Understanding how selective logging affects biodiversity is crucial to planning cost-effective conservation strategies in tropical forests, yet there is limited understanding of its impacts on fauna functional diversity in the tropical Americas. We assessed how selective logging intensification and time since logging influence multiple metrics of fauna functional integrity in the Brazilian Amazon by collecting bird and dung beetle data within 48 logging management units that had experienced varying exploitation intensities between 1.5–2.0 and 5.0–6.0 years before the faunal surveys. We investigated assemblage responses and used functional attributes to assess changes in functional diversity, specialization, originality and species rarity. Using point counts and pitfall traps, we collected 5081 records of 182 bird species and 7892 dung beetles from 45 species. Logging intensification led to significant declines in most dung beetle responses and bird body mass, whereas time since logging was a key driver of dung beetle and bird functional and taxonomic diversity. Our study presents novel empirical evidence of how logging intensification effects vary across taxa, ecological metrics and time since logging, which is key to informing forest conservation and further investigating environmental degradation impacts on tropical biodiversity.

The ecological function played by the coprophagous insects is an important issue in livestock production contexts. The role of this fauna, specially dung beetles, provides benefits to both rangelands and production performance. This interaction has been studied and reported in many scientific articles, in very different places and with diverse production contexts. However, a comprehensive review of the relationship between coprophagous insects and livestock production is still lacking. We reviewed the research studies on this topic during the past five decades, with a focus in Scarabaeidae taxon and livestock production, in order to identify further research priorities. We analysed 435 research articles. The main results were: (I) studies were mostly located in temperate broadleaf forest biome, whereas arid environments were less studied; (II) Production practices impacts category was the most studied, for which the effects produced by antiparasitic products on the coprophagous insects (n = 93; 21% of total revised articles) was the topics with major number of articles. Followed was Biology category (n = 69; 16%), then in Ecosystem function category the most frequent studies were on dung removal (n = 40; 9%), whereas in the Ecosystem Services category the most frequent studies were on biological control (n = 28; 6%); (III) Australia, Mexico, Brazil, and United States were the countries with most research articles. We identified some knowledge gaps on relevant ecological functions of this fauna, in relation to benefits to livestock production. There is a need for future research on nutrient cycling, bioturbation, effects on primary production and vegetation diversity.

One of the many ecosystem services provided by dung beetles is that of secondary seed dispersal. This paper experimentally evaluates the effectiveness of this service using the chimpanzee–dung beetle seed dispersal system in Taï National Park, Côte d’Ivoire. The study focussed on the germination rate and success of four species of seeds contained in the faeces of Pan troglodytes verus: Dacryodes klaineana (Pierre) H.J. Lam, Diospyros mannii Hiern, Pycnanthus angolensis (Welw.) Warb., and Uapaca guineensis Muell. Arg. For each species, 600 seeds, half from chimpanzee faeces and half from mother trees, were sown in nurseries at depths of 0, 2, 5, 10, and 15 cm (i.e. 120 seeds per depth; 60 from chimp and 60 from mother trees). After germination, only the seeds of Uapaca guineensis and Diospyros mannii sown at 2 and 5 cm had a >14% rate (between 14.2 and 30.8%) of germination and seedling establishment, regardless of seed origin. An increase in the depth of seed burial appears to negatively affect the probability of seedling emergence and establishment. This study shows that dung beetles have positive impacts on seed fate. However, for these plant species, the chimpanzee’s role is limited to that of primary seed dispersal.

We studied the food and habitat preferences of beetles of the subfamily Scarabaeinae in a protected tropical monsoon forest, the Wasgomuwa National Park in Sri Lanka. While gaining an insight into the capacity of different resources to support dung beetles, we tested the hypothesis that, in a landscape with a mosaic of habitat types and a diversity of large mammals, specialization facilitates coexistence of the scarabs. Pitfall traps were laid in five distinct habitat types (forest, riverine, sandy banks, scrub and grassland), and baited with five dung types (leopard, cervid, elephant, bear and buffalo). Four hundred and fifty seven beetles of 22 species in seven genera were recorded. Significant differences were seen in the species richness and abundance of dung beetles between different habitats and dung types, indicating habitat and food preferences. The highest richness of scarabs was in the riverine habitat and in leopard dung. Niche breath values of the individual species indicated differences in the degrees of specialization, while niche overlap values indicated a greater sharing of dung beetle species between similar habitats and dung types than between dissimilar ones. These findings provide evidence that selectivity of habitat, and dung, may be important in promoting coexistence among the scarabs in a tropical environment.

