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Maybe one of these:<br>
<br>
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.<br>
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.<br>
<br>
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.<br>
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.<br>
<br>
Geldmann, J. and J. P. González-Varo (2018). "Conserving honey bees
does not help wildlife." Science 359(6374): 392-393.<br>
<br>
Goras, G., et al. (2016). Impact of honeybee (Apis mellifera L.)
density on wild bee foraging behaviour. Journal of Apicultural
Science. 60: 49.<br>
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.<br>
<br>
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).<br>
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).<br>
<br>
Magrach, A., et al. (2017). "Honeybee spillover reshuffles
pollinator diets and affects plant reproductive success." Nature
Ecology & Evolution 1(9): 1299-1307.<br>
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.<br>
<br>
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.<br>
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.<br>
<br>
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.<br>
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. <br>
<br>
Nielsen, A., et al. (2017). "Effects of competition and climate on a
crop pollinator community." Agriculture, Ecosystems &
Environment 246: 253-260.<br>
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.<br>
<br>
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.<br>
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.<br>
<br>
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.<br>
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.<br>
<br>
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.<br>
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.<br>
<br>
<br>
<div class="moz-cite-prefix">On 7/9/2018 9:41 PM, Barbara Passero
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:C31AF4AD37E84EFABB5AABB7DF7C9722@BarbaraWin7">
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<div>Hi David and others,</div>
<div> </div>
<div>I’m looking for an article I read on this listserv that
described how honey bees are outcompeting domestic bumble
bees. </div>
<div> </div>
<div>It seems to me that development of open space is speeding
up just as it becomes even more critical to save the land. </div>
<div> </div>
<div>I wonder whether the public would rally if they knew that
their “all you can eat buffet” would eventually consist of
all the rice you could eat.</div>
<div> </div>
<div>Thanks, Barbara</div>
<div style="FONT-SIZE: 12pt; FONT-FAMILY: 'Verdana'; COLOR:
#000000">Barbara Passero, Director<br>
MEADOWSCAPING for Biodiversity<br>
174 Moody St. #244<br>
Waltham, MA 02453<br>
Office: 781-209-0052 Cell: 617-999-9546<br>
<a class="moz-txt-link-abbreviated" href="mailto:bpassero@meadowmaking.org">bpassero@meadowmaking.org</a><br>
<a class="moz-txt-link-freetext" href="http://www.meadowmaking.org">http://www.meadowmaking.org</a><br>
</div>
<div> </div>
<div> </div>
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<div style="FONT: 10pt tahoma">
<div style="font-color: black"><b>From:</b> <a
title="dwinouye@gmail.com"
href="mailto:dwinouye@gmail.com"
moz-do-not-send="true">David Inouye</a> </div>
<div><b>Sent:</b> Tuesday, July 03, 2018 9:21 AM</div>
<div><b>To:</b> <a title="pollinator@coevolution.org"
href="mailto:pollinator@coevolution.org"
moz-do-not-send="true">pollinator@coevolution.org</a>
</div>
<div><b>Subject:</b> [Pollinator] Honeybees finding it
harder to eat at US bee hot spot</div>
</div>
</div>
</div>
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#000000 4px solid; BORDER-RIGHT-COLOR: #000000">
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<h2 class="mc-toc-title" style="FONT-SIZE: 22px;
FONT-FAMILY: 'Times New Roman', times, baskerville,
georgia, serif; FONT-WEIGHT: bold; COLOR: #202020;
PADDING-BOTTOM: 0px; FONT-STYLE: normal; TEXT-ALIGN:
left; PADDING-TOP: 0px; PADDING-LEFT: 0px; MARGIN: 0px;
DISPLAY: block; LETTER-SPACING: normal; LINE-HEIGHT:
normal !important; PADDING-RIGHT: 0px"><a
style="TEXT-DECORATION: none !important; FONT-WEIGHT:
normal; COLOR: #000000 !important;
-MS-TEXT-SIZE-ADJUST: 100%; mso-line-height-rule:
exactly; -webkit-text-size-adjust: 100%"
href="https://ehn.us16.list-manage.com/track/click?u=73be43273a8ebb733ab2696c7&id=66d66dd6bf&e=df8f3d14a2"
moz-do-not-send="true"><span style="FONT-FAMILY: times
new roman,times,baskerville,georgia,serif">Honeybees
finding it harder to eat at US bee hot spot</span></a></h2>
<a style="TEXT-DECORATION: none !important; WIDTH: 100%;
FONT-WEIGHT: normal; COLOR: #2baadf;
-MS-TEXT-SIZE-ADJUST: 100%; DISPLAY: block;
mso-line-height-rule: exactly; -webkit-text-size-adjust:
100%"
href="https://ehn.us16.list-manage.com/track/click?u=73be43273a8ebb733ab2696c7&id=c47eceac28&e=df8f3d14a2"
moz-do-not-send="true">www.cbc.ca</a>
<div style="WIDTH: 100%; DISPLAY: block">Bees are having a
much harder time finding food in the Northern Great
Plains of the Dakotas, known as America's last honeybee
refuge, according t...</div>
<p> </p>
<p><a class="moz-txt-link-freetext"
href="https://www.cbc.ca/news/technology/honeybees-harder-to-eat-1.4731277"
moz-do-not-send="true">https://www.cbc.ca/news/technology/honeybees-harder-to-eat-1.4731277</a><br>
<br>
</p>
<pre class="moz-signature" cols="72">--
Dr. David W. Inouye
Professor Emeritus
Department of Biology
University of Maryland
College Park, MD 20742-4415
<a class="moz-txt-link-abbreviated" href="mailto:inouye@umd.edu" moz-do-not-send="true">inouye@umd.edu</a>
Principal Investigator
Rocky Mountain Biological Laboratory
PO Box 519
Crested Butte, CO 81224</pre>
<p>
</p>
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</div>
</div>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Dr. David W. Inouye
Professor Emeritus
Department of Biology
University of Maryland
Principal Investigator
Rocky Mountain Biological Laboratory</pre>
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