Bat Pollination Research Articles

Making yourself heard: why well-exposed flowers are an adaptation for bat pollination.

Making yourself heard: why well-exposed flowers are an adaptation for bat pollination.

Bat pollination at the southwestern margin of the Neotropics revealed by direct evidence

AbstractBat pollination at the range margin in the southwestern Neotropics has been largely unexplored. We provide for the first time direct evidence on bat pollination, visitation rate, and efficiency for three species of the Southern Andean Yungas. These interactions are valuable targets for future conservation efforts in this endangered ecosystem.Abstract in Spanish is available with online material.

Bat pollinators: a decade of monitoring reveals declining visitation rates for some species in Thailand

Bats are important pollinators, but they are difficult to study since they are volant and nocturnal. Thus, long-term studies of nectarivorous bats are scarce, despite their potential to help assess trends in bat populations and their pollination services. We used capture rates of nectarivorous bats at chiropterophilous flowers in order to examine temporal trends in bat visitation in an area that is undergoing extensive land use change. We mist-netted at five bat-pollinated plant taxa (Durio zibethinus, Musa acuminata, Oroxylum indicum, Parkia speciosa, and Sonneratia spp.) in southern Thailand over six years between 2011 and 2021. We found that the most common bat species, Eonycteris spelaea, was the main visitor at all five plant taxa and had consistent visitation rates across all study years. In contrast, two other important pollinators, Macroglossus minimus and M. sobrinus, showed 80% declines in the number of individuals netted at mangrove apple (Sonneratia spp.) and banana (Musa acuminata) flowers, respectively. These findings suggest that E. spelaea (a large, cave-roosting species with a broad diet) is more tolerant of anthropogenic change than are Macroglossus bats (small, foliage-roosting species with specialized diets), which may in turn affect the reproductive success of plants pollinated by these species. Our study demonstrates how decade-long monitoring can reveal species-specific temporal patterns in pollinator visitation, emphasizing the need for tailored conservation plans. While the conservation status of most nectarivorous bats in the area is Least Concern, our results indicate that population studies in Southeast Asia are urgently needed for updated bat species conservation assessments.

Dillenia (Dilleniaceae) pollen heteromorphy and presentation, and implications for pollination by bats.

Bat pollination of Dillenia in Fiji, a genus that was presumed to be pollinated by bees, posits that other Dillenia species may be bat-pollinated, with implications for conservation and the understanding of angiosperm evolution. Botanical descriptions of some corolla behaviours ('falling as a whole') suggest bat removal of permanently closed corollas, as in D. biflora. Considering the remoteness of species of interest, we reviewed some Dillenia floral traits to hypothesise what they may mean for bat pollination of the genus. We investigated D. biflora pollen grains apertures and reviewed Dillenia literature concerning corolla behaviour and colour, and pollen apertures and presentation, including pores and staminodes. Our samples had dramatically different ratios of tricolpate to tetracolpate pollen grains, a trait that does not exclude pollination by bees. Petal colour polymorphism occurs, with mixed colours proportionately less common in flowers with corollas that open. The proportion of species with staminodes did not differ between those presumed to be pollinated by bats and others, but anthers of the former were significantly more likely to have apical pores, and stamens all had similar length or were slightly longer in the middle, whereas stamens in two distinct groups occurred in 55% of bee-pollinated species. Pollen heteromorphy may facilitate pollination by different taxa in tropical environments. However, anther apical pores and stamen uniformity are more likely to be associated with bat-pollinated species than are other morphologies. Dillenia could be a useful model to examine evolutionary aspects of colour, heteranthery, staminodes and pollen heteromorphy. Only field work will verify bat pollination and the implications of bat dependence for Dillenia species.

Molecular phylogeny and evolution of inflorescence types in Eperua.

The Amazonian hyperdominant genus Eperua (Fabaceae) currently holds 20 described species and has two strongly different inflorescence and flower types, with corresponding different pollination syndrome. The evolution of these vastly different inflorescence types within this genus was unknown and the main topic in this study. We constructed a molecular phylogeny, based on the full nuclear ribosomal DNA and partial plastome, using Bayesian inference and maximum likelihood methods, to test whether the genus is monophyletic, whether all species are monophyletic and if the shift from bat to bee pollination (or vice versa) occurred once in this genus. All but two species are well supported by the nuclear ribosomal phylogeny. The plastome phylogeny, however, shows a strong geographic signal suggesting strong local hybridization or chloroplast capture, rendering chloroplast barcodes meaningless in this genus. With our data, we cannot fully resolve the backbone of the tree to clarify sister genera relationships and confirm monophyly of the genus Eperua. Within the genus, the shift from bat to bee and bee to bat pollination has occurred several times but, with the bee to bat not always leading to a pendant inflorescence.

