[Pollinator] [EXTERNAL] Favorite articles/readings - pollination biology

Fri Jan 10 14:11:43 PST 2020

talk about honey vs native bees!

Helpful website
https://www.bee-washing.com/good

honeybee competition… Links to papers

https://onlinelibrary.wiley.com/doi/abs/10.1111/conl.12263
http://science.sciencemag.org/content/359/6374/392
https://www.sciencedirect.com/science/article/pii/S000632071730040X?via%3Dihub
https://www.nature.com/articles/s41559-017-0249-9
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0189268

Cane, J. H. and V. J. Tepedino (2016). "Gauging the effect of honey bee pollen collection on native bee communities." Conservation Letters: n/a-n/a.
    Experimental demonstration of direct exploitative competition between foraging honey bees and native bees in wildlands has proven elusive, due to problems of experimental design, scale, and context-dependence. We propose a different approach that translates floral resources collected by a honey bee colony into progeny equivalents of an average solitary bee. Such a metric is needed by public land managers confronting migratory beekeeper demands for insecticide-free, convenient, resource-rich habitats for summering. We calculate that, from June–August, a strong colony gathers as much pollen as could produce 100,000 progeny of an average solitary bee. Analogous to the animal unit month (AUM) for livestock, a hive unit month (HUM) is therefore 33,000 native bee progeny. By this calculation, a 40-hive apiary residing on wildlands for 3 months collects the pollen equivalent of four million wild bees. We introduce a rapid assessment metric to gauge stocking of honey bees, and briefly highlight alternative strategies to provide quality pasture for honey bees with minimal impact on native bees.

Cane, J. H. and V. J. Tepedino (2017). "Gauging the effect of honey bee pollen collection on native bee communities." Conservation Letters 10(2): 205-210.
    Experimental demonstration of direct exploitative competition between foraging honey bees and native bees in wildlands has proven elusive, due to problems of experimental design, scale, and context-dependence. We propose a different approach that translates floral resources collected by a honey bee colony into progeny equivalents of an average solitary bee. Such a metric is needed by public land managers confronting migratory beekeeper demands for insecticide-free, convenient, resource-rich habitats for summering. We calculate that, from June–August, a strong colony gathers as much pollen as could produce 100,000 progeny of an average solitary bee. Analogous to the animal unit month (AUM) for livestock, a hive unit month (HUM) is therefore 33,000 native bee progeny. By this calculation, a 40-hive apiary residing on wildlands for 3 months collects the pollen equivalent of four million wild bees. We introduce a rapid assessment metric to gauge stocking of honey bees, and briefly highlight alternative strategies to provide quality pasture for honey bees with minimal impact on native bees.

Geldmann, J. and J. P. González-Varo (2018). "Conserving honey bees does not help wildlife." Science 359(6374): 392-393.

Goras, G., et al. (2016). Impact of honeybee (Apis mellifera L.) density on wild bee foraging behaviour. Journal of Apicultural Science. 60: 49.
    Honey bees are globally regarded as important crop pollinators and are also valued for their honey production. They have been introduced on an almost worldwide scale. During recent years, however, several studies argue their possible competition with unmanaged pollinators. Here we examine the possible effects of honey bees on the foraging behaviour of wild bees on Cistus creticus flowers in Northern Greece. We gradually introduced one, five, and eight honey-bee hives per site, each containing ca. 20,000 workers. The visitation frequency and visit duration of wild bees before and after the beehive introductions were measured by flower observation. While the visitation frequencies of wild bees were unaffected, the average time wild bees spent on C. creticus increased with the introduction of the honey-bee hives. Although competition between honey bees and wild bees is often expected, we did not find any clear evidence for significant effects even in honey-bee densities much higher than the European-wide average of 3.1 colonies/km2.

Lindström, S. A. M., et al. (2016). "Experimental evidence that honeybees depress wild insect densities in a flowering crop." Proceedings of the Royal Society B: Biological Sciences 283(1843).
    While addition of managed honeybees (Apis mellifera) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (Brassica napus L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences).

