Bee conservation

Due to the contribution of honey bees (Apis mellifera) to wild flower and crop pollination, beekeeping has traditionally been considered a sustainable practice. However, high honey bee densities may have an impact on local pollen and nectar availability, which in turn may negatively affect other pollinators. This is exacerbated by the ability of honey bees to recruit foragers to highly rewarding flower patches. We measured floral resource consumption in rosemary (Rosmarinus officinalis) and thyme (Thymus vulgaris) in 21 plots located at different distances from apiaries in the scrubland of Garraf Natural Park (Barcelona), and related these measures to visitation rates of honey bees, bumblebees (Bombus terrestris) and other pollinators. In the same plots, we measured flower density, and used pan traps to characterize the wild bee community. Flower resource consumption was largely explained by honey bee visitation and marginally by bumblebee visitation. After accounting for flower density, plots close to apiaries had lower wild bee biomass. This was due to a lower abundance of large bee species, those more likely to be affected by honey bee competition. We conclude that honey bees are the main contributors to pollen/nectar consumption of the two main flowering plants in the scrubland, and that at the densities currently occurring in the park (3.5 hives / km 2) the wild bee community is being affected. Our study supports the hypothesis that high honey bee densities may have an impact on other pollinators via competition for flower resources. Zusammenfassung Wegen des Beitrages der Honigbiene (Apis mellifera) bei der Bestäubung von Wildblumen und Nutzpflanzen wurde die Bienenhaltung traditionell als eine nachhaltige Aktivität angesehen. Indessen können hohe Honigbienendichten Auswirkungen auf die lokale Verfügbarkeit von Nektar und Pollen haben, was wiederum andere Bestäuber negativ beeinflussen könnte. Dies wird verstärkt durch die Fähigkeit der Honigbiene, Sammlerinnen zu lohnenden Sammelstellen zu dirigieren. Im Buschland des Garraf-Naturparks bei Barcelona maßen wir den Verbrauch von Blütenressourcen an Rosmarin (Rosmarinus officinalis) und Thymian (Thymus vulgaris) an 21 Standorten, die unterschiedlich weit von Bienenständen entfernt lagen, und setzten diese Werte in Bezug zu den Besuchsraten von Honigbienen, Hummeln (Bombus terrestris) und sonstigen Bestäubern. An den gleichen Standorten bestimmten wir die Blütendichte und setzten A c c e p t e d m a n u s c r i p t Farbschalen ein, um die Wildbienengemeinschaft zu erfassen. Die Nutzung der Blüt enressou wurde weitgehend durch die Besuchsraten der Honigbiene erklärt und in geringfügigem Maße durch Hummelbesuch. Nach Berücksichtigung der Blütendichte wiesen Standorte in der Nähe von Bienenständen eine geringere Wildbienen-Biomasse auf. Dies war auf eine geringere Abundanz der großen Wildbienenarten zurückzuführen, also der Arten, die wahrscheinlich durch die Konkurrenz der Honigbiene beeinträchtigt werden. Wir schließen, dass Honigbienen den größten Beitrag zum Pollen-bzw. Nektarverbrauch bei den beiden wichtigsten Blütenpflanzen des Gebietes leisten und dass die Wildbienengemeinschaft bei den gegenwärtigen Honigbienendichten im Park (3.5 Völker/km²) beeinflusst wird. Unsere Untersuchung unterstützt die Hypothese, dass hohe Honigbienendichten durch Konkurrenz um Blütenressourcen einen Einfluss auf andere Bestäuber haben könnten.

