Search

Slugs are important consumers of fungal fruiting bodies and expected to carry their spores. In this study, we examined whether slugs (Meghimatium fruhstorferi) can act as effective dispersers of spores of basidiomycetes. The microscopic observation confirmed the presence of basidiospores in feces of field‐collected slugs, and the DNA metabarcoding study revealed that Ascomycota and Basidiomycota were major fungal taxa found in the feces. In Basidiomycota, the dominant order was Agaricales followed by Trichosporonales and Hymenochaetales. The laboratory experiments using Tylopilus vinosobrunneus showed that slugs carried a large number of spores in their digestive tracts. It was also observed that Pleurotus, Armillaria, and Gymnopilus spores excreted by slugs had a higher germination capacity than control spores collected from spore prints. The field experiments showed that slugs traveled 10.3 m in 5 h at most by wandering on the ground, litter layers, wood debris, and tree trunks. These results suggest that slugs could carry spores of ectomycorrhizal, saprophytic, and wood‐decaying fungi to appropriate sites for these fungi to establish colonies. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: This study illuminates the underappreciated role of invertebrates in seed dispersal, extending beyond the well‐documented contributions of ants. Focusing on Monotropastrum humile (銀竜草 [silver dragon plant] or 水晶蘭 [crystal orchid]), a non‐photosynthetic plant known for its minuscule, dust‐like seeds, the present research uncovers their seed dispersal roles of woodlice and earwigs in Japan. Remarkably, these invertebrates include the smallest known endozoochorous seed dispersers. Summary: Endozoochory, or internal seed dispersal through the digestive tracts of animals, has been less studied in invertebrates compared with vertebrates. Nonetheless, endozoochory is plausible whenever seeds are small enough for ingestion by frugivorous animals, suggesting a potential role for invertebrates in seed dispersal, especially for plants with minute seeds.Monotropastrum humile (Ericaceae), characterized by its fleshy fruits and dust‐like seeds, is known to utilize invertebrate agents such as camel crickets and cockroaches for seed dispersal. Here, we investigate this seed dispersal mechanism using time‐lapse photography, feeding experiments, and seed coat anatomy analysis, particularly focusing on interactions among undocumented invertebrate internal seed dispersers.Field observations indicated that in the studied population, M. humile fruits were primarily consumed by camel crickets, woodlice, and earwigs. Their effectiveness as seed dispersers varied, with camel crickets primarily acting as dispersers, whereas earwigs and woodlice were more inclined toward seed predation. Nonetheless, some seeds defecated by earwigs and woodlice remained intact, suggesting that they could also function as dispersal agents.The woodlouse Porcellio scaber is now recognized as the world's smallest internal seed dispersal agent. Combined with earlier discoveries, such as seed dispersal by camel crickets, cockroaches, and ants, and the fact that P. scaber is an exotic species in the study site, M. humile likely depends on a broad spectrum of local invertebrates. The engagement of multiple invertebrate dispersers may enhance seed dispersal across diverse habitats. [ABSTRACT FROM AUTHOR]

Minerals are among the important nutritional components that are indispensable for animals. In particular, the acquisition of sodium is important for plant‐feeding animals because sodium may be deficient for these animals as plants do not need sodium. This study compiled data on the mineral contents of leaves in 28 forests in Japan, with special emphasis on the effect of distance from the sea and bedrock type. The aim of this study was to provide basic data on mineral availability for forest‐dwelling folivores, which provide important baseline data for understanding the mineral acquisition strategy of plant‐feeding animals. Sodium and phosphorus contents of live leaves were lower than the levels required for folivores (captive non‐human primates and ungulates). The effect of the distance from the sea was evident only for magnesium and sodium. The sodium content of live leaves was high enough to satisfy folivores' requirements at only a few hundred meters from the sea. The live leaves in forests growing on sedimentary bedrocks contained more minerals than those on granite/rhyolite. Seasonality was also evident based on repeated sampling at three study sites. The mineral contents of dead leaves at the three study sites showed similar inter‐site and inter‐season variations to those of live leaves. Phosphorus and potassium contents in dead leaves were consistently lower and iron content was consistently higher than in live leaves. [ABSTRACT FROM AUTHOR]