Magrach, A., et al. (2017). "Honeybee spillover reshuffles pollinator diets and affects plant reproductive success." Nature Ecology & Evolution 1(9): 1299-1307.
    During the past decades, managed honeybee stocks have increased globally. Managed honeybees are particularly used within mass-flowering crops and often spill over to adjacent natural habitats after crop blooming. Here, we uniquely show the simultaneous impact that honeybee spillover has on wild plant and animal communities in flower-rich woodlands via changes in plant–pollinator network structure that translate into a direct negative effect on the reproductive success of a dominant wild plant. Honeybee spillover leads to a re-assembly of plant–pollinator interactions through increased competition with other pollinator species. Moreover, honeybee preference for the most abundant plant species reduces its seed set, driven by high honeybee visitation rates that prevent pollen tube growth. Our study therefore calls for an adequate understanding of the trade-offs between providing pollination services to crops and the effects that managed pollinators might have on wild plants and pollinators.

Mallinger, R. E., et al. (2017). "Do managed bees have negative effects on wild bees?: A systematic review of the literature." PLoS ONE 12(12): e0189268.
    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.

Müller, H. T. (2016). Interaction between Bombus terrestris and honeybees in red clover fields reduces abundance of other bumblebees and red clover yield Oslo, Norwegian University of Life Sciences M.Sc.
    Pollinator dependent crops have increased by 300%  the last 50 years. At the same time many pollinator species are declining, including honeybees and bumblebees. Red clover is one of the crops dependent on bees for seed set. It is the single most important leguminous crop for milk and meat production in Norway, but over the last years crops have declined, and insufficient pollination is a likely hypothesis to explain this. Long tongued bumblebees are the most efficient pollinators of this crop, and are simultaneously the bumblebee species declining the most. To improve yields, honeybees and another bumblebee, B. terrestris, is added to fields. Evidence on how this affects the other bumblebee species, especially long tongued species, and yield is conflicting. However, honeybees are considered poorer pollinators of red clover than bumblebees, and B. terrestris is a known nectar robber. The aim of this study was to identify whether competition occurs between honeybees, B. terrestris and other bumblebee species in red clover fields, and how these interactions may affect red clover yield.  To that objective the composition of pollinator communities in 40 red clover fields over two years were examined, and estimates for red clover yield were obtained. B. terrestris abundance was  manipulated in five fields. The results suggest that B. terrestris act as nectar robbers, facilitating honeybees and other short tongued bumblebees acting as secondary robbers. Honeybees negatively affects abundance of both long and short tongued bumblebees, indicating that competition occurs. Interaction between increased abundance of honeybees and B. terrestris seems to reduces long tongued bumblebee abundance and red clover yield.

Nielsen, A., et al. (2017). "Effects of competition and climate on a crop pollinator community." Agriculture, Ecosystems & Environment 246: 253-260.
    Plant-pollinator interactions are ubiquitous in nature where both wild and domesticated pollinators interact with wild plant communities and entomophilous crops. Honeybees are important pollinators in many crop systems, but recent declines in honeybee stocks in Europe and the US have caused concern about the sustainability of crop systems solely depending on honeybees. In addition, several studies have shown that honeybees might negatively affect native pollinator populations, bumblebees in particular. Here we have studied flower visitation to two raspberry farms and surrounding wildflower communities in SE Norway. Bumblebees were excluded from the raspberry field by means of exploitative competition from honeybees ( >97% of flower visits in the raspberry fields were conducted by honeybees). More than 55% of the visits recorded in wild plant communities surrounding the farms were conducted by bumblebees, showing that bumblebees were present in the system. Pollinator taxa were affected differently by temperature; honeybee visits showed a unimodal relationship with maximum flower visitation activity at a temperature of 24.1°C, while flower visits by bumblebees showed a positive, linear relationship with temperature. The effect of temperature was much weaker for bumblebees than for honeybees (∼2.2% of the variation was explained by temperature, compared to ∼46% for honeybees). Farming practice affected flower visitation, as flowers within growing tunnels received fewer visits. However, the number of flower visits, also within the growing tunnels, was far above what other studies have shown to be sufficient for optimal pollination in raspberry. We conclude that the raspberry fields were sufficiently pollinated by honeybees but that the system should be considered vulnerable as it is solely dependent on this particular pollinator species. The honeybees were sensitive to ambient temperature suggesting that they might suffer more from future climate change than bumblebees.

