Pesticides and Honey Bee Death and Decline

stress, and one of those stresses ispesticides (Spivak et al. 2011;USHR 2008; Quarles 2008a). Oneobservation that seems to implicatepesticides is that organic beekeep-ers do not seem to have CCD(Schacker 2008).

By William Quarles

Alarge number of overwinter-ing honey bees are dying inthe U.S. For the last five

years, winter losses of managedhoney bee colonies have beenaround 30% each year (vanEngelsdorp et al. 2012). Over-wintering honey bees are beingkilled by pathogens, pests, poornutrition, and pesticides. Honey beeproblems are part of the overall pol-linator decline in the U.S. (Spivak etal. 2011; NAS 2007).Managed honey bees are trucked

from state to state and forage overlarge areas. Most of the crops theyencounter have been treated withpesticides, and chemical analysis ofoverwintering honey bee hivesshows extensive pesticide contami-nation (Mullin et al. 2010).Pesticides are accumulating in

hives, and bees are also being killedwhile foraging in fields (Krupke etal. 2012). Part of the problem isexposure to systemic insecticidescalled neonicotinoids. Insecticidesare normally applied in ways tomitigate their impact on bees.Mitigation strategies are not possi-ble with systemics because they arealways present in the plant. Over59 million ha (146 million acres) ofcrops in the U.S. have been treatedwith systemics. This representsabout 45% of the total cropland,and acreage is increasing each year(Mullin et al. 2010; Stokstad 2012;Spivak et al. 2011).Pesticides can impact bee popula-

tions through direct mortality andthrough sublethal effects on behav-ior, such as impaired memory,learning and foraging. Impaired for-aging can lead to poor nutrition,and pesticides may directly impact

bee immune systems, making themmore susceptible to disease. Inaddition, sublethal pesticides inter-fere with brood development andshorten lifespans of adults (Henryet al. 2012; Pettis et al. 2012; Wu etal. 2012; Desneux et al. 2007).Pesticides may also contribute to

Colony Collapse Disorder (CCD).This phenomenon was firstobserved in the U.S. in 2006. Beesdisappear from the hive, leavingfood, brood, and even a queen(USHR 2007; Quarles 2008a).Despite intensive research, an exactcause of CCD has not been identi-fied. There may be a number ofcauses working synergistically. Butit has been established that over-wintering bee colonies are under

In This Issue

Honey Bees 1Backyard Chickens 9ESA Report 10EcoWise News 11Calendar 12

Volume XXXIII, Number 1/2, January/February 2011

Pesticides and Honey BeeDeath and Decline

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A honey bee, Apis mellifera, is headed toward an almond blossom. Massivelosses of these managed honey bees are occurring each year, and pesticidepoisoning is part of the problem.

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2 Box 7414, Berkeley, CA 94707IPM Practitioner, XXXIII(1/2) January/February 2011

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Are Pesticides found inBee Hives?

Bees can come into contact withpesticides when foraging or whenthe hive is treated with pesticides tokill mites. Foragers can collect con-taminated pollen and nectar andbring it back to the hive. Some ofthe nectar and pollen is mixedtogether with enzymes to form beebread. In the hive bees evaporatewater from nectar to producehoney. Any pesticide in the nectaris concentrated at least 4x in thehoney, which is stored for later use.So bees can be exposed both in thefield and in the hive (Bonmatin etal. 2005; Kievits 2007).Bee exposure to pesticides is

widespread. Mullin et al. (2010)checked a large number of commer-cial bee hives for pesticides. Hivesfrom 23 states including Florida,California, Pennsylvania and migra-tory bees from East Coast colonies

were analyzed. Wax, pollen, andbees were highly contaminated withpesticides. There were 121 differentpesticides and metabolites in 887wax, bee, and pollen samples, aver-aging about 6 pesticides per sam-ple.This diverse contamination opens

the question of synergism. Mixturesof pesticides are known to be moretoxic to bees than individual prod-ucts. Some fungicides, for instance,are known to increase the toxiceffects of insecticides (Johansen1977; Atkins 1992; USHR 2008;Pilling and Jepson 1993; Schmucket al. 2003; Isawa et al. 2004).The 350 pollen samples contained

