Native Wild Bees Research Articles

No wild bees? Don't worry! Non-bee flower visitors are still hard at work: The edge effect, landscape, and local characteristics determine taxonomic and functional diversity in apple orchards

Native pollinators are key to enhancing fruit production in apple orchards and maintaining yield stability through taxonomic and functional diversity. Some studies suggest that the distance to the nearest native forest patch, the edge effect, or apple orchard management, modulate the richness and abundance of pollinators. However, such studies have focused on bees, thereby generating knowledge gaps about non-bee pollinators. This study looks at the taxonomic and functional diversity in central Chile, as well as the abundance of major pollinator groups (native beetles, flies, wild bees, and lepidopterans), and how these are influenced by landscape and apple orchard characteristics. For two seasons, native and managed pollinators were recorded in nine apple orchards with different management approaches (organic vs conventional) and apple varieties (Gala vs Fuji). The taxonomic and functional diversity of major pollinator groups were correlated with distance to the nearest native forest patch. We measured the edge effect on pollinators toward the interior of apple orchards and analyzed the results with one-way ANOVA. Lastly, we associated the diversity and abundance of pollinators with landscape and apple orchards characteristics using GLMM. Excepted managed bees and contrary to the global trend in apple studies, native flies and beetles were the most dominant pollinators, the latter being more abundant at the orchard edge. The distance to the native forest patch was correlated negatively to the functional richness and positively to body temperature, while that same variable influenced the abundance of total native pollinators, beetles, flies, and wild bees. The gala variety was found to attract greater pollinator richness and more wild bees, whereas organic orchards positively influence native flies and conventional orchards attract lepidopterans. Moreover, the number of honey bees influences the abundance of wild bees and lepidopterans. Land intensification practices could decrease the taxonomic and functional diversity of pollinators. Management alternatives like increased landscape heterogeneity or native habitat restoration, could to maintain apple fruit production in space and time.

Honey productivity of plant formations in the Toratau Geopark of the Republic of Bashkortostan

The Republic of Bashkortostan is one of the regions of Russia where historically, there are favorable landscape and climatic conditions for developing the beekeeping industry. The territory of the Toratau Geopark has incredible biodiversity. Bees are pollinators of entomophilous plants, which, in turn, affects the productivity of berry and fruit plants and contributes to the revival of the natural flora of forest resources. However, only 360 thousand hectares of nectar-producing linden are growing in the three-kilometer zone of apiaries, and the rest are located in inaccessible areas of the republic.Unfavorable weather conditions do not allow for productive honey harvesting during the linden blossom period. Hence, the research aimed to determine the honey productivity of plant formations in the territory of the Toratau Geopark. The results of the studies showed that high honey productivity is characterized by gnat’s linden (574.4 kg/ha) and nettle twigs (458.1 kg/ha). Maplewood formation is a source of abundant honey harvesting in the spring period, with honey productivity of the forest type of the gnarly forest - 350.4 kg/ha, prickly-bristled barry forest - 332.3 kg/ha. In early spring, floodplain elm with significant honey productivity (254.3 kg/ha) and bramble elm (252.3 kg/ha) provide supportive honey collection and build-up of bee family strength. The knowledge gained about the honey productivity of plant formations in the study area is a scientific contribution to the rational use of honey resources in the territory of Bashkortostan. Also, these studies help preserve the natural flora of forest resources, optimize the population, expand the range, and maintain the genetic purity of the people of the native Burzyan wild bee (Apis mellifera L.), as well as for obtaining productive honey collections.

A solitary wild bee Megachile oblonga nesting in honey bee wax combs

Recently, native bee fauna has been observed utilising anthropogenic materials as nesting substrates. Here we report the novel observation of a native solitary cavity-nesting bee, Megachile (Hackeriapis) oblonga (Smith, 1879) (Hymenoptera: Megachilidae: Megachilinae) nesting in man-made, but honey bee drawn waxed frames. This represents a unique indirect interaction between the introduced Apis mellifera and native wild bees and adds to growing evidence of how human activities are altering the behaviour of wild bees, with unknown consequences. Our observations here add to knowledge about the flexibility in nesting habits of wild bees and the potential for bees to adopt novel materials to nest in. This may represent adaptive or maladaptive behaviour; it remains to be determined whether humans are presenting wild bees with an increasing number of “ecological traps” as anthropogenic activities limit the availability of natural nesting substrates in the environment.