Thomson, D. M. (2016). "Local bumble bee decline linked to recovery of honey bees, drought effects on floral resources." Ecology Letters 19(10): 1247-1255.
    Time series of abundances are critical for understanding how abiotic factors and species interactions affect population dynamics, but are rarely linked with experiments and also scarce for bee pollinators. This gap is important given concerns about declines in some bee species. I monitored honey bee (Apis mellifera) and bumble bee (Bombus spp.) foragers in coastal California from 1999, when feral A. mellifera populations were low due to Varroa destructor, until 2014. Apis mellifera increased substantially, except between 2006 and 2011, coinciding with declines in managed populations. Increases in A. mellifera strongly correlated with declines in Bombus and reduced diet overlap between them, suggesting resource competition consistent with past experimental results. Lower Bombus numbers also correlated with diminished floral resources. Declines in floral abundances were associated with drought and reduced spring rainfall. These results illustrate how competition with an introduced species may interact with climate to drive local decline of native pollinators.

Torné-Noguera, A., et al. (2016). "Collateral effects of beekeeping: Impacts on pollen-nectar resources and wild bee communities." Basic and Applied Ecology 17(3): 199-209.
    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/km2) 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.

Wojcik, V. A., et al. (2018). "Floral resource competition between honey bees and wild bees: Is there clear evidence and can we guide management and conservation?" Environ Entomol: nvy077-nvy077.
    Supporting managed honey bees by pasturing in natural landscapes has come under review due to concerns that honey bees could negatively impact the survival of wild bees through competition for floral resources. Critique and assessment of the existing body of published literature against our criteria focussing on studies that can support best management resulted in 19 experimental papers. Indirect measures of competition examining foraging patterns and behavior yielded equivocal results. Direct measures of reproduction and growth were investigated in only seven studies, with six indicating negative impacts to wild bees from the presence of managed honey bees. Three of these studies examined fitness impacts to BombusLatreille and all three indicated reduced growth or reduced reproductive output. Because there is a severe lack of literature, yet potential that honey bee presence could negatively impact wild bees, exemplified with bumble bee studies, we advocate for further research into the fitness impacts of competition between managed and wild pollinators. Conservative approaches should be taken with respect to pasturing honey bees on natural lands with sensitive bumble bee populations. Correspondingly, forage opportunities for honey bees in managed, agricultural landscapes, should be increased in an effort to reduce potential pressure and infringement on wild bee populations in natural areas.

________________________________
From: Pollinator <pollinator-bounces+sam_droege=usgs.gov at lists.sonic.net> on behalf of Jennifer Geib <geibjc at appstate.edu>
Sent: Monday, January 6, 2020 10:15 PM
To: pollinator at lists.sonic.net <pollinator at lists.sonic.net>
Subject: [EXTERNAL] [Pollinator] Favorite articles/readings - pollination biology

Hello all,

Hi all,

I am very excited to be teaching an undergraduate senior-level seminar course on Pollination Biology this spring. I have a lot of ideas about what topics/readings I plan to include. However, I thought it would be fun to poll people about their favorite pollination-themed journal articles and other readings. i.e. If you were teaching such a class, what is the one (or what are the few) reading/s you feel are absolutely the most essential/interesting/poignant? It will be fun to see how everyone answers this question! Please send these to me directly (geibjc at appstate.edu<mailto:geibjc at appstate.edu>) so as not to clog up everyone's inboxes. If anyone would like me to share the compiled list, I would be happy to do so.

Thanks!
Jenni

************************
Jennifer Geib
Associate Professor, Biology
Program Director, Biology Secondary Education
Appalachian State University
(828) 262-2174

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sonic.net/pipermail/pollinator/attachments/20200110/b604c819/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: GCT Responses to Honeybee Permitting BMPs 2019 Region 4.pdf
Type: application/pdf
Size: 273971 bytes
Desc: GCT Responses to Honeybee Permitting BMPs 2019 Region 4.pdf
URL: <http://lists.sonic.net/pipermail/pollinator/attachments/20200110/b604c819/attachment-0002.pdf>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Flyer_HoneybeesAreCallingYou_2019_10_17.pdf
Type: application/pdf
Size: 471284 bytes
Desc: Flyer_HoneybeesAreCallingYou_2019_10_17.pdf
URL: <http://lists.sonic.net/pipermail/pollinator/attachments/20200110/b604c819/attachment-0003.pdf>