Itaipu Hydroelectric Power Plant initiated a large reforestation programme after the expropriation of the areas destined for the formation of the reservoir. This study aimed to evaluate the effectiveness of forest restoration of the Seasonal Semideciduous Forest in the Upper Paraná Atlantic Forest ecoregion, Brazil, using epigaeic ant assemblages as bioindicators, by comparing ant species richness and composition in the Reservoir Protection Strip with adjacent areas, such as the primary forest of the Iguaçu National Park and the Permanent Preservation Area located on a rural property and agricultural areas. In total, 171 ant species were identified. Ant species richness was higher in forest than in agricultural areas and did not differ among forest areas. However, ant species composition in forest areas, regardless of the restoration technique used, was not similar to the primary forest, possibly due to variation in forest recovery time. This study highlights the great value of the Iguaçu National Park as a conservation unit. Also, it reveals that the efforts for the creation and maintenance of the Reservoir Protection Strip, which remains without anthropic interventions for years, might indeed lead to a complete recovery of the ant species composition over time, reinforcing their great importance for biodiversity conservation.

Conversion of primary forest into oil palm plantations is common in tropical countries, affecting soil properties, ecosystem services and land-use management. However, little is known about the short-range spatial soil distribution that is important for soil scientists, ecologists, entomologists, mycologists or microbiologists. In this study, seven soil properties (pH, EC (µS/m), P (mg/kg), NO3- (mg/kg), N%, C% and C:N) were measured to quantify the spatial autocorrelation across primary forest, selectively logged forest and oil palm plantation in Sabah, Malaysian Borneo. Local variograms were calculated (range ∼5 m) to determine the short-range variation, and a decision tree as well as principal component analysis were implemented to determine if the overall (global) mean differed between land uses. As hypothesised, oil palm soils deviated the most from primary forest soils, which had more fluctuating variograms and in general, a shorter range. Oil palm plantations also showed a difference in the global mean except for electrical conductivity. Selectively logged forests also differed in their short-range spatial structure; however, the global mean and variance remained similar to primary forest soil with the exception of labile phosphorus and nitrate. These results were attributed to initial plantation development, removal of topsoil, fertiliser application and topography.

Long-term climate and vegetation data were used to determine the role of rainfall variability and its seasonal distribution on litterfall nutrients. Based on a 20-year data set on rainfall (range 334–1,506 mm per year) and litterfall nutrients from old-growth tropical dry forest (TDF) in Mexico, we examined litterfall N and P concentrations from the rainy and dry seasons in response to rainfall in the rainy (June–October) and the dry (November–May) seasons, the latter referred to as out-of-season precipitation (OSP). Rainy-season litterfall N concentrations, but not P concentrations nor N:P ratios, changed positively (p < 0.001) in response to rainy-season precipitation. Dry-season litterfall N concentrations and N:P ratios, but not litterfall P, increased (p ≤ 0.02) in response to rainfall from the preceding rainy season. N:P ratios of dry-season litterfall in years with OSP were higher only during dry years and N concentrations decreased in wet years (p < 0.05). The narrow range in dry-season litterfall P concentrations (1.00–1.15 mg g-1), irrespective of rainfall amount and OSP, suggests P conservation. The variation in litterfall N, but not litterfall P, in response to rainfall variability reveals a divergent nutrient response along steep changes in water availability in this TDF.

