While the Mediterranean Sea has been designated as a Global Biodiversity Hotspot, assessments of cetacean population abundance are lacking for large portions of the region, particularly in the ...southern and eastern basins. The challenges and costs of obtaining the necessary data often result in absent or poor abundance information. We applied capture-recapture models to estimate abundance, survival and temporary emigration of odontocete populations within a 2,400 km2 semi-enclosed Mediterranean bay, the Gulf of Corinth. Boat surveys were conducted in 2011-2015 to collect photo-identification data on striped dolphins Stenella coeruleoalba, short-beaked common dolphins Delphinus delphis (always found together with striped dolphins in mixed groups) and common bottlenose dolphins Tursiops truncatus, totaling 1,873 h of tracking. After grading images for quality and marking distinctiveness, 23,995 high-quality photos were included in a striped and common dolphin catalog, and 2,472 in a bottlenose dolphin catalog. The proportions of striped and common dolphins were calculated from the photographic sample and used to scale capture-recapture estimates. Best-fitting robust design capture-recapture models denoted no temporary emigration between years for striped and common dolphins, and random temporary emigration for bottlenose dolphins, suggesting different residency patterns in agreement with previous studies. Average estimated abundance over the five years was 1,331 (95% CI 1,122-1,578) striped dolphins, 22 (16-32) common dolphins, 55 (36-84) "intermediate" animals (potential striped x common dolphin hybrids) and 38 (32-46) bottlenose dolphins. Apparent survival was constant for striped, common and intermediate dolphins (0.94, 95% CI 0.92-0.96) and year-dependent for bottlenose dolphins (an average of 0.85, 95% CI 0.76-0.95). Our work underlines the importance of long-term monitoring to contribute reliable baseline information that can help assess the conservation status of wildlife populations.
Demographic data of rare and endangered species are often too sparse to estimate vital rates and population size with sufficient precision for understanding population growth and decline. Yet, the ...combination of different sources of demographic data into one statistical model holds promise. We applied Bayesian integrated population modeling to demographic data from a colony of the endangered greater horseshoe bats (Rhinolophus ferrumequinum). Available data were the number of subadults and adults emerging from the colony roost at dusk, the number of newborns from 1991 to 2005, and recapture data of subadults and adults from 2004 and 2005. Survival rates did not differ between sexes, and demographic rates remained constant across time. The greater horseshoe bat is a long-lived species with high survival rates (first year: 0.49 SD 0.06; adults: 0.91 SD 0.02) and lowfecundity (0.74 SD 0.12). The yearly average population growth was 4.4% (SD 0.1%) and there were 92 (SD 10) adults in the colony in year 2005. Had we analyzed each data set separately, we would not have been able to estimate fecundity, the estimates of survival would have been less precise, and the estimate of population growth biased. Our results demonstrate that integrated models are suitable for obtaining crucial demographic information from limited data.
Optimizing the effect of management practices on weed population dynamics is challenging due to the difficulties in inferring demographic parameters in seed banks and their response to disturbance. ...Here, we used a long‐term plant survey between 2006 and 2012 in 46 French vineyards and quantified the effects of management practices (tillage, mowing, and herbicide) on colonization, germination, and seed survival of 30 weed species in relation to their seed mass. To do so, we used a recent statistical approach to reliably estimate demographic parameters for plant populations with a seed bank using time series of presence–absence data, which we extended to account for interspecies variation in the effects of management practices on demographic parameters. Our main finding was that when the level of disturbance increased (i.e., in plots with a higher number of herbicides, tillage, or mowing treatments), colonization success and survival in large‐seeded species increased faster than in small‐seeded species. High disturbance through tillage increased survival in the seed bank of species with high seed mass. The application of herbicides increased germination, survival, and colonization probabilities of species with high seed mass. Mowing, representing habitats more competitive for light, increased the survival of species with high seed mass. Overall, the strong relationships between the effects of management practices and seed mass provide an indicator for predicting the dynamics of weed communities under disturbance.
