Pollinator Species Research Articles

Land-use affects pollinator-specific resource availability and pollinator foraging behaviour.

Land-use management is a key factor causing pollinator declines in agricultural grasslands. This decline can not only be directly driven by land-use (e.g., habitat loss) but also be indirectly mediated through a reduction in floral resource abundance and diversity, which might in turn affect pollinator health and foraging. We conducted surveys of the abundance of flowering plant species and behavioural observations of two common generalist pollinator species, namely the bumblebee Bombus lapidarius and the syrphid fly Episyrphus balteatus, in managed grasslands of variable land-use intensity (LUI) to investigate whether land-use affects (1) resource availability of the pollinators, (2) their host plant selection and (3) pollinator foraging behaviour. We have found that the floral composition of plant species that were used as resource by the investigated pollinator species depends on land-use intensity and practices such as mowing or grazing. We have also found that bumblebees, but not syrphid flies, visit different plants depending on LUI or management type. Furthermore, LUI indirectly changed pollinator behaviour via a reduction in plot-level flower diversity and abundance. For example, bumblebees show longer flight durations with decreasing flower cover indicating higher energy expenditure when foraging on land-use intensive plots. Syrphid flies were generally less affected by local land use, showing how different pollinator groups can differently react to land-use change. Overall, we show that land-use can change resource composition, abundance and diversity for pollinators, which can in turn affect pollinator foraging behaviour and potentially contribute to pollinator decline in agricultural grasslands.

Toxicity and Risk of Biopesticides to Insect Pollinators in Urban and Agricultural Landscapes

Pollinators play important roles in providing pollination services, maintaining biodiversity, and boosting crop production. Even though pollinators are essential to the environment and agriculture, their decline has been noted across multiple studies in the recent past. Both natural and anthropogenic factors have contributed to their decline. Much of the focus has been placed on climate change, habitat loss, pests and pathogens, and synthetic pesticides, but relatively little is known about the effects of biopesticides. Biopesticides are biological control agents derived from living organisms and are classified into three groups: microbial, biochemical, and plant-incorporated protectant-based products. Biopesticides are formulated similarly to their synthetic counterparts and are readily available and used within urban and agricultural settings by pest management experts and household residents. The general public and much scientific literature support the prevailing idea that biopesticides are environmentally safe and pollinator friendly in comparison with synthetic versions. However, such generalizations are based on studies with a few key pollinator species and may not be relevant to several other species that provide crop pollination services. Studies focused on native pollinators have shown that some biopesticides have lethal and sublethal effects. Because each biopesticide exhibits varying effects across pollinator species, it could be dangerous to generalize their non-toxicity across taxa and environmental settings. In this article, recent research in this direction is discussed.

Differential response of plant and insect pollinator communities to fragmentation in coastal dune slacks

Abstract Habitat destruction and fragmentation are one of the main drivers of pollinator decline and biodiversity loss in general. However, the exact effects of habitat fragmentation on pollinator communities are still poorly understood, and it remains unclear which patch characteristics are most important in driving pollinator diversity and community composition. In this study, we inventoried plant and insect diversity in a total of 19 fragmented dune slacks in Belgium. Specifically, we assessed the effects of dune slack area and connectivity on plant and pollinator diversity and community composition. Additionally, we investigated to what extent plant diversity had an impact on insect pollinator communities. The results indicated that species richness of both plants and insects was significantly related to patch area, whereas patch connectivity only had a significant effect on plant diversity. Nestedness analyses showed that plant communities of small dune slacks were a subset of the communities of large patches, but no such patterns were found for insect communities. Turnover in pollinator communities was high and significantly related to the distance separating dune slacks. Overall, our results highlight the importance of large patches for sustaining both plant and pollinator communities. Additionally, enhancing connectivity has the potential to promote plant diversity and consequently benefit pollinator species.