Repeated evolution of pollination syndromes in a highly diverse bromeliad lineage is correlated with shifts in life form and habitat

AbstractMutualistic plant-pollinator interactions play a critical role in the diversification of flowering plants. The spatiotemporal correlates of such interactions can be understood in a phylogenetic context. Here, we generate ddRAD-seq data for the highly diverse Vriesea-Stigmatodon lineage to test for correlated trait evolution among pollination syndromes and life form, habitat type, and altitude. Our results show that pollination syndromes are correlated with changes in life form and habitat type. The ancestor of the Vriesea-Stigmatodon lineage was likely bat pollinated, rock dwelling and inhabited open, mid-elevation forests. Transitions from bat to hummingbird pollination are correlated with transitions to the epiphytic life form in shaded habitats, whereas bat pollination is correlated with the rock-dwelling life form and open habitats. Our dated phylogenetic tree reveals independent origins of hummingbird pollination, occurring twice in Vriesea at c. 5.8 and 5.4 Mya. The timing for the shifts in pollination syndrome coincides with geological and environmental transformations across the Serra do Mar Mountain Chain, which increased habitat heterogeneity where Vriesea and their mutualists diversified. The phylogenetic tree reinforces the non-monophyly of taxonomic sections within the genus Vriesea previously defined by flower morphology, indicating that some lineages should be treated as species complexes. This study identifies synergetic drivers of speciation in a tropical biodiversity hotspot.

Position control of a ball balancer system using Particle Swarm Optimization, BAT and Flower Pollination Algorithm

ABSTRACT The design and control of the 2DoF Ball Balancer system is presented in this work. The ball balancer is a feedback-based underactuated system that is nonlinear, multivariate, and electromechanical. The proportional derivative (PD) controller is optimized by using Bat Algorithm, Particle Swarm Optimization, and Flower Pollination Algorithm in this research. By regulating the plate inclination angle, the suggested controller accomplishes self-balancing control for a ball on the plate. The modelling of the ball balancer system is accomplished using a 2DoF ball balancer system. In addition, Bat Algorithms, Particle Swarm Optimization, and the Flower Pollination Algorithm are used to analyze the state of a process autonomously. The system's model is created using MATLAB/Simulink approaches, and the results present the system with a steady and controllable output for ball balancing and plate angle control.

Hairy cactus parts make flowers stand out to bats

Animals that pollinate plants are incredibly important to life as we know it. Almost all crops grown by humans are pollinated by animals. While we all know that insects pollinate lots of plants, most of us are, generally, less familiar with the role that bats play in spreading pollen between plants. But bats are active at night, so how do plants attract bats if they can't see their colourful flowers? Ralph Simon from Nuremberg Zoo, Germany, and Wouter Halfwerk of Vrije Universiteit, The Netherlands, believe that the cactus Espostoa frutescens from the Ecuadorian Andes uses the hairs around their flowers to help bats locate them using sonar.Working alongside Felix Matt of Philipps-University of Marburg, Germany, Vinicio Santillan of Universidad Católica de Cuenca, Ecuador, Marco Tschapka of the University of Ulm, Germany, and Merlin Tuttle of Merlin Tuttle's Bat Conservation, USA, Simon and Halfwerk tested their hypothesis by bouncing soundwaves off different parts of the cactus and recording the returning echoes just as a bat would. The team found that when sound rebounded off the stem, or column, of the cactus, they received a loud echo in response. In other words, a lot of sound was reflecting off the column of the cactus. The researchers saw a slightly quieter echo returning from the flowers. But when Simon and colleagues bounced sounds off the hairy, almost beard-like structure surrounding the flowers, they found that the hairs were absorbing the sound, and almost no echo was received by the recording device.Prior to this, many theories had been put forth about the purpose of these hairy growths on the cacti, from protection from predators to shielding new buds from the harmful effects of the sun at such high altitudes. However, Simon and colleagues thought that the hairy area around the flowers might be helping bat pollinators home in on the flowers themselves. To test their hypothesis, the researchers removed the flowers from the hairy area and pinned them to another part of the cactus, free from hairs. When the team bounced the sound off the hairless part of the cactus with the flower there, it was almost impossible to distinguish the echo coming from the flower amongst the echoes coming from the other parts of the cactus. If the flowers were still nested in their hairy homes, the contrast between echoes of the flowers and the almost non-existent echoes from the hairs made the flowers stand out against the hairy backdrop.The team then recorded calls from the bat pollinator, Geoffroy's tailless bat (Anoura geoffroyi), as they were approaching the flowers and compared these with the echoes they were receiving from the cacti. It turns out that the hairs are particularly good at absorbing sounds in the frequency of the bat's sonar calls, around 90 kHz. Simon and colleagues also noted that the bats’ ears would receive faint echoes bouncing off the hairy surface until the sonar hit a flower, which would then make the echoes much louder.The researchers suggest that because bats need to visit hundreds of flowers every night to recover how much energy they use throughout the day, having these hairy patches surrounding the flowers helps them save time searching – which helps the cactus as well. ‘Bats are very efficient pollinators that carry a lot of pollen in their fur and travel huge distances daily, so they can pollinate plants growing far apart’, states Simon. So, while many plants have evolved bright colours and delicious scents to entice pollinators to visit, these desert cactuses have gotten hairy instead.