Native flower strips increase visitation by non-bee insects to avocado flowers and promote yield

Pollination is an essential ecosystem service for pollinator-dependent crops and plant communities. Apis mellifera L. is by far the most commonly used species to obtain this service in agriculture. However, there is growing evidence of the importance for crop yields of the service provided by wild bees and non-bee insect pollinators. Establishing flower resources in agricultural landscapes is a management practice that can increase insect pollinator populations and improve crop yields. We established perennial native flower strips (NFS) in four avocado orchards in central Chile during autumn 2017. We monitored flower visitors and counted newly formed fruits in avocados near and far from NFS in spring 2019, to assess flower visitor groups, flower visitation rates and fruit numbers. Only A. mellifera visited avocado flowers within bees, whereas both the managed A. mellifera and wild bees were the main visitors to the NFS. NFS increased visitation rates to adjacent avocado of flies, and with a trend for the sum of all non-managed flower visitors (i.e. excluding A. mellifera). However, there were no differences in the rates of A. mellifera visitation to avocados near and far from NFS. Avocado fruit numbers were higher among avocados near NFS than among those farther away. This difference could be due to better pollination by the increased visits to avocado flowers by flies or other wild insects. Therefore, NFS could contribute to crop fruit number, as well as conservation of native flora, wild bees and non-bee pollinators on fruit farms in the “Central Chile” biodiversity hotspot.

Five years of citizen science and standardised field surveys in an informal urban green space reveal a threatened Eden for wild bees in Brussels, Belgium

Abstract Urbanisation is often put forward as an important driver of biodiversity loss, including for pollinators such as wild bees. However, recent evidence shows that the mosaics of urban green spaces, and in particular certain categories of informal urban green spaces (IGS), can play an important role to help native wild bees thrive in cities. Here, we describe the results of 5 years of citizen science and standardised field surveys of wild bees conducted at the Friche Josaphat, a 24‐ha urban wasteland in the Brussels‐Capital Region (Belgium). These field surveys were initiated following the planned restructuring and partial destruction of this site by the regional authorities. We recorded a total of 2507 specimens belonging to 127 species of wild bees, i.e. 60.5% of the 210 species recorded regionally, including nine that are threatened with extinction at national or European scales. The Friche Josaphat encompasses a significant share of the functional and phylogenetic diversity of wild bees known from the Brussels‐Capital Region and is one of the most species‐rich localities known to date for wild bees in Belgium. Collectively, our results highlight the strong complementarity of citizen science and academic approaches in biodiversity surveys, and they reaffirm that wastelands are essential components of urban biodiversity. Our study stresses the need to provide biodiverse IGS with a formal status within the mosaic of urban green spaces but also to acknowledge and safeguard their natural capital and the multiple ecosystem services they provide.

Nesting, Sex Ratio and Natural Enemies of the Giant Resin Bee in Relation to Native Species in Europe.

Simple SummaryAlien bee species could have detrimental effects; in particular, they may compete with native bee species for floral resources or nesting sites. Here, we first studied the interaction in artificial trap nests, installed in a semi-urban area of north-western Italy, between the first exotic bee in Europe, Megachile sculpturalis, and native wild bees. Second, we evaluated the performance of the exotic bee by means of the sex ratio, and we screened for the presence of natural enemies affecting its brood. Our results showed that M. sculpturalis brood cells cohabited tunnels with the native Osmia cornuta. Given the exotic cells’ position within tunnels and their resin-based material, exotic cells may act as a block for native bee emergence. Moreover, our study revealed a strong male-biased sex ratio, suggesting a suboptimal reproductive trend for the M. sculpturalis local population. Additionally, we documented for the first time the presence of three natural enemies on the brood of the exotic bee that are common on native co-nesting bees. These novel findings broaden the knowledge on solitary bee invasions.Megachile sculpturalis (Smith, 1853) is the first exotic bee species in Europe. Its remarkably fast expansion across this continent is leading to a growing concern on the extent of negative impacts to the native fauna. To evaluate the interactions of exotic bees with local wild bees, we set up trap nests for above-ground nesting bees on a semi-urban area of north-western Italy. We aimed to investigate the interaction in artificial traps between the exotic and native wild bees and to assess offspring traits accounting for exotic bee fitness: progeny sex ratio and incidence of natural enemies. We found that the tunnels occupied by exotic bees were already cohabited by O. cornuta, and thus the cells of later nesting alien bees may block the native bee emergence for the next year. The progeny sex ratio of M. sculpturalis was strongly unbalanced toward males, indicating a temporary adverse population trend in the local invaded area. In addition, we documented the presence of three native natural enemies affecting the brood of the exotic bee. Our results bring out new insights on how the M. sculpturalis indirectly competes with native species and on its performance in new locations.

