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Urbanization transforms natural ecosystems, creating an environmental mosaic, characterized by native vegetation sites mixed with constructed sites. In this study, we compared dung beetle taxonomic and functional diversity between residential and greenspace sites (remnants of native vegetation) in an urban landscape in the Brazilian Cerrado. We sampled dung beetles in February (2013–2014 – 2015) in four sites of remnants of native Cerado (here called “greenspace”) and four residential sites in the city of Aquidauana, Mato Grosso do Sul, Brazil. Greenspace sites are characterized by a mixture of plants of two distinct strata (phytophysiognomy Cerrado sensu stricto), a woody layer of trees and large shrubs, while residential sites are characterized by residential buildings (housing and commercial sites), unpaved roads with tree-lined streets. Dung beetle abundance and species richness were higher in greenspace sites. Species composition differed significantly among habitats but functional composition did not differ. Functional dispersion and functional richness was higher in greenspace sites. On the other hand, functional evenness was similar between greenspace and residential sites. In this study, we found higher taxonomic and functional components of dung beetle diversity in greenspace when compared to residential sites in the Brazilian Cerrado. Thus, we highlight the importance greenspace sites for the conservation of dung beetle biodiversity and consequently their ecological services (i.e. such as soil aeration, secondary seed dispersal, parasite regulation), which indirectly can affect human life quality in the urban matrix.

Novel and hybrid ecosystems present different conservation values for native species. Therefore, the classification of modified ecosystems into a novel or hybrid state is an essential step to assist conservation strategies for biodiversity. During the last decades, plantations of Eucalyptus have increased in the highly threatened Atlantic Forest region, highlighting the importance of defining this ecosystem as novel or hybrid. In this study, we evaluated whether Eucalyptus plantations are novel or hybrid ecosystems by contrasting biotic components (dung beetle communities) and abiotic components (local environmental variables) within historical (Atlantic Forest remnants) and non-historical (pasture) environments in the Atlantic Forest biome, located in Bahia state, Brazil. Our results show that Eucalyptus plantations should be classified and managed as a hybrid ecosystem in this biome. Of the 21 dung beetle species found in Eucalyptus, ten were shared with historical forests (52.6% of Eucalyptus species) and 6 with pastures (31.5%). Eucalyptus plantations have environmental aspects similar to both historical forests and pastures. Despite presenting similar components to historical and non-historical ecosystems, Eucalyptus plantations are sufficiently distinct not to be classified as either one of them. Our results highlight the potential conservation value of Eucalyptus plantations in the Atlantic Forest region as complementary habitat for historical species, and we discuss how alternative management at landscape and stand (local) scales might increase this value. Although dung beetles are an excellent group to monitor biodiversity, we reinforce the necessity to perform further studies using another taxon that present different ecosystem requirements.

Grazing by large herbivorous mammals is still a structuring force in tropical grassy ecosystems, and cattle grazing is one of the main economic activities carried out in these ecosystems in modern times. Therefore, understanding the impacts of cattle grazing removal on biodiversity may be a key step for conservation of this ecosystem. Here, we studied the successional trajectory of dung beetle communities in a tropical grassy ecosystem after cattle removal. For this, we assessed the patterns of dung beetle taxonomic and functional diversity of 14 natural grasslands with distinct cattle grazing removal ages (from 3 months to 22 years) along a chronosequence, applying the space-for-time substitution method. Our results show a strong decrease in dung beetle abundance (93 times) and species richness (6 times) in the first ten years of cattle removal. However, after ten years there is an increase in dung beetle abundance (73 times) and species richness (5 times). Taxonomic composition was also influenced by cattle removal time demonstrating the importance of cattle in the structuring of dung beetle communities in natural grasslands. In contrast, functional composition and diversity were not affected by cattle grazing removal, indicating these metrics are less sensitive to cattle absence than taxonomic diversity and composition. Our results provide evidence that cattle grazing removal, at least in the short term (10 years), may be an inefficient management tool for restoration and conservation of tropical grassy ecosystems. However, we highlight the need to investigate the reintroduction of cattle grazing after different removal times to provide complimentary information to livestock management able to integrate human use and conservation of tropical grassy ecosystems.

The dung roller beetle Canthon smaragdulus (Scarabaeinae) has a pair of pygidial glands whose secretions have different functions. However, the factors influencing the production of pygidial secretions in these dung beetles are not known. This study is the first to evaluate differences in the amount of pygidial secretions produced by C. smaragdulus individuals in relation to body mass, sex and social status (mature males and females alone or in couple). We also evaluated whether the production of pygidial secretions is stable over time in individual beetles. To achieve this, we collected pygidial secretions from 120 C. smaragdulus individuals and measured their body mass and body size. Secretions were collected twice more, for a total of three samples per specimen, which were obtained every seven days. Our results suggest that alone males produce higher amounts of pygidial secretions than females alone, couple males and couple females. Only the body mass of couple males was positively correlated with the amount of pygidial secretions. This was probably due to couple males remaining in the nest for a few days. Our results confirm that the production of pygidial secretions in dung roller beetles can be influenced by body mass, sex and social status. Thus, further experiments should assess the production of pygidial secretions throughout the dung beetle life cycle under different behavioural contexts such as defence, protection of the nest and reproduction.

