Fruit abundance and trait matching determine diet type and body condition across frugivorous bird populations

Research on seed‐dispersal mutualisms has been highly unbalanced towards the plants, largely overlooking the fitness effects of fruit resources on frugivorous animals. Moreover, despite morphological mismatches like gape limitation may reduce the abundance of fruits that are actually accessible to a frugivore species, there is very little evidence on the trait‐matching implications from a frugivore's perspective. Here, we refine recent resource‐provisioning models to comprehensively test the joint effects of fruit abundance and trait matching on diet type and body condition (a surrogate of fitness) across frugivorous bird populations: Sardinian warblers Curruca melanocephala inhabiting ten Mediterranean forests differing in the abundance and composition of fleshy fruits. We hypothesised the abundance of fruit resources to have positive effects on the degree of frugivory and body condition of warblers, and such effects to be more pronounced when accounting for both trait matching (accessible fruits) and resource provisioning (energy in accessible fruits). We found a sharp threshold over which warblers shifted from a diet with very little or even no fruits to a predominantly frugivorous diet with increasing the local abundance of accessible fruits. We also found a strong positive relationship between the abundance of accessible fruits and the body condition of warblers (body mass and residual body mass), an effect that was more pronounced in females than in males. Although diet type and body condition were much better predicted when accounting for trait matching, accounting for resource provisioning did not improve the explanatory power of fruit resources. The fact that we detected strong and sex‐dependent effects of fruit resources on body condition just a few weeks before the breeding season suggests that fruit resources likely affect the timing and success of reproduction, a question that deserves further research. Our findings provide new insight into the fitness consequences of seed‐dispersal mutualisms for frugivorous animals.info:eu-repo/semantics/acceptedVersio

Unravelling seed dispersal through fragmented landscapes: Frugivore species operate unevenly as mobile links

Seed dispersal constitutes a pivotal process in an increasingly fragmented world, promoting population connectivity, colonization and range shifts in plants. Unveiling how multiple frugivore species disperse seeds through fragmented landscapes, operating as mobile links, has remained elusive owing to methodological constraints for monitoring seed dispersal events. We combine for the first time DNA barcoding and DNA microsatellites to identify, respectively, the frugivore species and the source trees of animal-dispersed seeds in forest and matrix of a fragmented landscape. We found a high functional complementarity among frugivores in terms of seed deposition at different habitats (forest vs. matrix), perches (isolated trees vs. electricity pylons) and matrix sectors (close vs. far from the forest edge), cross-habitat seed fluxes, dispersal distances and canopy-cover dependency. Seed rain at the landscape-scale, from forest to distant matrix sectors, was characterized by turnovers in the contribution of frugivores and source-tree habitats: open-habitat frugivores replaced forest-dependent frugivores, whereas matrix trees replaced forest trees. As a result of such turnovers, the magnitude of seed rain was evenly distributed between habitats and landscape sectors. We thus uncover key mechanisms behind "biodiversity-ecosystem function" relationships, in this case, the relationship between frugivore diversity and landscape-scale seed dispersal. Our results reveal the importance of open-habitat frugivores, isolated fruiting trees and anthropogenic perching sites (infrastructures) in generating seed dispersal events far from the remnant forest, highlighting their potential to drive regeneration dynamics through the matrix. This study helps to broaden the "mobile-link" concept in seed dispersal studies by providing a comprehensive and integrative view of the way in which multiple frugivore species disseminate seeds through real-world landscapes.This study was funded by grants (to P.J.) of the Spanish MINECO (CGL2013-47429P) and Junta de Andalucía Excellence Projects (RNM-5731), and 632 supported by a Severo Ochoa Award for Centres of Excellence in R+D+I (SEV-2012-0262). While writing this paper, J.P.G.V. was funded by an Individual Fellowship from the Marie 634 Sklodowska-Curie Actions (H2020-MSCA- IF-2014-656572: MobileLinks). C.C. received scholarships from the National Counsel of Technological and Scientific Development (CNPq, 636 401258/2012-2) and the São Paulo Research Foundation (FAPESP, 2014/01029-5)