This is one of the very few studies determining the effect of management practices on seed bank dynamics in weed species, and notably the first one ever in vineyards. We used a long‐term plant survey between 2006 and 2012 in 46 vineyard plots in France (Champagne, Beaujolais, and Languedoc wine‐growing areas) with 883 flora surveys to test whether interspecific variation in the effects of management practices (tillage, mowing, and herbicide use) on demographic parameters could be explained by seed mass. We used a hidden Markov model (HMM) recently developed to estimate colonization, germination, and seed bank survival using presence–absence observations which we extended with a multilevel model in a Bayesian framework. The strong relationships between the intensity of the management effects and seed mass provide a reliable indicator for predicting the dynamics of weed communities.
Population monitoring traditionally relies on population counts, accounting or not for the issue of detectability. However, this approach does not permit to go into details on demographic processes. ...Therefore, Capture-Recapture (CR) surveys have become popular tools for scientists and practitioners willing to measure survival response to environmental change or conservation actions. However, CR surveys are expensive and their design is often driven by the available resources, without estimation about the level of precision they provide for detecting changes in survival, despite optimising resource allocation in wildlife monitoring is increasingly important. Investigating how CR surveys could be optimised by manipulating resource allocation among different design components is therefore critically needed. We have conducted a simulation experiment exploring the statistical power of a wide range of CR survey designs to detect changes in the survival rate of birds. CR surveys differ in terms of number of breeding pairs monitored, number of offspring and adults marked, resighting effort and survey duration. We compared open-nest (ON) and nest-box (NB) monitoring types, using medium- and long-lived model species. Increasing survey duration and number of pairs monitored increased statistical power. Long survey duration can provide accurate estimations for long-lived birds even for small population size (15 pairs). A cost-benefit analysis revealed that for long-lived ON species, ringing as many chicks as possible appears as the most effective survey component, unless a technique for capturing breeding birds at low cost is available to compensate for reduced local recruitment. For medium-lived NB species, focusing the NB rounds at a period that maximises the chance to capture breeding females inside nest-boxes is more rewarding than ringing all chicks. We show that integrating economic costs is crucial when designing CR surveys and discuss ways to improve efficiency by reducing duration to a time scale compatible with management and conservation issues.
Human dimension is an important component of large carnivore management and conservation. Here, we focus on the human-wildlife conflict related to depredation of livestock by Pyrenean brown bears ...(Ursus arctos), despite the population being among the smallest in the world. Two reintroductions were performed in the past to ensure the survival of the population, yet its conservation status remains critical due to small size, heavy inbreeding and disagreements over its management. We investigated the often-neglected spatial variations in attitude towards predator presence to improve our understanding of the human dimensions surrounding this conflict. We used a questionnaire to assess the drivers explaining the attitude of the local human population (n=577) of the Pyrenees towards bear presence. Our results show that spatial variables (place of birth and county of residence of the respondent) are strong predictors of attitude. The residents of two counties in particular (Haute-Garonne and Pyrénées-Atlantiques) displayed a positive attitude, while the residents of the Hautes-Pyrénées county had the most negative attitude. People born outside of the Pyrenees also showed a more positive inclination towards bear presence than people born and raised in France's southwestern mountain range. Both these results may imply a link between the history of local communities with predator presence and their current attitude. Accounting for small-scale spatial heterogeneity in social–ecological studies of human-wildlife conflicts will prove useful to get a more accurate mapping of attitudes and inform subsequent management decisions.
•It is the first quantitative analysis of attitudes towards bears in France.•Significant variations in attitude were observed from one county to another.•The birthplace of the respondents affected their attitude towards bears.•Small-scale spatial variables can influence attitudes towards large predators.
