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Studies focusing on the diet of insectivorous bats enhances our understanding of species foraging ecology, and the various ecosystem services provided by bats (especially regulating and suppressing pest populations). This service provides an important insight on their roles in ecosystems, and decreases crop damage as well as increasing productivity, reducing pesticide application, and as significant source of energy for cave ecosystems. This study aimed to understand patterns and provide an overview of how bat diet research has changed over seven decades, to enable more effective future research on conservation and bat pest-control related services. In this study, we reviewed and synthesized the insectivorous bat diet literature and the research which reported the dietary composition that published between 1950 and 2020 to evaluate trends and changes in research. We found studies on 374 species (33.3% of insectivorous species), and a progressive increase in research during over seven decades across all nine regions. The majority of publications were concentrated in North America (116 publications) with fewer studies in countries from the tropics. Most studies took place in natural areas (252 studies) with fewer in buildings and agroecosystems. All insectivorous-bats families were included in diet research, with Vespertilionidae having the greatest coverage (275 studies). Our synthesis highlights clear spatial and taxonomic biases in research. Future studies should focus on all and include more research in agroecosystems and urban areas to understand their roles in ecosystems as well as promote bat conservation.

Animal pollinators are globally threatened by anthropogenic land use change and agricultural intensification. The yield of many food crops is therefore negatively impacted because they benefit from biotic pollination. This is especially the case in the tropics. For instance, fruit set of Coffea arabica has been shown to increase by 10–30% in plantations with a high richness of bee species, possibly influenced by the availability of surrounding forest habitat. Here, we performed a global literature review to (1) assess how much animal pollination enhances coffee fruit set, and to (2) examine the importance of the amount of forest cover, distance to nearby forest and forest canopy density for bee species richness and coffee fruit set. Using a systematic literature review, we identified eleven case studies with a total of 182 samples where fruit set of C. arabica was assessed. We subsequently gathered forest data for all study sites from satellite imagery. We modelled the effects of open (all forest with a canopy density of ≥25%), closed (≥50%) and dense (≥75%) forests on pollinator richness and fruit set of coffee. Overall, we found that animal pollination increases coffee fruit set by ~18% on average. In only one of the case studies, regression results indicate a positive effect of dense forest on coffee fruit set, which increased with higher forest cover and shorter distance to the forest. Against expectations, forest cover and distance to open forest were not related to bee species richness and fruit set. In summary, we provide strong empirical support for the notion that animal pollinators increase coffee fruit set. Forest proximity had little overall influence on bee richness and coffee fruit set, except when farms were surrounded by dense tropical forests, potentially because these may provide high-quality habitats for bees pollinating coffee. We, therefore, advocate that more research is done to understand the biodiversity value of dense forest for pollinators, notably assessing the mechanisms underlying the importance of forest for pollinators and their pollination services.

