Feeding Roosts Research Articles

The role of feeding roosts in seed dispersal service bats provide in urban areas

AbstractIn urban ecosystems, bats play an essential role in seed dispersal, which is facilitated by their use of feeding roosts. However, there are several knowledge gaps in this ecosystem service that bats provide in urban areas. We aimed to describe the fruits consumed by bats in an urban area, the selection and use of feeding roosts, and the patterns of seed dispersal by fruit bats in a Brazilian city. We collected and identified the seeds deposited under feeding roosts and tested for differences in the size of the seed of fruits consumed by bats and the seeds of fruits available in the study area. We also captured and identified bats feeding near roosts using mist nets and assessed the vegetation structure and urban variables that might influence the bats' tree choice for roosts. We found that Artibeus lituratus, Artibeus planirostris, and Platyrrhinus lineatus potentially used feeding roosts and preferred the tallest trees, which were located further away from artificial light. The average distance of seed dispersal was 105.5 meters, and the average size of the dispersed seeds did not differ from the seeds of the fruits available in the area, suggesting that bats are not limited to dispersing only tiny seeds. However, the prevalence of exotic seeds raises concerns that bats may spread exotic species, especially in surrounding protected areas. These results highlight the importance of frugivorous bats as significant seed dispersers in urban areas and emphasize the need for further research to understand their role in shaping urban ecosystems.Abstract in Portuguese is available with online material.

IMPACT OF FRUIT BATS (Rousettus leschenaulti AND Cynopterus sphinx) IN THE TROPICAL ECOSYSTEM OF TIRUNELVELI DISTRICT, TAMIL NADU, INDIA

Fruit bat diversity available in the ecosystem of Tirunelveli District is important for pollinating flowers and seed dispersal. Two common megachiropterans Rousettus leschnaulti (fulvous fruit bat) and Cynopterus sphinx (greater short-nosed fruit bat) interacting in different agro and tropical forest ecosystem of Tirunelveli district has been selected as study animals for this impact analysis. Various food selections, processing strategies, the economical and ecological importance of bat dependent plants have provided a glimpse on the fruit bat’s bio-agent role in the ecosystem. Identification of left outs from the feeding roosts, observations with video recording and mist-netting in the foraging areas is the documented data for fruit bat–plant interdependence. Their species specific dietary preferences immensely help to retain the community structures and long time survival of specific taxa in the ecosystem. In spite of their special role they have attracted little recognition under Indian government legislations and policies. The documented species specific impact and ecosystem services of R. leschnaulti and C. sphinx in the Tropical ecosystem is the field proof data which can be of use to revise the status of fruit bats under Schedule V, Indian Wildlife Protection Act 1972.

Frugivorous bats promote epizoochoric seed dispersal and seedling survival in a disturbed Neotropical forest

Abstract Animal-dispersed plants usually rely upon multiple dispersers. In many ecosystems, most of these interactions have yet to be explored; thus, documenting the extent of contribution of each animal partner to the reproduction and survival of plant species is key to understanding the ecology and evolution of animal–plant mutualism, as well as the potential responses of the ecological networks to biodiversity loss through defaunation. Here, by characterizing the outcomes and differences of the epizoochoric seed dispersal carried out by two species of frugivorous bats (Artibeus phaeotis and Uroderma convexum) in a Neotropical forest, we tested the prediction that, through their feeding activity, both bat species disperse and influence the subsequent seedling survival of multiple seed species. By direct sampling on bats’ dispersing sites and surrounding areas, we found evidence of the dispersal of 2,310 seeds of eight plant species, of which 118 survived to become seedlings. The total density of seeds and the seedling survival were significantly higher in areas directly influenced by the bats (i.e., feeding roosts) than in peripheral areas. Positive density-dependent effects nevertheless were detected in both sampling areas (feeding roosts and peripheral areas). Interspecific comparisons showed that despite both bat species having similar dispersal outcomes, seedlings in peripheral areas related to A. phaeotis have better survival rates. Our results demonstrate that both bat species primarily disperse by epizoochoric means seeds of various tree species at several localities in the study site. This result, together with the positive density-dependent effects, suggests that bats are moving seeds away from maternal trees and depositing them in locations where some of the seeds can germinate, establish, and survive, thereby highlighting the positive contribution of these bat species to the reproductive success of trees inhabiting Neotropical habitats. Our results contribute to the growing knowledge of frugivorous interactions on hyperdiverse forests and the role of small vertebrates on seed dispersal mutualisms.

