1,720,958 research outputs found
Sweet mama: Affiliative interactions are related to the reproductive success of dominant female Alpine Marmots (Marmota marmota)
Full text linkThe version of record of this article, first published in [Journal of Ethology], is available online at Publisher’s website: http://dx.doi.org/10.1007/s10164-024-00825-5Sociality is a complex phenomenon, able to influence multiple traits of an individual life history. In group-living mammals, sociality is likely to play a major role in the reproductive success of individuals. Here we investigate how sociality traits are associated to reproductive success in female Alpine marmots (Marmota marmota), a highly social and cooperative breeding ground squirrel distributed in the European Alps. We used social network analysis to calculate sociality metrics and hurdle generalized linear mixed models (hurdle GLMMs) to model the relationship between sociality metrics and reproductive success of individually tagged female Alpine marmots. Our results showed that centrality of a reproductive female within her social group and the number of social partners are positively related to reproductive success, while agonistic behavior was not related with reproduction. Our results highlight the importance of affiliative interactions with other group members in cooperative breeders, suggesting that in such systems female fitness could be more related to social cohesion than to costs of agonistic behaviors to maintain dominance status.Unfunde
Monitoring wildlife population trends with sample counts: a case study on the Alpine ibex (Capra ibex)
Full text linkMonitoring population dynamics is of fundamental importance in conservation but assessing trends in abundance can be costly, especially in large and rough areas. Obtaining trend estimations from counts performed in only a portion of the total area (sample counts) can be a cost‐effective method to improve the monitoring and conservation of species difficult to count. We tested the effectiveness of sample counts in monitoring population trends of wild animals, using as a model population the Alpine ibex Capra ibex in the Gran Paradiso National Park (Italy), both with computer simulations and using historical count data collected over the last 65 years. Despite sample counts failed to correctly estimate the true population abundance, sampling half of the target area could reliably monitor the trend of the target population. In case of strong changes in abundance, an even lower proportion of the total area could be sufficient to identify the direction of the population trend. However, when there is a high yearly trend variability, the required number of samples increases and even counting in the entire area can be ineffective to detect population trends. The effect of other parameters, such as which portion of the area is sampled and detectability, was lower, but these should be tested case by case. Sample counts could therefore constitute a viable alternative to assess population trends, allowing for important, cost‐effective improvements in the monitoring of wild animals of conservation interest
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
A new double observer‐based census framework to improve abundance estimations in mountain ungulates and other gregarious species with a reduced effort
Full text link© 2024 The Author(s). Ecological Solutions and Evidence published by John Wiley & Sons Ltd on behalf of British Ecological Society.Estimating animal abundance has a key role to play in ecology and conservation, but survey methods are always challenged by imperfect detection. Among the techniques applied to deal with this issue, Double Observer (DO) is increasing in popularity due to its cost‐effectiveness. However, the effort of using DO for surveying large territories can be significant. A DO‐based survey method that allows accurate abundance estimations with reduced effort would increase the applicability of the method. This would have positive effects on the conservation of species which are challenging to survey such as mountain ungulates. We used computer simulations based on real data and a field test to assess the reliability of the DO and of a new proposed survey procedure, the Double Observer Adjusted Survey (DOAS). DOAS is based on total block counts adjusted with some DO surveys conducted in a proportion of the total area only. Such DO surveys are then used to estimate detection probability with a mark‐recapture‐derived approach. We found that full DO is much more accurate than simple block counts for abundance estimations. DOAS is a less demanding alternative to full DO and can produce comparable abundance estimates, at the cost of a slightly lower precision. However, in the DOAS overall detectability has to be estimated within a sufficient number of sites (around a quarter of the total) to obtain a higher precision and avoid large overestimations. Practical implications. DO methods could increase the reliability of abundance estimations in mountain ungulates and other gregarious species. Full DO in particular could allow researchers to obtain unbiased estimations with high precision and its usage is therefore suggested instead of block counts in wildlife monitoring. Given the high costs of full DO, the DOAS procedure could be a viable and cost‐effective survey strategy to improve abundance estimates when resources are scarce.MP was financially supported by a Sustainable Futures studentship by the University of Chester sponsored with a matched funding by the Gran Paradiso National Park (grant reference: BIO20/10)
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
From Field to Model: Monitoring Methods and Integrated Population Modelling of Alpine ibex (Capra ibex)
No full textClimate change poses numerous threats to wildlife inhabiting mountain environments, where changes are occurring rapidly. Mountain ungulates, which play a key role in alpine ecosystems, are especially vulnerable. Many are already in an unfavourable conservation status, and their conservation is further challenged by limitations in biodemography studies and monitoring efforts. Monitoring is indeed complicated by imperfect detection (the inability to count all individuals) and by the costs and difficulties of working in rugged mountain habitats. This thesis aims to address some of these limitations and strengthen conservation strategies for mountain ungulates. Since monitoring forms the foundation of effective management, but traditional count methods (block counts) are often imprecise, I explore alternative approaches to improve reliability while reducing costs. I then focus on another key objective: understanding the drivers of population dynamics in ungulates and the effects of a changing environment on their biodemography. To achieve these objectives, I focus on the Alpine ibex (Capra ibex L., 1758) population in Gran Paradiso National Park (GPNP, Northwestern Italian Alps), which offers an exceptionally long time series of counts and individual survival data. Using simulations based on real-case parameters, I test the reliability of sample counts (counting only a portion of the total area) as a low-effort monitoring approach. Results show that surveying half of the target area is sufficient to detect relevant population trends, demonstrating how sample counts could be valuable for population monitoring. I also propose a new census framework, the Double Observer Adjusted Survey (DOAS), which improves count reliability with minimal additional effort. This method uses Double Observer repeats to estimate detectability and adjust data from full-area block counts. Both simulations and a field test confirm its reliability, indicating its suitability for cost-effective and accurate abundance estimation. Furthermore, I analyse detectability and its determinants in the study population, showing that individuals are more easily observed under certain weather conditions or terrain topography. Accounting for these factors could improve traditional block counts without replacing them. Finally, I use Integrated Population Models to reconstruct the population dynamics of the study population over the last 70 years. These analyses suggest that climate change can strongly influence ungulate dynamics and age structure through alterations in snow cover, temperature, and vegetation, and that juveniles could be the most sensitive age class and shape population trajectories. The effects of climate change could be contrasting: in GPNP, adults are showing higher survival due to milder winters, whereas kid survival fall as a consequence of population aging, leading to an overall abundance reduction. Together, these findings could improve conservation efforts for Alpine ibex and other mountain ungulates, providing practical tools for monitoring populations and understanding the ecological and environmental drivers that shape them.Thesis deposited following repository upgrade (2nd to 23rd February 2026). Exam board date: 18th March 2026
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