Fruit Bats (Chiroptera: Pteropodidae) as Seed Dispersers and Pollinators in a Lowland Malaysian Rain Forest1

The aims of this study were to (1) characterize the food resources exploited by fruit bats (Pteropodidae) within an old‐growth Malaysian dipterocarp forest, (2) test the viability of the seeds they disperse, and (3) provide an estimate of the proportion of trees that are to some degree dependent upon bats for seed dispersal and/or pollination. Fruit species exploited by bats could be distinguished from those eaten by birds largely on the basis of color (as perceived by human beings). Bat‐dispersed fruits were typically inconspicuous shades of green–yellow or dull red–brown, whereas fruits eaten by birds were generally bright orange to red. Dietary overlap between bats and nonflying mammals was relatively high. In contrast to primates and squirrels, which were major seed predators for several of the plant species under investigation, fruit bats had no negative impact on seed viability. A botanical survey in 1 ha of old‐growth forest revealed that 13.7 percent of trees (?15 cm girth at breast height) were at least partially dependent upon fruit bats for pollination and/or seed dispersal.     

Bat activity and species richness in different land‐use types in and around Chome Nature Forest Reserve,Tanzania

Bats have important ecological roles in ecosystems, but many species are threatened because of anthropogenic impacts. Tanzania has limited information on how bats respond to habitat modification. This makes it difficult to anticipate which bat species are at risk. Bat activity and species richness were assessed in five land‐use types: forest and banana–coffee (upland habitats), rice paddy, riverine and sisal estate (lowland habitats). Mist nets, harp traps and bat detectors were used to sample bats. Species richness differed between habitats. Bat activity levels were higher in lowland habitats than upland habitats. Riverine and rice paddy habitats were shown to have an important role as foraging sites for many insectivorous bats as bat species richness and activity were generally higher than other habitats. Fruit‐eating bats preferred riverine and banana–coffee habitats. We recommend using organic manure as alternatives to chemical fertilisers, and pesticide use should be avoided in rice paddies. Riparian vegetation along rivers and water bodies should be maintained as important faunal nesting, roosting and/or foraging grounds. The requirement that farming practices be at least 60 m from the river should be strictly enforced. These recommendations will help in the conservation of bats and their habitats in modified agricultural landscapes.     

Impact of external odor on self‐grooming of lesser flat‐headed bats,Tylonycteris pachypus

Grooming is a common behavior of some mammals. Previous studies have shown that grooming is a means by which animals clean themselves, remove ectoparasites, and lower their body temperature. It is also involved in olfactory communication. Bats belong to the order Chiroptera and, like most mammals, are the natural host of many ectoparasites. Bat grooming, including licking and scratching, is one of the ways to reduce the adverse effects caused by ectoparasites. Bat grooming may also be induced by exogenous odor. In this study, we used lesser flat‐headed bats (Tylonycteris pachypus) to test the hypothesis that exogenous odor affects the self‐grooming behavior of bats. Results showed that external odor from distantly related species caused lesser flat‐headed bats to spend more time in self‐grooming. Lesser flat‐headed bats that received odor from humans spent the longest time in self‐grooming, followed by those that received odor from a different species of bats (T. robustula). Lesser flat‐headed bats that received odor form the same species of bats, either from the same or a different colony, spent the least amount of time in self‐grooming. These results suggest that bats can recognize conspecific and heterospecific through body scent.     

Bartonella species in bat flies (Diptera: Nycteribiidae) from western Africa

Bat flies are obligate ectoparasites of bats and it has been hypothesized that they may be involved in the transmission of Bartonella species between bats. A survey was conducted to identify whether Cyclopodia greefi greefi (Diptera: Nycteribiidae) collected from Ghana and 2 islands in the Gulf of Guinea harbour Bartonella. In total, 137 adult flies removed from Eidolon helvum, the straw-coloured fruit bat, were screened for the presence of Bartonella by culture and PCR analysis. Bartonella DNA was detected in 91 (66·4%) of the specimens examined and 1 strain of a Bartonella sp., initially identified in E. helvum blood from Kenya, was obtained from a bat fly collected in Ghana. This is the first study, to our knowledge, to report the identification and isolation of Bartonella in bat flies from western Africa.     