Effect of green infrastructure on restoration of pollination networks and plant performance in semi‐natural dry grasslands across Europe

Abstract Agricultural intensification, afforestation and land abandonment are major drivers of biodiversity loss in semi‐natural grasslands across Europe. Reversing these losses requires the reinstatement of plant–animal interactions such as pollination. Here we assessed the differences in species composition and patterns of plant‐pollinator interactions in ancient and restored grasslands and how these patterns are influenced by landscape connectivity, across three European regions (Belgium, Germany and Sweden). We evaluated the differences in pollinator community assemblage, abundance and interaction network structure between 24 ancient and restored grasslands. We then assessed the effect of surrounding landscape functional connectivity (i.e. green infrastructure, GI) on these variables and tested possible consequences on the reproduction of two model plants, Lotus corniculatus and Salvia pratensis. Neither pollinator richness nor species composition differed between ancient and restored grasslands. A high turnover of interactions across grasslands was detected but was mainly due to replacement of pollinator and plant species. The impact of grassland restoration was consistent across various pollinator functional groups, whereas the surrounding GI had differential effects. Notably, bees, butterflies, beetles, and dipterans (excluding hoverflies) exhibited the most significant responses to GI variations. Interestingly, networks in restored grasslands were more specialised (i.e. less functionally redundant) than in ancient ones and also showed a higher number of insect visits to habitat‐generalist plant species. Landscape connectivity had a similar effect, with habitat‐specialist plant species receiving fewer visits at higher GI values. Fruit set in S. pratensis and L. corniculatus was unaffected by grassland type or GI. However, the fruit set in the specialist S. pratensis increased with the number of pollinator visits, indicating a positive correlation between pollinator activity and reproductive success in this particular species. Synthesis and applications. Our findings provide evidence of the necessity to enhance ecosystem functions while avoiding biotic homogenisation. Restoration programs should aim at increasing landscape connectivity which influences plant communities, pollinator assemblages and their interaction patterns. To avoid generalist species taking over from specialists in restored grasslands, we suggest reinforcing the presence of specialist species in the latter, for instance by means of introductions, as well as increasing the connectivity to source populations.

Multitrophic Higher-Order Interactions Modulate Species Persistence.

AbstractEcologists increasingly recognize that interactions between two species can be affected by the density of a third species. How these higher-order interactions (HOIs) affect species persistence remains poorly understood. To explore the effect of HOIs stemming from multiple trophic layers on a plant community composition, we experimentally built a mesocosm with three plants and three pollinator species arranged in a fully nested and modified network structure. We estimated pairwise interactions among plants and between plants and pollinators, as well as HOIs initiated by a plant or a pollinator affecting plant species pairs. Using a structuralist approach, we evaluated the consequences of the statistically supported HOIs on the persistence probability of each of the three competing plant species and their combinations. HOIs substantially redistribute the strength and sign of pairwise interactions between plant species, promoting the opportunities for multispecies communities to persist compared with a non-HOI scenario. However, the physical elimination of a plant-pollinator link in the modified network structure promotes changes in per capita pairwise interactions and HOIs, resulting in a single-species community. Our study provides empirical evidence of the joint importance of HOIs and network structure in determining species persistence within diverse communities.

Assessing pollinator habitat suitability considering ecosystem condition in the Hannover Region, Germany

Abstract Context Habitat suitability for pollinator species is an important indicator for pollination ecosystem service potential, i.e. for biodiversity and crop provision. Modelling habitat suitability using an expert- and process-based models such as ESTIMAP-pollination is a common and accepted approach to spatially analyse pollination service potential and to make recommendations for planning. Objectives However, the suitability as a pollinator habitat depends not only on the land use type. It is also important to consider the condition of the habitat. For this reason, ecosystem condition information was used as a parameter for ESTIMAP modelling for the first time. Ecosystem condition data was used besides the commonly (in ESTIMAP) used information from expert assessments and from land use data. Methods As parameters for ecosystem condition, the management intensity in agro ecosystems, the management of forests and the proportion of green space in urban areas were included and affected the modelled habitat suitability for wild bees. Results Not all ecosystem types of the region were equally affected by the inclusion of the ecosystem condition parameter in the model. The most affected types were agricultural areas, such as arable and horticultural biotopes, whose suitability values decreased by 25.7%. As a result, areas with low suitability account for 41% of the region and 76.6% of the agro ecosystems. In forest, shrubs and woody plants land use types, the suitability decreased respectively by 4.3 and 6%. On the other hand, urban ecosystems in the city of Hannover were characterised by relatively good habitat suitabilities, especially in the proximity of wide urban forests. In 3.4% of the agricultural land, measures to support pollinators have been established. 1.6% of these measures are located in areas with low suitability. Conclusions The results show that ecosystem condition is, in addition to land use type, an important parameter to indicate habitat suitability for pollinators. Especially for ecosystem types with varying habitat suitabilities, such as agro ecosystems, the implementation of ecosystem condition parameters is recommendable. However, the selection of suitable ecosystem condition indicators still requires further research and concise definitions.