A negative association between nectar standing crop and pollen transfer suggests nectar functions as a manipulator of pollinating bats.

Nectar standing crop has a fundamental role in controlling pollinator movements between flowers and individuals within a population. In bat pollination systems, plants take advantage of the cognitive abilities of nectarivorous bats, which integrate complex perceptions of the quality and spatial distribution of resources. Here, we propose that associations between standing crop and pollen transfer help to reveal the role of nectar as a manipulator of pollinator behaviour. We used Harpochilus neesianus Ness (Acanthaceae), a bat-pollinated shrub from the Brazilian Caatinga, as a model system to assess nectar removal effects and standing crop, respectively, over the night and to test associations between the amount of nectar available to pollinators, and pollen import and export. Harpochilus neesianus showed continuous nectar secretion throughout the flower lifespan. Flowers subjected to successive nectar removals produced less nectar than flowers sampled just once, and showed, despite a higher sugar concentration, a lower absolute amount of sugar. Under these conditions, bats may realize that nectar production is decreasing after repeated visits to the same flower and could be manipulated to avoid such already pollinated flowers with little nectar, thus increasing the probability of visits to flowers with a high amount of nectar, and a still high pollen availability on anthers and low pollen deposition on stigmas. We found that during most of the period of anthesis, nectar standing crop volume was positively correlated with the number of pollen grains remaining in the anthers, and negatively with the number of pollen grains deposited on the stigma. Nectar secretion patterns can function as a manipulator of pollinating bats in H. neesianus. We propose that the assessment of variability in nectar secretion in response to removal, and the correlation between nectar standing crop and relative pollen transfer throughout anthesis should be considered in order to understand the role of nectar in the manipulation of pollinators.

Divergent strategies of nectar secretion in two bat-pollinated Passiflora species

The secretion dynamics and chemical compositions of flower nectar can vary according to the plant physiology and the pollinator type. Bat-pollinated flowers are commonly associated with nocturnal nectar secretion as well as large amounts of nectar per flower, which is generally diluted and composed mostly of hexose sugars. The nectar traits in bat-pollinated Passiflora species are poorly understood and in this work, we describe these for two such species. We conducted field experiments to assess the nectar secretion dynamics of two species with nocturnal anthesis and similar colours and structures, performed chemical analyses of the sugar components of nectar from these two species, and combined these data with systematic observations of floral visitors. The nectar dynamics of both Passiflora species are similar to those of other bat-pollinated species. In Passiflora mucronata, nectar secretion starts before the flower opens, which occurs around 04h00, with secretion ending after 10h00. Passiflora setacea starts secreting nectar at the time of flower opening, around 22h00, finishing secretion between 04h00 and 06h00. In P. setacea, the final period of anthesis is characterised by active nectar resorption. The different blooming times of these two bat-pollinated passionflowers and the significant differences in their nectar secretion schedules suggest a divergent nectar secretion dynamics: the nectar of P. mucronata is made available only by the end of the bats’ foraging activity period, continuing throughout the morning, while P. setacea secretes nectar earlier, with very little overlap in the secretion period between the species. We hypothesise that this segregation in time helps avoid the negative effects from competition for pollinators or pollen interference between flowers with a similar structure, while the outstanding nectar traits and the constant production of flowers throughout the year make these closely related vines important nectar sources for their bat pollinators where they co-occur.

