged as early as the 1960s. We conclude that changes in species cover in communities represent an important but understudied dimension of biodiversity change that should more routinely be considered in time-series analyses.Time-series data including 1,794 plant species from 7,738 vegetation plots in Germany between 1927 and 2020 reveal patterns of change in biodiversity, and suggest that more species declined than increased in abundance during this period. [ABSTRACT FROM AUTHOR]

Detecting species trends across different habitat types and larger regions is required to generate a general and reliable foundation for conservation planning. While direct monitoring data covering a large spatial and temporal extent are mostly lacking, data collected for other purposes than monitoring can be considered to detect trends. Here we analyzed both habitat type and plant species trends over several decades (1979–2017), using repeated habitat survey data from the habitat mapping program of the city and federal state of Hamburg. Next to transitions between habitat types, we looked for differences between winner and loser species, considering also their habitat type preference, red list, and non‐native status. Furthermore, we assessed the consistency between trends of habitat types and species that are characteristic of those habitat types. We found declines in habitat area of semi‐natural (semi‐)dry grasslands and semi‐ruderal vegetation and increases in habitat area of species‐poor grasslands, pioneer forests, and human settlements. More species showed positive than negative trends over time, with winners including many forest and scrub as well as non‐native species, while losers were represented mostly by endangered and ruderal species. Most habitat types included a mixture of both winner and loser species. Habitat type trends were mostly not reflected in trends of species that were characteristic of a particular habitat, such as semi‐natural (semi‐)dry grasslands. This can be explained, on the one hand, by species extinction debts, and on the other hand, by a low habitat specificity of some species that find refuges also in secondary habitats. Our study not only shows the difficulties but also offers methods on how to use repeated habitat mapping data to detect trends for habitat types and plant species. In contrast to monitoring programs focusing on individual endangered habitats, results from repeated habitat surveys allow the identification of those secondary habitats of a species that might contribute the most to preserving populations of their primary habitat. [ABSTRACT FROM AUTHOR]

Large‐scale biodiversity databases have great potential for quantifying long‐term trends of species, but they also bring many methodological challenges. Spatial bias of species occurrence records is well recognized. Yet, the dynamic nature of this spatial bias – how spatial bias has changed over time – has been largely overlooked. We examined the spatial bias of species occurrence records within multiple biodiversity databases in Germany and tested whether spatial bias in relation to land cover or land use (urban and protected areas) has changed over time. We focused our analyses on urban and protected areas as these represent two well‐known correlates of sampling bias in biodiversity datasets. We found that the proportion of annual records from urban areas has increased over time while the proportion of annual records within protected areas has not consistently changed. Using simulations, we examined the implications of this changing sampling bias for estimation of long‐term trends of species' distributions. When assessing biodiversity change, our findings suggest that the effects of spatial bias depend on how it affects sampling of the underlying land‐use change drivers affecting species. Oversampling of regions undergoing the greatest degree of change, for instance near human settlements, might lead to overestimation of the trends of specialist species. For robust estimation of the long‐term trends in species' distributions, analyses using species occurrence records may need to consider not only spatial bias, but also changes in the spatial bias through time. [ABSTRACT FROM AUTHOR]

Citizen scientists play an increasingly important role in biodiversity monitoring. Most of the data, however, are unstructured—collected by diverse methods that are not documented with the data. Insufficient understanding of the data collection processes presents a major barrier to the use of citizen science data in biodiversity research. We developed a questionnaire to ask citizen scientists about their decision-making before, during and after collecting and reporting species observations, using Germany as a case study. We quantified the greatest sources of variability among respondents and assessed whether motivations and experience related to any aspect of data collection. Our questionnaire was answered by almost 900 people, with varying taxonomic foci and expertise. Respondents were most often motivated by improving species knowledge and supporting conservation, but there were no linkages between motivations and data collection methods. By contrast, variables related to experience and knowledge, such as membership of a natural history society, were linked with a greater propensity to conduct planned searches, during which typically all species were reported. Our findings have implications for how citizen science data are analysed in statistical models; highlight the importance of natural history societies and provide pointers to where citizen science projects might be further developed. [ABSTRACT FROM AUTHOR]

