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A Closer LOOK: Pollih8f~r-D ~ e • -- -

Collison, Clarence. Bee Culture. Sep 2024.

Honey bees are the mos t important pollinato

. . ;Y ~ '- k
rs of agncultural. and hort
.
icultural vol..u
.
e.. <S> -- .
be.e s ecovt.oKt<cq-
t~ •
s. Mos t fruit , sma ll seed and many vegetable crops requir~ poll1~at1on to
~ crop ter
. prod uce eco nom ic yield s. The value of the honey bee as a pollinator ,s far grea
,6l'<'e ~C>- ~i'
uce
0
"~L !.ha n its valu e as a hone y producer . Not all crops need pollination. Some can prod
t~ h
flo~er. Some flowers are self-pollinated, whic
~;. .,J .:t, fru it with out fertilization of the same flow er or
from the anther to the stigma of the
,.__,_ ~ means that pollen is transferred h. db °
• d r
~ ~e. 8
f•~ -ue "' flowers on the same plant variety. Although this transfer can be ac ,eve Y w,n
. Of all the insects, hive bees are the "! c ;!: \oQ
rain, inse ct pollinators are the mos t effective «:~ ,, -
ed in sufficient num bers and plac ed in l"t&
mos t practical for crop pollination, can be rear ~~
~ffective ~oll~nation. It ha~ been fou nd
orchards where~er and whenever required for
increase m 1elds an kwe__l:Kes. ,,,_.,...e ~
~t -
. that the use of hive bees res ult~ ~- rrlc:l_lllifold e; u~t --
lity of prod uce (Abrol, 2012 ). ~~~ -\-e 'cie.i A..r I.()
~n the qua

acc:.ounting K>r~35% of the .gil ol:i rl:l- ~7,;c.. {

{.
lN!.Qre th.m i 70% mll:ie:teadin_g g{Q baltood ~TOB
...S..

polhnators - managed honey bees and wild

bees - are currently decflmng m man y
~ ct7
crops it is unk now n whe ther man age d ;3_
t'«.. ...,. t~
regions worldwide. For the vast majority of f
pollinators. and how the poll inat ion if ~
hon.e:t bees or wild bee_s are the mo~t efficient ~l.~~
(Holzschuh et al., 201 2).
service provided by wild bees can be ensured
~~
ding hab itat des truc tion , pe stic ide s,- ,~
Pollinators are faci ng a num ber of threats inclu ~
s, para sites , dise ase s and loss of gen etic diversity {Paudel et al., 201 5). Th e~ c~
mite
a trend tow ards a futu re poll inat or ~Jc :u,- J..o
number of honey bees '.s decreasing sh~wing
short~ge (Ba~er and W1~g, 2010). Many mt~
racting fact ors are beli eve d to be ~'t_~e,..
5
/wild bee pop ulat ions in the Unit ed Stat es -H ~
associated with the decline of honey bee
and Europe. In all likelihoo d, no one fact or on its own can acc qun t for all loss es ove r C:.:.ie,i~f7t
1
e
tlc. .er-.. LA.a
ors can occu r simu ltan eou sly and som e influ enc e on~
Tu~~~
a give n time peri od. Man y fact
ecent dec line s in hon ey bee
another_ (vanEng~lsdorp_and Meixner, 201 O).R ·
ct-pollinated crop s rais e con cern s ab t
populations and 1ncreas1ng demand for inse
path oge ns may inte ract to hav e stro ~~
poll in~t or shortages. Pesticide exposure and
nies Such find ings are of great con cern
negative effe cts on managed honey bee colo
y
•
•

I ·
high levels of pes ticid es foun d I·n hone y b ee co onIe s
-given •the large. numbers and
•

. •
. . vant comb,·nat,·o ns an d Ioa d s of
Thus, 1t 1s crucial to determine how field-rele
. . cted from be h· • .
pest1c1des affe ct bee health. Pollen was colle e 1ves 1n sev en maJor
1'-
\. _s~~C>...V'Ci\ :t:lG.~q,1:orS ~~ ~ re_
~~
0 , .1 •
~ t - P.occ;> i....-\ 0.X~
U . L• . ) \O\A.t v ~-.
of -~ ,~{ ~vt.~
' ~ °" \ ,.'1
~
u
l;
'-- s ,·e s~ ~~ '- LL r
-W ...
~e . ., .L! r , I '-e,.. ~
(Ue.t -e. LS PV'~ ok;,~ 0 ~
' ~~({~ ~ r - , f'e .sr -~ I