Fruit bats in flight: a look into the movements of the ecologically important Eidolon helvum in Tanzania

BackgroundMany ecologically important plants are pollinated or have their seeds dispersed by fruit bats, including the widely distributed African straw-colored fruit bats (Eidolon helvum). Their ability to fly long distances makes them essential for connecting plant populations across fragmented landscapes. While bats have been implicated as a reservoir of infectious diseases, their role in disease transmission to humans is not well understood. In this pilot study, we tracked E. helvum to shed light on their movement patterns in Tanzania and possible contact with other species.MethodsTracking devices were deployed on 25 bats captured in the Morogoro Municipal and Kilombero District area near the Udzungwa Mountains of Tanzania. Nightly flight patterns, areas corresponding to foraging bouts and feeding roosts, and new day roosts were determined from bat movement data and characterized according to their proximity to urban built-up and protected areas. Sites for additional environmental surveillance using camera traps were identified via tracking data to determine species coming in contact with fruits discarded by bats.ResultsTracking data revealed variability between individual bat movements and a fidelity to foraging areas. Bats were tracked from one to six nights, with a mean cumulative nightly flight distance of 26.14 km (min: 0.33, max: 97.57) based on data from high-resolution GPS tags. While the majority of their foraging locations were in or near urban areas, bats also foraged in protected areas, of which the Udzungwa Mountains National Park was the most frequented. Camera traps in fruit orchards frequented by tracked bats showed the presence of multiple species of wildlife, with vervet monkeys (Chlorocebus pygerythrus) observed as directly handling and eating fruit discarded by bats.ConclusionsBecause we observed multiple interactions of animals with fruits discarded by bats, specifically with vervet monkeys, the possibility of disease spillover risk exists via this indirect pathway. With flight distances of up to 97 km, however, the role of E. helvum in the seed dispersal of plants across both protected and urban built-up areas in Tanzania may be even more important, especially by helping connect increasingly fragmented landscapes during this Anthropocene epoch.

Dispersal patterns of large-seeded plants and the foraging behaviour of a frugivorous bat

AbstractMutualistic interactions are biologically important, diverse and poorly understood. Comprehending these interactions and the effectiveness of the mutualistic partners has been the central focus of ecological and evolutionary studies, as this task requires disentangling the pieces of mutualism under study. Here, we tested the hypothesis that feeding activity of Artibeus phaeotis influences density, diversity and distance effects of the seed rain of large-seeded plant species in a Neotropical dry forest of Costa Rica. We predicted that bats’ activity increases density and diversity metrics on dispersing sites and that bats behave as short-distance dispersers. Our data revealed that, by dispersing hundreds of seeds within their small foraging areas and mostly close to fruiting trees, the feeding activity of A. phaeotis increases the density and richness of seeds underneath night feeding roosts. The functional role of A. phaeotis as disperser may vary among plant species, as we also detected that some seeds are more dispersed than others. Further inquiries to elucidate mutualistic interactions between frugivorous bats and large-seeded plant species should focus on understanding demographic and fitness outcomes, as strong selective pressures may be shaping morphological and behavioural traits of both plants and animals, ultimately influencing the survival of each partner.

Resolving the paradox of clumped seed dispersal: positive density and distance dependence in a bat‐dispersed species

One of the hypothesized benefits of seed dispersal is to escape density- and distance-responsive, host-specific, natural enemies near maternal plants where conspecific seed and seedling densities are high. Such high conspecific neighbor densities typically result in lower offspring growth and survival (i.e., negative density-dependent effects), yet many dispersal modes result in clumped seed distributions. New World leaf-nosed bats transport fruits to their feeding roosts and deposit seeds, thereby creating high-density seed/seedling patches beneath feeding roosts in heterospecific trees away from maternal trees, which seemingly nullifies a key benefit of seed dispersal. Such dispersal may still be adaptive if negative density-dependent effects are reduced under feeding roosts or if the benefit of being dispersed away from maternal trees outweighs negative effects of conspecific seed/seedling density below roosts. We mapped the entire post-germination population of a bat-dispersed tree species Calophyllum longifolium (Calophyllaceae) in a 50-ha plot on Barro Colorado Island, Panama in each of three successive years. We tested two hypotheses: (1) distance-dependent effects are stronger than density-dependent effects on seedling performance because seedlings far from conspecific adults are more likely to escape natural enemies even when at high densities and (2) negative density-dependent effects will be reduced far from vs. near conspecific adults. Density and distance were naturally decoupled, as expected. However, in contrast to our expectation, we found positive density effects on seedling survival and density-dependent effects did not differ with distance from conspecific adults. Both density and distance had positive effects on seedling survival when considered together, while only year had a significant effect on seedling growth. Thus, both being dispersed under bat feeding roosts and escaping the vicinity of conspecific adults were beneficial for C.longifolium seedling survival, supporting the directed dispersal and escape hypotheses, respectively. Despite resulting in high densities of conspecific seedlings, favorable habitat under bat feeding roosts and lack of negative density-dependent effects appear to provide evolutionary advantages in C.longifolium.