about 98 different pesticides andmetabolites in concentrations up to214 ppm. Each pollen sample aver-aged about 7 different pesticides,up to a maximum of 31.Pollen was contaminated from

miticides and fungicides applied inthe hive, and insecticides, herbi-

The IPM Practitioner is published six timesper year by the Bio-Integral ResourceCenter (BIRC), a non-profit corporationundertaking research and education in inte-grated pest management.Managing Editor William QuarlesContributing Editors Sheila Daar

Tanya DrlikLaurie Swiadon

Editor-at-Large Joel GrossmanBusiness Manager Jennifer BatesArtist Diane Kuhn

For media kits or other advertising informa-tion, contact Bill Quarles at 510/524-2567,[email protected].

Advisory BoardGeorge Bird, Michigan State Univ.; SterlingBunnell, M.D., Berkeley, CA ; Momei Chen,Jepson Herbarium, Univ. Calif., Berkeley;Sharon Collman, Coop Extn., Wash. StateUniv.; Sheila Daar, Daar & Associates,Berkeley, CA; Walter Ebeling, UCLA, Emer.;Steve Frantz, Global Environmental Options,Longmeadow, MA; Linda Gilkeson, CanadianMinistry of Envir., Victoria, BC; JosephHancock, Univ. Calif, Berkeley; WilliamOlkowski, Birc Founder; George Poinar,Oregon State University, Corvallis, OR;Ramesh Chandra Saxena, ICIPE, Nairobi,Kenya; Ruth Troetschler, PTF Press, LosAltos, CA; J.C. van Lenteren, AgriculturalUniversity Wageningen, The Netherlands.ManuscriptsThe IPMP welcomes accounts of IPM for anypest situation. Write for details on format formanuscripts or email us, [email protected].

CitationsThe material here is protected by copyright,and may not be reproduced in any form,either written, electronic or otherwise withoutwritten permission from BIRC. ContactWilliam Quarles at 510/524-2567 for properpublication credits and acknowledgement.

Subscriptions/MembershipsA subscription to the IPMP is one of the bene-fits of membership in BIRC. We also answerpest management questions for our membersand help them search for information.Memberships are $60/yr (institutions/libraries/businesses); $35/yr (individuals).Canadian subscribers add $15 postage. Allother foreign subscribers add $25 airmailpostage. A Dual membership, which includesa combined subscription to both the IPMPand the Common Sense Pest ControlQuarterly, costs $85/yr (institutions); $55/yr(individuals). Government purchase ordersaccepted. Donations to BIRC are tax-deductible.FEI# 94-2554036.

Change of AddressWhen writing to request a change of address,please send a copy of a recent address label.© 2012 BIRC, PO Box 7414, Berkeley, CA94707; (510) 524-2567; FAX (510) 524-1758.All rights reserved. ISSN #0738-968X

Helga Olkowski passed awaypeacefully at home on April 27, 2012from complications from a stroke.Helga was active in many environ-

mental organizations, and she wasco-founder of the FarallonesInstitute, the John Muir Institute,and others. Helga actively promotedorganic agriculture, writing forOrganic Gardening and other maga-zines. She was coauthor of severalinfluential books, including The CityPeople’s Book of Raising Food, TheIntegral Urban House and CommonSense Pest Control. She was co-founder of the Bio-Integral ResourceCenter (BIRC) and worked for yearsas an editor for BIRC, writing arti-cles for the IPM Practitioner andCommon Sense Pest ControlQuarterly.

Helga retired from BIRC in 1999,and spent many enjoyable yearstraveling with her husband, WilliamOlkowski. She suffered a strokeabout three years ago from whichshe never completely recovered. Wewill miss her.