The modern anthropized landscape is a major source of hazards for large animals such as raptors. Collisions with cables, vehicles and trains, as well as electrocution cause casualties, which may ...negatively impact populations. Yet, demographic studies of that impact remain scarce, which is an impediment to evidence-based conservation action. We studied the dynamics of an eagle owl (
Bubo bubo) population in the northwestern Alps (Switzerland). We estimated, firstly, its demographic parameters using a Bayesian integrated population model; secondly, the frequency of different types of casualty through radio-tracking. Thirdly, we investigated the effects of reductions of human-related mortality on population trends. The breeding population was small but remained fairly stable during 20
years, suggesting that it was apparently in a good shape. However, survival probabilities of all age classes were very low (⩽0.61), productivity fairly good (0.93), and immigration very high (1.6 females per pair and year), indicating that the population operated as a sink. Half of the mortality was caused by infrastructure, with electrocution accounting for 24% of all fatalities. The elimination of electrocution would result in a strong population increase (17% annually). Under that scenario, immigration rate could decline by 60% and the population would still remain stable. Given that the supply of recruits from elsewhere is likely to continue, we can expect a rapid local population recovery if dangerous electric pylons are mitigated systematically. Our study demonstrates that detailed demographic analyses are necessary to diagnose problems occurring in populations and to identify efficient conservation actions.
In an era of increasing human pressure on nature, understanding the spatiotemporal patterns of wildlife relative to human disturbance can inform conservation efforts, especially for large carnivores. ...We examined the temporal activity and spatial patterns of wolves and eight sympatric mammals at 71 camera trap stations in Greece. Grey wolves temporally overlapped the most with wild boars (Δ = 0.84) and medium-sized mammals (Δ > 0.75), moderately with brown bears (Δ = 0.70), and least with roe deer (Δ = 0.46). All wild mammals were mainly nocturnal and exhibited low temporal overlap with human disturbance (humans, vehicles, livestock, and dogs; Δ = 0.18–0.36), apart from roe deer, which were more diurnal (Δ = 0.80). Six out of nine species increased their nocturnality at sites of high human disturbance, particularly roe deer and wolves. The detection of wolves was negatively associated with paved roads, the detection of roe deer was negatively associated with human disturbance, and the detection of wild boars was negatively associated with dogs. The detection of bears, boars, and foxes increased closer to settlements. Our study has applied implications for wolf conservation and human–wildlife coexistence.
Emotions are short, intuitive mental processes that are important components of people's cognitions. They can influence attitudes (i.e. positive or negative evaluations of objects), and they are ...involved in decision‐making processes. In the context of human‐wildlife coexistence, mostly emotional dispositions have been studied (i.e. people's decontextualized, stable tendencies to react in a certain way towards wildlife), in contrast to emotional states (i.e. quick reactions elicited in specific contexts), which have been overlooked. This limits our understanding of emotional states and the role of emotional diversity in shaping attitudes towards wildlife species.
Here, we quantified emotional states elicited by context‐specific wolf encounters featured in a set of YouTube videos. We conducted a social survey in rural populations of 24 randomly selected cities in France (n = 795) to (i) quantify emotional diversity and (ii) test the relationship between emotional states and attitudes towards wolves, accounting for individual and regional factors.
We found that emotional states that were most expressed across the six contexts of encounter were surprise, interest and fear, in this order. Emotional diversity was highly context‐specific, with significantly different emotional identity, dispersion and extremization across the six contexts of encounters. Most variance in attitudes was explained by emotional factors alone (28%) and the best model including all three groups of predictors (emotional, individual and regional factors) explained 57% of the variance. The strongest effects of emotional states on attitudes were those of anger and joy. Fear had only half the effect of joy on attitudes.
Synthesis and applications: Our results highlight the importance and context‐specificity of emotional diversity for human‐carnivore coexistence. Complementary to previous studies focusing on single emotions and on decontextualized emotional dispositions, quantifying diverse, context‐dependent emotional states can be helpful to improve decision‐making in three different ways: (i) address relevant contexts triggering anger, which is a feeling rooted in perceived injustice, (ii) reduce emotional biases involving fear of carnivores given the extremely low probability of risks to human life and (iii) promote positive emotions like joy to better reflect costs and benefits of sharing landscapes with large carnivores.
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Résumé
Les émotions sont des processus mentaux courts et intuitifs qui constituent des éléments importants de la cognition humaine. Elles peuvent influencer les attitudes (c’est‐à‐dire les évaluations positives ou négatives d’objets) et sont impliquées dans les processus décisionnels. Dans le contexte de la cohabitation homme‐faune, ce sont principalement les dispositions émotionnelles qui ont été étudiées (les tendances stables et décontextualisées des personnes à réagir d'une certaine manière envers la faune), contrairement aux états émotionnels (les réactions rapides suscitées dans des contextes spécifiques). Cela limite notre compréhension des états émotionnels et du rôle de la diversité émotionnelle dans la formation des attitudes envers les espèces de la faune sauvage.