Dung beetles are a well-defined guild within the family Scarabaeidae, with distinctive morphological, ecological and behavioural characteristics (Halffter & Matthews 1966). Although this group has been extensively studied (Hanski & Cambefort 1991) due in part to the important role they fulfil in ecosystems (Nichols et al. 2008), little information exists regarding population size and the scale of their dispersal abilities, especially in the Neotropical region. Moreover, few studies have been devoted to exploring the population dynamics of dung beetles (Roslin 1999, 2000).

Monitoring rare and elusive species for effective management and conservation is particularly challenging and often demands the development of specialized techniques. Scat surveys have been applied to monitor a variety of rare species but relatively little attention has been given to the development of appropriate sampling designs. To determine if scat surveys could be applied to compare the distribution of species across three habitats of a fragmented region in the Brazilian Amazon, the removal of human (n = 27) and jaguar (n = 27) scat samples in forest, riparian corridor and pasture habitats was recorded for 24 hours. Dung beetles were responsible for removing the majority of samples (71%) and a generalized linear mixed effect model revealed significant influence of habitat and scat type on removal probability, with forest and riparian corridors having higher removal compared with samples in pasture habitats. Although non-invasive scat surveys can potentially address fundamental broad-scale conservation and management questions, our results demonstrate that scat surveys in the tropics must account for differences in scat removal rates between habitats and target species before conclusions can be drawn regarding patterns of habitat use.

The dispersal of seeds by howler monkeys (Alouatta palliata) and the activity of dung beetles in modulating the fate of the dispersed seed were studied at Los Tuxtlas, Mexico. Howlers consumed the fruits of 35 species of plants. The seeds of 28 of these were dispersed by the monkeys. The majority (≥90%) of the seeds dispersed by monkeys were destroyed by rodents. Rapid relocation and burial of dung by dung beetles resulted in accidental relocation and burial of large numbers of seeds shortly after deposition. Faecal clumps (20 mg) remained on the ground for an average of only 2.5 h (range 1–3 h). Ball rolling beetles transported balls up to 5.0 m from the site of deposition (range 1–5 m). Burrowing and ball-rolling dung beetles buried seeds at depths ranging from 2.5 to > 12.0cm. The deeper a seed is buried, the less likely it is to be found and eaten by rodents. Eighty percent of the species used by Alouatta as sources of fruit at Los Tuxtlas benefited by the dispersal and post dispersal service provided by howlers and dung beetles respectively. Seasonality in dung beetles abundance in the forest may influence the number of seeds per species escaping post-dispersal predation during the year. Dung beetles play not only an important ecological role in the recycling of matter and energy in the ecosystem, but also in the process of rain forest regeneration.

Dung beetles attracted to howler monkey (Alouatta palliata) and coati (Nasua narica) dung were studied for an annual cycle in the tropical rain forest of Los Tuxtlas, Mexico. Pitfall traps set for 24 h month−1 captured 1567 dung beetles of 21 species. The species Canlhidium martinto, Deltochilum pseudoparile and Canthon femoralis accounted for 62% of all individuals captured. While species overlap was high (> 80%) between diurnal and nocturnal samples and between howler monkey and coati dung baits, coati dung attracted species such as C. martinezi, D. pseudoparile and Onthophagus rhinolophus while species such as C. femoralis and Copris laeviceps were numerically dominant at howler monkey dung. Thirteen non-ball rolling dung beetle species and eight ball-rolling species accounted for 43% and for 57% of all beetles captured respectively. Dung beetles were present and active in all months of the year, but occurred in higher numbers between the months of March and October, when temperatures were higher. Relative abundance of howler monkey and coati dung in the rain forest of Los Tuxtlas was estimated at 11.2 g (fresh weight) ha−1 day−1 and at 13.0 g ha−1 day−1 respectively, a seemingly low amount for the large number of scarabs attracted to the dung.