Remote sensing (RS) enables a cost-effective, extensive, continuous and standardized monitoring of traits and trait variations of geomorphology and its processes, from the local to the continental scale. To implement and better understand RS techniques and the spectral indicators derived from them in the monitoring of geomorphology, this paper presents a new perspective for the definition and recording of five characteristics of geomorphodiversity with RS, namely: geomorphic genesis diversity, geomorphic trait diversity, geomorphic structural diversity, geomorphic taxonomic diversity, and geomorphic functional diversity. In this respect, geomorphic trait diversity is the cornerstone and is essential for recording the other four characteristics using RS technologies. All five characteristics are discussed in detail in this paper and reinforced with numerous examples from various RS technologies. Methods for classifying the five characteristics of geomorphodiversity using RS, as well as the constraints of monitoring the diversity of geomorphology using RS, are discussed. RS-aided techniques that can be used for monitoring geomorphodiversity in regimes with changing land-use intensity are presented. Further, new approaches of geomorphic traits that enable the monitoring of geomorphodiversity through the valorisation of RS data from multiple missions are discussed as well as the ecosystem integrity approach. Likewise, the approach of monitoring the five characteristics of geomorphodiversity recording with RS is discussed, as are existing approaches for recording spectral geomorhic traits/ trait variation approach and indicators, along with approaches for assessing geomorphodiversity. It is shown that there is no comparable approach with which to define and record the five characteristics of geomorphodiversity using only RS data in the literature. Finally, the importance of the digitization process and the use of data science for research in the field of geomorphology in the 21st century is elucidated and discussed. [ABSTRACT FROM AUTHOR]

Christensen et al. criticized the application of Beals' index of sociological favourability to adjust for incomplete species lists when comparing repeated surveys. Their main argument was that using Beals' conditional occurrence probabilities would systematically underestimate biodiversity change compared to using observed frequencies. Although this might be the case for rare species, as we explicitly stated in our original publication, we here use a worked‐out example to show that this criticism is unjustified for species that are sufficiently represented in the reference data set. In our opinion, the misconception derives from ignoring one of the key requirements for applying Beal's index, which is the use of a sufficiently large reference data set to derive a reliable co‐occurrence matrix. We here show how the predicted probability for the occurrence of a species depends on the size of the reference data set and give recommendations on the premises for applying Beals' approach for monitoring purposes. [ABSTRACT FROM AUTHOR]

Efficient biodiversity conservation requires that limited resources be allocated in accordance with national responsibilities and priorities. Without appropriate computational tools, the process of determining these national responsibilities and conservation priorities is time intensive when considering many species across geographic scales. Here, we have developed a computational tool as a module for the ArcGIS geographic information system. The ArcGIS National Responsibility Assessment Tool (NRA-Tool) can be used to create hierarchical lists of national responsibilities and priorities for global species conservation. Our tool will allow conservationists to prioritize conservation efforts and to focus limited resources on relevant species and regions. We showcase our tool with data on 258 bird species and various biophysical regions, including Environmental Zones in 58 Asian countries and regions. Our tool provides a decision support system for conservation policy with attractive and easily interpretable visual outputs illustrating national responsibilities and priorities for species conservation. The graphical output allows for smooth integration into assessment reports, such as the European Article 17 report, the Living Planet Index report, or similar regional and global reports. [ABSTRACT FROM AUTHOR]

The risk of collision with wind turbines remains a critical issue for bird conservation. Undoubtedly, for the continued development of wind farms to increase the energy capacity, wind farm locations must be carefully chosen going forward. This can be achieved not only by avoiding areas with higher bird densities but also by avoiding installations at sensitive distances from their ecologically important land‐use types. Through analyses of the Euclidean distances to the different land‐use types, we utilized the random forest (RF) machine learning algorithm to model the distance‐based impacts of wind turbine locations on detected bird collisions for the frequently‐hit groups of birds at WTs. Although, the predicted areas with potential collision risk in total had a small but highly dispersed expanse of ~2,130 km2 across the vast 29,479 km2 area of the federal state. Our results further segregated these assessed areas based on their different probabilities of collision thresholds (between 0 and 1) to only detect the areas with collision probabilities <.05, which were interpreted as the actual "no risk areas". These "no risk areas" summed to a total of merely 754 km2 of the land space in Brandenburg, suggesting that any further planned additions of wind energy farms in the state that is, the proposed wind turbines, to be suitably positioned only in these safer areas. Additionally, the study also enabled the identification of any existing wind turbines already installed in the remaining less safe 28,725 km2 area of the state. These areas are also essential to be include in the collision detection surveys and bird population dynamic studies. This would further our understanding regarding the deleterious consequences of collisions at the population levels of birds, eventually helping in the formulation of adequate mitigation measures. [ABSTRACT FROM AUTHOR]