Dietary Composition of Four Common Chiropteran Species in a Bottomland Hardwood Forest

Understanding foraging habits can be important for elucidating the ecology of any species and for designing appropriate conservation strategies. Common methods for determining bat diets, such as morphological examination of fecal material or recovery of prey fragments under feeding roosts, can be biased towards larger prey with harder exoskeletons by underestimating frequency/occurrence of smaller, softer bodied prey items. Our objectives were to determine prey selection for several common chiropteran species of bottomland hardwood forests in east Texas and to evaluate the use of DNA barcoding for dietary studies by comparing dietary composition to prey availability in four species of bats. We amplified the cytochrome coxidase subunit 1 gene from fecal samples collected from 19 bats of four species and identified arthropods by comparison to the Barcode of Life Data System database. We compared frequency of occurrence in fecal samples to frequency in concurrent night-flying insect sampling. We identified nine insect species from three orders consumed by Perimyotis subflavus, nine species from four orders consumed by Lasiurus seminolus, seven species from three orders consumed by Nycticeius humeralis, and 11 species from two orders consumed by Lasiurus borealis. Coleoptera was the most abundant order available by biomass, but beetles were never found in fecal samples from L. seminolus (n = 5) or L. borealis (n = 7) bats. However, Coleoptera comprised a substantial portion of prey identified from P. subflavus (n = 2) and N. humeralis samples (n = 5). Lepidopteran prey items were found in 13 of 19 bat fecal samples across all species but represented < 7% of arthropod biomass. Although dipteran species were a negligible portion (< 1%) of the available biomass, large numbers of dipterans were identified in fecal samples from all species of bats (13 of 19 samples across all species). Lasiurus seminolus and L. borealis may be selecting prey based on digestibility rather than availability; whereas, both N. humeralis and P. subflavus exhibited a more opportunistic approach to foraging. Based on comparison to other studies of bat diets, traditional techniques for analyzing diet from fecal samples are likely underrepresenting soft-bodied arthropods like dipterans.

Seed dispersal of a tropical deciduous Mahua tree, Madhuca latifolia (Sapotaceae) exhibiting bat-fruit syndrome by pteropodid bats

Pollination and seed dispersal are two important phases of the reproductive cycle in plants and are usually performed by different groups of animal taxa in tropics. However, in Mahua tree, Madhuca latifolia (Sapotaceae) both pollination and seed dispersal are predominantly performed by pteropodid bats. We report the foraging and seed dispersal strategies of three sympatric pteropodid bats, Cynopterus sphinx, Rousettus leschenaultii and Pteropus giganteus, during two successive fruiting seasons of M. latifolia. These sympatric fruit bats exhibited spatio-temporal variation while foraging and consumed fleshy mesocarp of fruits and discarded the seeds. Fruit processing time corresponded to the size of the bat species (P. giganteus > R. leschenaultii > C. sphinx); the larger the bat, the more number of fruits they consumed. P. giganteus predominantly consumed the fruits in situ (87% of the times). However, during peak foraging hours, when intraspecific aggressive interactions were high, these bats flew away with fruits from the parent tree (13%), and transported seeds to longer distances (at a time, which they carried = 7.2 km). On the contrary, R. leschenaultii and C. sphinx plucked one fruit at a time and carried to their feeding roosts for consumption. The feeding roosts of medium-sized fruit bat R. leschenaultii were located farther than that of the small-sized C. sphinx, i.e., 52.81 m and 34.18 m, respectively. Comparison of seed germination rates showed no significant variation between bat-dispersed seeds (R. leschenaultii: 95% and C. sphinx: 90%) and control seeds (manually extracted: 90%). As intact fruits did not germinate, mesocarp removal and mobility of seeds away from the parent tree were the main advantages gained by M. latifolia from the foraging bats suggesting the existence of a resource−service mutualism between the fruit bats and bat fruits.