The availability of floral resources is considered a key factor for the maintenance and conservation of pollinators. We compared the forage floral diversity of three types of lowland meadows (Molinia meadows, tall herb fringe meadows, and hay meadows) located in south eastern Poland. The total number of plant species was 125, including 84 species (67.2%) classified as plants visited by insects. The richness and diversity of forage flora differed between the types of meadow. The Molinia meadows and hay meadows were preferred by pollinators. However, different taxonomic groups of pollinators can respond to the variability and availability of floral resources in a different way. Molinia meadows are of particular importance for the abundance of Bombus spp., solitary bees, and flies. The RDA ordination model demonstrated that the floral community composition, plant species abundance, plant species richness, and floral attributes (size, shape, phenology) were all important for the abundance of insect visitors in the mosaic of meadows. The cluster analysis showed that most plant species were visited by similar groups of insects; however, their proportion differed considerably. Our results present arguments for inclusion of semi-natural meadows into conservation plans and for efforts of protection of highly effective floral resources aimed at maintenance of pollinators. Disponibilidad de recursos alimentarios para los polinizadores en tres tipos de praderas de tierras bajas La disponibilidad de recursos florales se considera un factor clave para el mantenimiento y conservació n de los polinizadores. Comparamos la diversidad floral forrajera de tres tipos de praderas de tierras bajas (praderas de Molinia, praderas de hierbas altas y praderas de heno) localizadas en el sureste de Polonia. El número total de especies de plantas fue de 125, incluyendo 84 especies (67.2%) clasificadas como plantas visitadas por insectos. La riqueza y diversidad de la flora forrajera difiere según el tipo de pradera. Los prados de Molinia y los prados de heno fueron preferidos por los polinizadores. Sin embargo, diferentes grupos taxonó micos de polinizadores pueden responder a la variabilidad y disponibilidad de recursos florales de una manera diferente. Las praderas de Molinia son de particular importancia para la abundancia de Bombus spp., abejas solitarias y moscas. El modelo de ordenació n RDA demostró que la composició n de la comunidad floral, la abundancia de especies de plantas, la riqueza de especies de plantas y los atributos florales (tamaño, forma, fenología) eran todos importantes para la abundancia de visitantes de insectos en el mosaico de praderas. El análisis de clúster mostró que la mayoría de las especies de plantas fueron visitadas por grupos similares de insectos; sin embargo, su proporció n difirió considerablemente. Nuestros resultados presentan argumentos para la inclusió n de praderas seminaturales en los planes de conservació n y para los esfuerzos de protecció n de recursos florales altamente efectivos destinados al mantenimiento de polinizadores.

Bees ensure 35 % of global food production, but this service is endangered due to several threats. Declines in bumblebee populations (genus Bombus) have been reported worldwide. Bombus bellicosus is one of the rare cases of reported threatened bumblebees in South America. It was once widespread in southern Brazil's grasslands until the 1960s. During that time, that area underwent increasing land use which led to a decrease in bee abundance and richness, and to local disappearance of B. bellicosus. Climate change is also believed to cause declines in the abundance of B. bellicosus. Here we used species distribution models to assess potential effects of climate changes on the distribution of B. bellicosus in southern Brazil, considering both current and future climate scenarios. Our results show that the suitable climatic conditions for B. bellicosus will retreat southwards. A wax cover inside its nests is usually related to Bombus species inhabiting cooler climates. This cover enables the maintenance of higher temperatures inside the nest and may be deleterious for the species under future warmer climates. Continuously growing land use is the second major threat to this pollinator. The results presented here may eventually provide theoretical grounds and enable practical conservation actions for B. bellicosus protection in South America, especially given the potential adverse effects of climate changes for this species.

The flora inventory was carried out in 2011-2012 in the Jastkow manicipality in SE part of Poland. The aim of the study was to assign the condition of bee flora and establish the floristic richness on fallows, bush communities and fields margins in agricultural landscape. Flora of these biotops consists of 214 species, among them 80% were flow taxons. Apophytes (163 species – 78%) predominated on all types of biotops under consideration. Perennials predominated in flora of boundary strips and bush communities. Mainly hemicryptophytes and therophytes compose flora of fallows. Great number of plant taxons which are important as food for bee were originated to meadows, segetal or ruderal plants. Most flow plants compose loose patches but its successive blooming ensure source of food for Apoidea, and other pollinators i.e. Diptera, Syrphidae, Lepidoptera, Vespidae, Heteroptera and Coleoptera from early spring till the end of summer. The flora of boundary strips create the biodiversity i...