Loss of functional diversity rather than species diversity of pollinators decreases community‐wide trait matching and pollination function

Abstract Loss of animal species and functional diversity can degrade ecosystem functions and services in plant–animal mutualistic networks, but their relative effects have rarely been previously examined in natural communities. Contrary to previously published theoretical results, under natural conditions, changes in pollinator functional niches caused by species and functional diversity losses are dynamic and often unpredictable. The lack of studies on natural networks limits our ability to predict future effects of decreasing pollinator diversity on wild and cultivated plants. We quantitatively evaluated the relative effects of pollinator species and functional diversity loss on plant–pollinator trait matching and pollination success across 40 spatiotemporally variable coastal networks. We found that low pollinator functional diversity (low abundance of long‐tongued pollinators) reduced community‐level plant functional specialization and trait matching between flowers and pollinators by reducing functional floral‐niche partitioning among pollinators. In contrast, pollinator species diversity did not influence community‐level trait matching. Furthermore, decreasing community‐level trait matching had a negative effect on community‐level plant pollination success, regardless of flower morphology. The present study demonstrated that pollinator functional diversity loss, rather than species diversity loss, was the main factor contributing to pollination functional loss in the plant–pollinator networks studied. We also demonstrated the importance of assessing functional aspects of plant–pollinator networks to evaluate community‐level pollination functional loss under global pollinator decline. Read the free Plain Language Summary for this article on the Journal blog.

Pesticide hazard, floral resource availability and natural enemies interactively drive the fitness of bee species depending on their crop fidelity

Pesticides, loss of floral resources and parasitism are considered drivers of wild bee decline in agroecosystems, but their interactions are poorly understood under field conditions. Negative impacts are predicted to vary across species of distinct crop fidelity because of the associated consequences for pesticide exposure and dependence on wild flowers. We experimentally established populations of two solitary bee species in apple orchards with distinct pesticide hazard and flower availability in surrounding landscapes. The number of nesting females, their reproduction and offspring survival and parasitism rate were tracked throughout apple bloom. We show that in the solitary bee Osmia cornuta, which showed a strong preference to forage in apple orchards, the number of females remaining at nesting sites towards the end of apple bloom and the overall reproductive success of the released bees declined with pesticide hazard. In contrast, the closely related Osmia bicornis, which showed a lower preference for apple, was not affected by pesticide use in orchards. Floral resource distribution furthermore modulated parasitism rates in both species: while large amounts of locally available resources reduced offspring parasitism, it increased with relatively higher food availability in the landscapes surrounding focal orchards, probably due to the bees foraging on a larger scale and thus longer periods during which nests remained unattended. Our findings provide novel insights into the complex interplay of pesticide exposure, flower availability and parasitism risk driving population dynamics of bees in agroecosystems. They show that in particular the most reliable crop pollinator species are especially harmed by high pesticide use in crops. Our study underpins the key role of reducing pesticide risks for pollinators through effective regulation of potentially hazardous agrochemicals and the promotion of alternative pest regulation approaches along with conserving and restoring flower-rich habitats to sustain pollinator populations in agroecosystems.

A role for DNA methylation in bumblebee morphogenesis hints at female-specific developmental erasure.