A comparison of two bat detectors: which is most likely to detect New Zealand’s Chalinolobus tuberculatus?

ABSTRACT

The presence of bat species is commonly determined by placing acoustic bat detectors that record bat echolocation calls in the habitat they are likely to use. Detection rates are affected by variables including type of detection unit used. We compared detection rates of long-tailed bat (Chalinolobus tuberculatus) echolocation calls between two types of automated bat detectors: Wildlife Acoustics SMZC Zero Crossing Bat Recorders (ZC), and Frequency Compression Automated Bat Monitoring units (FC) produced by New Zealand’s Department of Conservation. Units were placed in locations where bats were known to be present, but not all detected bats. The median number of bat passes recorded by FC units over 10 nights was 20 compared with a median of 3 bat passes for ZC units. ZC units also detected bats over significantly fewer nights than FC units. These results suggest FC units are more sensitive and therefore better to use where long-tailed bats are expected to be at low abundance or only present infrequently. Because of inconsistencies in detection rates, we recommend the use of only one model of the detector within a monitoring project. Our data also suggests that surveys should take place over long periods to maximise likelihood of detecting bats, if present.     

Activity patterns of insectivorous bats and birds in northern Scandinavia (69° N), during continuous midsummer daylight

Previous studies suggest that many species of insectivorous bats are nocturnal, despite the relatively low availability of their insect prey at night, because of the risk of predation by diurnal predatory birds. We hypothesised that if this was the case bats living above the arctic circle would alter their feeding behaviour during midsummer because there would no longer be any benefit to restricting their activity to the period when their prey are least abundant. Alternatively, if bats were more influenced by competition from aerial insectivorous birds they would continue to feed at 'night' to avoid such competition. In northern Norway (69°  N), during continuous midsummer daylight, insectivorous sand martins ( Riparia riparia ) concentrated their aerial feeding activity when aerial insects were most abundant. The birds stopped feeding between 23:00 and 07:00 when aerial insects were least abundant. In contrast, northern bats ( Eptesicus nilssonii ), fed mostly between 22:00 and 02:00, coinciding with the lowest aerial insect availability, and with the period when light levels were lowest (ca 1000 lux). Bat activity patterns were closest to those predicted by the avian competition hypothesis. The low densities of both sand martins and Northern bats in the study area, however, were less consistent with this hypothesis. Possibly populations of both species were higher historically and the observed patterns reflected historical competition. Bat activity was most closely correlated to ambient light levels. This raised two alternative explanations that we could not eliminate. Perhaps there was differential predation risk, between the brightest and darkest parts of the day, because the visual capacities of falcons are strongly dependent on luminance. Alternatively the bats may have been entrained to emerge at given light levels by their behaviour at other times of year.     

Changing attitudes to nature conservation: The National Trust

The National Trust was founded in 1895 to preserve land and its associated flora, fauna and buildings. The Trust's land holding has since increased to over 220000 ha, of which almost one-third is of high nature conservation value. The protection provided by Trust ownership is particularly important for certain species. In recent years land management for nature conservation has been transferred from volunteers to professional staff and links with other conservation bodies have been developed. A special programme began in 1979 to survey the wildlife of Trust properties. Research is encouraged where it will benefit management. In some areas where traditional management has lapsed the Trust has invested considerable resources into restoring former regimes.     