Changing the main course: strong bat visitation to the ornithophilous mistletoe Psittacanthus robustus (Loranthaceae) in a Neotropical savanna

AbstractThe Neotropical genus Psittacanthus comprises mostly specialized ornithophilous mistletoes, with rare exceptions. Psittacanthus robustus is a common ornithophilous species from the South American savannas whose bright yellow flowers secrete copious diluted nectar. Due to a three‐day‐long anthesis and a short, non‐restrictive floral tube, we suggest that the species also serves as a resource for flower‐visiting bats. In a Cerrado area in central Brazil, we investigated the usage of the species by bats through systematic bat captures for pollen sampling, its nocturnal nectar secretion dynamics, mating system, and the relative dependence on diurnal and nocturnal pollinators for reproduction. Nine phyllostomid bat species visited P. robustus. Up to 50% of pollen samples from bats contained the species during peak flowering, equating or surpassing the prevalence of chiropterophilous species and representing roughly a third of the floral resources consumed by specialized nectarivores Glossophaga soricina and Anoura caudifer. Flowers actively produced nectar at night with volume and concentration values in the ideal ranges for bat consumption. Nectar is continuously secreted after sunset and accumulates in the absence of visitors. Psittacanthus robustus is self‐compatible but seeds are set mostly by diurnal visitors. Nocturnal animals had a low and secondary contribution to plant fitness. This is the second report of bat pollination for the genus Psittacanthus, and the largest assemblage of bat visitors for the family Loranthaceae. Although ornithophilous, P. robustus is an important resource for bats in the Brazilian savanna, potentially representing a mixed or early transitional state toward bat pollination.Abstract in Portuguese is available with online material.

A novel bat pollination system involving obligate flower corolla removal has implications for global Dillenia conservation.

The Dilleniaceae is known to produce nectarless flowers pollinated by bees, but the fact that bats ingest Dillenia biflora pollen led us to question pollination assumptions for these trees. We aimed to identify the pollinators of D. biflora, check for nectar presence, and investigate potential for cleistogamy and global prevalence of this pollination system. We examined aspects of the pollination of D. biflora on two Fijian islands using video recordings, direct observations, hand pollination, measurements (flowers, bite marks, nectar), and monitoring. The flowers, receptive for one night, contained copious nectar and had permanently closed globose corollas that required removal by bats for pollination. All the 101 flowers that retained their corolla died and did not produce seeds by cleistogamy. The bat Notopteris macdonaldi was well adapted to corolla removal. Keeping corollas closed until bats manipulate the nectar-rich flowers is a beneficial strategy in high-rainfall environments with many flower parasites. We propose to name a pollination system reliant exclusively on bats “chiropteropisteusis.” From clues in the literature, other species in the geographical range of Dillenia are probably chiropteropisunous. Chiropteropisteusis should be investigated in the Old-World range of Dillenia, many species of which are threatened. The remarkable “fall” of the entire corolla observed by an earlier botanist for several species in the genus is most likely attributable to bats. This discovery has important implications for the conservation of bat-dependent trees and their associated fauna, particularly considering the high level of threat faced by flying-foxes globally.

Negative effects of light pollution on pollinator visits are outweighed by positive effects on the reproductive success of a bat-pollinated tree

Cities are home to several species of pollinators that play an important role in the reproductive success of wild and cultivated plants that grow in these ecosystems and their surroundings. Pollution is a main driver of pollinator decline. Light and noise pollution are more intense in cities than in any other ecosystem. Although nocturnal pollinators are heavily exposed to these pollutants, their effect on bat pollination is still unknown. Our goal was to assess the effect of light and noise pollution on the main pollination components (pollinator visits, pollen transfer, pollen germination, fruit, and seed set) of the tropical tree, Ceiba pentandra, in a heavily urbanized ecosystem. We measured these components in sites with contrasting intensities of artificial light and anthropogenic noise and statistically assessed the direct and indirect effect of pollutants on pollination components using structural equation modeling. We found that noise and light pollution negatively affected the visits by the bats that pollinate C. pentandra. However, these negative effects did not affect posterior pollination components. In fact, the direct effect of light pollution on reproductive success was positive and greater than the indirect effects via pollinator visits. We suggest that illuminated trees may be able to sustain a large quantity of fruits and seeds because they produce more photosynthates due to greater light radiation and delayed leaf abscission. We conclude that, despite the negative effect of light and noise on pollinator visits, these pollutants did not significantly impact the reproductive success of C. pentandra.