Effect of female group size on harem male roosting behavior of the Indian short-nosed fruit bat Cynopterus sphinx

Mate guarding has been known to incur costs and cause constraints for harem males in many polygynous species. However, the effect of female group size on the harem male’s time budget in bats has received very limited attention. The Indian short-nosed fruit bat, Cynopterus sphinx, exhibits resource defense polygyny, in which tent roosting males construct tents and defend multiple female bats. We studied the effect of female group size on three aspects of harem male behavior: social grooming by reciprocal licking, tent maintenance, and tent guarding in the mast tree Polyalthia longifolia. In the process of reciprocal licking, all the bats in the harem were drenched in saliva before emergence, and this activity was positively and significantly correlated with female group size. Once females departed for foraging, harem males remained in their respective tents at night-time between intermittent foraging bouts and engaged in tent maintenance and tent guarding. Time invested by harem male bats in tent maintenance and tent guarding were positively and significantly correlated with female group size. Harem males extended their presence in tent by utilizing tents as feeding roosts. Female group size also influenced the emergence time of harem male bats, where males with largest group emerged later than did the smallest group. Likewise, harem male with the smallest group had more time available for foraging than the male with the largest group. Findings of this study suggest that having a larger harem may indeed be costly for the males by reducing their foraging time.

Long-distance seed dispersal by straw-coloured fruit bats varies by season and landscape

On-going fragmentation of tropical forest ecosystems and associated depletion of seed dispersers threatens the long-term survival of animal-dispersed plants. These threats do not only affect biodiversity and species abundance, but ultimately ecosystem functions and services. Thus, seed dispersers such as the straw-coloured fruit bat, E. helvum, which traverse long distances across fragmented landscapes, are particularly important for maintaining genetic connectivity and colonizing new sites for plant species. Using high-resolution GPS-tracking of movements, field observations and gut retention experiments, we quantify dispersal distances for small- and large-seeded fruits foraged by E. helvum during periods of colony population low (wet season) and high (dry season) in an urban and a rural landscape in the forest zone of Ghana. Gut passage time averaged 116 min (range 4–1143 min), comparable to other fruit bats. Movements were generally longer in the urban than in the rural landscape and also longer in the dry than in the wet season. As the majority of seeds are dispersed only to feeding roosts, median dispersal distances were similar for both large (42–67 m) and small (42–65 m) seeds. However, small seeds were potentially dispersed up to 75.4 km, four times further than the previous maximum distance estimated for a similar-sized frugivore. Maximum seed dispersal distances for small seeds were almost twice as long in the rural (49.7 km) compare to the urban (31.2 km) landscape. Within the urban landscape, estimated maximum dispersal distances for small seeds were three times longer during the dry season (75.4 km) compared to the wet season (22.8 km); in contrast, distances in the rural landscape were three times longer in the wet season (67 km) compared to the dry season (24.4). Dispersal distances for large seeds during the dry season (551 m) in the rural landscape were almost twice that in the wet season (319 m). We found no influence of food phenology on dispersal distances. The maximum likelihood for seed dispersal beyond feeding roosts (mean distance from food tree 263 m) was 4.7%. Small seeds were dispersed over even longer distances, >500 and >1000 m, with a likelihood of 3.0 % and 2.3 % respectively. Our data show that E. helvum retains ingested seeds for very long periods and may traverse large distances, probably making it an important long distance seed disperser in tropical Africa. We suggest E. helvumis important for ecosystem functioning and urge its conservation.

Seed rain generated by bats under Cerrado's pasture remnant trees in a Neotropical savanna.