Examining the public's awareness of bee (Hymenoptera: Apoidae: Anthophila) conservation in Canada

AbstractUnderstanding the general public's knowledge and perceptions of an issue can help drive action on the part of decision‐makers. Such understanding is critical when decision‐makers are faced with multiple stakeholders, which is the case with biodiversity conservation issues. We surveyed the Canadian general public using a telephone questionnaire to assess the level of knowledge and perceptions of native wild bee (Hymenoptera: Apoidea: Anthophila) health and conservation. We found that the general level of bee knowledge among participants was low. Half of participants named the non‐native managed European honeybee (Apis mellifera Linnaeus 1758) as a wild bee, native to Canada. Over two‐thirds of participants stated the provisioning of ecosystem services (ES) is the most important reason to conserve bees. Half of participants thought the Canadian federal and provincial government should be principally responsible for bee conservation. One‐third of participants perceived no personal barriers to bee conservation and nearly one‐quarter stated they did not know how to help bee conservation efforts. Our results highlight that scientific researchers can play an important role in outreach and education and environmental non‐governmental organizations (ENGOs) can take an active lobbying role at the provincial and federal levels with respect to bee conservation.

Are native and non-native pollinator friendly plants equally valuable for native wild bee communities?

Bees rely on floral pollen and nectar for food. Therefore, pollinator friendly plantings are often used to enrich habitats in bee conservation efforts. As part of these plantings, non‐native plants may provide valuable floral resources, but their effects on native bee communities have not been assessed in direct comparison with native pollinator friendly plantings. In this study, we performed a common garden experiment by seeding mixes of 20 native and 20 non‐native pollinator friendly plant species at separate neighboring plots at three sites in Maryland, USA, and recorded flower visitors for 2 years. A total of 3,744 bees (120 species) were collected. Bee abundance and species richness were either similar across plant types (midseason and for abundance also late season) or lower at native than at non‐native plots (early season and for richness also late season). The overall bee community composition differed significantly between native and non‐native plots, with 11 and 23 bee species being found exclusively at one plot type or the other, respectively. Additionally, some species were more abundant at native plant plots, while others were more abundant at non‐natives. Native plants hosted more specialized plant–bee visitation networks than non‐native plants. Three species out of the five most abundant bee species were more specialized when foraging on native plants than on non‐native plants. Overall, visitation networks were more specialized in the early season than in late seasons. Our findings suggest that non‐native plants can benefit native pollinators, but may alter foraging patterns, bee community assemblage, and bee–plant network structures.

The melittofauna and its floral associations in a natural riparian forest in Buenos Aires province, Argentina

This study estimates the diversity, abundance and floral associations of native wild bees present in a nature reserve in Buenos Aires, Argentina. The study included monthly sampling from September to April for two consecutive seasons (2011–2013). Bees were collected using entomological nets and pan traps along transects in the reserve area. A total of 1102 specimens belonging to 87 wild bee species/morphospecies in 37 genera of five families were collected. The families with the highest numbers of species were Apidae, followed by Halictidae and Megachilidae. A total of 63 species/morphospecies of plants belonging to 20 families were visited by bees. Asteraceae received the most visits, followed by Fabaceae and Onagraceae. Wild bee/plant interactions were studied through niche breadth and niche overlap. The highest values for niche breadth were found in two social species (Bombus pauloensis and Augochlora amphitrite) and niche overlap was predominantly low among bee species. Our results suggest that the nature reserve “Reserva Natural Integral Punta Lara” in northeastern Buenos Aires Province, Argentina, is an important natural area that supports a diverse community of wild bees.

