Bee Diversity and some Aspects of their Ecological Interactions with Plants in a Successional Tropical Community

This study aimed at establishing bee diversity and some aspects of their interactions with plants along a forest regeneration gradient in Kakamega Forest. To determine the bee diversity, bee samples were collected with the help of sweep nets along belt transects for a period of two years, that is, May 2002 to April 2004. In addition, more data on bee species was collected from the existing past records and bee collections from National Museums of Kenya. In total, 243 species of bees represented in four families, of which 234 were sampled in Buyangu Nature Reserve were recorded during the study. These families included Apidae, Halictidae, Megachilidae and Colletidae. In addition, 40 families of representing 189 species of plants were found to support the bee community. The most important plant families included Acanthaceae, Asteraceae and Papilionaceae. A high degree of resource sharing based on niche overlap results was observed between the highly eusocial and the dominant solitary bee species, although the eusocial bees showed the largest niche breadth. Similarly, generalization was more pronounced among the eusocial bees as compared to solitary bees. The results from this study agreed with the expected trend of increased diversity in secondary forests as compared to mature forests. In contrast, generalization was found to increase with forest maturity. In conclusion, the study clearly indicates that bees require a diversity of microhabitats. Secondary forests and surrounding farming areas offer the best refugia sites for bees. On the other hand, the bees cannot survive without the forest for it offers nesting sites and abundant floral resources especially during the dry season when there are no flowers in the open areas. Based on the current results, Kakamega Forest stands out as one of the best bee hot-spots in East Africa. The study advocates further research in pollination biology of wild plants especially on rare plants given that a high level of generalization was documented among the eusocial and solitary bees but little is known on plants’ perspective. Finally, I wish to recommend further research on whether natural forest regeneration process should be altered in some forest patches in order to maintain some secondary forests

Bee diversity and floral resources along a disturbance gradient in Kaya Muhaka forest and surrounding farmlands of coastal Kenya

Bees provide important pollination services that maintain native plant populations and ecosystem resilience, which is critical to the conservation of the rich and endemic biodiversity of Kaya forests along the Kenyan Coast. This study examined bee composition and floral resources from the forest core to the surrounding farmlands around Kaya Muhaka forest. In total, 755 individual bees, representing 41 species from three families were recorded: Apidae, Halictidae and Megachilidae. Overall, Apidae were the most abundant with a proportion of 76% of the total bee individuals, Halictidae at 14% and Megachilidae at 10%. Bee composition was similar between forest edge and crop fields as compared to forest core and fallow farmlands. We found a significant decrease in bee diversity with increasing distance from the forest to the surrounding farming area. A high abundance of bees was recorded in fallow farmland, which could be explained by the high abundance of floral resources in the habitat. We found floral resources richness to significantly affect bee species richness. These findings are important for understanding the effects of land use change on insect pollinators and their degree of resilience in disturbed habitat

Aspects determining the risk of pesticides to wild bees: risk profiles for focal crops on three continents

In order to conduct a proper risk assessment of pesticides to bees, information is needed in three areas: the toxicity of the pesticide;the probability of bee exposure to that pesticide; andthe population dynamics of the bee species in question.Information was collected on such factors affecting pesticide risk to (primarily wild) bees in several crops in Brazil, Kenya and The Netherlands. These data were used to construct ‘risk profiles’ of pesticide use for bees in the studied cropping systems. Data gaps were identified and potential risks of pesticides to bees were compared between the crops. Initially, risk profiling aims to better identify gaps in our present knowledge. In the longer term, the established risk profiles may provide structured inputs into risk assessment models for wild and managed bees, and lead to recommendations for specific risk mitigation measures. Keywords: pesticide, exposure, risk, wild bees, risk profil

Biocultural approaches to pollinator conservation

Pollinators underpin sustainable livelihoods that link ecosystems, spiritual and cultural values, and customary governance systems with indigenous peoples and local communities (IPLC) across the world. Biocultural diversity is a short-hand term for this great variety of people-nature interlinkages that have developed over time in specific ecosystems. Biocultural approaches to conservation explicitly build on the conservation practices inherent in sustaining these livelihoods. We used the Conceptual Framework of the Intergovernmental Platform on Biodiversity and Ecosystem Services to analyse the biocultural approaches to pollinator conservation by indigenous peoples and local communities globally. The analysis identified biocultural approaches to pollinators across all six elements of the Conceptual Framework, with conservation-related practices occurring in sixty countries, in all continents except Antarctica. Practices of IPLC that are significant for biocultural approaches to pollinator conservation can be grouped into three categories: the practice of valuing diversity and fostering biocultural diversity; landscape management practices; and diversified farming systems. Particular IPLCs may use some or all of these practices. Policies that recognise customary tenure over traditional lands, strengthen Indigenous and Community Conserved Areas, promote heritage listing and support diversified farming within a food sovereignty approach, are among several identified that strengthen biocultural approaches to pollinator conservation, and thereby deliver mutual benefits for pollinators and people