In this study we described the seed rain generated by bats under four Cerrado's tree species common within pastures, Buchenavia tomentosa, Couepia grandiflora, Licania humilis and Qualea grandiflora. We analyzed the similarity among the four tree species in terms of seed rain composition, and compared the number of seeds and seed species deposited under them. Besides that, we assessed the relationship between seed rain intensity and the density of each tree species. Then, we randomly selected 10 mature trees of each species to sample seed rain. We recorded a total of 4892 bat dispersed seeds from 11 species. Also, we observed that along the year seed deposition varied substantially under all trees. At least two seed sub-communities could be distinguished according to tree species used by bats as feeding roost. One related to Couepia grandiflora and Licania humilis, and the other to Buchenavia tomentosa and Qualea grandiflora trees. The variability of seed rain composition in any particular tree and the range of actual seed fall into a particular species indicate patchiness in seed rain, and the overall results appear to be consistent in terms of a substantial and diverse seed rain generated by bats in a highly anthropized landscape. This is the first study concerning seed dispersal by bats in modified Brazilian Cerrado, one of the most endangered biomes in the world. In this respect, by preserving a dense and diverse collection of remnant trees within today's pastures may, potentially, contribute to a faster Cerrado recovery in extensive areas that can be reclaimed for restoration in the future.

Geophagy by the Indian short-nosed fruit bat, Cynopterus sphinx (Pteropodidae) while foraging on Madhuca latifolia (Sapotaceae) in Tamil Nadu, South India

Geophagy has been reported in many mammals and birds. However, in pteropodid bats, this behaviour has not been reported. Here, we document geophagy behaviour by the pteropodid bat, Cynopterus sphinx, during foraging in the fruiting trees of Madhuca latifolia (Sapotaceae). These bats removed single fruits from the foraging tree and carried it to the feeding roost for consumption. At around 1900 h, we observed three individuals of C. sphinx gleaning over the ground surface by circling flights. The bats landed with their wings spread apart and started licking the soil with head movements. Their ventral body surface rested completely on the ground while consuming the soil. A total of 91 feeding bouts of soil consumption were recorded within 1 h; however, thereafter, this behaviour was not observed. In order to understand the function of geophagy, we quantitatively analysed the composition of minerals in the soil, as well as in the M. latifolia fruits (partially ripe) along with its secondary metabolites from the study site. Our results revealed that the partially ripe fruits contained high levels of secondary metabolites (alkaloids, tannins, coumarins and saponins). The soil contained higher levels of Mg, Ca, Fe, Na and K minerals than the fruits. These findings suggest that bats may gain essential minerals that are low in their fruit diet by consuming soil. In addition, the observed minerals that play a role in detoxification of the secondary metabolites present in the partially ripe fruits that might be detrimental to the consuming bats. Frugivory, nectarivory and folivory are well understood in C. sphinx; however, geophagy behaviour has not been reported in this species so far. This may represent an ‘adaptive behavioural plasticity’ in the foraging behaviour of the observed C. sphinx population.

Seed Dispersal in the Dark: Shedding Light on the Role of Fruit Bats in Africa

AbstractIn spite of their recognized importance as seed dispersers in other parts of the tropics, seed dispersal by fruit bats has received scant research attention in Africa. To evaluate the role of African fruit bats in seed dispersal, we studied fruits and seeds below 480 bat feeding roosts in the East Usambara Mountains of Tanzania. We compared these findings to those reported in other African localities to place our results in a broader context. We found 49 plant species dispersed by bats: 28 species, 18 genera, and one family are novel reports of bat dispersal in Africa. Approximately 20 percent of the submontane tree flora of the East Usambaras is bat‐dispersed, including both widespread and endemic trees. African fruit bats are important seed dispersers at our study site because they move seeds of dozens of species tens or hundreds of meters, even seeds that are too large to ingest (greater than 5 mm in length). Fruit bats are likely important seed dispersers in other Afrotropical forests, as bats elsewhere in Africa are known to consume 20 genera and 16 species of plants reported here. Insights from studying remains under bat feeding roosts offer a simple method to further document and substantially increase our understanding of the role of African fruit bats in seed dispersal.

Diet of Tonatia bidens (Chiroptera, Phyllostomidae) in an Atlantic Forest area, southeastern Brazil: first evidence for frugivory

The greater round-eared bat Tonatia bidens has a varied diet, consuming mostly insects, although it also feeds on small terrestrial vertebrates, such as rodents and birds. In 2008–2009, we expanded the knowledge of this species’ feeding ecology by analyzing the diet of a T. bidens population in an Atlantic Forest fragment in southeastern Brazil. Food remains found in day shelters and feeding roosts included insects, birds, mammals and fruits. Insects, Lepidoptera, Blattodea, Coleoptera and Orthoptera, were the main component of the diet. There was a preferential consumption of the soft parts of insects and vertebrates, possibly because these parts are more easily digested and are the most nutritious. This first evidence of fruit consumption is also discussed. This analysis indicates that T. bidens has a more general diet than previously reported.