Attracting Native Bees to Your Florida Landscape

Florida is home to approximately 315 species of native wild bees. These bees rely on flowers for survival; their diets consist exclusively of pollen and nectar harvested from flowers. Recently reported declines in some bee species have heightened awareness of bee conservation across the United States and motivated efforts to increase floral resources for bees. This 7-page fact sheet written by Rachel E. Mallinger, Wayne Hobbs, Anne Yasalonis, and Gary Knox and published by the UF/IFAS Entomology and Nematology Department shows how gardeners and land managers can aid in conservation efforts by planting flowers for bees in home or community gardens. http://edis.ifas.ufl.edu/IN1255

Synergistic effects of three sterol biosynthesis inhibiting fungicides on the toxicity of a pyrethroid and neonicotinoid insecticide to bumble bees

Understanding how different pesticides influence bee health is inhibited by a limited knowledge about the interactions between different compounds to which bees are simultaneously exposed. Although research has demonstrated synergistic effects of some sterol biosynthesis inhibiting (SBI) fungicides on the toxicity of certain insecticides to bees, a high degree of variability exists in the relatively few SBI fungicide-insecticide interactions tested. Furthermore, most research has been conducted on honey bees, Apis mellifera, limiting our understanding of pesticide synergisms in native wild bees. We tested the effects of the SBI fungicides difenoconazole, myclobutanil, and fenhexamid on acute contact toxicity of the insecticides thiamethoxam (neonicotinoid) and bifenthrin (pyrethroid) to the common eastern bumble bee, Bombus impatiens. Based on range-finding trials, we selected a single dosage of each pesticide, with insecticides approximating LD20 values and fungicides approximating their maximum sublethal levels. We found that the triazole SBI fungicide difenoconazole interacted synergistically with bifenthrin, with a maximum synergy ratio of 1.48, while the triazole myclobutanil interacted synergistically with both bifenthrin and thiamethoxam, with maximum synergy ratios of 11.0 and 2.38, respectively. However, the hydroxyanilide SBI fungicide fenhexamid did not exhibit a synergistic effect on either insecticide. Our results suggest that certain SBI fungicides, and potentially those from particular SBI classes, may be particularly harmful to bumble bee health when co-exposure to insecticides occurs, despite their low toxicity when experienced in isolation.

Biodiversity of wild alfalfa pollinators and their temporal foraging characters in Hexi Corridor, Northwest China

Seed production of alfalfa (Medicago sativa L.) is important in determining the effective distribution of new cultivars to farmers. However, little is known about the biodiversity and their community function of native wild pollinators of alfalfa in agronomic systems. We investigated the biodiversity of insects which visited alfalfa flowers and their temporal foraging characters in Hexi Corridor, China. A high biodiversity of insect visitors was discovered, 20 insect taxa in all, including 13 species of Hymenoptera, 3 species of Coleoptera, 3 species of Lepidoptera and 1 species of Diptera. Three native bee species, Andrena squamata, Anthophora melanognatha and Megachile abluta,were validated as the principal pollinators. They showed significant variations in tripping mode and their diurnal distribution patterns. Our results indicated that the native wild bees are diverse and they complement each other. This means they have developed a more complex system for the pollination of alfalfa than has been previously found out.

Pollinator Gardens and Generated Insect Activity

Neonicotinoids are a common pesticide that have harmful effects on pollinators, contributing to their global population decline. Studies have suggested neonicotinoids are more harmful on native bee populations than on European honey bees. The majority of food crop pollination is not provided by European honey bees, however, but by native wild bee populations; specifically, mason (genus Osmia) and bumble bees (genus Bombus). To help sustain and increase local pollinator populations, a pollinator garden was installed using plants native to West Virginia. While the focus of plant pollination is primarily concerning the order Hymenoptera (bees and wasps), this focus neglects other common pollinating invertebrates in the orders Lepidoptera (moths and butterflies), Diptera (flies), and Coleoptera (beetles). Though their pollination capabilities are not as abundant as native bees, they are still an integral part of a garden’s pollination process. We included a variety of plants with varying colors, blood times, and pollinator needs to ensure the largest pollinator attraction possible. One insect hotel has been installed to provide natural housing materials for solitary bees, butterflies and various beneficial insects like lady bugs and lacewings. Non-pollinating invertebrates have a beneficial impact on keeping gardens pest free from detrimental insects. Our goal is to increase pollinators and beneficial insect populations; benefiting both the garden and the native pollinators. We hope to educate students, faculty, staff, and campus visitors on the benefits of installing their own native plant pollinator gardens as well as raise awareness of the growing issue of worldwide food production and the effects of pesticides on local insect populations.