An analysis of Bat Hawk Macheiramphus alcinus diet in the Melaky Region of lowland western Madagascar

We present information on the prey taken by the Bat Hawk Macheiramphus alcinus in two different areas of lowland western central Madagascar. These are the first dietary data from Madagascar for this widespread Old World species. The recovered remains were almost exclusively of bats and birds, with a few examples of reptiles and insects. In total, 178 pellets were analysed. On the basis of minimum number of individuals and biomass, bats accounted for 58.3% and 30.3%, respectively, and birds 36.1% and 69.7%, respectively. Amongst the nine species of bats recovered from the pellets, four were represented by multiple individuals, particularly taxa belonging to the families Molossidae and Vespertilionidae that fly in open areas, and for the 11 species of identified birds, all were represented by a single individual. These patterns are interpreted as a specialisation of feeding on bats during a narrow window of time at dusk, as they leave day roost sites, and then using birds in a more general manner to fill in nutritional needs.     

Seasonal habitat selection and temporal activity patterns determine the structure of bat assemblages in Dhana Biosphere Reserve,Jordan (Mammalia: Chiroptera)

We measured species richness, diversity, and diel activity patterns of insectivorous bats at four sites within Dhana Biosphere Reserve. A total of seven species belonging to five families at varying species compositions were recorded. Four to six species were present at these sites and total diversity ranged between 0.32 at Ain Lahtha and 0.65 at Al Khararah. Overall frequency of passes was highest at Shaq Kalbeh. The Common Pipistrelle, Pipistrellus pipistrellus, was the most prevalent at three sites, followed by the Arabian Horseshoe Bat, Rhinolophus clivosus, and Botta’s Serotine, Eptesicus bottae. Natterer’s Bat, Myotis nattereri, and the European Free-tailed Bat, Tadarida teniotis, occurred at low abundance. The Lesser Horseshoe Bat, Rhinolophus hipposideros, occurred at a higher abundance within Finan site (arid site at lower altitude), whereas the Egyptian Mouse-tailed Bat, Rhinopoma cystops, was restricted to Finan. The overall mean number of bat passes was not significantly different between sites. Average seasonal species diversity was low during winter (none at Ain Lahtha and Shaq Kalbeh) and highest during summer (0.68 at Al Kharrarah). Seasonal activity patterns for each site in terms of frequencies of bat passes on an hourly basis are given.     

广东石门台国家级自然保护区蝙蝠多样性

本研究于2017至2019年对广东石门台国家级自然保护区的翼手目动物资源进行调查,调查方法主要为日栖息地与夜栖息地调查、网捕调查,共调查到翼手目动物4科9属31种。其中,菊头蝠科1属7种,占比22.6%,蹄蝠科1属4种,占比12.9%,假吸血蝠科1属1种,占比3.2%,蝙蝠科6属19种,占比61.3%。31种蝙蝠的区系组成以东洋型为主,共有19种,而南中国型和季风型较少,南中国型为7种,季风型为5种。以栖息类型划分,石门台保护区的翼手目动物可以分成3类,其中,洞栖型有12种,建筑物栖型有4种,树栖型有4种,另有8种蝙蝠的栖息地可包括洞穴和建筑物,3种的栖息地可包括建筑物和树洞。石门台保护区作为面积较大的国家级自然保护区,调查到蝙蝠种类31种,属于物种多样性较为丰富的保护区。本研究调查了石门台保护区的蝙蝠多样性数据,为以后深入探究该保护区的野生动物资源提供了基础资料。     

The evolution of bat pollination: a phylogenetic perspective

Background

Most tropical and subtropical plants are biotically pollinated, and insects are the major pollinators. A small but ecologically and economically important group of plants classified in 28 orders, 67 families and about 528 species of angiosperms are pollinated by nectar-feeding bats. From a phylogenetic perspective this is a derived pollination mode involving a relatively large and energetically expensive pollinator. Here its ecological and evolutionary consequences are explored.

Scope and Conclusions

This review summarizes adaptations in bats and plants that facilitate this interaction and discusses the evolution of bat pollination from a plant phylogenetic perspective. Two families of bats contain specialized flower visitors, one in the Old World and one in the New World. Adaptation to pollination by bats has evolved independently many times from a variety of ancestral conditions, including insect-, bird- and non-volant mammal-pollination. Bat pollination predominates in very few families but is relatively common in certain angiosperm subfamilies and tribes. We propose that flower-visiting bats provide two important benefits to plants: they deposit large amounts of pollen and a variety of pollen genotypes on plant stigmas and, compared with many other pollinators, they are long-distance pollen dispersers. Bat pollination tends to occur in plants that occur in low densities and in lineages producing large flowers. In highly fragmented tropical habitats, nectar bats play an important role in maintaining the genetic continuity of plant populations and thus have considerable conservation value.     