Understanding the factors that have an impact on the diversity of forage flora in the agricultural landscape is a key issue in the maintenance and control of food niches for pollinators. Field margins are common linear structures in the agricultural landscape. In the present study, we evaluated the factors that exert an impact on the forage flora composition and on the diversity in field margins. The study was conducted in the 2010 - 2011 time period across the agricultural landscape on the Lublin Upland of SE Poland. Data on the forage flora were obtained while making floristic charts along 45 transect plots x 300 m; the total length being 13500 m. Multivariate ordination techniques (PCA and RDA) were employed to analyse forage-flora characteristics. Field margins represent valuable refuge areas for forage-species richness, but not for the abundance of forage species. On field margins, forage-species diversity benefits from the location of natural habitats (forests or meadows), pri...

The availability of floral resources is considered a key factor for the maintenance and conservation of pollinators. We compared the forage floral diversity of three types of lowland meadows (Molinia meadows, tall herb fringe meadows, and hay meadows) located in south eastern Poland. The total number of plant species was 125, including 84 species (67.2%) classified as plants visited by insects. The richness and diversity of forage flora differed between the types of meadow. The Molinia meadows and hay meadows were preferred by pollinators. However, different taxonomic groups of pollinators can respond to the variability and availability of floral resources in a different way. Molinia meadows are of particular importance for the abundance of Bombus spp., solitary bees, and flies. The RDA ordination model demonstrated that the floral community composition, plant species abundance, plant species richness, and floral attributes (size, shape, phenology) were all important for the abundance of insect visitors in the mosaic of meadows. The cluster analysis showed that most plant species were visited by similar groups of insects; however, their proportion differed considerably. Our results present arguments for inclusion of semi-natural meadows into conservation plans and for efforts of protection of highly effective floral resources aimed at maintenance of pollinators. Disponibilidad de recursos alimentarios para los polinizadores en tres tipos de praderas de tierras bajas La disponibilidad de recursos florales se considera un factor clave para el mantenimiento y conservació n de los polinizadores. Comparamos la diversidad floral forrajera de tres tipos de praderas de tierras bajas (praderas de Molinia, praderas de hierbas altas y praderas de heno) localizadas en el sureste de Polonia. El número total de especies de plantas fue de 125, incluyendo 84 especies (67.2%) clasificadas como plantas visitadas por insectos. La riqueza y diversidad de la flora forrajera difiere según el tipo de pradera. Los prados de Molinia y los prados de heno fueron preferidos por los polinizadores. Sin embargo, diferentes grupos taxonó micos de polinizadores pueden responder a la variabilidad y disponibilidad de recursos florales de una manera diferente. Las praderas de Molinia son de particular importancia para la abundancia de Bombus spp., abejas solitarias y moscas. El modelo de ordenació n RDA demostró que la composició n de la comunidad floral, la abundancia de especies de plantas, la riqueza de especies de plantas y los atributos florales (tamaño, forma, fenología) eran todos importantes para la abundancia de visitantes de insectos en el mosaico de praderas. El análisis de clúster mostró que la mayoría de las especies de plantas fueron visitadas por grupos similares de insectos; sin embargo, su proporció n difirió considerablemente. Nuestros resultados presentan argumentos para la inclusió n de praderas seminaturales en los planes de conservació n y para los esfuerzos de protecció n de recursos florales altamente efectivos destinados al mantenimiento de polinizadores.