Dans cette étude, nous avons quantifié les états émotionnels suscités par des interactions avec des loups contenues dans des vidéos YouTube. Nous avons mené une enquête sociale auprès de populations rurales de 24 villes sélectionnées au hasard en France (n = 795) afin de (i) quantifier la diversité émotionnelle et (ii) tester la relation entre les états émotionnels et les attitudes envers les loups, en tenant compte de facteurs individuels et régionaux.
Nous avons constaté que les états émotionnels les plus exprimés à travers les six contextes de rencontre étaient la surprise, l'intérêt et la peur, dans cet ordre. La diversité émotionnelle était fortement dépendante du contexte, avec une identité émotionnelle, une dispersion et une extrémisation significativement différentes à travers les six contextes d’interactions. La majeure partie de la variance dans les attitudes était expliquée par les facteurs émotionnels (28%), et le meilleur modèle incluant les trois groupes de prédicteurs (émotionnels, individuels et régionaux) expliquait 57% de la variance des attitudes. Les effets les plus importants des états émotionnels sur les attitudes étaient ceux de la colère et de la joie. La peur n’avait que la moitié de l’effet de la joie sur les attitudes.
Synthèse et applications: Nos résultats mettent en évidence l’importance et la spécificité contextuelle de la diversité émotionnelle pour la cohabitation entre les humains et les carnivores. En complément des études précédentes axées sur une seule émotion, ou sur des dispositions émotionnelles décontextualisées, la quantification de la diversité des états émotionnels selon différents contextes peut contribuer à améliorer la prise de décision de trois manières différentes : (i) s’occuper des situations qui engendrent de la colère, qui est un sentiment associé à une injustice perçue, (ii) réduire les biais émotionnels liés à la peur des carnivores étant donné la probabilité extrêmement faible de risques pour la vie humaine, et (iii) promouvoir des émotions positives comme la joie pour mieux refléter les coûts, mais aussi les bénéfices associés à la présence de ces grands carnivores dans nos paysages.
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The canalization hypothesis postulates that the rate at which trait variation generates variation in the average individual fitness in a population determines how buffered traits are against ...environmental and genetic factors. The ranking of a species on the slow-fast continuum - the covariation among life-history traits describing species-specific life cycles along a gradient going from a long life, slow maturity, and low annual reproductive output to a short life, fast maturity, and high annual reproductive output - strongly correlates with the relative fitness impact of a given amount of variation in adult survival. Under the canalization hypothesis, longlived species are thus expected to display less individual heterogeneity in survival at the onset of adulthood, when reproductive values peak, than short-lived species. We tested this life-history prediction by analysing long-term time series of individual-based data in nine species of birds and mammals using capture-recapture models. We found that individual heterogeneity in survival was higher in species with short-generation time (< 3 years) than in species with long generation time (> 4 years). Our findings provide the first piece of empirical evidence for the canalization hypothesis at the individual level from the wild.
The concept of Darwinian fitness is central in evolutionary ecology, and its estimation has motivated the development of several approaches. However, measuring individual fitness remains challenging ...in empirical case studies in the wild. Measuring fitness requires a continuous monitoring of individuals from birth to death, which is very difficult to get in part because individuals may or may not be controlled at each reproductive event and recovered at death. Imperfect detection hampers keeping track of mortality and reproductive events over the whole lifetime of individuals. We propose a new statistical approach to estimate individual fitness while accounting for imperfect detection. Based on hidden process modelling of longitudinal data on marked animals, we show that standard metrics to quantify fitness, namely lifetime reproductive success, individual growth rate and lifetime individual contribution to population growth, can be extended to cope with imperfect detection inherent to most monitoring programs in the wild. We illustrate our approach using data collected on individual roe deer in an intensively monitored population.
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