Bat Response to Differing Fire Severity in Mixed-Conifer Forest California,USA

Wildlife response to natural disturbances such as fire is of conservation concern to managers, policy makers, and scientists, yet information is scant beyond a few well-studied groups (e.g., birds, small mammals). We examined the effects of wildfire severity on bats, a taxon of high conservation concern, at both the stand (<1 ha) and landscape scale in response to the 2002 McNally fire in the Sierra Nevada region of California, USA. One year after fire, we conducted surveys of echolocation activity at 14 survey locations, stratified in riparian and upland habitat, in mixed-conifer forest habitats spanning three levels of burn severity: unburned, moderate, and high. Bat activity in burned areas was either equivalent or higher than in unburned stands for all six phonic groups measured, with four groups having significantly greater activity in at least one burn severity level. Evidence of differentiation between fire severities was observed with some Myotis species having higher levels of activity in stands of high-severity burn. Larger-bodied bats, typically adapted to more open habitat, showed no response to fire. We found differential use of riparian and upland habitats among the phonic groups, yet no interaction of habitat type by fire severity was found. Extent of high-severity fire damage in the landscape had no effect on activity of bats in unburned sites suggesting no landscape effect of fire on foraging site selection and emphasizing stand-scale conditions driving bat activity. Results from this fire in mixed-conifer forests of California suggest that bats are resilient to landscape-scale fire and that some species are preferentially selecting burned areas for foraging, perhaps facilitated by reduced clutter and increased post-fire availability of prey and roosts.     

A less-than-annual breeding cycle in a pair of African Bat Hawks Machaeramphus alcinus

This cycle differs from the known situation in rural Bat Hawks which lay annually mainly during September and October. These probably take advantage of easily-caught pregnant female bats in September/October in order to attain breeding condition, whereas fledgling Bat Hawks take advantage of recently independent but naive juvenile bats in January/February. The relative dearth of bats in rural areas outside this period may account for the regular annual breeding of Bat Hawks at the time of greatest prey availability.     

Hibernacula microclimate and declines in overwintering bats during an outbreak of white‐nose syndrome near the northern range limit of infection in North America

We document white‐nose syndrome (WNS), a lethal disease of bats caused by the fungus Pseudogymnoascus destructans (Pd), and hibernacula microclimate in New Brunswick, Canada. Our study area represents a more northern region than is common for hibernacula microclimate investigations, providing insight as to how WNS may impact bats at higher latitudes. To determine the impact of the March 2011 arrival of Pd in New Brunswick and the role of hibernacula microclimate on overwintering bat mortality, we surveyed bat numbers at hibernacula twice a year from 2009 to 2015. We also collected data from iButton temperature loggers deployed at all sites and data from HOBO temperature and humidity loggers at three sites. Bat species found in New Brunswick hibernacula include Myotis lucifugus (Little Brown Bat) and M. septentrionalis (Northern Long‐eared Bat), with small numbers of Perimyotis subflavus (Tricolored Bat). All known hibernacula in the province were Pd‐positive with WNS‐positive bats by winter 2013. A 99% decrease in the overwintering bat population in New Brunswick was observed between 2011 and 2015. We did not observe P. subflavus during surveys 2013–2015 and the species appears to be extirpated from these sites. Bats did not appear to choose hibernacula based on winter temperatures, but dark zone (zone where no light penetrates) winter temperatures did not differ among our study sites. Winter dark zone temperatures were warmer and less variable than entrance or above ground temperatures. We observed visible Pd growth on hibernating bats in New Brunswick during early winter surveys (November), even though hibernacula temperatures were colder than optimum for in vitro Pd growth. This suggests that cold hibernacula temperatures encountered near the apparent northern range limit for Pd do not sufficiently slow fungal growth to prevent the onset of WNS and associated bat mortality over the winter.     