In a modern agricultural landscape the assurance of food resources is a key issue in the maintaince and control of food niche for pollinators. In the present study we evaluated bee forage flora composition and diversity within railway embankments located in the agricultural landscape, SE Poland. We also analysed the abundance of pollinators that use food resources along railway embankments and recognized insect visitors preference for selected plant species. Railway embankments represent valuable refuge areas for bee forage flora (307 species, i.e. 76.1% of total flora) and pollinators (in total 4172 insect visits from 9 taxonomic groups). However, the richness and abundance of bee forage flora significantly differed between types of the railway distinguished by traffic volume. The highest diversity of bee forage flora is noted along the railway with intermediate traffic volume. Approx. 25% and 40% less bee forage species was identified along railways with low and high traffic volum...

The three-year study on borage was conducted in Lublin, SE Poland. The aims were to investigate the flowering pattern and abundance, and the attractiveness (in terms of nectar and pollen production) for flower-visiting insects, mainly bees. Insect visitation and the effect of pollinators on fruit set and seed set were assessed as well. Flowering of borage started in the latter half of June and lasted eight weeks. The mean number of flowers · m−2 of the crop was 4570 per season. A borage flower produced on average 4.0 mg of nectar with a mean sugar concentration of 31.5%. The mean total sugar amount secreted in nectar was 1.2 mg. The pollen amount · flower−1 was 1.1 mg. A borage plant can supply insects with 1.1 g of nectar sugars and 1.1 g of pollen. The estimated nectar sugar yield and pollen yield per 1 m2 of the crop were similar, i.e. 5.2 g. Bees accounted for 73.0% of all insect visits to the borage flowers. The presence of insect pollinators increased the fruit set by 43.3% an...

Pollen collected from flowers by forager bees is the only natural protein source for the hive. This nutritional compound is fundamental for the nurse bee and brood development, and for the queen activity. Pollen has a strong influence on colony health. It is also known that the pollen quality, in terms of the amino acid profile and total protein content, varies significantly according to the floral origin. For this reason, the palynological diversity assessed in corbicular pollen is a good measure of the quality of the environment the bees live in, in terms of available food. An international research initiative "C.S.I. Pollen" aims to elaborate a pollen diversity map for all of Europe, carried out by beekeepers. Chromatic assessment of pellet colours will be used as a method. In our study, we wanted to validate this idea, through the comparison between the two methods: chromatic assessment of the diversity of pollen pellet colours and palynological assessment of the real pollen type diversity. In other words, we wanted to verify whether the pellet-colour profile reflects the palynological one. We found a significant correlation between results obtained from the two methods but some improvements are also proposed in order to increase the determination coefficient and to reduce the differences given by the two answers.

Plant species diversity is threatened in many agricultural landscapes due to the changes it has to undergo. Although the modification of the agricultural landscape pattern is observed across Europe, both extensive and intensive agricultural landscapes still co-exist in Poland. The objective of the study was to examine the flora in field margins in intensively and extensively managed agricultural landscapes, located across three regions in SE Poland. The flora was compared with respect to species richness, diversity, and evenness indices. Detrended correspondence analysis was employed to characterise variation in species composition. Agricultural landscape type made a higher contribution than the topography or geology to species richness and composition in field margins. Field margins function as important habitats for general vascular plant species diversity and are useful for the conservation of rare, threatened, endangered or bee plants. A significant decline in species diversity ...