A Review of Native Wild Bee Nutritional Health

Declines in wild and managed bee species richness and abundances have been observed throughout Europe and North America in recent decades. These declines have led to questions regarding pollination of wild and cultivated plants. In response to these concerns, efforts towards the conservation of pollinators have been initiated. Part of this conservation effort should be to provide the basic nutritional needs for bees. Nutrition plays one of the most important roles in bee growth, development, and reproduction. There is a large body of information regarding honey bee nutrition, whereas we lack nutritional information on native wild bees. Our knowledge of bumble bee nutritional needs has increased since the introduction of commercial rearing and sale of certain bumble bee species; however, there is still a lack of basic nutritional guidelines such as minimum dietary needs of proteins, amino acids, lipids, and sterols. The large difference in physiology and life history between honey bees and North American wild bees suggests that their nutritional requirements could be quite different.

Controlling the impact of the managed honeybee on wild bees in protected areas

In recent years, conservation biologists have raised awareness about the risk of ecological interference between massively introduced managed honeybees and the native wild bee fauna in protected natural areas. In this study, we surveyed wild bees and quantified their nectar and pollen foraging success in a rosemary Mediterranean scrubland in southern France, under different conditions of apiary size and proximity. We found that high-density beekeeping triggers foraging competition which depresses not only the occurrence (−55%) and nectar foraging success (−50%) of local wild bees but also nectar (−44%) and pollen (−36%) harvesting by the honeybees themselves. Overall, those competition effects spanned distances of 600–1.100 m around apiaries, i.e. covering 1.1–3.8km2 areas. Regardless the considered competition criterion, setting distance thresholds among apiaries appeared more tractable than setting colony density thresholds for beekeeping regulation. Moreover, the intraspecific competition among the honeybees has practical implications for beekeepers. It shows that the local carrying capacity has been exceeded and raises concerns for honey yields and colony sustainability. It also offers an effective ecological criterion for pragmatic decision-making whenever conservation practitioners envision progressively reducing beekeeping in protected areas. Although specific to the studied area, the recommendations provided here may help raise consciousness about the threat high-density beekeeping may pose to local nature conservation initiatives, especially in areas with sensitive or endangered plant or bee species such as small oceanic islands with high levels of endemism.

FLOWERING PLANTS PREFERRED BY NATIVE WILD BEES (HYMENOPTERA, APOIDEA, APIFORMES) IN THE ALGERIAN LITTORAL REGION

This study considered the plant floral resources visited by native wild and honey bees in Algiers (northern Algeria). Three botanical families accounted for almost 2/3 of all visits: Asteraceae (44.1%), Boraginaceae (15.3%) and Brassicaceae (13%). Plants in other families were visitedless frequently (e.g.Ranunculaceae (0.1%)). At the species level, the most frequently visited plant was Anchusa azurea (Boraginaceae), reaching 15.2% of the total bee visitation. Our work showed that Apis mellifera Linnaeus, 1758 is, typically, a polylectic species and that the majority of solitary bees exhibited the more specialised trait of oligolectics. The narrowest trophic niche varied between 0.01 and 0.06 bits for Halictus rufipes (Fabricius, 1793), Halictus scabiosae (Rossi, 1790) (Halictidae), Osmia pinguis Perez, 1895 and Osmia tricornis Linnaeus, 1811 (Megachilidae).

Do managed bees have negative effects on wild bees?: A systematic review of the literature.

Managed bees are critical for crop pollination worldwide. As the demand for pollinator-dependent crops increases, so does the use of managed bees. Concern has arisen that managed bees may have unintended negative impacts on native wild bees, which are important pollinators in both agricultural and natural ecosystems. The goal of this study was to synthesize the literature documenting the effects of managed honey bees and bumble bees on wild bees in three areas: (1) competition for floral and nesting resources, (2) indirect effects via changes in plant communities, including the spread of exotic plants and decline of native plants, and (3) transmission of pathogens. The majority of reviewed studies reported negative effects of managed bees, but trends differed across topical areas. Of studies examining competition, results were highly variable with 53% reporting negative effects on wild bees, while 28% reported no effects and 19% reported mixed effects (varying with the bee species or variables examined). Equal numbers of studies examining plant communities reported positive (36%) and negative (36%) effects, with the remainder reporting no or mixed effects. Finally, the majority of studies on pathogen transmission (70%) reported potential negative effects of managed bees on wild bees. However, most studies across all topical areas documented the potential for impact (e.g. reporting the occurrence of competition or pathogens), but did not measure direct effects on wild bee fitness, abundance, or diversity. Furthermore, we found that results varied depending on whether managed bees were in their native or non-native range; managed bees within their native range had lesser competitive effects, but potentially greater effects on wild bees via pathogen transmission. We conclude that while this field has expanded considerably in recent decades, additional research measuring direct, long-term, and population-level effects of managed bees is needed to understand their potential impact on wild bees.