Bat and bird diversity along independent gradients of latitude and tree composition in European forests

Species assemblages are shaped by local and continental-scale processes that are seldom investigated together, due to the lack of surveys along independent gradients of latitude and habitat types. Our study investigated changes in the effects of forest composition and structure on bat and bird diversity across Europe. We compared the taxonomic and functional diversity of bat and bird assemblages in 209 mature forest plots spread along gradients of forest composition and vertical structure, replicated in 6 regions spanning from the Mediterranean to the boreal biomes. Species richness and functional evenness of both bat and bird communities were affected by the interactions between latitude and forest composition and structure. Bat and bird species richness increased with broadleaved tree cover in temperate and especially in boreal regions but not in the Mediterranean where they increased with conifer abundance. Bat species richness was lower in forests with smaller trees and denser understorey only in northern regions. Bird species richness was not affected by forest structure. Bird functional evenness increased in younger and denser forests. Bat functional evenness was also influenced by interactions between latitude and understorey structure, increasing in temperate forests but decreasing in the Mediterranean. Covariation between bat and bird abundances also shifted across Europe, from negative in southern forests to positive in northern forests. Our results suggest that community assembly processes in bats and birds of European forests are predominantly driven by abundance and accessibility of feeding resources, i.e., insect prey, and their changes across both forest types and latitudes.     

Bats use live fences to move between tropical dry forest remnants

Linear features can benefit wildlife by assisting animal movement. We captured bats along barbed-wire and live-tree fences connecting tropical dry forest patches in Nicaragua. Bat species richness and captures were higher along live fences but we noted differences in sex ratios, richness, and species composition compared to surrounding natural forests.     

Separating the effects of water quality and urbanization on temperate insectivorous bats at the landscape scale

Many local scale studies have shown that bats respond to water quality degradation or urbanization in a species‐specific manner. However, few have separated the effects of urbanization versus water quality degradation on bats, in single city or single watershed case studies. Across North Carolina, USA, we used the standardized North American Bat Monitoring Program mobile transect protocol to survey bat activity in 2015 and 2016 at 41 sites. We collected statewide water quality and urban land cover data to disentangle the effects of urbanization and water quality degradation on bats at the landscape scale. We found that statewide, water quality degradation and urbanization were not correlated. We found that bats responded to water quality degradation and urbanization independently at the landscape scale. Eptesicus fuscus and Lasiurus cinereus negatively responded to water quality degradation. Lasiurus borealis and Perimyotis subflavus positively responded to water quality degradation. Lasionycteris noctivagans did not respond to water quality degradation but was more active in more urbanized areas. Tadarida brasiliensis positively responded to urbanization and was less active in areas with degraded water quality. We show that bat–water quality relationships found at the local scale are evident at a landscape scale. We confirm that bats are useful bioindicators for both urbanization and water quality degradation. We suggest that water quality can be used to predict the presence of bat species of conservation concern, such as P. subflavus, in areas where it has not been studied locally.     

Scale‐dependent effects of forest restoration on Neotropical fruit bats

Neotropical fruit bats (family Phyllostomidae) facilitate forest regeneration on degraded lands by dispersing shrub and tree seeds. Accordingly, if fruit bats can be attracted to restoration sites, seed dispersal could be enhanced. We surveyed bat communities at 10 sites in southern Costa Rica to evaluate whether restoration treatments attracted more fruit bats if trees were planted on degraded farmlands in plantations or island configurations versus natural regeneration. We also compared the relative influence of tree cover at local and landscape spatial scales on bat abundances. We captured 68% more fruit bat individuals in tree plantations as in controls, whereas tree island plots were intermediate. Bat activity also responded to landscape tree cover within a 200‐m radius of restoration plots, with greater abundance but lower species richness in deforested landscapes. Fruit bat captures in controls and tree island plots declined with increasing landscape tree cover, but captures in plantations were relatively constant. Individual species responded differentially to tree cover measured at different spatial scales. We attribute restoration effects primarily to habitat structure rather than food resources because no planted trees produced fruits regularly eaten by bats. The magnitude of tree planting effects on fruit bats was less than previous studies have found for frugivorous birds, suggesting that bats may play a particularly important role in dispersing seeds in heavily deforested and naturally regenerating areas. Nonetheless, our results show that larger tree plantations in more intact landscapes are more likely to attract diverse fruit bats, potentially enhancing seed dispersal.     