Evidence for hawkmoth pollination in the chiropterophilous African baobab (Adansonia digitata)

AbstractChiropterophily, or bat pollination, is typically considered a highly specialized pollination system that has evolved independently numerous times across the angiosperm phylogeny, with distinct lineages often converging on a similar suite of floral traits. The African baobab, Adansonia digitata, occurs widespread across continental Africa and introduced throughout much of the tropics, possesses floral traits classically associated with bat pollination, namely nocturnal anthesis, pendulous white flowers, and a “musky” fragrance. Despite this, our observations and pollination exclusion experiments in South African baobab populations suggested little if any role for bats, but instead showed that hawkmoths are the main pollinators. Hand pollination indicated strong self‐incompatibility and crossing experiments suggest minimal diurnal receptivity. Furthermore, our analyses of floral volatiles revealed not only sulfur‐containing compounds, commonly associated with bat pollination, but also a high concentration of the sesquiterpene β‐caryophyllene, a compound generally more typical of hawkmoth pollination. Comparing previous pollination studies and published floral scent profiles from West Africa suggests that the classic bat pollination system in baobabs may be more labile than previously thought. This study provides an empirical example of a species that most likely evolved due to bat pollination yet has some degree of generality and possible geographic variation in floral traits and pollinator visitation patterns across its range.

Bat–flower interaction networks in Caatinga reveal generalized associations and temporal stability

AbstractSeasonal variation in precipitation regimes influences species composition and plant–animal interactions. Such temporal variation is especially relevant in the Brazilian Caatinga, the largest Seasonally Dry Tropical Forest in South America, where bat pollination is unusually frequent in comparison with other tropical plant communities. Here, we describe seasonal and annual variations of the interaction networks between nectarivorous bats and flower species in the Caatinga. Five species of nectar‐feeding bats interacted with 30 plant species. Nectarivorous bats showed high levels of interaction overlap, which contributed to ecological generalization (low specialization and modularity) and lack of nestedness in the interaction networks. This pattern was consistent across seasons and years. Chiropterophilous and non‐chiropterophilous plants were equally important components of the interaction network. The generalized interaction patterns found may be a necessary condition for the persistence of nectarivorous bats and their specialized plants in the environmentally harsh and variable Caatinga. The underappreciated generalized interactions of bats with plants calls for studies testing the effectiveness of bats in pollinating the plants they visit, including those not typically categorized as “bat‐flowers”.Abstract in Portuguese is available with online material.

Free amino acids in nectar: its composition and variability among bat-pollinated plants

Regardless of the low concentrations at which amino acids are present in floral nectar of bat-pollinated plants, their role as nectar flavor providers and their influence on bats’ foraging decisions have been recognized. Nevertheless, variation in the free amino acids among bat-pollinated plant species has been less studied. The goal of this study was to analyze the nectar free amino acids and to determine its variability among 8 bat-pollinated plant species from 5 families in a Tropical Dry Forest in Mexico. Nectar collections were made opportunistically depending on plants flowering season. We quantified 17 amino acids by HPLC. All 17 free amino acids were present in nectar from the 8 analyzed plant species. The concentration of 12 amino acids is explained by plant species by 19-58%. Analyses showed that Ceiba grandiflora (Malvaceae) was significantly different in asparagine content when compared to Bahuinia pauletia (Fabaceae) and Ceiba aesculifolia (Malvaceae), and in glutamic acid when compared to Ipomoea ampullacea (Convolvulaceae). We discuss the importance of free amino acids in nectar among plant species and their influence on bat pollination ecology.

Gongylolepis martiana, an Asteraceae pollinated by bats in the Amazon.