Post-dispersal fate of seeds dispersed by large primates is well studied but little is known about this process in small frugivores like tamarins. This study in the Amazonian forest of Peru aimed at investigating if characteristics related to the defecation patterns of tamarins (Saguinus mystax and Saguinus fuscicollis) affected short-term post-dispersal seed fate, through secondary seed dispersal by dung beetles and removal by seed predators. Data on dung beetle activity were based on direct observations of 49 defecations while seed fate was studied using semi-controlled experiments (N = 458 for secondary dispersal and N = 398 for predation). Tamarins produce small defecations with a low number of seeds. Thirty-five per cent of defecations were visited by an average of 1.5 dung beetles that usually transport the faeces as pellets. Twenty-four per cent of seeds were buried by beetles at a mean depth of 3.5 cm. With increasing quantities of faecal matter, the probability of secondary seed dispersal increased but not the depth of burial. Seed predation pressure was low (17.6%) after 4 d and higher in faeces of S. mystax than in faeces of S. fuscicollis. Despite their small size, tamarins could be considered as high-quality seed dispersers, with a potential role for forest regeneration.

In a bioassay to determine non-target ecotoxicological effects of a pyrethroid spray (Ektoban®) on dung beetles, dung from both cypermethrin/cymiazol-treated and control cattle was collected one, two, three, five, seven, 14, 21 and 28 days after treatment and fed to a treatment and control group (respectively) of beetles of the species Euoniticellus intermedius (Reiche). This was done to assess whether a spray formulation of cypermethrin may affect dung beetles differently than previously tested pour-on formulations. Following three beetle generations for two weeks each, the experiment retrieved no significant differences in adult or larval survival, egg production, fecundity and fertility between the control and treatment group. These results demonstrated that the used spray formulation of cypermethrin is likely to be far less detrimental to dung beetles than previously tested pour-ons.

The rate of dung-pat degradation in cattle pastures in south west England was examined between May and September 2002, using batches of standardized, 1.5 kg, artificially-formed cow pats. In pats in which insects were allowed free access, the rate of disappearance, measured as ash-free dry weight, was faster in spring than summer and the loss of organic matter ranged between 0.69 and 1.99% per day, equating to an estimated time for complete disappearance of 57–78 and 88–111 days in spring and summer, respectively. To assess the role of colonizing insects on decomposition, six batches of pats were constructed and either left uncovered or, using fine mesh cages, were covered for 2, 7 or 14 days following deposition to exclude colonizing insects, after which they were uncovered. After 35 days all pats were then retrieved from the field, the composition of the invertebrate community within each pat was determined and the degree of degradation, measured as ash-free dry weight, was assessed. Covered pats had significantly higher rates of ash-free dry weight loss than uncovered pats. From the 180 pats that were recovered and searched, larvae of Aphodius (Coleoptera: Scarabaeidae) were the most numerous taxon collected (1435 individuals). Aphodius larvae were significantly more abundant in pats that remained uncovered or were covered for 2 days only, compared to pats that had been covered for 7 or 14 days. The results show that the exclusion of insects for as little as two days following deposition causes a significant reduction in both the insect population and the subsequent rate of pat degradation.

Many frugivorous animals disperse seeds in their faeces (Corlett 1998, van der Pijl 1982), which may enhance the ability of secondary seed dispersers and post-dispersal seed predators to locate seeds (Andresen 2001, Chapman 1989, Feer 1999, Janzen 1982). By destroying and moving seeds these animals can radically alter the primary seed shadows generated by frugivorous animals and, consequently, have the potential to influence plant recruitment (Alcántara et al. 2000, Crawley 1992). Nevertheless, the influence of faeces on seed removal in South-East Asian forests has not previously been investigated and our knowledge currently comes from studies in Neotropical forests (Andresen 2001, Chapman 1989, Feer 1999, Janzen 1982).