2017-2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme, and with the funding organisations AEI, NWO, ECCyT and NSF Funding information, Allen-Perkins A, Magrach A, Dainese M, Garibaldi LA, Kleijn D, Rader R, Reilly JR, Winfree R, Lundin O, McGrady CM, Brittain C, Biddinger DJ, Artz DR, Elle E, Hoffman G, Ellis JD, Daniels J, Gibbs J, Campbell JW, Brokaw J, Wilson JK, Mason K, Ward KL, Gundersen KB, Bobiwash K, Gut L, Rowe LM, Boyle NK, Williams NM, Joshi NK, Rothwell N, Gillespie RL, Isaacs R, Fleischer SJ, Peterson SS, Rao S, Pitts-Singer TL, Fijen T, Boreux V, Rundlöf M, Viana BF, Klein AM, Smith HG, Bommarco R, Carvalheiro LG, Ricketts TH, Ghazoul J, Krishnan S, Benjamin FE, Loureiro J, Castro S, Raine NE, de Groot GA, Horgan FG, Hipólito J, Smagghe G, Meeus I, Eeraerts M, Potts SG, Kremen C, García D, Miñarro M, Crowder DW, Pisanty G, Mandelik Y, Vereecken NJ, Leclercq N, Weekers T, Lindstrom SAM, Stanley DA, Zaragoza-Trello C, Nicholson CC, Scheper J, Rad C, Marks EAN, Mota L, Danforth B, Park M, Bezerra ADM, Freitas BM, Mallinger RE, Oliveira da Silva F, Willcox B, Ramos DL, D da Silva E Silva F, Lázaro A, Alomar D, González-Estévez MA, Taki H, Cariveau DP, Garratt MPD, Nabaes Jodar DN, Stewart RIA, Ariza D, Pisman M, Lichtenberg EM, Schüepp C, Herzog F, Entling MH, Dupont YL, Michener CD, Daily GC, Ehrlich PR, Burns KLW, Vilà M, Robson A, Howlett B, Blechschmidt L, Jauker F, Schwarzbach F, Nesper M, Diekötter T, Wolters V, Castro H, Gaspar H, Nault BA, Badenhausser I, Petersen JD, Tscharntke T, Bretagnolle V, Willis Chan DS, Chacoff N, Andersson GKS, Jha S, Colville JF, Veldtman R, Coutinho J, Bianchi FJJA, Sutter L, Albrecht M, Jeanneret P, Zou Y, Averill AL, Saez A, Sciligo AR, Vergara CH, Bloom EH, Oeller E, Badano EI, Loeb GM, Grab H, Ekroos J, Gagic V, Cunningham SA, Åström J, Cavigliasso P, Trillo A, Classen A, Mauchline AL, Montero-Castaño A, Wilby A, Woodcock BA, Sidhu CS, Steffan-Dewenter I, Vogiatzakis IN, Herrera JM, Otieno M, Gikungu MW, Cusser SJ, Nauss T, Nilsson L, Knapp J, Ortega-Marcos JJ, González JA, Osborne JL, Blanche R, Shaw RF, Hevia V, Stout J, Arthur AD, Blochtein B, Szentgyorgyi H, Li J, Mayfield MM, Woyciechowski M, Nunes-Silva P, Halinski de Oliveira R, Henry S, Simmons BI, Dalsgaard B, Hansen K, Sritongchuay T, O'Reilly AD, Chamorro García FJ, Nates Parra G, Magalhães Pigozo C, Bartomeus I

Saltwater crocodiles Crocodylus porosus are listed as critically endangered in Myanmar because they are limited to Meinmahlakyun Wildlife Sanctuary (MKWS) in the Ayeyarwady delta region. Little contemporary data exists on their distribution and population size which hinders effective conservation and management. We conducted standardized spotlight surveys and camera trap surveys along the rivers inside MKWS, and two nearby reserved forests. We used Hierarchical N-mixture models, Spatial Count models, and the relative abundance index to estimate site use by and population sizes of saltwater crocodiles in the Ayeyarwady delta. To address biases in detectability, we used maximum-likelihood and Bayesian approaches (1) to assess occupancy (site use) and population parameters of saltwater crocodiles, and (2) to assay abiotic and anthropogenic factors affecting it. Saltwater crocodiles were more likely to be abundant and occupy in the waterways inside MKWS than the reserved forests, and in the narrow and low salinity waterways than the wide and high salinity ones. Abundance of saltwater crocodiles was lower in areas with the human settlements than in areas with no settlement. Creeks within MKWS had moderate salinity and no human settlement and therefore it can be regared as the last remaining optimal saltwater crocodile habitat of the Ayeyarwady Delta. We estimated the saltwater crocodile population sizes in MKWS were 75 ± 9.92 individuals as absolute spotlight index, 58 ± 8.02 individuals as the maximum likelihood estimate of the N-mixture models and 68 ± 10.00 individuals as the Bayesian estimate of the spatial count models. Current population estimates of saltwater crocodiles are lower than the previously reported population size in 1999, and the declining population is now restricted to MKWS. We suggest developing buffer zones in the reserved forests around the wildlife sanctuary to increase habitat areas for saltwater crocodiles and to improve the outlook for long-term saltwater crocodile survival in Myanmar.