With the increase in wind turbines, bird collisions have developed as a potential hazard. In the federal state of Brandenburg, Germany, despite the on-going mitigation efforts of increasing the distances of wind turbines from the breeding areas of the more severely affected populations of red kites (Milvus milvus), the additional detrimental influences on the buzzard populations (Buteo buteo) have added to the challenges for wind power expansion. Using data on the regional distribution of the buzzards, along with their carcass detections around the wind turbines (WTs), we aimed to better understand their collision distribution patterns in relation to their habitat use patterns to predict their exposure to collision risk using boosted regression trees (BRTs). Additionally, we integrated the developed collision potential map with the regional density map of buzzards to identify areas of increased strike susceptibility in turbine installations. Our study showed that the buzzard collisions were primarily concentrated at the turbines situated at sensitive distances from the edges of watercourses (>1000 metres), as well as those along the edges of grasslands (>750 metres), in the green open areas around/areas with minimal settlements (750 metres-1750 metres), and along the edges of bushlands (>1500 metres), together explaining 58% of the variance in their collision distribution. Conclusively, our study is applicable to conservation because it demonstrates the identification of potential collision areas along with the causes of the collisions, in addition to demonstrating the benefits of incorporating a species collision dataset as a proxy for species presence into species distribution models to make informed management decisions to eventually combat biodiversity loss. [ABSTRACT FROM AUTHOR]

Ecology often faces the problem that many threatened species are highly elusive but also conflict-laden. Thus, proper monitoring data are inevitable for their conservation and management. Indirect monitoring through scats is frequently used for such species, but scats of related species or species with similar diet are often visually indistinguishable. Since genetic methods for species identification are time-consuming and cost-intensive, a verification of the target species beforehand would be extremely beneficial in reducing effort to the analysis of the target species only. Such species discrimination could be provided through speciesspecific scat detection dogs. Therefore, we evaluated the reliability of species-specific scat detection dogs for two mustelid species feeding on identical diets: the Eurasian otter (Lutra lutra) and the American mink (Neovison vison), both of which are conflict-laden and increasing their populations and distribution ranges in central Europe. Their scats resemble each other in morphology and odour, exacerbating the differentiation even for experts. To evaluate whether detection dogs can reliably discriminate between related species feeding on similar diets and if their use would be beneficial, we tested their abilities against those of humans. We first proved that scat characteristics are not statistically different between species. Likewise, visual species identification through people with different experience levels was only partly successful. Experts showed higher average accuracy (0.89) than non-experts (0.72 and below), but detection dogs (4 dogs) were able to discriminate otter and mink scats under laboratory conditions with an accuracy of 0.95. Moreover, otter scat detection dogs found up to four times more scat samples in the field, were twice as fast as human searchers and found an almost equal number of scats with different characteristics, while humans mostly found older and larger scats placed on hotspots. We conclude that using detection dogs for species identity will allow subsequent laboratory analyses to be species-specific and avoid spending time and money on laboratory work of the wrong species. It also provides more precise and unbiased information about the target species. [ABSTRACT FROM AUTHOR]