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'i ~ .. (9es. -fcc~ ~ ~<2LA- \..<:_e( 1q.~'-'

Ce os&c .-t- °'-- be.a SL-\.S ~"h~lo tl~tJ
f 'k, ~ -
exposed to when rented or 6&.& ~ ~
C '("o ,- - - -

crops to determ ine 1) what types of pesticides bees are

affect bees'
pollination of various crops and 2) how field-relevant pesticide blends
ent pollen
susceptibility to the gut parasite Nosema cerariae. Our samples repres
te fora gers ~~ -~~
collected by foragers for use by the colony, and do not necessarily indica
melon, co[e d;~
roles as pollinators. In blueberry, cranberry, cucumber, pumpkin and wate~
during our J ~ U-0A-- ~
bees ~ollected pollen almost exclusively from weeds and wil~flowers
ed to ~tr~ e.f~
sampltng. Thus, more attention must be paid to how honey bees are expos 1

~t . ~ ~.,
pest!c!des outside of the field in which they are placed. Thirty-fiv~ differe 1
1de loacfs. ~ i ° " '
pest1c1des were detected in the sampled pollen, and they found high fung1c
~~
l'ks e. The insecticides·eSfe"nvalerate and p):iosmet were at a concentration higher than ~ k;.c//
filAQi~i~e are typically
~e Wh eir medi~n lethal dose in at least one pollen sample. While
osema f ~ - t -
lv~t - ¢ ~een ~s f~1rly safe for ~ey bees, they found an~crease~ ~robab1hty o. f;J~ ~~
resul~s
~.! :{- 1~fec~1on in bees that consumed pollen with a fiigher fun~1~1de load. Their
1des and other chem1ca ~ - ;
""!'.U ,§f1g hhgh t a need for research on sublethal effects of fung1c
'° that bees placed in an agricultural setting are exposed to {Pettis et al.,
2013). ct- ~~
.
~ceu.~
~ 2ot~ ff ½•- ,
s~~ . .
& Nutrition plays an important role to maintain the health of honey bee colonies ~( ~e&. :
~~ t~
difficulty accessing 7~
l ~ {Brodschneider and Crailsheim, 201 0). ·If tioney bees have
weake~ed. \ ::.:::.+~s, i
j':;~ ~ sufficient pollen sources for all their essential arhino acids they_ may be
To ma1 nt~~ ~k~~ _ 1
and make them be more vulnerable to various ttatho~os and diseases.
""'-.s. ~ 1
If°~ 15
~Z -J health, foraging bees need a variety of sources of natural nectar and
pollen to
schneider
~½ , prevent nutritional deficiency and to strengthen immune defenses {Brod
; {Paudel et al.,
-n .. and Crailsheim, 201 O; Alaux et al., 201 O; Pedersen and Omholt; 1993)
f-~~~ ... -II __../
\IM.~ ti-t.'
b e _ ~ 201~ )-~_ ~_-0 ..,& -~~I ~ -0 b
~+ ~- .., ~n e. l-..,,.,,..-f;...!t/. -l'L.c.. 1-uLLfn'.e..-.ls is'"-'-':: :J~· I s, =
Pd,& ~T he western or European honey bee
{Apis mellifero} the primary managed
for food production is ~.::: :,~ <;,::;,,ec)_
~ : pollinator in U.S. agricultural systems, and its importance
species in ~ cl~~
~~~S Wid ely recognized. However, the role of A. mellifera as an introduced
c ~ il.,J- ,
~ I i ~ natural areas is potentially more complicated. The. impact of A. mellifera on native-/-l ,... ~ 1

xt, as can the relative ~ Jh , ,

r~h i<.> insect pollinators can depend on broad community conte
Ok.. ka;n~

and nonnative plant spec iet~. ; · '

c~""( ~c.~ effectiveness of A. mellifera in pollination of both native
:- ::ro uts ide o~ agricultural syste~s. Apis melli~era is a hi~h ~ener
alist ~nd ab e to ~ "'!~
n. It is f<>/ .&:~ ~