Investigating the Viral Ecology of Global Bee Communities with High-Throughput Metagenomics

Bee viral ecology is a fascinating emerging area of research: viruses exert a range of effects on their hosts, exacerbate the impacts of other environmental stressors, and, importantly, are readily shared across multiple bee species in a community. However, our understanding of bee viral communities is limited, as it is primarily derived from studies of North American and European Apis mellifera populations. Here, we examined viruses in populations of A. mellifera and 11 other bee species from 9 countries, across 5 continents and Oceania. We developed a novel pipeline to rapidly, inexpensively, and robustly screen for bee viruses. This pipeline includes purification of encapsulated RNA/DNA viruses, sequence-independent amplification, high throughput sequencing, integrated assembly of contigs, and filtering to identify contigs specifically corresponding to viral sequences. We identified sequences corresponding to (+)ssRNA, (-)ssRNA, dsRNA, and ssDNA viruses. Overall, we found 127 contigs corresponding to novel viruses (i.e. previously not observed in bees), with 29 represented by \u3e0.1% of the reads in a given sample. These viruses and viral families were distributed across multiple regions and species. This study provides a robust pipeline for metagenomics analysis of viruses, and greatly expands our understanding of the diversity of viruses found in bee communities

Bee diversity along a forest regeneration gradient in Western Kenya

Gikungu M, Wittmann D, Irungu D, Kraemer M. Bee diversity along a forest regeneration gradient in Western Kenya. Journal of Apicultural Research. 2011;50(1):22-34.Changes in bee species richness and diversity were studied along a forest regeneration gradient in seven sites in Buyangu Nature Reserve, Kakamega Forest, Kenya. At each site, 12 belt transects of 100 m length and 2 m width were established. The selected sites ranged from relatively undisturbed primary to late secondary forests, bush lands and the surrounding farming areas. A total of 4,485 individuals were identified out of 234 species of bee in four families. A Renyi Diversity Index was used to analyse bee diversity. One-way measures of ANOVA were calculated for bee diversity and species richness, with study sites and year as independent factors. The highest species richness and bee diversity were recorded in the open areas followed by secondary forests while evenness was higher in forested sites. There was a general similarity between sites in bee species composition, especially between those of almost similar vegetation structure. This similarity was suspected to have important implications in promoting current understanding of ecological resilience of bees in tropical ecosystems. The study concludes that the future of forest biodiversity and pollination services are dependent on strategic and holistic management of natural forests, secondary forests and the neighbouring agro-ecosystems

Bee diversity and floral resources along a disturbance gradient in Kaya Muhaka forest and surrounding farmlands of coastal Kenya

Article abstractKaya forests are rich in biodiversity and endemism along the coastal ecosystems of Kenya. The role of bees in pollination service that maintains native plant populations and resilience of such critical ecosystems is unprecedented. This study examined the diversity and floral resources for bees in Kaya Muhaka forest, forest edge, surrounding fallow farmlands and crop fields along a disturbance gradient with aim of informing local conservation and livelihood projects. In total, 755 individual bees, representing 52 species were recorded. Families; Apidae, Halictidae and Megachilidae were recorded. Overall, Apidae were most abundant with a proportion of 76%, Halictidae at 14% and Megachilidae at 10%. Bee composition was closely similar between forest edge and crop fields as compared to other habitats. However, bee diversity did not change significantly with increasing distance from the forest to surrounding farmlands, a pointer to high resilience of bee species. High abundance of bee populations was recorded in fallow farmlands, explained by high abundance of floral resources in the habitat. We noted a significant effect of floral resources richness on bee species richness. We compare these results to several recent bee faunal surveys including surveys in other parts of East Africa, Europe and Asia. These findings are important for understanding the effects of land use change on bee populations for effective conservation planning.Kaya forests are rich in biodiversity and endemism along the coastal ecosystems of Kenya. The role of bees in pollination service that maintains native plant populations and resilience of such critical ecosystems is unprecedented. This study examined the diversity and floral resources for bees in Kaya Muhaka forest, forest edge, surrounding fallow farmlands and crop fields along a disturbance gradient with aim of informing local conservation and livelihood projects. In total, 755 individual bees, representing 52 species were r ecorded. Families; Apidae, Halictidae and Megachilidae were recorded. Overall, Apidae were mo st abundant with a proportion of 76%, Halictidae at 14% and Megachilidae at 10%. Bee comp osition was closely similar between forest edge and crop fields as compared to other habitats. However, bee diversity did not change significantly with increasing distance from the for est to surrounding farmlands, a pointer to high resilience of bee species. High abundance of bee po pulations was recorded in fallow farmlands, explained by high abundance of floral resources in the habitat. We noted a significant effect of floral resources richness on bee species richness. We compare these results to several recent bee faunal surveys including surveys in other parts of East Africa, Europe and Asia. These findings are important for understanding the effects of land use change on bee populations for effective conservation planning