A more complete biography can befound at her website www.who1615.com

Helga Martin Williamson Olkowski1931-2012

Co-Founder of the Bio-Integral Resource Center

3

cides, and fungicides applied in thefield. Pyrethroids were the most fre-quently detected insecticide, andwere sometimes found at levelsknown to disorient foraging bees.Fungicides were the predominantpesticide type found in pollen(Mullin et al. 2010).Contamination similar to this can

lead to delayed development of beesand can shorten life span of adultworkers. Premature death of for-agers forces nurse bees to forage,with further consequences oncolony health (Wu et al. 2011).

NeonicotinoidsAmong the pesticides found in

bee hives by Mullin et al. (2010)were neonicotinoids. These pesti-cides are analogs of the neurotoxinnicotine and have similar actions.Neonicotinoids include imidaclo-prid, clothianidin, thiamethoxamand others. They are applied asseed treatments to a number ofcrops, including corn, sunflower,cotton, and canola. Foliar sprays,soil drenches, and seed treatmentsare used. Both crop plants andornamentals are treated (Elbert etal. 2008; Stokstad 2012; Hopwoodet al. 2012).Mullin et al. (2010) found bee

pollen in hives contained imidaclo-prid at a median concentration of20 ppb and a maximum concentra-tion of 206 ppb. These levels areknown to impact the health of bees.A total of 43 pollen samples (12%)out of 350 contained neonicotinoidsor their metabolites. Mullin et al.were analyzing hives foraging onspecialty crops such as citrus,apples and others that do not useseed treatments. Where bees forageon crops such as corn, canola, orsunflowers that use neonicotinoidseed treatments, 50% of pollensamples carried by honey bees canbe contaminated with these pesti-cides (Krupke et al. 2012; Lu et al.2012; Blacquiere et al. 2012).There is no doubt that these

potent new pesticides can kill beesif bees are exposed. Just 3.7 bil-lionths of a gram of imidaclopridwill likely kill a bee (oral LD50= 3.7to 81 ng/bee). The oral LD50 ofclothianidin is 2.8 to 3.7 ng/bee,

and contact toxicity is 22-44ng/bee. For comparison, the oralLD50 of cypermethrin is 160ng/bee and for the organophos-phate dimethoate 152 ng/bee (Colinet al. 2004; Schmuck et al. 2001;Suchail et al. 2001ab; Krupke et al.2012).As we see in Table 1, clothianidin,

thiamethoxam, dinotefuran, andimidacloprid are extremely toxic tobees, acetamiprid and thiaclopridless so. We can also see that therecan be a wide range of toxicity.Effects can vary depending ongenetic variation in bees and otherfactors (Hopwood et al. 2012;Quarles 2008).

Complicating Factors inthe Field

Neonicotinoids are causing con-cern due to widespread bee expo-sure, their potency to bees, and

their persistence in the field (seeTable 1). Sublethal doses can causeimpaired learning and foraging.These effects have been measuredat very low concentrations in thelaboratory, but critics point out thatthere are mitigating effects in thefield. Bees can collect pollen fromuntreated plants, and dilute pesti-cide effects. So experiments withneonicotinoids and bees oftenbecome a numbers game. If aneffect is detected, the first criticismis that doses used were not repre-sentative of concentrations found inthe field (Stokstad 2012; Hopwoodet al. 2012).It is true that dilution from

untreated plants can occur in thefield. Nguyen et al. (2009) foundthat imidacloprid treated corn fieldsin Belgium had no effect on mortal-ity of honey bee hives found within3 km (1.8 mi) of the fields. However,only 13.2% of the corn acreagewithin foraging range had beentreated, and these treated fieldsrepresented a maximum 2.48% ofthe foraging area. So effects on beesfrom treated acreage can be dilutedin the field by access to other foodsources. But as more and moreacreage is planted with systemics,then bees will have problems find-ing untreated plants (Hopwood etal. 2012).Experiments have been conducted

where hives are placed near treatedfields and monitored for effects.Unfortunately, these colonies areoften monitored over a relativelyshort period of time. Honey beecolonies have at least two genera-tions a year. So it is not enough tomeasure the effects on one genera-tion. Chronic sublethal doses in onegeneration can reduce the number

3IPM Practitioner, XXXIII(1/2) January/February 2011 Box 7414, Berkeley, CA 94707

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Commercial hives can be heavilycontaminated with pesticides.

