Roller dung beetles play a pivotal role in the nutrient distribution in soil and secondary dispersal of seeds. Dung beetles are sampled either using a dung-baited pitfall trap or an exposed dung pile on the ground. While the former method is useful for a rapid survey of dung beetles, information on the ecology and behaviour of dung beetles can be lost, which the latter method provides, but underestimates species diversity due to its inefficiency in trapping rollers. Efficiency of a new method for sampling rollers—installing guarding pitfall traps around dung piles—is assessed in three habitats—contiguous tropical rainforests, fragmented forests, and disturbed used home gardens—and two diel periods—day and night. Five guarding pitfall traps were installed at 50 cm radius around dung piles. About 98% of the total rollers were sampled in pitfall traps. The habitats were similar when the roller catches of only dung piles—conventional approach—were analyzed, but were different when the rollers of guarding pitfall traps were considered. The roller abundance was negatively affected by forest fragmentation and land-use change. About 98% of the rollers were collected at daytime. Using guarding pitfall traps around dung piles is highly recommended for dung beetle diversity studies.

In seasonal wet Neotropical forests, many studies have suggested that species-rich terrestrial frog assemblages are regulated bottom-up by the abundance of leaf litter. However, terrestrial frogs are prey to a diverse community of predators, and no studies have tested for top-down effects of predators on this or other anuran assemblages. Here, we used an extensive field dataset to model the relative contribution of food resources, microhabitat resources and predators towards the occupancy and detection of two frog species (Craugastor bransfordii and Oophaga pumilio) at La Selva, Costa Rica. Frog occupancy was most strongly influenced by predatory spiders and secondarily influenced by the abundance of leaf litter. Predators exerted stronger effects on frogs than food resources, and frogs avoided predators more as leaf litter decreased. Detection probability was elevated when predators were present. We found support for bottom-up effects of leaf litter on the terrestrial frog assemblage, but top-down effects by predators exerted stronger effects on frog occupancy and detection. Because predator avoidance varied along a resource gradient, predator and resource effects appear to be dependent, supporting interactions between top-down and bottom-up mechanisms. Climate-driven decreases in leaf litter may drive decreased availability of frog refugia and increased interactions between frogs and predators.

Knowledge on cheetah population densities across their current range is limited. Therefore, new and efficient assessment tools are needed to gain more knowledge on species distribution, ecology and behaviour. Scat detection dogs have emerged as an efficient and non-invasive method to monitor elusive and vulnerable animal species, like cheetahs, due to the dog’s superior olfactory system. However, the success of locating scat using detection dogs can be significantly improved under suitable weather conditions. We examined the impact of temperature, humidity and wind speed on detection rates of scat from cheetahs during a scat detection dog survey in Northern Kenya. We found that average wind speed positively influences the scat detection rate of detection dogs working on leash. Humidity showed no significant influence. Temperature showed a strong negative correlation with humidity and thus was excluded from our model analyses. While it is likely that wind speed is especially invalid for dogs working off leash, this study did not demonstrate this. Wind speed could thus influence the success of monitoring cheetahs or other target species. Our findings help to improve the survey and thus maximise the coverage of study area and the collection of target samples of elusive and rare species.

The spatial distribution of Neotropical birds at local scales is often associated with plant successional stages and unique microhabitats such as bamboo stands and treefall gaps. Only 15% of the Atlantic Forest remains, yet this habitat is home to more than 200 endemic birds. Understanding the distribution of bird species within the Atlantic Forest can improve the test of ecological hypotheses related to habitat use and habitat selection. This study analyses the distribution of birds among different types of relief (lowlands, ravines, hillsides, and hilltops) in 41 forest fragments of different sizes (1 to 384.5 ha) within the Atlantic Forest, south east Brazil. The presence and absence data were analysed with dynamic occupancy models to determine the influence of area and topography in the distribution of bird species. Of the 169 species detected, we were able to estimate an occupancy probability of 67. Among them, relief type was an important variable for 26 species (39%). Most species showed a preference for lowlands and ravines, and some showed an association of combinations of these two reliefs with hillsides and hilltops. These preferences might be related to distribution of preferred food, nesting microhabitats, and thermoregulation. For the endemic and threatened Atlantic Forest mountain birds, the ecological association with areas of relief is a strong, and previously unsuspected, spatial distribution pattern. Our results suggest that the ecology and distribution of birds in tropical forests across hilly regions could be better understood if topography is considered. This pattern should be better investigated among other taxa in tropical forests.

The co-occurrence of similar species in a particular environment may be facilitated if they specialise on different microhabitats, reducing competition between them. In some cases, two species prefer the same microhabitat, but one is competitively excluded to its harsh margins. In this study, we assessed microhabitat preferences and competition between two species of millipedes in Costa Rica. (1) We observed them in the wild and found Nyssodesmus python most often on wood, less often on leaves, and rarely on rocks. Spirobolida was found most often on leaves, less often on wood, and never on rocks. (2) We tested their preferences in the lab and found that N. python preferred wood to rocks, wood to leaves, and rocks to leaves. Spirobolida preferred leaves to rocks, leaves to wood, and wood to rocks. (3) We tested interference competition by placing both species together in an arena in which they both had the same preference (wood vs. rocks). Both species chose to cohabitate in the same wood, indicating that one species did not directly exclude the other. In N. python and Spirobolida, co-occurrence is facilitated by differences in microhabitat preferences and not because competition forces one species out of its preferred microhabitat.

Fruits are a major food resource for wildlifes and have evolved different traits which attract specific frugivores and facilitate seed dispersal. This study examines the quantity of the frequency of fruit tree species, distribution amongst fruit traits and estimates the potential availability of the fruit resource for frugivores in a 16-ha permanent forest plot at Doi Suthep–Pui, Thailand. The similarity amongst traits for fleshy fruited species was explored using Principal Component Analysis (PCA). Fleshy fruited species comprised 122 of 208 tree species >2 cm diameter at breast height (DBH) recorded in the permanent plot. Amongst fleshy fruited species, small fruits (length <20 mm) were most common (63.16% of species) while large fruits were rare (4.1%). Black was the most common fruit colour (43.4%). Principal Component Analysis of fruit traits explained 57% of total variance on the first three axes, and allowed identification of three species groups. Litsea martabanica and Persea gamblei are the greatest density and represented the major PCA group; black, small-sized and thin husk indehiscent fruits. These fruiting trees scattered throughout the permanent plot and were of good regeneration status. Indicating fleshy fruit can be a food resource for frugivores especially small-sized fruit. Furthermore, large-fruited species such as Madhuca floribunda is low density but important to preserve for food resource of large frugivores. This finding is very important not only for forest protection policy but also for wildlife conservation as food resources.