Anthropogenic disturbance in Amazonian forests has increased dramatically since the early 1980s and forest disturbance is expected to continue in the early twenty-first century. Logging and conversion to pasture for cattle are two of the largest causes of forest disturbance and destruction. This study examined the distribution and diversity of dung beetles (Coleoptera: Scarabaeidae) in intact forest and under three disturbance regimes (selective logging, clear-cutting and pasture) in a forest tract in southern Pará state, Brazil. Dung beetles were collected using faeces-baited pitfall traps, then identified, measured and weighed. Principal Components Analyses and the Sørensen's Index indicated that the intact and selectively logged areas were similar in terms of species composition but that the pasture areas and clear-cut areas had substantially different groups of species. Beetle size and diversity (as measured by species richness, Shannon index and Simpson's index) were lower in clear-cuts and pasture than in intact forest. The selectively logged forest was no less diverse than intact forest, and beetles were the same size or larger than those in intact forest. Total beetle biomass, however, was highest in the pasture due to the abundance of small-bodied beetles in this habitat. While the fact that selective logging has a relatively minor impact on the dung beetle community is heartening, the projected increase in the amount of highly disturbed landscape in Amazonia is expected to have a severe impact on dung beetle biodiversity in the region.

During reproduction, dung beetles of the genus Onthophagus typically bury portions of dung removed from the dung pad. Even though females are capable of successfully constructing and provisioning nests when unaccompanied by males, extensive levels of co-operation between sexes have been reported. In some species, males show a clear dimorphism in body plan and only large horned males are known to assist females. In O. taurus this form of paternal investment is facultative and depends on social context (namely the presence of other males). We studied relationships between body size and paternal investment in five Onthophagus species (i.e. O. coenobita, O. fracticornis, O. illyricus, O. taurus and O. vacca). Two types of tests were established. In test A, a large and a small male were placed with a single, medium-size female; in test B, a large and a small female were placed with a single large male. In controls one male was placed with one female. Individuals were maintained for 10 days. Then the enclosures were opened to assess the position of each beetle. When two mates were found in close vicinity or in the same tunnel provisioning dung, a co-operative behaviour was assumed. In competitive tests, small males and small females never co-operated with their potential mates whilst large and medium-size individuals often co-operated with mates inside the same tunnels. No differences in frequencies of co-operation were found between large and medium-size females. Small females and small males scarcely co-operated with large or medium-size mates in controls. These results suggest that large individuals outcompete the small ones. They also suggest that paternal investment depends on body size of both mates. Large males of all species assist medium-size and large females, whereas small males do not. However, large males do not invest much parental effort on small females that, in fact, are poorly assisted. We assume that large individuals of both sexes are reproductively superior to small ones. The propensity of both small females and small males to excavate was lower than that of larger individuals; accordingly, digging capacity could be a proximate factor explaining facultative paternal investment in these species.

The study of seed fate is crucial for understanding fruit-frugivore interactions. One factor that can greatly influence the fate of seeds dispersed through mammal defecation, is the dung that accompanies the seeds. Dung attracts dung beetles and rodents; the former eat and bury dung, the latter feed on seeds. In this study the fate of Micropholis guyanensis subsp. guyanensis seeds surrounded by no dung and by 5, 10 and 25 g of howler monkey dung was followed until seedling establishment. The depths at which dung beetles bury the seeds were measured, and the effect of burial depth on seedling emergence was determined. Although initial seed fates differed among treatments, the same percentage of seedlings established from seeds without faecal material, and from seeds with 5, 10 and 25 g of dung. However, a significantly higher proportion of seedlings established from buried seeds when compared to seeds that remained on the surface. The percentage of seedlings establishing in a controlled germination experiment decreased significantly with increasing burial depth. The effect of dung beetle activity should be taken into consideration when assessing the role that mammal endozoochory plays on seed dispersal ecology of tropical plants. These results provide further evidence for the emerging realization that the study of secondary seed dispersal and post-dispersal events is crucial for a more complete understanding of plant regeneration.