Most Asteraceae species are pollinated by insects, mainly bees and butterflies, although pollination by birds has been documented and pollination by bats has been suggested for some species. Here, we investigated the pollination of Gongylolepis martiana, a species supposedly pollinated by bats. We assessed floral traits and visitors in a population of G. martiana in the Brazilian Amazon, measuring pollen removal from anthers and deposition on stigmas by diurnal and nocturnal visitors. Florets opened at dusk and lasted for 4days, with the male phase starting on the first night and the female phase on the third night. Accumulated nectar per capitulum was 69.6μl per night and sugar concentration was 15%. Nectar-feeding bats and hummingbirds contacted the sexual parts, but pollen removal and deposition were greater throughout the night than during the day, when Meliponini bees considerably reduced pollen availability. Other nocturnal visitors of G. martiana were rare, including nocturnal bees and moths that foraged for pollen and nectar, respectively. Our results support that nectarivorous bats are the main pollinators of G. martiana, confirming Vogel's hypothesis of bat pollination in Asteraceae, particularly in the genus Gongylolepis. Since anthesis and each sexual floral phase started in the evening, nectarivorous bats and diurnal bees caused additive priority effects, preventing hummingbirds from being efficient pollinators. The high density of flowering individuals of G. martiana in patches from white-sand forests likely increases bat attraction, while the small amount of nectar per plant favours cross-pollination.

Vulnerability of bat-plant pollination interactions due to environmental change.

Plant-pollinator interactions are highly relevant to society as many crops important for humans are animal pollinated. However, changes in climate and land use may put such interacting patterns at risk by disrupting the occurrences between pollinators and the plants they pollinate. Here, we analyse how the co-occurrence patterns between bat pollinators and 126 plant species they pollinate may be disrupted given changes in climate and land use, and we forecast relevant changes of the current bat-plant co-occurrence distribution patterns for the near future. We predict under RCP8.5 21% of the territory will experience a loss of bat species richness, plants with C3 metabolism are predicted to reduce their area of distribution by 6.5%, CAM species are predicted to increase their potential area of distribution up to 1% and phanerophytes are predicted to have a 14% reduction in their distribution. The potential bat-plant interactions are predicted to decrease from an average of 47.1 co-occurring bat-plant pairs in the present to 34.1 in the pessimistic scenario. The overall changes in suitable environmental conditions for bats and the plant species they pollinate may disrupt the current bat-plant co-occurrence network and will likely put at risk the pollination services bat species provide.

Phylogeny and Systematics of Crescentieae (Bignoniaceae), a Neotropical Clade of Cauliflorous and Bat-Pollinated Trees

Abstract—The tribe Crescentieae includesAmphitecna(21 species),Crescentia(six species), andParmentiera(10 species), three genera of understory trees with a center of diversity in Central America and a small number of species in the Antilles and northern South America. Species in Crescentieae are united by their fleshy, indehiscent fruit and cauliflorous, bat-pollinated flowers. To lay a foundation for examining morphological, ecological, and biogeographic patterns within the tribe, we inferred the phylogeny for Crescentieae using both chloroplast (ndhF,trnL-F) and nuclear markers (PepC, ITS). The most recent circumscription of Crescentieae, containingAmphitecna,Crescentia, andParmentierais supported by our phylogenetic results. Likewise, the sister relationship between Crescentieae and the Antillean-endemicSpirotecomais also corroborated by our findings. This relationship implies the evolution of fleshy and indehiscent fruits from dry and dehiscent ones, as well as the evolution of bat pollination from insect pollination. Fruits and seeds from species in Crescentieae are consumed by humans, ungulates, birds, and fish.

The functional ecology of bat pollination in the African sausage tree Kigelia africana (Bignoniaceae)

AbstractPlants often interact with a wide range of animal floral visitors that can vary in their pollination effectiveness. Flowers of the African sausage tree Kigelia africana are visited by bats and bush babies during the night and by birds during the day. We studied floral traits (phenophases, scent, color, and nectar chemistry) and the visitation frequency and pollination effectiveness of different flower visitors to determine whether K. africana is functionally specialized for bat pollination. We found that flower opening corresponds with bat activity, flowers emit scent dominated by aliphatic esters and alcohols, and that nectar is produced in copious amounts accessible to bats. Pollen deposition on stigmas was twenty‐fold greater per visit by bats than it was per visit by birds, likely a result of the close morphological fit between snouts of bats and the flowers. However, bat visits appear to be rare at some sites and the delayed senescence of flowers that are open throughout the morning provides an opportunity for additional pollination by birds. We conclude that K. africana is primarily adapted for bat pollination, but is also able to exploit other animals for pollination.