Artificial light at night (LAN) has become a stressor of global extent. Previous work has highlighted the high potential of LAN to interfere with annual and diel rhythms of seasonal organisms as well as to affect interactions at the community level. However, our understanding how LAN induced alterations of activity and breeding cycles affect the reproductive outcome and fitness of the birds is still limited. Here, we focus on the effects of night time illumination on the breeding biology of urban European blackbirds Turdus merula. Our results indicate that blackbirds prefer illuminated nest sites and advance their date of clutch initiation by 6 d per 1 lux of night time illumination. Furthermore, daily nest survival rates increased with increasing LAN although this effect was most pronounced for the transition from dark to slightly illuminated sites. We suggest that blackbirds breeding under low artificial night light conditions benefit from the LAN-avoidance of their major predators (nocturnal) whereas predominant predators of blackbirds nesting in the city centre are diurnal and are, thus, not affected by LAN. Hence, it seems likely that both direct effects of LAN on the timing of reproduction as well as indirect effects on interspecific interactions might contribute to the observed changes in the breeding biology of European blackbirds. This study emphasizes the diverse ecological effects of the night time illumination which are - in its complexity - still poorly understood. [ABSTRACT FROM AUTHOR]

Nature conservation policies need to deliver on multiple criteria, including genetic diversity, population viability and species richness as well as ecosystem services. The challenge of integrating these may be addressed by simulation modelling., We used four models (MetaConnect, SPOMSIM, a community model and In VEST) to assess a variety of spatial habitat patterns with two levels of total habitat cover and realised at two spatial scales, exploring which landscape structures performed best according to five different conservation criteria assessed for four functional types of organisms (approximately representing trees, butterflies, small mammals and birds)., The results display both synergies and trade-offs: population size and pollination services generally benefitted more from fragmentation than did genetic heterozygosity, and species richness more than allelic richness, although the latter two varied considerably among the functional types., No single landscape performed best across all conservation criteria, but averaging over criteria and functional types, overall performance improved with greater levels of habitat cover and intermediate fragmentation (or less fragmentation in cases with lower habitat cover)., Policy implications. Using four simulation models, we show that different conservation objectives must be traded off in spatial conservation planning, and that considering only a single taxon or criterion may result in suboptimal choices when planning reserve networks. Nevertheless, heterogeneous spatial patterns of habitat can provide reasonable compromises for multiple criteria. [ABSTRACT FROM AUTHOR]

In order to maximize their fitness, organisms in seasonal environments rely on external cues to optimally time their life-history stages. One of the most important zeitgeber to time reproduction is the photoperiod, but further environmental cues are assessed to fine-tune reproduction due to year-to-year variation in environmental conditions. However, in urbanized environments, the pervasive artificial light at night has altered the natural signal of light and darkness. Accordingly, artificial light at night was repeatedly shown to affect avian reproductive physiology and to advance seasonal reproduction in birds. However, these experiments were mainly conducted in the absence of further environmental cues to facilitate the investigation of the mechanisms which are still poorly understood. Here, we investigate whether the endocrine system of freeranging European blackbirds (Turdus merula) correlates with the amount of artificial light at night along a rural to urban gradient while the birds still encounter complementary environmental cues including seasonal variation in day length and temperature. Testosterone and estrone were assessed as metabolites in fecal samples and corticosterone in blood from mist-netted blackbirds. We demonstrate that seasonal fluctuations in abiotic factors, individual conditions, but also light at night affect the reproductive and stress physiology of wild European blackbirds. Elevated artificial night light intensities were significantly positively correlated with corticosterone and negatively with female estrone levels. No effects of artificial light were found for testosterone levels. Our results suggest that female blackbirds in particular perceive even low levels of artificial light at night as a weak but chronic stressor that interacts with the hypothalamic-pituitary-gonadal axis and leads to a reduced secretion of reproductive hormones. These findings point out that the impacts of light pollution are diverse and we only slowly disentangle its multiple effects on physiology, ecology, and biodiversity. [ABSTRACT FROM AUTHOR]