More than 30% of global crop plants rely on pollinators to set fruit or seed. While several studies have documented the negative effects of habitat degradation and distance from natural habitats on pollinator diversity in tropical areas, such studies have focused on single crops in particular areas without examining entire plant-pollinator communities. Here, we compared the plant-pollinator network structure between mixed fruit orchards that were near to (7 km) tropical forests and further investigated the effect of landscape composition in surrounding areas on plant-pollinator network structure. Our ten pairs of orchards were in Thailand and grew a range of tropical fruits pollinated by insects, birds and bats. The average number of visitor-flower interactions was higher at sites near the forest. Similarly, network robustness (the resistance of the network to losing species as a result of primary species removal) and interaction evenness (evenness of interactions among species) were higher at the sites closer to the forest. Robustness was strongly positively influenced by the proportion of lowland mosaic within a 1 km radius, while interaction evenness was positively affected by the proportion of urban area and montane mosaic within a 4 km radius of each site. Conservation of (semi-) natural habitats is therefore important for maintaining the diversity of wild pollinators and agricultural production.

Recent advances in the study of pollination networks have improved our ability to describe species interactions at the community level. In this study, we compared the abundance and network strength of facultative and obligate nectar-feeding bats to determine their roles in pollinating mixed fruit orchards. We were particularly interested in the effect of distance from forests and caves on the foraging activity of these two bat groups. For this study, we examined 10 pairs of orchards; each pair consisted of one orchard near to (< 1 km) and one orchard far from (> 7 km) the forest edge. We estimated the abundance of each bat group (nectarivorous vs. frugi-nectarivorous) using video observations to determine floral visitation rates. A pollination network was then created for each of the 20 study orchards and network strength was calculated for each bat group at each orchard. We found that nectarivorous bats showed higher abundance and network strength than frugi-nectarivorous bats. Both bat abundance and network strength were negatively correlated with distance to the nearest cave, however, only network strength was affected by distance to the forest. These results corroborate the importance of nectarivorous bats in pollinating crops within southern Thailand’s mixed fruit orchards. Higher network strength of bats near forests and caves emphasizes the role of natural habitats as pollinator sources.

Background Pollinators are well known for the ecosystem services they provide, and while urban areas are generally perceived as low-quality habitat for most wildlife, these cities often support a surprising degree of pollinator diversity. The current rapid growth of urban areas and concern over global pollinator declines have spurred numerous studies examining pollinator communities in temperate cities, but knowledge about tropical urban pollinators remains scarce. Methods This study investigated the effects of habitat and landscape factors on pollinator richness and abundance in a highly-populated, tropical city: Bangkok, Thailand. We conducted pollinator observations in 52 green areas throughout the city and collected data on patch size, floral abundance, plant richness, location type, and percent vegetation at five spatial scales. Results Of the 18,793 pollinators observed, over 98% were bees. Both patch size and floral abundance generally had positive effects on pollinators, although there was a significant interaction between the two factors; these findings were generally consistent across all focal taxa (Tetragonula stingless bees, Apis honey bees, Xylocopa carpenter bees, and butterflies). Discussion Our results demonstrate the importance of maintaining large green areas in cities, since small green areas supported few pollinators, even when floral resources were abundant. Moreover, most pollinator taxa utilized a variety of location types (e.g., public parks, school campuses, temple grounds), with the exception of butterflies, which preferred parks. Our findings are generally consistent with those of temperate urban studies, but additional studies in the tropics are needed before global patterns can be assessed.

Fruit bats provide valuable pollination services to humans through a unique coevolutionary relationship with chiropterophilous plants. However, chiropterophily in the Old World and the pollination roles of large bats, such as flying foxes (Pteropus spp., Acerodon spp., Desmalopex spp.), are still poorly understood and require further elucidation. Efforts to protect these bats have been hampered by a lack of basic quantitative information on their role as ecosystem service providers. Here, we investigate the role of the locally endangered island flying fox Pteropus hypomelanus in the pollination ecology of durian (Durio zibethinus), an economically important crop in Southeast Asia.On Tioman Island, Peninsular Malaysia, we deployed 19 stations of paired infrared camera and video traps across varying heights at four individual flowering trees in a durian orchard. We detected at least nine species of animal visitors, but only bats had mutualistic interactions with durian flowers. There was a clear vertical stratification in the feeding niches of flying foxes and nectar bats, with flying foxes feeding at greater heights in the trees. Flying foxes had a positive effect on mature fruit set and therefore serve as important pollinators for durian trees. As such, semi-wild durian trees—particularly tall ones—may be dependent on flying foxes for enhancing reproductive success. Our study is the first to quantify the role of flying foxes in durian pollination, demonstrating that these giant fruit bats may have far more important ecological, evolutionary, and economic roles than previously thought. This has important implications and can aid efforts to promote flying fox conservation, especially in Southeast Asian countries.