Seed dispersal ofSyzygium oblatum(Myrtaceae) by two species of fruit bat (Cynopterus sphinxandRousettus leschenaulti) in South-West China

Abstract:In this study we investigated the importance of two species of fruit bat (Rousettus leschenaultiandCynopterus sphinx) as seed dispersers for a species of fruit tree (Syzygium oblatum) found in the Xishuangbanna Tropical Botanical Garden in South-West China. We found that althoughR. leschenaultiandC. sphinxwere the two primary seed dispersers ofS. oblatumover half of the fruit produced by the tree (65%) fell to the ground. Out of the fruit collected,R. leschenaultiandC. sphinxwere able to disperse seeds up to 73 m from the parent tree with the highest density of feeding roosts occurring at 21.3 m (SE = 5.2 m). We found no signs that either species of bat used the parent tree as a feeding roost, instead choosing specific trees that were at lower densities compared with other trees in the forest that were not used. When comparing the viability of seeds in three different habitats (under parent tree, in forest gap, under feeding roost) survival analysis revealed that seedling survival was significantly higher in the forest gap (91.7% ± 4.41%) than under the parent tree (78.3% ± 1.67%), but was not significantly different to seedling survival underneath feeding roosts (86.7 ± 1.67%). Further work also showed that the seeds did not have to be removed from the fruit or ingested by the bat in order to germinate. We conclude that althoughS. oblatumis not dependent onR.leschenaultiandC. sphinxfor successful germination of its seeds, these two species of bat are important seed dispersers and can move seeds to areas where there is a greater chance of germination success and survival.

Wahlberg’s epauletted fruit bat (Epomophorus wahlbergi) as a potential dispersal agent for fleshy-fruited invasive alien plants: effects of handling behaviour on seed germination

The spread of invasive alien plants into natural habitats is of growing global concern. Several studies have investigated the role that avian frugivores play in the dispersal of these seeds and their effects on germination success. Fruit bats have however received little attention as important dispersal agents of invasive alien plants, despite their recognized role as long distance dispersal agents of various native flora. We investigated whether Wahlberg’s epauletted fruit bats, Epomophorus wahlbergi, would positively influence the germination of seeds of invasive alien plants. These fruit bats were fed fruits of four invasive alien plant species—Psidium guajava, Melia azedarach, Eriobotrya japonica, and Morus alba. Epomophorus wahlbergi were able to process more fruit per gram body mass than birds have been observed to do. Spat and de-pulped control seeds had similar germination success and germinated at approximately the same time for most species. While seeds retained in whole fruit had significantly less germination success than spat seeds for all species, except M. azedarach, they mostly germinated at approximately the same time. Epomophorus wahlbergi can swallow small seeds (< 2 mm), while seeds larger than this are generally spat out. Large fruit are usually carried away to feeding roosts where seeds are dropped, thereby dispersing seeds and fruits which are too large for some bird species to ingest. Epomophorus wahlbergi should not be underestimated as dispersers of these invasive alien plants as they consume proportionally large amounts (0.62 ± 0.09 to 0.99 ± 0.11 g.g−1 body mass) of fruit, except for M. azedarach, and positively affect their seed germination rates.

Colony size, sex ratio and cohabitation in roosts of Phyllostomus hastatus (Pallas) (Chiroptera: Phyllostomidae)

Phyllostomus hastatus bat is species broadly distributed over the Neotropical region, which uses as diurnal roosts caves, hollow trees, palm leaves and human buildings. Thirteen diurnal roosts of P. hastatus were analysed from 1990 to 2009 in several localities of Rio de Janeiro State, regarding environment (rural, urban or protected area), type of roost (hollow tree, basement or roof), sex ratio and cohabitation. A nocturnal roost was also analysed. Sex ratio of P. hastatus varied considerably among roosts what may be explained by the fact this species can roost alone, in couples, in harems or in groups of bachelor males. Phyllostomus hastatus was observed in cohabitation with three other species: Molossus rufus, Molossus molossus and Myotis nigricans. Due to the frequency of cohabitation observed between P. hastatus and species of the genus Molossus, one or more advantages for the members of this association may be expected. The simultaneous usage of a feeding roost by a group of bachelor males is unknown information in the literature, and may suggest that this kind of group may interact with each other even when away from their diurnal roosts.

