Aim In several ecosystems, the diversity of functional species traits has been shown to have a stronger effect on ecosystem functioning than taxonomic diversity alone. However, few studies have explored this idea at a large geographical scale. In a multisite experiment, we unravelled the relationship between ecosystem function and functional completeness of species assemblages using dung beetles as a model group, focusing on dung removal and secondary seed dispersal. Location Seventeen grassland locations across the Western Palaearctic. Methods We used a randomized block design with different exclosure types to control the dung and seed removing activities of individual functional groups of the local dung beetle assemblage. We classified dung beetle species according to resource specialization and into functional groups based on dung processing behaviour (dwellers, tunnellers, rollers) and body size (small, large). Additionally, we assessed the role of other soil macro‐invertebrates. By sampling the dung beetle community and measuring the remaining dung and seeds after the experiment, the impact of each functional group was estimated. Results Dung beetle assemblages differed along a north–south and east–west gradient. Dwellers dominated northernmost sites, whereas at lower latitudes we observed more tunnellers and rollers indicating a functional shift. Resource specialists were more abundant in southern and eastern areas. Overall, functional group diversity enhanced dung removal. More dung (+46.9%) and seeds (+32.1%) were removed in the southern sites and tunnellers and rollers were more effective. At the northernmost sites, where tunnellers were scarce or absent, other soil macro‐invertebrates removed the majority of dung. Main conclusions The conservation of functionally complete dung beetle assemblages is crucial to maintain the ecosystem functions provided by dung beetles. Given the latitudinal variation in functional group diversity, it is reasonable to expect compositional changes due to climate change. These changes could lead to increased dung removal and a higher secondary seed dispersal rate in northern regions.

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In a mosaic landscape in N-Belgium (W-Europe), consisting of forest, grassland, and wooded pasture on former agricultural land, we assessed nitrogen redistribution by free-ranging cattle (±0.2 animal units ha −1 yr −1 ). We examined if the spatial redistribution of nitrogen among habitats by cattle could restore nutrient-poor conditions in preferred foraging habitats, and conversely whether such translocation could lead to extreme eutrophication in preferred resting habitats. We used nitrogen content of different diet classes, habitat use, foraging and defecation behavior, weight gain, and nitrogen losses in the actual situation to explore four different habitat proportion scenarios and two different foraging strategies to calculate a net nitrogen balance per habitat. An atmospheric deposition of 30 kg N ha −1 yr −1 with varying interception factors according to the habitat types was included in an integrated nitrogen balance. All scenarios showed a net nitrogen transport from grassland and wooded pasture to forest habitat. We found that nitrogen redistribution strongly depends on habitat proportion. Nitrogen losses from preferred grassland habitat can be high, given its proportion is small. Depletion is only to be expected at excretion-free areas and probably is of minor importance to trigger the establishment of woody species. In general, nitrogen transported by cattle was much lower than input by atmospheric deposition, but grazing can compensate for high N inputs in excretion-free areas and maintain grassland types that support critical loads of 20-25 kg N ha −1 yr −1 . In none of the scenarios, N transport by cattle resulted in the exceeding of critical nitrogen loads to vulnerable forest ground vegetation.

Camera traps placed in the field, photograph warm-bodied animals that pass in front of an infrared sensor. The imagery represents a rich source of data on mammals larger than ~200 grams, providing information at the level of species and communities. Camera-trap surveys generate observations of specific mammals at a certain location and time, including photo evidence that can be evaluated by experts to map species distribution patterns. The imagery also provides information on the species composition of local communities, identifying which species co-occur and in what proportion. Moreover, the images contain information on activity patterns and other interesting aspects of animal behaviour. Because surveys can be standardized relatively easily, camera traps are well suited for documenting shifts in the behaviour, distribution and community composition, for example in response to climate and land-use change. Imagery from camera traps can thus serve as a baseline for subsequent surveys. In less than two decades, camera traps have become the standard tool for surveying mammals. They are simple to use and non-invasive, requiring no special permits. As a consequence they are widely used by professionals and hobbyists alike. Together, tens of thousands of users have the potential to form a huge sensor network. Unfortunately however, imagery and data collected are currently rarely integrated. Rather, they are lost at a massive scale. Users tend to retain only a subset of the photos and discard the rest. Or the material ends up on an external hard disk that will at some point fail or be erased as these scientific data tend to be used within the scope of specific projects. Very few of the wealth of material becomes available for scientific research and monitoring. Moreover, joint projects are rare and there is little coordination between camera-trap users. A solution to this problem is provided by Agouti, a platform for the organization, processing and storage of camera-trap imagery (www.agouti.eu). The aim of Agouti is, on the one hand, to standardize and facilitate collaborative camera-trap surveys, and on the other hand to compile and secure imagery and data for scientific research and monitoring, by encouraging users to share their material. Agouti provides an interface that allows users to collaborate on projects, organize and manage their surveys, upload and store imagery, and annotate images with species identifications and characteristics. Images can also be annotated through basic image recognition and crowd sourcing via a connection with the citizen science platform Zooniverse, which creates the potential to reach new audiences. Exporting data and imagery in the Camera Trap Metadata Standard (Forrester et al. 2016) will be supported in the near future. This will allow data to be archived outside of Agouti in research repositories such as Zenodo and by further mapping to Darwin Core to be made discoverable on the Global Biodiversity Information Facility (GBIF). Agouti provides both professionals and the public with a practical solution for retaining camera-trap surveys and simultaneously engages people in contributing data to science in a standardized and organized manner, to the benefit of science and conservation.