Fruit bats provide valuable pollination services to humans through a unique coevolutionary relationship with chiropterophilous plants. However, chiropterophily in the Old World and the pollination roles of large bats, such as flying foxes (Pteropus spp., Acerodon spp., Desmalopex spp.), are still poorly understood and require further elucidation. Efforts to protect these bats have been hampered by a lack of basic quantitative information on their role as ecosystem service providers. Here, we investigate the role of the locally endangered island flying fox Pteropus hypomelanus in the pollination ecology of durian (Durio zibethinus), an economically important crop in Southeast Asia. On Tioman Island, Peninsular Malaysia, we deployed 19 stations of paired infrared camera and video traps across varying heights at four individual flowering trees in a durian orchard. We detected at least nine species of animal visitors, but only bats had mutualistic interactions with durian flowers. There was a clear vertical stratification in the feeding niches of flying foxes and nectar bats, with flying foxes feeding at greater heights in the trees. Flying foxes had a positive effect on mature fruit set and therefore serve as important pollinators for durian trees. As such, semi‐wild durian trees—particularly tall ones—may be dependent on flying foxes for enhancing reproductive success. Our study is the first to quantify the role of flying foxes in durian pollination, demonstrating that these giant fruit bats may have far more important ecological, evolutionary, and economic roles than previously thought. This has important implications and can aid efforts to promote flying fox conservation, especially in Southeast Asian countries.

Deforestation and forest fragmentation are contributing to declines in crop pollinator populations worldwide. Several studies have examined the impact of forest proximity on plant pollination ecology, but concentrated on single crop species. However, it can be more informative to investigate multiple crop and pollinator species in a community, because different pollinator groups may respond differently to forest distance. We evaluated flower visitor diversity, visitation frequency, and fruit set for three crop species (rambutan, durian and mango) in 10 pairs of mixed fruit orchards. Each pair consisted of one orchard near to (< 1 km) and one orchard far from (> 7 km) the forest edge. Rambutan fruit set was significantly influenced by distance to forest. The main visitors of rambutan flowers were stingless bees. In contrast, the dominant visitors to durian and mango flowers were nectarivorous bats and flies, respectively, and the fruit set of these crops were not significantly influenced by distance to forest. However, durian fruit set was negatively affected by distance to the nearest cave inhabited by nectarivorous bats. This study demonstrates that both caves and forests can be important pollinator sources for agricultural crops, and that the dispersal success of pollinators is related to isolation from source habitats. Maintaining forest patches and limestone karsts may provide stepping stones across fragmented landscapes, and attract greater numbers of pollinators to agricultural areas.

Variation in the acoustic structure of bat echolocation calls can often provide sufficient information for reliable and efficient species identification. The aim of this study was to investigate the use of echolocation call structure to identify a number of bats in the families Vespertilionidae, Emballonuridae, Nycteridae and Megadermatidae from Thailand. These species typically emit echolocation calls with a frequency-modulated (FM) sweep dominating part or all of their calls. A total of 510 echolocation calls from free-flying individuals were recorded throughout Thailand. According to the frequency-time spectra, these calls were categorized into four types: broadband FM (eight species), narrowband FM (seven species), long multiharmonic (four species) and short multiharmonic (three species). Discriminant function analysis was used to classify calls from individual bats to species. Correct classification levels were 85.9% for individuals emitting broadband FM calls (six species with adequate sample sizes)...