Island biogeography of bats in Baja California, Mexico: patterns of bat species richness in a near-shore archipelago

Aim We studied the relationship between the size and isolation of islands and bat species richness in a near‐shore archipelago to determine whether communities of vagile mammals conform to predictions of island biogeography theory. We compared patterns of species richness in two subarchipelagos to determine whether area per se or differences in habitat diversity explain variations in bat species richness. Location Islands in the Gulf of California and adjacent coastal habitats on the Baja California peninsula in northwest Mexico. Methods Presence–absence surveys for bats were conducted on 32 islands in the Gulf of California using acoustic and mist‐net surveys. We sampled for bats in coastal habitats of four regions of the Baja peninsula to characterize the source pool of potential colonizing species. We fitted a semi‐log model of species richness and multiple linear regression and used Akaike information criterion model selection to assess the possible influence of log₁₀ area, isolation, and island group (two subarchipelagos) on the species richness of bats. We compared the species richness of bats on islands with greater vegetation densities in the southern gulf (n = 20) with that on drier islands with less vegetation in the northern gulf (n = 12) to investigate the relationship between habitat diversity and the species richness of bats. Results Twelve species of bats were detected on islands in the Gulf of California, and 15 species were detected in coastal habitats on the Baja peninsula. Bat species richness was related to both area and isolation of islands, and was higher in the southern subarchipelago, which has denser vegetation. Log₁₀ area was positively related to bat species richness, which increased by one species for every 5.4‐fold increase in island area. On average, richness declined by one species per 6.25 km increase in isolation from the Baja peninsula. Main conclusions Our results demonstrate that patterns of bat species richness in a near‐shore archipelago are consistent with patterns predicted by the equilibrium theory of island biogeography. Despite their vagility, bats may be more sensitive to moderate levels of isolation than previously expected in near‐shore archipelagos. Differences in vegetation and habitat xericity appear to be associated with richness of bat communities in this desert ecosystem. Although observed patterns of species richness were consistent with those predicted by the equilibrium theory, similar relationships between species richness and size and isolation of islands may arise from patch‐use decision making by individuals (optimal foraging strategies).     

Experimental rabies virus infection of big brown bats (Eptesicus fuscus)

A captive colony of adult Big Brown Bats (Eptesicus fuscus) was experimentally infected with a rabies virus (RABV) variant isolated from the salivary glands of a naturally infected Big Brown Bat and passaged once through murine neuroblastoma cell culture. Bats were divided into 11 groups, which were composed of one to three noninfected and one to three infected individuals each. Twenty of 38 animals were infected intramuscularly into both left and right masseter muscles; they received a total of 10(3.2) median mouse intracerebral lethal dose (MICLD50) of Big Brown Bat RABV variant. Experimental outcome after viral exposure was followed in the bats for 140 days postinoculation (PI). Of 20 infected bats, 16 developed clinical rabies, and the mean incubation period was 24 days (range: 13-52 days). Three infected bats never seroconverted and succumbed early to infection (13 days). Four infected bats that survived until the end of the experiment without any signs of disease maintained detectable antibody titers until the third month PI, peaking between days 13 and 43, and consequent drop-off below the threshold for detection occurred by day 140. Limited excretion of virus in saliva of infected bats during the clinical course of disease was observed in two individuals on days 13 and 15 PI (<24 hr prior to onset of clinical illness). No bat-to-bat transmission of RABV to noninfected bats was detected.