Oil palm is one of Southeast Asia’s most common crops, and its expansion has caused substantial modification of natural habitats and put increasing pressure on biodiversity. Rising global demand for vegetable oil, coupled with oil palm’s high yield per unit area and the versatility of the palm oil product, has driven the expansion of oil palm agriculture in the region. Therefore, it is critical to identify management practices that can support biodiversity in plantations without exacerbating negative impacts on the environment. This study focuses on day-flying Lepidoptera (butterflies and moths), which contribute to the ecosystem functioning as pollinators, prey, and herbivore species. We assessed whether density and behaviours of day-flying Lepidoptera varied between different habitats within oil palm plantations and across seasons. We surveyed the density and behaviours of Lepidoptera communities in mature industrial oil palm plantations within the Biodiversity and Ecosystem Function in Tropical Agriculture (BEFTA) Programme sites, in Riau, Indonesia. We surveyed two distinct habitats within the plantations in March and September 2013: Edge habitats, which were bordered by plantation roads on one side, and Core habitats in the centre of oil palm planting blocks. We conducted analyses on the effect of habitat type and season on both the overall density and behaviour of Lepidoptera communities and, independently, on the most common species. In our surveys, we observed 1464 individuals across 41 species, with a significantly higher density in Edge than in Core habitats. While there was no significant difference between overall density in March and September surveys, there was an interaction between season and habitat, with density increasing more markedly in Edge than Core areas in September. There was also a significant effect of habitat and season on behavioural time budget for the community as a whole, with more active behaviours, such as foraging and mating, being recorded more frequently in Edge than Core habitats, and more commonly in September than March. The effect of habitat type, season, and their interaction differed between the six most common species. Our findings indicate that Lepidoptera abundance is affected by habitat characteristics in a plantation and can therefore be influenced by plantation management practices. In particular, our study highlights the value of road edges and paths in plantations for day-flying Lepidoptera. We suggest that increased non-crop vegetation in these areas, achieved through reduced clearing practices or planting of flowering plants, could foster abundant and active butterfly communities in plantations. These practices could form part of sustainability management recommendations for oil palm, such as those of the Roundtable on Sustainable Palm Oil.

A trade-off between structural and chemical defences against herbivory in woody plants is alleged to depend on edaphic factors in African savannas. We studied anti-herbivory traits, in an edaphic mosaic of fertile and infertile soils within a savanna landscape in East Africa, towards elucidating herbivory defence traits expressions in woody plants of African savannas. We used data of 81 plants for 8 species from 8 sites — four sites from fertile soils (42 plants) and another four sites from infertile soils (39 plants). We did not find a general divide between structural and chemical strategies in our data. Instead, we found a range of defence traits combinations. Our results highlight that in woody plants of African savannas, chemical and structural defences can augment each other, and not necessarily trade-off. The diversity of herbivores, ranging from insects to mesobrowsers, may have driven the evolution of multiple defence strategies within the African savannas.

Ferns (Polypodiophyta) are an abundant floral element of the tropics with high sensitivity to environmental conditions and good indicators of overall biodiversity. Here, we set out to identify which geochemical factors determine fern diversity in a low-montane tropical rainforest in Eastern Ecuador. We conducted a field survey of high-spatial resolution completing a comprehensive fern inventory across two elevational ranges, combined with biochemical characterisation of the underlying soils. While α-diversity was negatively correlated with cation exchange capacity (CEC) and with elevation, β-diversity increased with elevation and with geographic distance, as predicted. Our results confirm that ferns have a high sensitivity to both elevational and environmental gradients, where the latter in this study was derived from enhanced aluminium, iron and calcium contents in some of the studied soils. Further monitoring of fern communities could therefore help to better understand and predict how environmental change may impact biodiversity, with a particular focus on threats potentially arising from toxic elements being released in tropical soils through modified soil CEC.

Monoon liukiuense (Annonaceae) is an endangered tree species distributed in Iriomote Island and Hateruma Island in the Ryukyu (Nansei) Islands, Japan, and in Orchid Island (Lanyu) in Taiwan. While its habitat is confined to small areas surrounded by human-altered landscapes, the matured trees bear abundant fruits, and many offspring grow under the mother trees. M. liukiuense is hypothesised to have lost effective seed dispersers. To test this hypothesis, fate of its seeds and the behaviour of frugivores were observed using time-lapse photography during three fruiting seasons from June 2015 to August 2016 in Iriomote Island, Japan. Although several animal taxa were observed to consume the fruit pulp, only two volant animals, namely the Yaeyama flying fox and large-billed crow, were proposed as seed dispersal agents for M. liukiuense. The present study shows that an average of 82% of the fruits in the canopies fell directly beneath the fruiting trees and an average of 90% of the seeds on the forest floor remained in their original positions. These results suggest that M. liukiuense has lost most of its seed dispersal agents and the chance to expand its distribution.