Despite the well-known visual attraction function of angiosperm petals, additional roles of these floral organs (e.g. the provision of landing-site platforms for pollinators) have rarely been examined. This is likely because most petals perform multiple functions, making it difficult to isolate the importance of landing sites in pollination success., We investigated the landing-site function of dull-coloured pinnately branched petals in Mitella pauciflora flowers, which are predominantly pollinated by fungus gnats. We conducted a field experiment, in which the effects of experimental petal removal on pollinators' approach, landing and visit duration and floral reproductive success were examined in naturally pollinated flowers., According to direct and time-lapse camera observations, petal removal did not influence pollinators' approach frequency or visit duration, but did significantly decrease their landings. Fruit set and pollen dispatch both significantly decreased with petal removal, indicating that petals promote female and male reproductive success in M. pauciflora by facilitating pollinator landing., This demonstrates that inconspicuous petals primarily have a landing-site function rather than a visual attraction function in M. pauciflora. Discriminating between diverse petal functions is a challenging problem, and new approaches are required to elucidate the functional features of angiosperm flowers., A is available for this article. [ABSTRACT FROM AUTHOR]

No recent attempt has been made to survey dhole distribution, or to estimate remaining population numbers. We surveyed 15 protected areas in Thailand with camera traps from 1996 to 2010. We used the photo locations of dholes (n=96) in the maximum entropy (MaxEnt) model along with six environmental variables to model current dhole distribution, as well as species predictive occurrence layers for sambar, red muntjac, wild boar, tiger, and leopard. The MaxEnt model identified the predicted probability of the presence of leopards and sambar as positive and the most important variables in modeling dhole presence, indicating that maintaining a sufficient prey base may be the most important factor determining continued survival of dholes. Roughly 7% of the total land area in Thailand is potentially suitable for dholes. However, surveys to date have focused on protected areas, which make up just a third of the potential suitable areas for dholes. Only in four protected areas do they occur across the entire landscape, suggesting that in the majority of places where they occur, habitats are not uniformly suitable. Using the model, we identified several potential areas where dholes have not been reported, and therefore status surveys are needed, and where future research of the species might be focused. [ABSTRACT FROM AUTHOR]

Abstract: I summarize the current knowledge of frugivory and seed dispersal by hornbills in tropical forests. Many studies report on frugivory by hornbills but few specifically identify hornbills as effective dispersers. Hornbills are able to disperse a diverse array of fruits in tropical forests (748 plant species from 252 genera and 79 families) and move many of the seeds far from the parent trees. They digest only the fleshy parts of fruits that they swallow and then regurgitate/defecate the seeds intact. The relatively long seed retention times (>1 h) and propensity for depositing seeds away from the parent trees while foraging suggest high-quality dispersal. Some seeds might be aggregated at nest and roost sites, but hornbills are capable of dispersing seeds over several kilometers, resulting in a relatively even spread of seeds throughout the forest. Based on the results summarized here, hornbills provide excellent seed dispersal services to tropical plants in their respective habitats. [Copyright &y& Elsevier]

Hornbills (Bucerotidae) are widely regarded as important seed dispersers in tropical forests in Africa and Asia. We investigated how the roosting behavior of wreathed hornbills ( Aceros undulatus) influences seed deposition and seedling survival at a roost site in a moist evergreen forest of Khao Yai National Park, Thailand. Fallen fruits and seeds were collected in traps that were placed around a roosting site for 14 months, and seedlings were monitored in adjacent quadrats for 3 years. Seedfall and seedlings of species represented in the hornbill diet occurred at significantly higher densities in the traps and quadrats located beneath the crown of the roosting tree than in those located beyond the crown. With the exception of Cinnamomum subavenium, the seeds and seedlings of most diet species rarely survived beyond the first year. The quality of hornbill dispersal to this roosting site may be poor due to the highly concentrated seedfall, which results in high seed and seedling mortality. However, the number of seeds deposited by each hornbill each day at roosting sites is relatively low. Wreathed hornbills are primarily scatter dispersers during the day and probably serve as agents of seed dispersal in the moist evergreen forest of Khao Yai. [ABSTRACT FROM AUTHOR]

Natural seed deposition patterns and their effects on post-dispersal seed fate are critical to tropical tree recruitment. The major dispersal agents of the large-seeded tree Canarium euphyllum in Khao Yai National Park, Thailand, are large frugivorous birds such as hornbills, which generated spatially heterogeneous seed deposition patterns because they regurgitated seeds at perching trees and conspecific and heterospecific feeding trees. We investigated the fate of seeds dispersed in this manner using seed removal experiments and automatic camera trapping. Seeds placed experimentally around conspecific feeding trees had higher removal rates than seeds placed elsewhere. These effects were likely mediated by two seed-eating rodents, the Indochinese ground squirrel ( Menetes berdmorei) and the giant long-tailed rat ( Leopoldamys sabanus). Consequently, the spatial patterns generated by hornbills had consequences for post-dispersal seed fates, particularly whether or not the seeds were removed by rodents. Primary dispersal by hornbills does alter seed fate by altering the probability of rodent–seed interaction, but the ultimate impact of dispersal by hornbills will depend on how important rodent scatterhoarding is to seed germination and seedlings. Given that major seed dispersers of C. euphyllum are now absent or rare in degraded forests in tropical Asia, it is becoming increasingly important to understand the roles of scatterhoarding rodents in these altered habitats in this region. [ABSTRACT FROM AUTHOR]