Artificial light at night (ALAN) is one of the most obvious hallmarks of human presence in an ecosystem. The rapidly increasing use of artificial light has fundamentally transformed nightscapes throughout most of the globe, although little is known about how ALAN impacts the biodiversity and food webs of illuminated ecosystems. We developed a large-scale experimental infrastructure to study the effects of ALAN on a light-naïve, natural riparian (i.e., terrestrial-aquatic) ecosystem. Twelve street lights (20 m apart) arranged in three rows parallel to an agricultural drainage ditch were installed on each of two sites located in a grassland ecosystem in northern Germany. A range of biotic, abiotic, and photometric data are collected regularly to study the short- and long-term effects of ALAN on behavior, species interactions, physiology, and species composition of communities. Here we describe the infrastructure setup and data collection methods, and characterize the study area including photometric measurements. None of the measured parameters differed significantly between sites in the period before illumination. Results of one short-term experiment, carried out with one site illuminated and the other acting as a control, demonstrate the attraction of ALAN by the immense and immediate increase of insect catches at the lit street lights. The experimental setup provides a unique platform for carrying out interdisciplinary research on sustainable lighting. [ABSTRACT FROM AUTHOR]

Quantifying population status is a key objective in many ecological studies, but is often difficult to achieve for cryptic or elusive species. Here, non-invasive genetic capture-mark-recapture (CMR) methods have become a very important tool to estimate population parameters, such as population size and sex ratio. The Eurasian otter (Lutra lutra) is such an elusive species of management concern and is increasingly studied using faecal-based genetic sampling. For unbiased sex ratios or population size estimates, the marking behaviour of otters has to be taken into account. Using 2132 otter faeces of a wild otter population in Upper Lusatia (Saxony, Germany) collected over six years (2006–2012), we studied the marking behaviour and applied closed population CMR models accounting for genetic misidentification to estimate population sizes and sex ratios. We detected a sex difference in the marking behaviour of otters with jelly samples being more often defecated by males and placed actively exposed on frequently used marking sites. Since jelly samples are of higher DNA quality, it is important to not only concentrate on this kind of samples or marking sites and to invest in sufficiently high numbers of repetitions of non-jelly samples to ensure an unbiased sex ratio. Furthermore, otters seemed to increase marking intensity due to the handling of their spraints, hence accounting for this behavioural response could be important. We provided the first precise population size estimate with confidence intervals for Upper Lusatia (for 2012: = 20 ± 2.1, 95% CI = 16–25) and showed that spraint densities are not a reliable index for abundances. We further demonstrated that when minks live in sympatry with otters and have comparably high densities, a non-negligible number of supposed otter samples are actually of mink origin. This could severely bias results of otter monitoring if samples are not genetically identified. [ABSTRACT FROM AUTHOR]

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ABSTRACT The main goal of non-invasive genetic capture-mark-recapture (CMR) analysis is to gain an unbiased and reliable population size estimate of species that cannot be sampled directly. The method has become an important and widely used tool to research and manage wildlife populations. However, researchers have to struggle with low amplification success rates and genotyping errors, which substantially bias subsequent analysis. To receive reliable results and to minimize the time and costs required for non-invasive microsatellite genotyping, one must carefully choose a species-specific sampling design, methods that maximize the amount of template DNA, and methods that could overcome genotyping errors, especially when using low-quality samples. This article reviews the literature and the pros and cons of the main methods used along the process described above. The review is strengthened by a case study on Eurasian otters ( Lutra lutra) using feces; we tested several methods for their appropriateness to accommodate for genotyping errors. Based on this method testing, we demonstrated that high genotyping error rates are the key problem in this process leading to a severely flawed dataset if no consensus genotype is formed. However, even if generating consensus genotypes minimizes errors dramatically, we show that it may not achieve a definite eradication of all errors, which results in overestimated population sizes if conventional estimators are used. In conjunction with these findings, we offer a step-by-step protocol for non-invasive genetic CMR studies to achieve a reliable estimate of population sizes in the presence of high genotyping error rates. © 2013 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Organisms living in urban environments are exposed to different environmental conditions compared to their rural conspecifics. Especially anthropogenic noise and artificial night light are closely linked to urbanization and pose new challenges to urban species. Songbirds are particularly affected by these factors, because they rely on the spread of acoustic information and adjust their behaviour to the rhythm of night and day, e.g. time their dawn song according to changing light intensities. Our aim was to clarify the specific contributions of artificial night light and traffic noise on the timing of dawn song of urban European Blackbirds (Turdus merula). We investigated the onset of blackbird dawn song along a steep urban gradient ranging from an urban forest to the city centre of Leipzig, Germany. This gradient of anthropogenic noise and artificial night light was reflected in the timing of dawn song. In the city centre, blackbirds started their dawn song up to 5 hours earlier compared to those in semi-natural habitats. We found traffic noise to be the driving factor of the shift of dawn song into true night, although it was not completely separable from the effects of ambient night light. We additionally included meteorological conditions into the analysis and found an effect on the song onset. Cloudy and cold weather delayed the onset, but cloud cover was assumed to reflect night light emissions, thus, amplified sky luminance and increased the effect of artificial night light. Beside these temporal effects, we also found differences in the spatial autocorrelation of dawn song onset showing a much higher variability in noisy city areas than in rural parks and forests. These findings indicate that urban hazards such as ambient noise and light pollution show a manifold interference with naturally evolved cycles and have significant effects on the activity patterns of urban blackbirds. [ABSTRACT FROM AUTHOR]