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of bees in the next generation (Lu etal. 2012).

Sublethal Doses in HivesKrupke et al. (2012) found sick

hives had pollen concentrations upto 10.7 ppb clothianidin or 20.4ppb of thiamethoxam. Pollen is fedto larvae by nurse bees. A nursebee will consume 65 mg of pollen in10 days. If the pollen contains 20ppb clothianidin, 65 mg will contain1.3 ng, about 50% of the LD50 of2.8 ng/bee. Sublethal doses of 1.3ng are high enough to disorient for-agers and cause field losses of bees(Henry et al. 2012).Sublethal concentrations of neon-

icotinoids and other pesticides inbrood comb can delay developmentof adult bees. Delayed developmentcan make the bees more susceptibleto mites. Pesticides in the broodcomb also shorten life span of adultbees (Wu et al. 2011).Bee colonies have even been

killed by feeding them neonicoti-noids at chronic sublethal concen-trations of 20 ppb, which is close towhat they could encounter in the

field. Lethal effects were not seenfor months (Lu et al. 2012).

Can Field Concentrationsof Neonicotinoids Kill

Bees?Neonicotinoids can kill bees for-

aging in fields. Most of the 35.7 mil-lion ha (88.2 million acres) of cornin the U.S. are treated. Applicationrates are 0.25 to 1.25 mg/kernel,and the pesticide on one seed isenough to kill 80,000 bees.Fortunately, most of the pesticide isburied with the seed (Hopwood etal. 2012; Krupke et al. 2012).But flying bees can be directly

exposed to aerially dispersed seedcoatings and talc from plantingmachines. Talc can contain 3,400to 15,043 ppb clothianidin, which ismany times the lethal dose for abee. Exposures of this kind have ledto honey bee deaths in the field.Mortality increases with humidity(Krupke et al. 2012; Marzaro et al.2011; Tapparo et al. 2012; Girolamiet al. 2012).In May of 2008, about 50% of

honey bees in the German state of

Baden-Wurttemberg were killed.The problem was traced to theapplication of the systemic pesti-cides clothianidin and imidaclopridto seeds. According to the manufac-turer, farmers applied these pesti-cides without using the adhesivesrecommended to keep the pesticideslocalized to seeds. Germany bannedthe use of these pesticides for seedtreatment after this incident (ENS2008; EPA 2008). Bee deaths dur-ing planting season have been seenin other European countries(Mazaro et al. 2011).Even if adhesives have been prop-

erly applied, bees can still be killedby careless operation of plantingmachines. Krupke et al. (2012)investigated the cause of dead beesin apiaries in Indiana. They foundthat dead bees and pollen fromtheir hives contained the neonicoti-noids thiamethoxam and clothiani-din. Some of the pollen sampleshad clothianidin levels higher thanthe LD50. Returning foragers fromhives near fields had pollen concen-trations up to 88 ppb of clothiani-din.Aerial seed waste also contami-

nates soil, surface water, and wildplants found near field margins.Some of these, such as dandelions,are attractive to bees. Concentra-tions of 6 ppb clothianidin werefound in soil after treated seedswere planted. Dandelion plantsnear corn fields had residues of upto 9.4 ppb. The neonicotinoids arepersistent, and some have soil halflives of more than a year. Thismeans that material from one yearcan appear in the next year’s plant-ing. Soil contamination can also putsoil nesting bees at risk (Hopwoodet al. 2012).According to the California EPA,

where imidacloprid is being used,models suggest expected concentra-tions in surface water of 17 ppb,and 2 ppb is expected in groundwa-ter. Residues on plants near a cropsite can be 14-54 ppb (Fossen2006).Some of these problems can be

mitigated by filtering air from plant-ing machines to prevent dispersal ofcontaminated talc and seed coat-ings (Mazaro et al. 2011). Other

Honey bees can be killed by acute exposure to aerially dispersed seedcoatings containing neonicotinoids. Chronic exposure can cause for-agers to lose their way home.