Epigenetic mechanisms, such as DNA methylation, are crucial factors in animal development. In some mammals, almost all DNA methylation is erased during embryo development and re-established in a sex- and cell-specific manner. This erasure and re-establishment is thought to primarily be a vertebrate-specific trait. Insects are particularly interesting in terms of development as many species often undergo remarkable morphological changes en route to maturity, that is, morphogenesis. However, little is known about the role of epigenetic mechanisms in this process across species. We have used whole-genome bisulfite sequencing to track genome-wide DNA methylation changes through the development of an economically and environmentally important pollinator species, the bumblebee Bombus terrestris (Hymenoptera:Apidae Linnaeus). We find overall levels of DNA methylation vary throughout development, and we find developmentally relevant differentially methylated genes throughout. Intriguingly, we have identified a depletion of DNA methylation in ovaries/eggs and an enrichment of highly methylated genes in sperm. We suggest this could represent a sex-specific DNA methylation erasure event. To our knowledge, this is the first suggestion of possible developmental DNA methylation erasure in an insect species. This study lays the required groundwork for functional experimental work to determine if there is a causal nature to the DNA methylation differences identified. Additionally, the application of single-cell methylation sequencing to this system will enable more accurate identification of if or when DNA methylation is erased during development.

Heatwaves increase larval mortality and delay development of a solitary bee

Abstract Heatwaves are expected to increase in frequency, intensity and duration due to climate change. For organisms like insects with discrete development, sensitivity may differ among life stages. Thermal sensitivity is of particular concern for species like bees that provide critical ecosystem services. Although social bees moderate nest temperatures through worker behaviour, solitary bees do not thermoregulate their nests, making immobile developing offspring especially vulnerable to such extreme events. We studied the effects of heatwaves on larval development in the solitary bee, Osmia lignaria, an important orchard pollinator and model species for solitary bee biology. We used a factorial design to assess the impacts of heatwave temperature and duration on larval mortality and development rate. Larvae were exposed to heatwaves under realistic diel temperature regimes, with daytime maxima of 31 or 37°C for 4 or 7 days at the beginning of development. Heatwave temperature strongly affected larval mortality. Exposure to 37°C heatwaves increased larval mortality by 130%, but the cooler 31°C heatwaves did not significantly impact mortality. Heatwave duration did not impact larval mortality. Larval development time also was affected by heatwave exposure. Compared with the no‐heatwave‐control, bees in the 31°C heatwave developed faster, and bees in the 37°C heatwave developed slower. Our study reveals the importance of stage‐specific effects of extreme events and suggests that the timing and maximum temperature of projected heatwaves may be more detrimental to populations than heatwave duration.

Diversity and foraging activity of coffee insect pollinators in land near and far from the forest of North Sumatra, Indonesia

Abstract. Sinaga RR, Maryana N, Hidayat P. 2024. Diversity and foraging activity of coffee insect pollinators in land near and far from the forest of North Sumatra, Indonesia. Biodiversitas 25: 240-248. Coffee (Coffea spp.) is among the plant species that depend on insects to aid in its pollination process, where insect pollinators serve as intermediaries facilitating plant pollination. This study examined the diversity, abundance, and visiting activity of insect pollinators in coffee cultivation located in different areas, specifically those near the forest and those far from the forest in Simalungun District, North Sumatra. The study was carried out from September 2022 to February 2023 in six coffee cultivation sites spread across four sub-districts in Simalungun District, i.e., Silimakuta, Pematang Silimakuta, Purba, and Dolok Silau. The study's results revealed the presence of 16 species of insect pollinators in coffee cultivation near the forest and 13 species in those located far from the forest. The identified insect pollinators species were from Order Hymenoptera; Apis cerana, Lasioglossum sp., Dolichovespula norvegicoides, Diptera; Stomorhina discolor, Musca domestica, Bactrocera papayae, Nephrotoma flavescens, Episyrphus viridaureus, Oebalia sp., Coleoptera; Pachnaeus sp., Cantharis sp., Scarabaeidae sp 1., Maladera japonica, Lepidoptera; Agrotis segetum, Bradina diagonalis, and Nyctemera baulus. Notably, the abundance of coffee insect pollinators was more pronounced in close proximity to the forest compared to areas far from the forest. Regarding the visiting duration of these insects, S. discolor exhibited the longest visit duration of 76.46±1.19 seconds per flower, and the shortest duration in A. cerana was recorded at 8.35±0.23 seconds per flower.