The bushy-tailed opossum (Glironia venusta) is a small arboreal marsupial found in the Amazon basin. G. venusta is rarely seen and has few published sightings throughout its range. Videos (N = 79) were obtained from arboreal camera traps located in the Las Piedras Amazon Center near the Las Piedras River (SE Peru) from April 2017 until November 2017. Our new records, the first for the Las Piedras River, demonstrate that the species is nocturnal with activity peaks at 3:00 h and 20:00 h in the hours of complete darkness. The abundance of camera trap footage of such a rarely observed species further demonstrates the effectiveness of arboreal camera trapping to conduct species assessments.

Male and female dioecious tropical trees are subjected to distinct demands that may influence their ecology. An example is Myrianthus holstii Engl. that produces persistent fruit eaten by elephants and other large mammals that frequently damage the trees. Myrianthus holstii populations were assessed with 24 2-km transects, spanning an elevation range of 1435–2495 m in the Bwindi Impenetrable National Park in Uganda. Of 1089 stems ≥ 5 cm diameter 449 were female, 383 were male and the rest were non-fertile. We also noted one apparently monoecious individual. Males produced flowers at smaller sizes than did females (minimum recorded diameters 5.5 cm and 6.8 cm, respectively). Both sexes had similar distributions, favouring moderately closed forest and mid-slope locations. Female trees were more frequently damaged and typically slightly shorter than males at large diameters. Seedling densities were positively associated with the presence of larger female trees. Our results are consistent with a life history where both sexes have similar requirements, but fruiting females experience a greater frequency of severe damage.

Peru contains the second largest surface area of the Amazon biome. The Peruvian Amazon is threatened by logging, illegal crops, mining, and agricultural expansion. While a number of national parks exist in the Amazon region, privately managed areas like Conservation Concessions can be an attractive complement to existing parks. We compare medium and large mammal communities in a Conservation Concession in Ucayali with the nearby Parque Nacional Sierra del Divisor National Park and describe species relative abundance and richness of both protected areas. Results suggest that Conservation Concessions can harbour an important diversity of mammal species and could provide connections to larger protected areas. However, they are no substitutes for large protected areas, especially for sensitive and threatened species. Further research is needed to demonstrate their complementarity and improve landscape-level connectivity between conservation models.

While mixed-species flocks of birds (hereafter ‘flocks’) have been widely studied, few studies have looked at the effect of habitat structure on flock presence and flocking propensity within a site. Here, we employ a use-availability approach in locations with flocks and random locations to ask whether habitat characteristics influence the presence of flocks, and whether structurally similar microhabitats support compositionally similar flocks. We also examine the effect of habitat on flock size and species richness, and the effect of intraspecifically gregarious flock participants on habitat selection. We find that flocks use a narrow subset of available tree density and canopy cover variation and prefer relatively less-dense areas with large trees and a complex foliage structure. Similar microhabitats do not result in compositionally similar flocks, and while foliage complexity was associated with flock size, no habitat characteristics influenced species richness. Flocks led by the intraspecifically gregarious western crowned warbler (Phylloscopus occipitalis), a potential nuclear species, showed preference for high foliage complexity and tree density. Thus, habitat preferences of intraspecifically gregarious species, which are followed by other species, could play a strong role in habitat selection in flocks. This suggests that degraded forests that cannot provide a suitable range of tree density, canopy cover, and/or complex vegetation structure may not support some core flock species around which flocks form, which may lead to decreased flocking in those patches.