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Updateresearchers question the need forseed treatments in corn, citingeffective IPM practices, and theproblem of insect resistance withsystemic pesticides (Maini et al.2010).

Neonicotinoids inGuttation Drops

Bees can also be exposed throughguttation water from plants. Cornexcretes droplets of water along leafmargins called guttation drops. Forabout 3 weeks after emergence,droplets from treated corn containlarge concentrations of neonicoti-noids: 47 to 83 mg/liter imidaclo-prid, 23 mg/liter clothianidin,about 12 mg/liter for thiamethoxam(Girolami et al. 2009). Therefore,the levels in guttation fluid can be254 times the LD50 for imidaclo-prid, 280 times the LD50 for clothi-anidin and 48 times the LD50 forthiamethoxam. Guttation dropletsfed to bees in the laboratory will killthem (Thompson 2010). Lethal gut-tation drops can also be producedby melon crops with neonicotinoidsoil treatments (Hoffman and Castle2012).Critics say that bee behavior

must be taken into account.Droplets may appear in the morn-ing before bees start foraging. Beesuse water to cool their hives. Hivesmay not need cooling in the morn-ing. Guttation water may not be acommon source of water, since beesneed large amounts of water andare fond of irrigation water andlarge sources (Hopwood et al. 2012;Girolami et al. 2009).

Neonicotinoids in Pollenand Nectar

Bees can also be exposed to con-taminated nectar and pollen pro-duced by treated plants. Thoughconcentration in nectar and pollenmay be low, chronic doses canaccumulate because bee metabo-lism and elimination of neonicoti-noids such as imidacloprid (IMD)are slow. Metabolism is complexand thiamethoxam is actually con-verted by metabolism into clothiani-din (Hopwood et al. 2012; Krupke etal. 2012; Suchail et al. 2001ab).

Imidacloprid (IMD) is oftenapplied as a seed treatment.Sunflower seed treatments can leadto concentrations of 13 ppb in sun-flower pollen (Laurent andRathahao 2003). Other experimentsshow 3.9 ppb in sunflower pollen, 8ppb in flowers, and 1.9 ppb in nec-tar. Rape has 4.4 to 7.6 ppb inpollen. Corn can have average con-centrations of 2.1 ppb in pollen and6.6 ppb in flowers. Some cornplants show concentrations of 18ppb in pollen (Fossen 2006;Bonmatin et al. 2005). Bees couldingest IMD in pollen, nectar, andwater. They could be exposed bycontact on flowers and leaves of

treated plants (Blacquiere et al.2012).Treated plants metabolize IMD to

toxic metabolites, and one of themis twice as toxic to bees as IMD.Chauzat et al. (2006) found IMDmetabolites in 44% of pollen sam-ples collected in France. Bayerresearchers found that about 15%of IMD in sunflower pollen hadmetabolized (Sur and Stork 2003).Neonicotinoids are also used as

foliar sprays, as soil drenches, andfor treating landscape ornamentalsas well as crop plants. Amountsused on ornamentals lead toresidues 12-16x greater than foundon crop plants (Hopwood et al.2012).Cresswell (2011) combined a

number of studies on imidaclopridinto a meta-analysis and concludedthat “trace dietary imidacloprid atfield realistic levels in nectar willhave no lethal effects, but willreduce expected performance inhoney bees by between 6 and 20%.”

Cresswell, however, included nostudies on ornamentals and tossedout studies (Suchail et al. 2001ab)showing mortality from smallchronic doses. Also excluded werestudies showing lethal field levels ofimidacloprid due to guttationdroplets and airborne seed residues(Krupke et al. 2012; Girolami et al.2009).

Can Field Concentrationsof Pesticides Lead toImpaired Foraging?