Interaction network structure explains species' temporal persistence in empirical plant-pollinator communities.

Despite clear evidence that some pollinator populations are declining, our ability to predict pollinator communities prone to collapse or species at risk of local extinction is remarkably poor. Here, we develop a model grounded in the structuralist approach that allows us to draw sound predictions regarding the temporal persistence of species in mutualistic networks. Using high-resolution data from a six-year study following 12 independent plant-pollinator communities, we confirm that pollinator species with more persistent populations in the field are theoretically predicted to tolerate a larger range of environmental changes. Persistent communities are not necessarily more diverse, but are generally located in larger habitat patches, and present a distinctive combination of generalist and specialist species resulting in a more nested structure, as predicted by previous theoretical work. Hence, pollinator interactions directly inform about their ability to persist, opening the door to use theoretically informed models to predict species' fate within the ongoing global change.

Pollinator intraspecific body size variation and sociality influence their interactions with plants

Abstract Species morphological and behavioural traits are key determinants of which pollinator species interact with which plant species. However, individuals within species are not identical in their traits and this diversity could help us understand plant–pollinator interaction patterns. Using three independent data sets, we assessed whether bee intraspecific body size variation (ITV) and sociality influenced pollinator interaction specialisation, intraspecific niche partitioning, centrality in the interaction network and phylogenetic diversity of the plants visited. We found that solitary pollinators were more specialised in their interactions with plants and had lower intraspecific niche partitioning compared to social pollinators. Furthermore, solitary pollinators with higher ITV had higher centrality in the network and visited a higher phylogenetic diversity of plants compared to solitary species with lower ITV, whereas the opposite pattern emerged for social pollinators. Pollinator ITV did not differ between social and solitary bee species. Our findings show that the effect of pollinator body size variation on plant–pollinator interactions depends on pollinator species sociality. Specifically, solitary pollinators with higher ITV and social pollinators with lower ITV seem to be the most important contributors to maintaining the evolutionary diversity of the plant community, and also the species with the largest potential to affect (via cascade effects) the entire plant–pollinator network. Read the free Plain Language Summary for this article on the Journal blog.

Impact of cucurbit crop management techniques on the foraging behavior of honeybees and hoverflies in Morogoro, Tanzania

BackgroundPoor agricultural practices have drastically threatened insect pollinators’ biodiversity. Little is known in Tanzania about how different agricultural practices affect pollinators’ foraging behavior. This study investigated the effects of the agroecological zone, season, cucurbit species and management practices on visitation frequency, visitation rate and time spent on cucurbit flowers by five pollinator species viz. Apis mellifera, Eristalinus megacephalus, Mesembrius caffer, Paragus borbonicus and Toxomerus floralis. The experiment was designed as a 5 × 3 × 3 × 2 × 2 factorial arrangement in a Randomized Complete Block Design (RCBD) with four replications. GAMOUR-Agroecology was tested against conventional practices and untreated control.ResultsThis study revealed significant effects of agroecological zone × season × cucurbit species × management practice on pollinators’ visitation frequency (p = 0.007) and time spent on flowers (p = 0.005). Also, agroecological zone × season × cucurbit species × pollinator species significantly (p < 0.0001) affected pollinators’ visitation frequency. Agroecological zones × season × cucurbit species × cucurbits management practices × pollinators significantly (p = 0.001) affected pollinators’ visitation rate. Apis mellifera was the most frequent visitor in Cucurbita moschata plots treated with GAMOUR- Agroecology in the plateau zone, also, visited higher number of Cucumis sativus plots under GAMOUR-Agroecology practices in the mountainous zone during the October–November season. Furthermore, it has been found that pollinators spent much in cucurbit flowers on plots with GAMOUR-Agroecology practices and control.ConclusionsPollinators’ foraging behavior were enhanced by GAMOUR-Agroecology practices. Therefore, this study recommended that cucurbit growers should consider management practices that positively influence pollinator foraging activities for sustainable cucurbit production.

Drivers of flower visit and resource sharing between the honeybee and native bees in Neotropical coastal sand dunes.