The conservation of tropical biodiversity depends not only on forest remnants, but also on anthropogenic land covers. Some shade crops are considered wildlife-friendly agroecosystems, but their conservation value is context- and taxon-dependent. Amphibians and reptiles have received less attention despite their high sensitivity to habitat disturbance. We determined the conservation value of lightly-harvested rustic cocoa plantations for herpetofauna in the Lacandona region, Mexico. We compared 12 environmental variables between habitats. Then, we compared the abundance, species number and composition of amphibian and reptile assemblages. Within each habitat, we explored the relationships between environmental variables and abundance and species number. Tree density, litter cover and litter depth were higher in cocoa. Abundance of reptiles and amphibians were higher in cocoa than forest; species number did not differ. Habitat explained some of the variation (8%) in assemblage composition. In cocoa, amphibian abundance was positively related to canopy height and the presence of a humus layer, while reptile abundance was negatively related to relative humidity. We conclude that lightly-used rustic cocoa plantations can be suitable habitat for forest herpetofauna. As long as cocoa plantations do not replace existing forest cover, they can play an important role in the design of wildlife-friendly tropical landscapes.

Termite mounds have been poorly studied in tropical rainforest in contrast to those of savannahs where they create fertility hotspots and influence the spatial pattern of vegetation. An inventory of termite mounds and of 15 tree species with a diameter at breast height ≥ 10 cm was carried out in two 800-ha blocks, in two rainforest sites located in northern Congo. We used inhomogeneous and intertype K functions to study the spatial pattern of termite mounds and of tree species around mounds, respectively. We found that mounds in Loundoungou were over-dispersed within a radius of less than 70 m, while those in Mokabi were randomly spaced. Tree species within a 20-m radius around a mound were aggregated towards the mound, e.g. Entandrophragma cylindricum, randomly distributed, or even repulsed by the mound. The specific responses also differed in the two sites. These results suggest that (i) the mounds in Loundoungou were created by savannah termite species 3,000-2,000 years BP during the Late Holocene Rainforest Crisis and (ii) the mounds in Mokabi are characteristic of forest mounds. The impact of termite mounds on the spatial pattern of tree species is thus site-dependent, and these differences might be due to species seed dispersal strategies and to soil calcium concentrations.

The complete life history of the kleptoparasitic ‘sundew flower fly’, Toxomerus basalis, is presented and illustrated. Adults of this species are photographed alive for the first time, including video recordings of larval and adult behaviour. Adult flies of both sexes visit Drosera (sundews) and show territorial behaviour around the plants, avoiding the dangerous sticky traps and demonstrating recognition of their larval host plant. Females lay eggs directly on non-sticky parts of the Drosera host plants, such as on the lower surface of the leaves and flower stalks, but apparently also on other plants growing in close proximity with the sundews.

Many bromeliads occur in habitats that are potentially affected by salt. Pitcairnia halophila is a particularly interesting case in this context due to its growing sites in the spray zone of coastal cliffs in Central America. We conducted an experimental/observational study that explored the physiological and ecological basis of the occurrence of this species. Germination of P. halophila was as affected by increasing salinity as that of congeneric species from other natural growing sites, but seedling growth was less impaired in comparison and remained positive even at exposure to half-strength seawater. Interestingly, in situ plant nutrient concentrations documented over an entire growing season suggest that this capacity to tolerate salt stress is not tested at the natural growing site – Na+ concentrations were consistently low in leaves and shoots and comparable to those of seedlings watered with distilled water in the laboratory. We conclude that P. halophila shows the physiological ability to deal with medium levels of salinity, but ecological conditions at the humid tropical growing site allow these plants to avoid salt stress entirely in spite of the close proximity to the sea.

Predator–prey dynamics are an important aspect of community ecology, but predation events are often difficult to observe. Among African primates, observations of mammal predation are particularly uncommon and generally restricted to a few ape and cercopithecoid species. I report five observations of mammal predation by golden-bellied mangabeys (Cercocebus chrysogaster) living in rainforest at the LuiKotale study site, Democratic Republic of the Congo. Over 46 all-day follows, mangabeys from one group caught and consumed four duikers (Cephalophinae spp.) and one Alexander’s cusimanse (Crossarchus alexandri). Individuals begged from the feeding individual in three of five observations. I observed one successful attempt at begging, which resulted in an adult female tolerating removal of blue duiker by a juvenile. These are the first detailed observations of mammal predation and food sharing by Cercocebus mangabeys and suggest mammals that feed alongside mangabeys may balance predation risk against social foraging benefits. Food sharing is rarely observed in most cercopithecine monkeys and could provide a useful metric to examine socio-ecological patterns of food acquisition.