Yang et al. (2008) found that con-centrations of imidacloprid of 40-50ppb in sugar water were enough tocause impaired foraging of honeybees in the field. Nectar concentra-tions from seed treatments arelower than this, but even if nectarconcentrations are low, fairly largechronic doses can be delivered. Abee ingests 20-30 µl of nectar eachtime, and the half life of IMD isabout 4.5 hrs, making chronicaccumulation possible. Imidaclopridis also metabolized by bees intotoxic metabolites that can alsoaccumulate (Suchail et al. 2003;2004).Although nectar from seed treat-

ments do not regularly reach 40-50ppb in the field, these concentra-tions occur with some other crops.Thiamethoxam soil drenches topumpkins at label rates with halfapplied to transplants and halfapplied during flowering led to nec-tar concentrations of 54.8-90.4 ppb(Hopwood et al. 2012). Beesexposed to this concentration couldreceive the doses used by Yang etal. (2008).Cresswell (2011) estimates that a

honeybee ingests an average nectarload of 40 mg. If nectar contained50 ppb (ng/gram), then 2.0 ng oftoxin would be ingested with eachload. Faucon et al. (2005) estimatethat foraging bees have an 11.5mg/hour nutrient need from pollenand nectar. If the pollen or nectarcontained 50 ppb, about 1.8 ng oftoxin would be accumulated in 3hours.Neonicotinoids are known to

impair bee foraging efficiency in thelaboratory. An experimental chal-lenge is measuring these effects in

Soil contamination putsgroundnesting bumble bees,Bombus spp., at risk.

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a field situation. One way is toidentify treated bees with amicrochip. Henry et al. (2012)equipped 653 honey bees with a 3mg microchip. An individual adultbee weighs 80-100 mg, so thisroughly represents a weight handi-cap of about 3%. Bees were treatedwith a sublethal dose of 1.34 ng ofthiamethoxam, which is about 27%of the LD50 of 5 ng/bee. It wasadministered in a sugar solutioncontaining thiamethoxam (1.34 ngin 20 µl).

Losses Higher inUnfamiliar Terrain

Henry et al. (2012) released treat-ed bees, along with equal numbersof untreated bees up to 1 km (0.6mi) away from the hive. Hives wereequipped with microchip (RFID)

monitoring equipment. Some of thetreated foragers were released in afamiliar field of Phacelia, otherswere released in unfamiliar sur-roundings. About 10% of treatedbees released in familiar surround-ings failed to make it back to thehive. About 32% of treated beesreleased in unfamiliar surroundingsfailed to return. Most commercialhoney bee hives are trucked fromplace to place and released in anunfamiliar environment, maximizingpesticide effects on foraging.Schneider et al. (2012) found sim-

ilar results with microchip experi-ments. When bees were treatedwith 1 ng of orally ingested clothi-anidin, about 26% did not return tohive. With 2 ng, 79% did notreturn. Impairment was noticed at

1.5 ng imidacloprid or 0.5 ng clothi-anidin.Calculations by Henry et al.

(2012) showed that if 90% of acolony was exposed to nectar of atreated oilseed crop each day, andthese levels of foraging mortalityoccurred, “populations would followa marked decline during the bloom-ing period, and would hardly recov-er afterwards.”Releasing treated bees in a famil-

iar area only 70 meters (230 ft)from the hive still led to excess for-ager mortality—about 6% of themdid not return. Field impact studiesoften put hives immediately adja-cent to treated fields to assesseffects. This study shows that thismethod would tend to underesti-mate pesticide induced foragingimpairment (Henry et al. 2012).

Bumble Bees also AffectedAlthough the latest research does

not definitely establish a uniquelink between neonicotinoids andcolony collapse disorder, it doesshow that neonicotinoids can havedetrimental effects on bees at real-istic field concentrations. Bumblebees, native bees, and honey beesare all at risk (Hopwood et al. 2012;Quarles 2008b). Several studieshave shown that field concentra-tions in pollen and nectar from seedtreatments on average are in therange 0.7-10 ppb. Concentrationsas high as 88 ppb have been foundin corn pollen (Krupke et al. 2012).Sublethal doses of IMD have been

shown to affect bumble bee forag-ing. After 9 days of foraging in sun-flowers treated with IMD, about10% more bumble bees were lost inthe field compared to bumble beeforagers in untreated fields (Taséi etal. 2001).Whitehorn et al. (2012) fed 25

bumble bee colonies in the labora-tory for 14 days on pollen contain-ing 6 ppb imidacloprid and sugarwater containing 0.7 ppb.Exposures of this sort would beobtained if bees foraged mostly ontreated fields, and rarely soughtalternate food sources. Another 25colonies received food containingtwice this concentration and anoth-er 25 were fed untreated food.