Moving from frugivory to seed dispersal: incorporating the functional outcomes of interactions in plant-frugivore networks

1. There is growing interest in understanding the functional outcomes of species interactions in ecological networks. For many mutualistic networks, including pollination and seed dispersal networks, interactions are generally sampled by recording animal foraging visits to plants. However, these visits may not reflect actual pollination or seed dispersal events, despite these typically being the ecological processes of interest. 2. Frugivorous animals can act as seed dispersers, by swallowing entire fruits and dispersing their seeds, or as pulp peckers or seed predators, by pecking fruits to consume pieces of pulp or seeds. These processes have opposing consequences for plant reproductive success. Therefore, equating visitation with seed dispersal could lead to biased inferences about the ecology, evolution and conservation of seed dispersal mutualisms. 3. Here we use natural history information on the functional outcomes of pairwise bird-plant interactions to examine changes in the structure of seven European plant-frugivore visitation networks after non-mutualistic interactions (pulp-pecking and seed predation) have been removed. Following existing knowledge of the contrasting structures of mutualistic and antagonistic networks, we hypothesised a number of changes following interaction removal, such as increased nestedness and lower specialisation. 4. Non-mutualistic interactions with pulp peckers and seed predators occurred in all seven networks, accounting for 21–48% of all interactions and 6–24% of total interaction frequency. When non-mutualistic interactions were removed, there were significant increases in network-level metrics such as connectance and nestedness, while robustness decreased. These changes were generally small, homogenous and driven by decreases in network size. Conversely, changes in species-level metrics were more variable and sometimes large, with significant decreases in plant degree, interaction frequency, specialisation and resilience to animal extinctions, and significant increases in frugivore species strength. 5. Visitation data can overestimate the actual frequency of seed dispersal services in plant-frugivore networks. We show here that incorporating natural history information on the functions of species interactions can bring us closer to understanding the processes and functions operating in ecological communities. Our categorical approach lays the foundation for future work quantifying functional interaction outcomes along a mutualism–antagonism continuum, as documented in other frugivore faunas.B.I.S. was supported by the Natural Environment Research Council as part of the Cambridge Earth System Science NERC DTP (NE/L002507/1). J.P.G.‐V. was funded by an Individual Fellowship from the Marie Sklodowska‐Curie Actions (H2020‐MSCA‐IF‐2014‐656572: MobileLinks). D.G. was funded by a grant from the Spanish MinECo (CGL2017‐82847‐P). W.J.S. is funded by Arcadia. N.F. thanks the administration of the Białowieża National Park, the forestry administrations of Białowieża, Hajnówka and Browsk and Polish authorities (Ministry of Environment, GDOS and RDOS) for the permissions to work in Białowieża Forest. J.A. was supported by the German Federal Foundation for Environment (DBU) and by the German Academic Exchange Service in the framework of a post‐doctorate fellowship grant (DAAD, No 91568794). L.V.D. was supported by the Natural Environment Research Council (grants NE/K015419/1 and NE/N014472/1)