The honeybee (Apis mellifera) is one of the most important pollinator species because it can gather resources from a vast variety of plant species, including both natives and introduced, across its geographical distribution. Although A. mellifera interacts with a large diversity of plants and shares resources with other pollinators, there are some plant species with which it interacts more frequently than others. Here, we evaluated the plant traits (i.e., plant length, abundance of bloomed individuals, number of open flowers, and stamen length) that would affect the honeybee visit frequencies to the flowers in a coastal environment in the Gulf of Mexico. Moreover, we evaluated which native bee species (and their body size) overlap floral resource with A. mellifera. We registered 998 plant-bee interactions between 35 plant species and 47 bee species. We observed that plant species with low height and with high abundances of bloomed individuals are positively related to a high frequency of visits by A. mellifera. Moreover, we found that A. mellifera tends to share a higher number of plant species with other bee species with a similar or smaller body size than with bigger species, which makes them a competitor for the resource with honeybees. Our results highlight that the impacts of A. mellifera on plants and native bees could be anticipated based on its individual's characteristics (i.e., plant height and abundance of bloomed individuals) and body size, respectively.

Adaptive foraging of pollinators fosters gradual tipping under resource competition and rapid environmental change.

Plant and pollinator communities are vital for transnational food chains. Like many natural systems, they are affected by global change: rapidly deteriorating conditions threaten their numbers. Previous theoretical studies identified the potential for community-wide collapse above critical levels of environmental stressors-so-called bifurcation-induced tipping points. Fortunately, even as conditions deteriorate, individuals have some adaptive capacity, potentially increasing the boundary for a safe operating space where changes in ecological processes are reversible. Our study considers this adaptive capacity of pollinators to resource availability and identifies a new threat to disturbed pollinator communities. We model the adaptive foraging of pollinators in changing environments. Pollinator's adaptive foraging alters the dynamical responses of species, to the advantage of some-typically generalists-and the disadvantage of others, with systematic non-linear and non-monotonic effects on the abundance of particular species. We show that, in addition to the extent of environmental stress, the pace of change of environmental stress can also lead to the early collapse of both adaptive and nonadaptive pollinator communities. Specifically, perturbed communities exhibit rate-induced tipping points at stress levels within the safe boundary defined for constant stressors. With adaptive foraging, tipping is a more asynchronous collapse of species compared to nonadaptive pollinator communities, meaning that not all pollinator species reach a tipping event simultaneously. These results suggest that it is essential to consider the adaptive capacity of pollinator communities for monitoring and conservation. Both the extent and the rate of stress change relative to the ability of communities to recover are critical environmental boundaries.

On‐site floral resources and surrounding landscape characteristics impact pollinator biodiversity at solar parks

Abstract There is increasing land use change for solar parks and growing recognition that they could be used to support insect pollinators. However, understanding of pollinator response to solar park developments is limited and empirical data are lacking. We combine field observations with landcover data to quantify the impact of on‐site floral resources and surrounding landscape characteristics on solar park pollinator abundance and species richness. We surveyed pollinators and flowering plants at 15 solar parks across England in 2021, used a landcover map to assess the surrounding high‐quality habitat and aerial imagery to measure woody linear features (hedgerows, woodland edges and lines of trees). In total, 1397 pollinators were recorded, including 899 butterflies (64%), 171 hoverflies (12%), 161 bumble bees (12%), 157 moths (11%), and nine honeybees (&lt;1%). At least 30 pollinator species were observed, the majority of which were common, generalist species. Pollinator biodiversity varied between solar parks and was explained by a combination of on‐site floral resources and surrounding landscape characteristics. Floral species richness was the most influential on‐site characteristic and woody linear feature density generally had a greater impact than the cover of surrounding high‐quality habitats, although drivers differed by pollinator group. Our findings suggest that a range of factors affect pollinator biodiversity at solar parks, but maximising floral resources within a park through appropriate management actions may be the most achievable way to support most pollinator groups, especially where solar parks are located in resource‐poor, disconnected landscapes.