Colonies were then left to forage inthe field for six weeks.After six weeks, treated colonies

weighed 8-12% less than untreatedcontrols. This amount represents acombined drop in weight of foodstores, wax, immature and adultbees. The weight drop was likelydue to pesticide induced impair-ment of food gathering efficiency.Treated colonies also had on

average about 85% fewer queens(13.72 vs 1.7), probably becausebumble bee queen production isdependent on colony size. Accordingto Whitehorn et al. “our resultssuggest that trace levels of neoni-cotinoid pesticides can have strongnegative consequence for queenproduction by bumble bee coloniesunder realistic field conditions, andthis is likely to have a substantialpopulation level impact.”

Summer Bees, Winter BeesThere are two kinds of adult

honey bees—summer bees thathave a relatively short lifetime (40days), and adult winter bees thatlive for 6 months or more. Summerbees gather food and feed the larvaethat will develop into adult winterbees. Winter bees emerge Septem-ber through November, and areresponsible for colony overwinter-ing, sometimes in very cold situa-tions (see Quarles 2008a).Most of the massive bee kills in

the U.S. are occurring during over-wintering. Large numbers of for-agers collect nectar and pollen dur-ing the summer. Foraging kills a lotof them, and colony numbers dropin the fall. A smaller colony over-winters, then queens start layingeggs in late December, and thecolony starts to expand in January(Winston 1987; Langstroth 1923;Morse 1975).Adult winter bees are old bees,

and are physiologically differentfrom summer bees. Because of theirrelatively long lifetime, winter beeshave had more time to be exposedto pesticides and pathogens. Winterbees are often more susceptible topesticides. This may be becausethey have greater fat deposits,allowing pesticides to accumulate.For instance, winter bees are 4x

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Foraging of bumble bees,Bombus spp., can be impairedby neonicotinoids.

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more sensitive to the chronic lethaleffects of imidacloprid than aresummer bees. Cold temperaturesalso make pesticides more toxic tobees (Decourtye et al. 2003;Johansen 1975; Belzunces et al.2001b).

Summer Bees Poisoned,Winter Bees Die

Most of the bee toxicity experi-ments are done either on individualbees or on hives monitored for alimited amount of time. Lu et al.(2012) chronically dosed summerbees with imidacloprid, thenstopped. Mortality was delayed forseveral months. Bees were fed imi-dacloprid in high fructose cornsyrup for about three months (13weeks), starting July 1. Very lowconcentrations were used for onemonth, then amounts likely tocause damage were fed for twomonths. High fructose corn syrupcontaining 20, 40, 200, and 400ppb imidacloprid were fed to thebees. Treatment was applied fromJuly 1 to September 30.After treatment, bees were

allowed unhindered foraging untilmid December, when overwinteringcolonies were given supplementalfood. All colonies were still alive 12weeks after the last dose was given(December 22), but hives receiving

the largest dose were showing sometoxic effects. However, 23 weeks(March 10, 2011) after the last doseof imidacloprid, 15 of 16 of thetreated hives were dead.Dead hives had no bees, but still

had food. Summer bees were fedimidacloprid, and the winter beesdied. This kind of delayed mortalitymimics some of the manifestationsof Colony Collapse Disorder. Thelowest feeding dose was 20 ppb.Earlier experiments had shown noeffect on overwintering bees whensummer bees were fed 5 ppb of imi-dacloprid in sugar syrup. Therewere four untreated control hives,and three of four survived (Fauconet al. 2005; Lu et al. 2012).Since this experiment mimics

some of the manifestations ofColony Collapse Disorder, Lu et al.(2012) hypothesize that bee keepersmay have produced CCD by feedingoverwintering bees with corn syruplaced with imidacloprid. Imidaclo-prid is used extensively on corn,and relatively high tolerances (50ppm) are permitted. However, theresearchers provide no evidencethat high fructose corn syrup iscontaminated with IMD. Furtherresearch is needed to confirm theseresults and to check field samplesof corn syrup for pesticide contami-nation.