The paper indicates the phytocenoses most rich in bee taxons and occurring in habitats located along railway lines crossing Lublin Upland. To date, in the study area 124 basic phytocoenoses have been discovered, described and classifi ed into 12 different synecological groups. Among 52 phytocoenoses, the participation of bee fl ora was considerable. Most voluble phytocoenoses represent ruderal and segetal associations (Artemisietea vulgaris, Stellarietea mediae classes-87 species), meadow and pasture associations (Mollinio-Arrhenatheretea-56 species), psammophilous and xerothermic grasslands (Festuco-Brometea, Koelerio glauce-Corynophoretea canescensis-38 species), thermophilous forest edge communities and thickets (Trifolio-Geranietea and Rhamno-Prunetea-33 species). Signifi cantly fewer melliferous and polleniferous taxons were noticed in mesophilous deciduous forests or thermophilous oak forests-29 species. Most simple in structure and species richness are associations with Rumex acetosa, Reseda lutea, Linaria vulgaris, Papaver rhoeas, Cirsium arvense, Oenothera biennis, Viola arvensis and Potentilletum anserine or Sisymbrietum altissimi. The communities form patches (15-20 m 2) with 80-100% cover of the diagnostic taxon and are of low or medium stability. The most persistent and fl oristically stable are Tanaceto Artemisietum, Rudbeckio-Solidaginetum, Echio-Melilotetum, Sambucetum nigrae, Rubo fruticosi-Prunetum spinosae and communities with Rosa rugosa, Rubus caesius, Geranium robertianum, Pastinaca sativa, Trifolium medium or Euphorbia cyparissias. The maintenance of the mosaic of phytocoenoses in anthropogenically transformed habitats, including those along railway lines, is of decisive importance for the protection of fl oristic diversity and adaptation processes of Apoidea.

Honey bees play a vital role in the pollination of flowers in many agricultural systems, while providing honey through well managed beekeeping activities. Managed honey bees rely on the provision of pollen and nectar for their survival and productivity. Using data from field plot inventories in natural mistbelt forests, we (1) assessed the diversity and relative importance of honey bee plants, (2) explored the temporal availability of honey bee forage (nectar and pollen resources), and (3) elucidated how plant diversity (bee plant richness and overall plant richness) influenced the amount of forage available (production). A forage value index was defined on the basis of species-specific nectar and pollen values, and expected flowering period.

Bees ensure 35 % of global food production, but this service is endangered due to several threats. Declines in bumblebee populations (genus Bombus) have been reported worldwide. Bombus bellicosus is one of the rare cases of reported threatened bumblebees in South America. It was once widespread in southern Brazil's grasslands until the 1960s. During that time, that area underwent increasing land use which led to a decrease in bee abundance and richness, and to local disappearance of B. bellicosus. Climate change is also believed to cause declines in the abundance of B. bellicosus. Here we used species distribution models to assess potential effects of climate changes on the distribution of B. bellicosus in southern Brazil, considering both current and future climate scenarios. Our results show that the suitable climatic conditions for B. bellicosus will retreat southwards. A wax cover inside its nests is usually related to Bombus species inhabiting cooler climates. This cover enables the maintenance of higher temperatures inside the nest and may be deleterious for the species under future warmer climates. Continuously growing land use is the second major threat to this pollinator. The results presented here may eventually provide theoretical grounds and enable practical conservation actions for B. bellicosus protection in South America, especially given the potential adverse effects of climate changes for this species.

A b s t r a c t Understanding the factors that have an impact on the diversity of forage flora in the agricultural landscape is a key issue in the maintenance and control of food niches for pollinators. Field margins are common linear structures in the agricultural landscape. In the present study, we evaluated the factors that exert an impact on the forage flora composition and on the diversity in field margins. The study was conducted in the 2010 -2011 time period across the agricultural landscape on the Lublin Upland of SE Poland. Data on the forage flora were obtained while making floristic charts along 45 transect plots x 300 m; the total length being 13500 m. Multivariate ordination techniques (PCA and RDA) were employed to analyse forage-flora characteristics. Field margins represent valuable refuge areas for forage-species richness, but not for the abundance of forage species. On field margins, forage-species diversity benefits from the location of natural habitats (forests or meadows), primarily if the distance from these habitats is <1000 m or the field acreage is <10 ha. The shift from heterogeneous habitats to a more homogeneous landscape causes a reduction of forage floral diversity. Due to lack of dense forage-species patches, the promotion of sowing nectariferous and/or polleniferous species seems to be a reasonable management method to enhance the quantitative food niche on field margins and to support the conservation of pollinators in the areas surrounding farms.