1. Visitation rate is a measure of the frequency with which animals visit specific locations of interest. This information is crucial for various problems in the conservation and management of animal species, e.g. to determine the risk wildlife poses to human managed resources or the predation risks of nests. An important assessment tool, especially for cryptic animals, is to count indirect signs of presence, such as tracks or faeces. 2. Here we propose a maximum likelihood-based method that uses information on the age of tracks or signs, and we show that existing visitation rate/probability estimators are special cases of this more general approach. 3. Using simulated data, we compared the performance of the new visitation rate estimator to three other estimators, including the most commonly used estimator. These estimators make use of either fresh, aged or total signs, whereas our approach uses information simultaneously on both fresh and aged signs. The new estimator is, on average, in excess of three times more accurate than the next best estimator. Moreover, the new approach is very flexible and can be applied for sampling regimens with irregular time intervals between sampling. 4. We demonstrate the application of the method to field data by estimating the visitation rate of Eurasian otters ( Lutra lutra) to a commercial fish pond. To facilitate the use of this method, we provide an easy-to-use Excel workbook and give recommendations on the most efficient sampling regimens. 5. Synthesis and applications. Visitation rate is an important quantity that can be estimated by repetitive sampling of indirect signs. We demonstrate the advantage of incorporating information explicitly on the age of signs over existing approaches. The new estimator can be applied to any species for which it is possible to discriminate between aged and new signs or tracks, and should be widely applicable in ecology and conservation biology. [ABSTRACT FROM AUTHOR]

The article focuses on the study on how to manage the emerging conflict between wildlife and humans on resource use. It notes that in many parts in Europe, the improved nature conservation have resulted in the growing occupancy of animal species. The scientist have predicted the scenario to ignite the old conflicts between humans and wildlife in terms of resources consumption. It mentions that the conflict between wildlife and humanities are inevitable because species like otter, wolf, and seals will continue to compete for food. The conflict solutions are said to be simple and do not necessarily have to be expensive such as simple farming methods that can prevent serious losses.

In long–lived social mammals such as primates, individuals can benefit from social bonds with close kin, including their mothers. In the patrilocal chimpanzee (Pan troglodytes spp.) and bonobo (Pan paniscus), sexually mature males reside and reproduce in their natal groups and can retain post-dependency bonds with their mothers, while immatures of both sexes might also have their paternal grandmothers available. However, quantitative information on the proportion of males and immatures that co-reside with both types of these close female relatives is limited for both species. Combining genetic parentage determination and group composition data from five communities of wild chimpanzees and three communities of wild bonobos, we estimated the frequency of co-residence between (1) mature males and their mothers, and (2) immature males and females and their paternal grandmothers. We found that adult males resided twice as frequently with their mothers in bonobos than in chimpanzees, and that immature bonobos were three times more likely to possess a living paternal grandmother than were immature chimpanzees. Patterns of female and male survivorship from studbook records of captive individuals of both species suggest that mature bonobo females survive longer than their chimpanzee counterparts, possibly contributing to the differences observed in mother–son and grandmother–immature co-residency levels. Taking into account reports of bonobo mothers supporting their sons' mating efforts and females sharing food with immatures other than their own offspring, our findings suggest that life history traits may facilitate maternal and grandmaternal support more in bonobos than in chimpanzees. [ABSTRACT FROM AUTHOR]