·c~ interact with hundreds of native plant species following its naturalizatio
alized plant specie ,
:Wa t~ ,S unlikely to wholly replace native pollinators as visitors of speci
ra's per-visit efficiency, A- ~ .n
/'k, 1,utfii,.,i and its behavioral characteristics tend to reduce A. mellife
7 inary results of our case study · •0--cq~r ~u"~~ l
fci~ ~r • even when its overall effectfiveness .is high. Prelim
'~b"'-'tve,(' ¼ . h . o A. mell1f era vs.
.
native bees of
.
pollin ators of native b
lS
~ '1
-C)(..,
i _
1 +
~- 1_r exploring t e importance
'~~ -I- u. u '40-lA.- MIC-
~ OCcJ.l1'1..e1 'Lt~ IMtc<L l

.,.,\,,~ ~,:- -rtd ;

Tl'

~ eve.- "tt> i-,.-...1"!<'" i¼ cL,-x c,tJ·

w~.t..':!~ o r--s~ s is b':j_ 1,,6
~ bee .~~ t•V'f:[ ':s z~ ' ~ ~
tie~ €,.~fu ~ I "lr~k .._~'t f,~°'- ~
c,o~ . ve 4 ~ ~v- e
.• 3
~:5
~-r 'k.t -r- Q.
~e, \<2 >
~e. .ae d~ ,~
bees .~if eif' CJ\
a is less important than native Hylaeus
pla nts in Hawaii indicate tha t A. mellifer -J- re,k~
l native plan t spe cies . In light of current global declines in co--'
as a flow er visi tor of foca
of a diversity of pollinators and pollina
tor ..._.._,-ftve bf2"N
A. mellifera populations, maintenance ..fc:,\.,! J 1oc..
in natural areas (Asian et al., 2016). d.-..
le) '
"'3~ vie.€ cA
hab itat are critical conservation needs ~ V\.'-,.

~ 4 div -or ~,~ #

definition provide high_ ~ag nitu de and
~ c.. - -tC,...e
Sust~_inable agricultural landscapes by
. However, few leuw(s-<?a('e
stabrhty of ecosystem services, biodiversity and crop productrvIty
the stability of ecosystem services. aJs
c c~ e-
e con side red land sca pe effe cts on 7
fe(c.c • stu die s hav a~ ~e :~' :_ "'
ally diverse natu ral an? sem i-na tura l a~e
-\o .•We tes ted wheth~r isolation from flor on Cc>f'l'ek~o,.,?
s the( spa t1al and ltem por al stab ility of flower-visito~ nch~ess and p~lhnat1
_ re( ~': j red uce -e::-1
p ,~ ds. We isyn th~ ized data from 29 studies with cont_r~stm~ _ <:3'°~(/-'v-
: 4o /cc ~½ , s~rv,ces m cro er-vrsrtor nchnes~,
pollinator communities. Stability of flow
sr,c -e. bro mes , cro p spe cres and
bees) and frui t set all decreased with
½v~;ri~,~
v'.sitation rate (all insects except honey t- ;¢ ~ ~
nat ura l area s. ~1 km (32 80.s ·teet) from adjacent natural areqs, (-e.a
dist anc e from
rich ness, visitation and frai t sg.t, ~
~~"
by 25, 16 and 9% for
~~ el" ' -~P -,gt ial sta bilit y dec rea sed
13% for ~~
le tem por al stab ility decreased by 39% for richness and
isolation, by 3.,➔, ~v"e ..~
~f'~ resp ecti vely , wht
visitation and fruit set also decreased with
C

j~ visi tatio n.LM ean rich nes s,

~
), respectively. In contrast, hon_e~ b~e ~
k~ 2.7 _an~ 16~ at one kilometer (3280.8 feet
cha nge with isol atio n and rep rese nted > 25% of crop v1s1ts 1n 21 ~li. .~c ,..., {~
~ v1s1tat1on drd not y ~'lcu-J.k..~s
relevant for crop productivity and sta bilit
re ~ stud ies. The refo re, wild poll inat ors are
s to preserve and restore natural areas
e'-f '--~ tf s
z
~ 35 ~ even whe n hon ey bee s are abu nda nt. Pol icie
~ r ,;;~
'rJ. d in agricultural land sca pes sho uld e,a nce leve ls and reliability of pol lina tion

~ 1o ~.,.. services (Garibaldi et al., 2011 ).

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