Status and trends of European pollinators. Key findings of the STEP project

Peer reviewe

Trabecular bone score in active or former smokers with and without COPD

Background Smoking is a recognized risk factor for osteoporosis. Trabecular bone score (TBS) is a novel texture parameter to evaluate bone microarchitecture. TBS and their main determinants are unknown in active and former smokers. Objective To assess TBS in a population of active or former smokers with and without Chronic Obstructive Pulmonary Disease (COPD) and to determine its predictive factors. Methods Active and former smokers from a pulmonary clinic were invited to participate. Clinical features were recorded and bone turnover markers (BTMs) measured. Lung function, low dose chest Computed Tomography scans (LDCT), dual energy absorptiometry (DXA) scans were performed and TBS measured. Logistic regression analysis explored the relationship between measured parameters and TBS. Results One hundred and forty five patients were included in the analysis, 97 (67.8%) with COPD. TBS was lower in COPD patients (median 1.323; IQR: 0.13 vs 1.48; IQR: 0.16, p = 0.003). Regression analysis showed that a higher body mass index (BMI), younger age, less number of exacerbations and a higher forced expiratory volume-one second (FEV1%) was associated with better TBS (β = 0.005, 95% CI:0.000–0.011, p = 0.032; β = -0.003, 95% CI:-0.007(-)-0.000, p = 0.008; β = -0.019, 95% CI:-0.034(-)-0.004, p = 0.015; β = 0.001, 95% CI:0.000–0.002, p = 0.012 respectively). The same factors with similar results were found in COPD patients. Conclusions A significant proportion of active and former smokers with and without COPD have an affected TBS. BMI, age, number of exacerbations and the degree of airway obstruction predicts TBS values in smokers with and without COPD. This important information should be considered when evaluating smokers at risk of osteoporosis

Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator-dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes

The major barriers to evidence-informed conservation policy and possible solutions.

Conservation policy decisions can suffer from a lack of evidence, hindering effective decision-making. In nature conservation, studies investigating why policy is often not evidence-informed have tended to focus on Western democracies, with relatively small samples. To understand global variation and challenges better, we established a global survey aimed at identifying top barriers and solutions to the use of conservation science in policy. This obtained the views of 758 people in policy, practice, and research positions from 68 countries across six languages. Here we show that, contrary to popular belief, there is agreement between groups about how to incorporate conservation science into policy, and there is thus room for optimism. Barriers related to the low priority of conservation were considered to be important, while mainstreaming conservation was proposed as a key solution. Therefore, priorities should focus on convincing the public of the importance of conservation as an issue, which will then influence policy-makers to adopt pro-environmental long-term policies

Physical activity and risk of Metabolic Syndrome in an urban Mexican cohort

Abstract Background In the Mexican population metabolic syndrome (MS) is highly prevalent. It is well documented that regular physical activity (PA) prevents coronary diseases, type 2 diabetes and MS. Most studies of PA have focused on moderate-vigorous leisure-time activity, because it involves higher energy expenditures, increase physical fitness, and decrease the risk of MS. However, for most people it is difficult to get a significant amount of PA from only moderately-vigorous leisure activity, so workplace activity may be an option for working populations, because, although may not be as vigorous in terms of cardio-respiratory efforts, it comprises a considerable proportion of the total daily activity with important energy expenditure. Since studies have also documented that different types and intensity of daily PA, including low-intensity, seem to confer important health benefits such as prevent MS, we sought to assess the impact of different amounts of leisure-time and workplace activities, including low-intensity level on MS prevention, in a sample of urban Mexican adults. Methods The study population consisted of 5118 employees and their relatives, aged 20 to 70 years, who were enrolled in the baseline evaluation of a cohort study. MS was assessed according to the criteria of the National Cholesterol Education Program, ATP III and physical activity with a validated self-administered questionnaire. Associations between physical activity and MS risk were assessed with multivariate logistic regression models. Results The prevalence of the components of MS in the study population were: high glucose levels 14.2%, high triglycerides 40.9%, high blood pressure 20.4%, greater than healthful waist circumference 43.2% and low-high density lipoprotein 76.9%. The prevalence of MS was 24.4%; 25.3% in men and 21.8% in women. MS risk was reduced among men (OR 0.72; 95%CI 0.57–0.95) and women (OR 0.78; 95%CI 0.64–0.94) who reported an amount of ≥30 minutes/day of leisure-time activity, and among women who reported an amount of ≥3 hours/day of workplace activity (OR 0.75; 95%CI 0.59–0.96). Conclusion Our results indicate that both leisure-time and workplace activity at different intensity levels, including low-intensity significantly reduce the risk of MS. This finding highlights the need for more recommendations regarding the specific amount and intensity of leisure-time and workplace activity needed to prevent MS