Bat Foraging Strategies and Pollination ofMadhuca latifolia(Sapotaceae) in Southern India

The sympatrically occurring Indian short-nosed fruit bat Cynopterus sphinx and Indian flying fox Pteropus giganteus visit Madhuca latifolia (Sapotaceae), which offers fleshy corollas (≈ 300 mg) to pollinating bats. The flowers are white, tiny and in dense fascicles. The foraging activities of the two bat species were segregated in space and time. Cynopterus sphinx fed on resources at lower heights in the trees than P. giganteus and its peak foraging activity occurred at 19:30 h, before that of P. giganteus. Foraging activities involved short searching flights followed by landing and removal of the corolla by mouth. Cynopterus sphinx detached single corollas from fascicles and carried them to nearby feeding roosts, where it sucked the juice and spat out the fibrous remains. Pteropus giganteus landed on top of the trees and fed on the corollas in situ; its peak activity occurred at 20:30 h. This species glided and crawled between the branches and held the branches with claws and forearms when removing fleshy corollas with its mouth. Both C. sphinx and P. giganteus consumed fleshy corollas with attached stamens and left the gynoecium intact. Bagging experiments showed that fruit-set in bat-visited flowers was significantly higher (P < 0.001) than in self-pollinated flowers.

Small Tent‐Roosting Bats Promote Dispersal of Large‐Seeded Plants in a Neotropical Forest

ABSTRACTIn Neotropical regions, fruit bats are among the most important components of the remaining fauna in disturbed landscapes. These relatively small‐bodied bats are well‐known dispersal agents for many small‐seeded plant species, but are assumed to play a negligible role in the dispersal of large‐seeded plants. We investigated the importance of the small tent‐roosting bat Artibeus watsoni for dispersal of large seeds in the Sarapiquí Basin, Costa Rica. We registered at least 43 seed species &gt; 8 mm beneath bat roosts, but a species accumulation curve suggests that this number would increase with further sampling. Samples collected beneath bat feeding roosts had, on average, 10 times more seeds and species than samples collected 5 m away from bat feeding roosts. This difference was generally smaller in small, disturbed forest patches. Species‐specific abundance of seeds found beneath bat roosts was positively correlated with abundance of seedlings, suggesting that bat dispersal may influence seedling recruitment. Our study demonstrates a greater role of small frugivorous bats as dispersers of large seeds than previously thought, particularly in regions where populations of large‐bodied seed dispersers have been reduced or extirpated by hunting.

The role of Orii's flying‐fox (Pteropus dasymallus inopinatus) as a pollinator and a seed disperser on Okinawa‐jima Island, the Ryukyu Archipelago, Japan

AbstractThe role of the Orii's flying‐fox (Pteropus dasymallus inopinatus) as a pollinator and a seed disperser on Okinawa‐jima Island was investigated by direct observations and radio‐tracking from October 2001 until January 2006. We found that Orii's flying‐fox potentially pollinated seven native plant species. Its feeding behavior and plant morphological traits suggested that this species is an important pollinator of Schima wallichii liukiuensis and Mucuna macrocarpa. The flying‐fox also dispersed the seeds of 20 native plant species. The seeds of all plants eaten by the flying‐fox were usually dropped beneath the parent tree, although large fruits of four plant species were occasionally brought to the feeding roosts in the mouth, with the maximum dispersal distance—for Terminalia catappa—estimated to be 126 m. Small seeds of 11 species (mostly Ficus species) were dispersed around other trees, during the subsequent feeding session, through the digestive tracts, with the mean dispersal distance for ingested seeds estimated at 150 ± 230.3 m (±SD); the maximum dispersal distance was 1833 m. A comparison of the seed dispersal of available fruits according to the size of flying‐foxes and other frugivores suggested that the seed dispersal of eight plant species producing large fruits mostly depended on Orii's flying‐fox. On Okinawa‐jima Island, the Orii's flying‐fox plays an important role as a pollinator of two native plants and as a long‐distance seed disperser of Ficus species, and it functions as a limited agent of seed dispersal for plants producing large fruits on Okinawa‐jima Island.