Replacing native savannas with exotic pastures not only alters vegetation structure, but it also increases herbivorous cattle dung quantity consequently changing the food resource available for dung beetles. Therefore, this study aims at investigating the relative importance of vegetation structure regarding food resource types to determine dung beetle assemblage in Cerrado savannas and exotic pastures. We carried out a sampling of dung beetles in 30 areas of Cerrado sensu stricto and 30 in areas of exotic pastures across nine municipalities of Minas Gerais state, Brazil, by using pitfall traps baited with cattle dung and human feces. We also characterized these areas according to their herbaceous density, complexity (fractal dimension) and canopy cover. Our study demonstrates that the complete conversion of Cerrado sensu stricto into exotic pasture has a negative effect on dung beetle assemblages. The same dung types differed completely in dung beetle assemblages in native savannas and exotic pasture regarding richness, abundance, species composition and dominance patterns. These findings suggest that environmental filters in exotic pastures, as low cover canopy and herbaceous complexity simplification, probably restrict the establishment of species from Cerrado. We also found different dung beetle communities by comparing pitfall traps baited with cow dung and human feces within the same land use. Thus, alterations in food resources played a secondary role, but were also important. We suggest that increasing herbaceous complexity and canopy cover along with diversifying livestock in exotic pastures could potentially avoid the loss of dung beetles species and their associated ecosystem services.

Tropical forest restoration is becoming increasingly more applied to offset biodiversity loss and maintain ecosystem processes, but knowledge about its efficacy is still limited. We evaluated the success of tropical forest active restoration using dung beetles (Coleoptera: Scarabaeinae) as bioindicators and combining measures of species diversity, composition and functional diversity. We assessed patterns of dung beetles community assembly along a restoration chronosequence and also compared restoration areas with reference (primary and old secondary forest) and degraded (pasture) ecosystems. Species composition in the restoration areas was clearly progressing towards the preserved forests and deviating from the pasture with increasing restoration age. We also found a turnover of open environment specialists and habitat generalists to forest generalists and forest specialist species along the restoration chronosequence. However, the majority of individuals in the older restored habitats were typically forest generalists. Biomass was the only variable that increased with restoration age. Species richness, number of individuals, biomass and functional richness in the restored areas were similar to, or even smaller, than in pastures and substantially lower than forest reference sites. Rarefied richness, functional evenness and functional dispersion did not vary between the habitats. We found that while restored areas have the capacity to host forest-restricted species, 18 years since active restoration has not been long enough to recover a stable and diverse dung beetle assemblage. Our study also demonstrates that measures of composition, species diversity and functional diversity can complement each other and contribute to a better understanding of the efficacy of restoration practices.

There is increasing recognition that community assembly theory can offer valuable insights for ecological restoration. We studied community assembly processes following tropical forest restoration efforts, using dung beetles (Scarabaeinae) as a focal taxon to investigate taxonomic and functional patterns of biodiversity recovery. We evaluated the relative importance of the local environment (i.e., canopy cover, understory cover, tree basal area, and soil texture), landscape context (i.e., habitat patch proximity and availability and percentage of surrounding area classified as natural forest or Eucalyptus spp. plantation), and space (i.e., spatial proximity of the study areas to estimate dispersal limitation or unmeasured spatially structured processes) on dung beetle species and functional trait composition across a gradient of 15 restoration sites in Brazilian Atlantic Forest. We also assessed which factors were the primary determinants in the establishment of individual dung beetle functional groups, classified according to size, food relocation habit, diet, and period of flight activity. Both species and functional trait composition were most strongly influenced by the local environment, indicating that assembly was predominantly driven by niche-based processes. Most of the variation explained by space was co-explained by local environment and landscape context, ruling out a strong influence of dispersal limitation and random colonization on assembly following restoration. In addition, nearly all of the variance explained by landscape context was co-explained by local environment, suggesting that arrival and establishment at a site depends on both local and landscape-scale environmental factors. Despite strong evidence for niche-based assembly, a large amount of variation remained unexplained in all models, suggesting that stochastic processes and/or unmeasured environmental variables also play an important role. The relative importance of local environment, landscape context, and space changed considerably when analyzing the assembly mechanisms of each functional group separately. Therefore, to recover distinct functional traits in restoration sites, it may be necessary to manipulate different components of the local environment and surrounding landscape. Overall, this study shows that assembly rules can help to better understand recovery processes, enabling improvement of future restoration efforts.

We evaluated the effects of different land-use systems on the ability of dung beetles to control the population of detritus-feeding flies. We tested the hypotheses that intensification of land use will reduce dung beetles richness, abundance and biomass and, consequently, their dung burial ability, affecting the interaction between dung beetles and flies and reducing its effectiveness as a natural biological control. In the Brazilian Amazon we sampled dung beetles, fly larvae and adults; and recorded the rate of dung removal by dung beetles across a gradient of land-use intensity from primary forest, secondary forest, agroforestry, agriculture to pasture. Our results provide evidence that land-use intensification results in a reduction of the richness, abundance and biomass of dung beetles, and this in turn results in lower rates of dung removal in the most simplified systems. We found no significant differences in the abundance of fly larvae between the different systems of land use. However, the number of adult flies differed significantly between land-use systems, presenting higher abundance in those sites with greater intensity of use (pasture and agriculture) and a lower abundance of adult flies in forested systems (primary and secondary forests, and agroforestry). Information-theoretic model selection based on AICc revealed strong support for the influence of land-use systems, dung removal rates and dung beetle abundance, biomass and richness on adult dung-fly abundance. Our results also reveal that dung beetles are not solely responsible for fly control and that other factors linked to land use are influencing the populations of these detritus-feeding insects.