Nature’s reset: The effect of native and invasive plant forage on honey bee nutrition and survival

As a keystone species, honey bees (Apis mellifera) are pollinators that help sustain our food supply and native ecosystems. Unfortunately, habitat loss and widespread pesticide use are major drivers of pollinator decline. In the case of honey bees, rates of infection and colony collapse have been attributed to several interacting factors, including the loss of forage diversity and abundance. In this study, we aimed to investigate the effect of plant forage on bee health across apiaries located in multiple US cities. Hives were divided into healthy green zones, average health yellow zones, and unhealthy red zones. We hypothesized that honey bee colony survival would increase with the number of native plants foraged. Using plant DNA metabarcoding of honey samples, qualitative and quantitative analyses revealed hive health variation due to the population of plants foraged upon. Forage from green zones consisted predominantly of native plants and red zones consisted of primarily invasive plants. Furthermore, hives that were exposed to a natural catastrophic event demonstrated a high percentage of native plant forage post-disaster. Our study represents the first investigation of the significance of native and invasive plant forage to overwintering survival for honey bees as well as novel research examining the effect of natural catastrophic events on honey bee foraging. The availability of native and invasive plants plays a critical role in bee health, performance, and fitness, particularly in post-catastrophic event landscapes. By further understanding the unique dynamics between the type of plant forage and honey bee survival, we may be another step closer to unlocking the mysteries that may benefit the health of 200,000 other pollinator species.

Diversity, Abundance, and Foraging Behaviour of Insect Pollinators in Litchi (Litchi chinensis Sonn.) under Hot and Subhumid Conditions

Insect pollinators and flowering plants have a long‐standing, coevolutionary, mutualistic relationship. One such example is the litchi tree (Litchi chinensis Sonn.), a fruit crop that relies on insect pollination. Litchi flowers are hermaphroditic, but they cannot self‐pollinate due to self‐sterility, unlike self‐pollinating plants. Therefore, insect pollinators are crucial to successful fruit development. To understand the pollinator’s foraging behaviour and diversity associated with litchi under hot and subhumid conditions, the present study was conducted on the Shahi variety of litchi at the ICAR‐Research Complex for Eastern Region, Farming System Research Centre for Hill and Plateau, Ranchi (Jharkhand), India. During the flowering period, a total of 19 species of insect pollinators from the orders Hymenoptera, Diptera, Lepidoptera, and Coleoptera were observed visiting litchi inflorescences. Apis mellifera and Apis dorsata were the most dominant pollinator species. Each species displayed distinct characteristics in terms of abundance and diversity. Varied foraging speeds (stay times) were also noted, with A. dorsata (6.94 s) being the fastest and Musca domestica (2.88 s) being the slowest. Pollinator activity was highest in the eastern direction, between 8:00 a.m. and 10:00 a.m. Apis florea had the highest foraging rate (visitation rate) (14.02 flowers visited per minute), followed by Apis mellifera, while Episyrphus taeniops​ had the lowest. Apis species were identified as the most abundant and frequent visitors in litchi orchards.

Pollination biology of Impatiens capensis Meerb. in non-native range.

Pollination biology in the widespread species Impatiens capensis Meerb. has only been studied in America, specifically in zones of the U.S.A. and Canada. In this study, we investigated the pollination biology of I. capensis using an integrative identification approach using morphological and molecular tools in four populations of Northwest Poland. We also determined and compared the functional characteristics of the pollinators of the introduced species from the study sites and the native ones reported, for the latter collecting information from bibliographic sources. Visitors were identified using standard morphological keys, including identifying and classifying insect mouthparts. Molecular identification was carried out using mitochondrial DNA's cytochrome oxidase subunit I (COI). We morphologically identified 20 species of visitors constituted by 17 pollinators and three nectar robbers. DNA barcoding of 59 individuals proved the identification of 18 species (also 18 BINs). The frequency of pollinator species was primarily made up of representatives of both Hymenoptera (75%) and Diptera (21%). The morphological traits, such as the chewing and sucking mouthparts, small and big body height, and robber and pollinator behavior explained mainly the native and introduced visitors' arrangements that allow pollination success. However, to understand the process comprehensively, further investigation of other causalities in pollination success and understanding the diversity of pollinators in outer native ranges are necessary.