Several studies of hurricane damage on epiphyte communities implied that epiphytes might be in danger of being blown off their host when subjected to strong wind. There is very limited knowledge about the mechanical impact that wind may have on epiphytes. Using a wind-triggered camera set-up, we observed how epiphytic tank bromeliads are affected by wind. Despite offering a relatively large area of ‘attack’ to the airflow, bromeliads moved relatively little themselves. Rather than being directly moved by wind, the bromeliads in the upper crown of tall trees moved with the sway of the branches. Only when the substrate did not move, bromeliads with long broad leaves showed considerable disturbance due to wind. Our observations underline the complexity of the system and emphasise that our current understanding of the mechanical aspects of the epiphyte–host system is still very limited.

Tropical forest ecosystems are rich in epiphytes that make up a significant portion of the overall plant diversity. However, epiphytic plants are often understudied due to inaccessibility and the lack of basic ecological information poses challenges to their conservation, particularly in a time of rapid global change. The mule-ear orchid, Trichocentrum undulatum (Orchidaceae), is a large flowering epiphyte found in southern Florida (USA), the Greater, and Lesser Antilles including Cuba. The plant is Florida state-listed as endangered with only one remaining small and declining population in a coastal mangrove forest due to historical extraction and habitat destruction. Currently, there is no systematic understanding of the species’ habitat requirements. To fill this void, we compared the habitat and microhabitat of the species on its northern distribution edge (southern Florida) and the core range (in Cuba). The Florida population has only one host species, Conocarpus erectus, found in one habitat type. This is in sharp contrast to the 92 documented hosts and 5 habitats across 8 provinces in Cuba. Based on our findings from Cuba, we suggest conservation and restoration options in Florida by proposing potential suitable host plants and habitats. Proactive restoration of this species will help to ease the threat from sea-level rise to the species by securing and expanding range margins.

Tropical montane systems are characterized by a high plant species diversity and complex environmental gradients. Climate warming may force species to track suitable climatic conditions and shift their distribution upward, which may be particularly problematic for species with narrow elevational ranges. To better understand the fate of montane plant species in the face of climate change, we evaluated a) which environmental factors best predict the distribution of 277 plant species along the Himalayan elevational gradient in Nepal, and b) whether species elevational ranges increase with increasing elevation. To this end, we developed ecological niche models using MaxEnt by combining species survey and presence data with 19 environmental predictors. Key environmental factors that best predicted the distribution of Himalayan plant species were mean annual temperature (for 54.5% of the species) followed by soil clay content (10.2%) and slope (9.4%). Although temperature is the best predictor, it is associated with many other covariates that may explain species distribution, such as irradiance and potential evapotranspiration. Species at both ends of the Himalayan elevational gradient had narrower elevational ranges than species in the middle. Our results suggest that with further global warming, most Himalayan plant species have to migrate upward, which is especially critical for upland species with narrow distribution ranges.

Animals which migrate by flying should be subject to selection for optimal wing characteristics that maximize energy efficiency during migration. We investigated wing shape and wing area variation in the Globe Skimmer Dragonfly Pantala flavescens, which has the longest known migration of any insect. Wing shape and wing area differences between individuals in southern Peninsular India, and migrating individuals at a stop-over site on the Maldives, were compared. Results suggest that individuals which successfully reached the Maldives, on their way from India to Africa, had a broader wing base and an overall more slender wing shape than individuals in southern India. Contrary to our expectations, wing area did not differ significantly in most of our comparisons between southern India and the Maldives, suggesting that wing shape is more important than wing area for successful migration in P. flavescens. The results provide indirect evidence of natural selection on wing shape in a migrating dragonfly.