While many tropical countries are experiencing rapid deforestation, some have experienced forest transition (FT) from net deforestation to net reforestation. Numerous studies have identified causative factors of FT, among which forest scarcity has been considered as a prerequisite for FT. In fact, in SE Asia, the Philippines, Thailand and Viet Nam, which experienced FT since 1990, exhibited a lower remaining forest area (30±8%) than the other five countries (68±6%, Cambodia, Indonesia, Laos, Malaysia, and Myanmar) where forest loss continues. In this study, we examined 1) the factors associated with forest scarcity, 2) the proximate and/or underlying factors that have driven forest area change, and 3) whether causative factors changed across FT phases (from deforestation to net forest gain) during 1980–2010 in the eight SE Asian countries. We used production of wood, food, and export-oriented food commodities as proximate causes and demographic, social, economic and environmental factors, as well as land-use efficiency, and wood and food trade as underlying causes that affect forest area change. Remaining forest area in 1990 was negatively correlated with population density and potential land area of lowland forests, while positively correlated with per capita wood production. This implies that countries rich in accessible and productive forests, and higher population pressures are the ones that have experienced forest scarcity, and eventually FT. Food production and agricultural input were negatively and positively correlated, respectively, with forest area change during 1980–2009. This indicates that more food production drives deforestation, but higher efficiency of agriculture is correlated with forest gain. We also found a U-shaped response of forest area change to social openness, suggesting that forest gain can be achieved in both open and closed countries, but deforestation might be accelerated in countries undergoing societal transition. These results indicate the importance of environmental, agricultural and social variables on forest area dynamics, and have important implications for predicting future tropical forest change. [ABSTRACT FROM AUTHOR]

The behaviour of wild cats is poorly understood. Using camera-trapping, we quantifi ed temporal overlap among seven species of Asian wild cats, including tiger Panthera tigris and leopard Panthera pardus. Based on time stamp data from 780 camera-traps and 24 study sites from 14 protected areas across Thailand, we assessed terrestrial activity patterns and temporal overlap in habitat use. For quantifying overlap, we used a coeffi cient estimator that allows for calculation of confi dence intervals. Our study provided insight into temporal interactions among species of wild cats, particularly between small cats and their larger cat relatives. We found temporal habitat segregation in several small cats with some species being strongly nocturnal (=85% records between 1800 and 0600 hours - leopard cat Prionailurus bengalensis), mostly (>50%) nocturnal (clouded leopard Neofelis nebulosa), mostly diurnal (>50% records between 0600 and 1800 hours - Asiatic golden cat Catopuma temminckii), or strongly (=85%) diurnal (marbled cat Pardofelis marmorata). We found high temporal overlap (Δ1 = 0.80) between leopard cat and clouded leopard (95% CI = 0.77-0.91), Asiatic golden cat and leopard (95% CI = 0.69-0.87), Asiatic golden cat and tiger (95% CI = 0.72-0.90), and clouded leopard and tiger (95% CI = 0.69-0.85). Our research demonstrates that temporal habitat or niche segregation may be an important process in maintaining the functioning of diverse predator guilds in tropical forests. We developed several avoidance or overlap hypotheses that can explain the patterns observed in our study and that should be further tested. [ABSTRACT FROM AUTHOR]

Southeast Asia's tropical forests suffer the highest rates of deforestation and disturbance of any on Earth, with poorly understood impacts on native fauna. Asian tapirs ( Tapirus indicus) are among the least studied of the large mammals in these forests. Using records from 9 camera trap surveys in 7 of the largest (>1000 km2) protected area complexes, we assessed the influence of environmental variation and human-induced disturbance on tapir occurrence. Tapirs were detected at 13% of locations sampled, significantly associated with evergreen forest ( P < 0.001). A multiple logistic regression model predicted tapir presence 87% of the time. According to this model, tapir occurrence was positively influenced by annual rainfall and proximity to the forest edge. However, tapirs may not avoid edges but instead prefer wetter evergreen forest, a habitat type that tended to occur further from the forest edge at higher elevations in our particular study sites ( P < 0.001). By comparison, 4 other wild ungulate species that share habitats with tapirs showed a range of differing responses. Tapirs are expected to be less sensitive to disturbance because they are not targets for hunting and trade, and are almost entirely active at night, so avoid peak traffic periods in parks. Tapir populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased >40% over the past 20 years. We recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas, research to better understand the fine-scale environmental influences on behavior and habitats of tapirs, and other forest ungulates, and continued legal status for tapirs in the highest category of protection. [ABSTRACT FROM AUTHOR]