Bats are an important component of biodiversity in Southeast Asia, and are key indicators of habitat quality. Acoustic analysis of echolocation calls not only allows the identification of bat species that are difficult to capture, but also allows for rapid and standardised ways to survey and monitor bats over large areas. However keys based on call parameters must also account for geographic variation in call parameters, and consider any effects of morphology and sex on call frequency. Presence-only modelling can predict likely geographic locations of specific taxa, and can used to refine decision making so that species unlikely to occur in a specific region can be omitted from more localised acoustic libraries. Here we develop an acoustic library for the echolocation calls of rhinolophoid bats in Thailand, and use presence-only modelling (Maxent) to explore how species with similar calls in a library developed at the national level can sometimes be largely allopatric, and hence identifiable, once geographic range is predicted. Presence-only modelling can also be used to explore whether species with similar calls adjust call frequency in likely areas of sympatry. We analysed calls from fourteen species of rhinolophid and twelve hipposiderid species from Thailand. Calls from a further three rhinolophid and one hipposiderid species are also described but not analysed statistically because of small sample sizes. Even without considering geographic variation, 69% of rhinolophid (14 species with a minimum of five individuals/ species) and 91% of hipposiderid calls (12 species) could be classified successfully to species using two call parameters (frequency of most energy (FMAXE) and duration) in a discriminant function analysis. Most of the discrimination was achieved because species often utilised different frequency bands. Morphology can also affect call frequency both across and within species. In both rhinolophids and hipposiderid families there was a negative relationship between FMAXE and forearm length. Within species, FMAXE was negatively related to forearm length in Rhinolophus microglobosus, R. pusillus and R. thomasi, and positively related to forearm length in R. affinis and R. pearsonii. Male R. pusillus called at higher frequencies than females, although there was no sexual size dimorphism in forearm length. Call frequency was negatively related to relative humidity in R. pusillus, suggesting that bats called at lower frequencies in humid environments to counter increases in atmospheric attenuation. Presence-only modelling was used to show that some species with similar call frequencies (e.g., R. lepidus and R. microglobosus; R. yunanensis and R. trifoliatus are predicted to occur largely in allopatry, and so could be identified reliably in particular parts of the country. Presenceonly modeling can assist in predicting areas of overlap between species with similar call frequencies. Other species (e.g., R. malayanus, R. coelophyllus) overlap in frequency when data from all of Thailand are combined, but seem to avoid call overlap when syntopic. Hence acoustic identification can be improved by taking into account local distribution patterns and patterns of species coexistence. The creation of call libraries at a local scale would have extensive potential as a resource to monitor changes in species distributions through time.

The study of plant responses to touch, particularly the responses of leaves, stems, and roots, has a long history. By contrast, floral responses are relatively unexplored. Stigma closure is common in the Bignoniaceae, but the factors influencing it are not well understood. We investigated factors influencing stigma closure and reopening and its effects on pollen receipt in seven Oroxylum indicum trees near Hat Yai, Thailand. The effects of pressure, conspecific and heterospecific pollen, and pollen load (the amount of pollen deposited) on stigma behavior were examined in 270 flowers (of the total 430 flowers evaluated in the entire study). Pressure alone resulted in faster closure than did conspecific pollination and faster reopening than did heterospecific pollination. Stigmas never reopened after conspecific pollination. Pollen load had no effect on stigma behavior. Stigmas discriminated between conspecific and foreign pollen; they reopened only after pollination with the latter. A manipulative experiment revealed that stigma closure did not affect the number of conspecific pollen grains received. We also counted pollen tubes in styles that were either hand-supplemented with outcross conspecific pollen or open-pollinated. Pollen tube numbers were highest after light pollination (∼900 grains), indicating that interference among pollen grains may occur after pollination with very heavy loads (>6000 grains). Possible fitness consequences of these responses are discussed.

Some forest restoration techniques treat remnant shrubs as competitors of newly planted tree seedlings, often clearing shrubs and weeds before trees are planted, but such plants may have significant value in attracting seed dispersers. In this study we examined the role of remnant trees and shrubs in grassland as a tool for passive and low cost ecological restoration. We determined the species density and abundance of both seed rain and its vertebrate dispersers in relation to different microhabitats (shrub-like vs. tree-like vegetation vs. grassland patches) in a 20–ha clearing of weeds mixed with early successional woody vegetation in a lowland evergreen forest in southern Thailand. We quantified seed rain from 60 seed traps placed in each microhabitat, and compared differences in seed abundance and species richness, while also examining the effect of distance from the forest edge. We found that seed rain abundance and seed species richness were significantly different among microhabitats. Seed rain was highest under shrubs, followed by under trees and then grassland, whereas seed species richness was highest under trees, followed by under shrubs, and grassland. Distance from the forest edge affected seed rain abundance under trees only. Birds (bulbuls and flowerpeckers) were the main dispersers of seeds at trees and shrubs respectively, while bats were the primary dispersers for the grassland patches. Different seed disperser groups appear to have complementary roles, such that sites containing a mixture of vegetation types including early successional vegetation may attract significantly more seed dispersers.