The dispersal of seeds by howler monkeys (Alouatta seniculus) and the role of dung beetles in determining the fate of the dispersed seeds were studied at Nouragues Station, French Guiana, during three 2-mo periods (April–May, 1995–97). Howler monkeys were observed to disperse seeds of 47 plant species. Monkey dung attracted 57 species of dung beetles (Scarabaeidae), including tunnellers (maximum size 37 mm) and ball rollers (12.6 mm). The rate of seed burial was negatively correlated with seed size (10 plant species) and positively correlated with dung beetle size (six species of tunnellers). More than 80% of small seeds (< 5 mm) and 30% of large seeds (22 mm), were buried by the largest tunnellers. Dung beetles buried 13 to 23% of seeds ranging 8–13 mm in width. The maximum average depth of burial was 28 cm and varied according to the species of dung beetle. The rate of disappearance of large dung clumps varied during the day and was completed by nocturnal dung beetles. Seeds of Chrysophyllum lucentifolium (Sapotaceae) buried at 5 and 10 cm depths did not suffer predation, but showed low germination success compared to seeds left at the soil surface. Dung beetles affected the survival and distribution of a portion of the seeds dispersed by monkeys, and their relative importance in shaping seed fate depended on seed and beetle size.

At Los Tuxtlas, Mexico, presence of dung and carrion beetles, were sampled using baited pitfall traps, at the following habitats: isolated forest fragments, forest edges, plantations (coffee, cacao, mixed, citrus and allspice), live fences and pastures. A total of 14,269 beetles representing 36 species were captured. Onthophagus batesi, Canthon femoralis, Canthidium centrale, Copris laeviceps, O. rhinolophus and Deltochilium pseudoparile accounted for 75% of the captures in the overall sample from 79 sites. Across forest fragments capture rates of species and individuals were associated positively to area and negatively to isolating distance. Rarefaction analysis showed that forest fragments were the most species-rich habitats followed by the mixed and cacao plantations, the forest edge, live fences and coffee, citrus and allspice plantations. Pastures were the least species-rich habitat. Horizontal and vertical diversity of the vegetation at the habitats studied influenced the species richness of dung and carrion beetles and the number of species in common between forest fragments and human-made habitats. A significant relationship existed between the number of non-flying mammals recorded at the study sites and the richness of species and individuals of dung beetles at the habitats investigated. The relevance of this information is discussed in the light of the ecological flexibility of dung and carrion beetle species and of possible conservation scenarios involving landscapes in which isolation of forest fragments is reduced by the presence in open areas of human-made vegetation such as plantations of cacao, coffee, cacao and coffee and live fences.

Dispersal of seeds away from the parent plant may facilitate escape from density-dependent seed mortality. However, many post-dispersal events can have a profound influence on the survival of dispersed seeds. By incorporating seeds in the dung that dung beetles process for consumption and oviposition, dung beetles could enhance seed survival if they remove seeds from areas of high predation risk and place them in locations that avoid subsequent predation and that are suitable for germination. The role of dung beetles in seed survival was investigated over 15 mo in Kibale National Park, Uganda. Depths of seeds buried by beetles, levels of predation on buried and unburied seeds, and germination success of seeds buried to different depths were examined. Results suggest that by burying seeds dung beetles increase the probability that seeds will escape predation and germinate. Of seeds placed in dungpiles, 69% remained at the surface, while 25% were buried from 1–3 cm in depth. Larger seeds were buried more shallowly than smaller seeds. Buried seeds were less likely to be removed by predators than seeds at the surface. Germination of seeds buried at 1- and 3-cm depths was significantly higher than seeds buried at 10 cm. For the species tested, many seeds were buried by dung beetles between 1 and 3 cm and at this depth there was a high probability of escaping predators and germinating. This demonstrates the potential ecological importance of dung beetles in facilitating seed survival and provides data to consider the role of dung beetles in the evolution of seed attributes.