Honey bees are the dominant diurnal pollinator of native milkweed in a large urban park.

In eastern North America, the field milkweed, Asclepias syriaca L. (Asclepiadaceae), is used in planting schemes to promote biodiversity conservation for numerous insects including the endangered monarch butterfly, Danaus plexippus (Linnaeus) (Nymphalidae). Less is known about its pollinators, and especially in urban habitats where it is planted often despite being under increasing pressure from invasive plant species, such as the related milkweed, the dog‐strangling vine (DSV), Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae). During the A. syriaca flowering period in July 2016, we surveyed bees in open habitats along a DSV invasion gradient and inspected 433 individuals of 25 bee species in 12 genera for pollinia: these were affixed to bees that visited A. syriaca for nectar and contain pollen packets that are vectored (e.g., transferred) between flowers. Of all bees sampled, pollinia were found only on the nonindigenous honeybee, Apis mellifera (43% of all bees identified), as well as one individual bumblebee, Bombus impatiens Cresson. Pollinia were recorded from 45.2% of all honeybees collected. We found no relationship between biomass of DSV and biomass of A. syriaca per site. There was a significant positive correlation between A. syriaca biomass and the number of pollinia, and the proportion vectored. No relationship with DSV biomass was detected for the number of pollinia collected by bees but the proportion of vectored pollinia declined with increasing DSV biomass. Although we find no evidence of DSV flowers attracting potential pollinators away from A. syriaca and other flowering plants, the impacts on native plant–pollinator mutualisms relate to its ability to outcompete native plants. As wild bees do not appear to visit DSV flowers, it could be altering the landscape to one which honeybees are more tolerant than native wild bees.

Gamma irradiation of pollen and eradication of Israeli acute paralysis virus

Honeybees and bumblebees are the most important pollinators of agricultural crops. For this purpose honeybees and bumblebees are reared and transported. A pathogen-free status of bees in general, is crucial. Indeed anthropogenic transports of hosts carrying parasites could alter the natural host/pathogen association, inducing an extra pathogenic stress. Therefore the creation of a pathogen-free rearing environment is needed. For bumblebees this is possible, as these species are reared in a closed environment. Although, a link remains between reared bumblebees and the outside bee community, as honeybee-collected pollen is essential food for bumblebee mass rearing. Here we evaluated if gamma irradiation can minimize the risk of this potential route of exposure and can inactivate viral particles present in honeybee-collected pollen. We show that 16.9kGy gamma irradiation induced a 100–1000 fold reduction on the ability of IAPV to cause mortality after injections. This result opens avenues toward rearing pathogen-free bumblebees and towards eliminating the risks of pathogen spillover to native wild bee species.

Contrasting responses of hoverflies and wild bees to habitat structure and land use change in a tropical landscape (southern Yunnan, SW China)

Abstract The response of insects to monoculture plantations has mainly proceeded at the expense of natural forest areas, and is an outstanding and important issue in ecology and conservation biology, with pollination services declined around the world. In this study, species richness and distribution of hoverfly and wild bee communities were investigated in a changing tropical landscape in southern Yunnan, south‐west China by Malaise traps periodically from 2008 to 2009. Species were recorded from the traditional land use types (natural forest, grassland, shrubland and rice field fallows), and from recently established rubber plantations of different ages. Hoverflies (total 53 species) were most common in young successional stages of vegetation, including rice field fallow and shrubland. Species richness was highest in rice field fallows and lowest in forests and showed a highly significant relationship with the number of forb species and ground vegetation cover. In contrast, the highest richness of wild bees (total 44 species) was recorded from the natural forest sites, which showed a discrete bee community composition compared to the remaining habitat types. There was no significant relationship between the bee species richness and the environmental variables, including the numbers of different plant life forms, coverage of canopy and ground vegetation, successional age of vegetation and land use type. At the landscape scale, open land use systems, including young rubber plantations, are assumed to increase the species richness of hoverflies; however, this might decrease wild bee diversity. The present land use change by rubber cultivation can be expected to have negative impacts on the native wild bee communities.