ConclusionHoney bees receive widespread

exposure to pesticides. Large num-bers of different pesticides accumu-late in stored pollen and in waxcombs. Large numbers increase thelikelihood of synergism. Sublethalconcentrations known to affect beehealth and behavior have beenfound in many bee hives.Pesticide exposure is a likely con-

tributing factor to colony collapsedisorder. Pesticides can depress thebees’ immune system, interfere withnormal brood development, andlead to poor nutrition throughimpaired foraging. Sublethal dosescan shorten lifespan, and makebees more susceptible to mites andpathogens. Effects can be subtle, asbees poisoned in one generationmay not show effects until the nextgeneration appears.Though bees are being impacted

by a large number of pesticides,neonicotinoids are receivingincreased attention. Widespread useof seed treatments, foliar sprays,and soil drenches are exposing beesto these potent pesticides over alarge area. Careless use of plantingmachines is contaminating water,soil, and wild plants near treatedfields, and exposing bees to lethalairborne seed waste and talc.

William Quarles, Ph.D., is an IPMSpecialist, Executive Director of theBio-Integral Resource Center (BIRC),and Managing Editor of the IPMPractitioner. He can be reached byemail, [email protected].

ReferencesAtkins, E.L. 1992. Injury to honey bees by poi-

soning. In: The Hive and the Honey Bee,rev. ed., J.M. Graham, ed. Dadant andSons, Hamilton, IL. 1324 pp.

Belzunces, L.P., C. Pélissier and G.B. Lewis,eds. 2001a. Hazards of Pesticides to Bees.INRA, Paris. 308 pp.

Belzunces, L.P., R. Vandame and X. Gu. 2001b.Joint effects of pyrethroid insecticides andazole fungicides on honey bee thermoregu-lation. In: Belzunces et al., 2001a, pp. 297-298.

Blacquiere, T., G. Smagghe, C.A.M. van Gesteland V. Mommaerts. 2012. Neonicotinoids inbees: a review on concentrations, sideeffects, and risk assessment. Ecotoxicol.Feb. 18, 2012. Online, 20 pp.

Bonmatin, J.M., P.A. Marchand, R. Charvet, I.

7

Closeup of a hive killed by Colony Collapse Disorder. Note that broodis present, but all adult bees have disappeared.

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the foraging behavior of Apis mellifera. PLoSONE 7(1):e30023. 9 pp.

Spivak, M., E. Mader, M. Vaughan and N.H.Euliss, Jr. 2011. The plight of the bees.Environ. Sci. Technol. 45:34-38.

Stokstad, E. 2012. Field research on bees raisesconcern about low-dose pesticides. Science335:1555.

Suchail, S., D. Guez and L.P. Belzunces. 2001a.Toxicity of imidacloprid and its metabolitesin Apis mellifera. In: Belzunces et al.,2001a, pp. 121-126.

Suchail, S., D. Guez and L.P. Belzunces. 2001b.Discrepancy between acute and chronic tox-icity induced by imidacloprid and itsmetabolites in Apis mellifera. Environ.Toxicol. Chem. 20(11):2482-2486.

Suchail, S., G. DeSouza, R. Rahmani and L.P.Belzunces. 2004. In vivo distribution andmetabolism of 14C-imidacloprid in differentcompartments of Apis mellifera. PestManag. Sci. 60:1056-1062.

Suchail, S., L. Debrauwer and L.P. Belzunces.2003. Metabolism of imidacloprid in Apismellifera. Pest Manag. Sci. 60:291-296.

Sur, R. and A. Stork. 2003. Uptake, transloca-tion and metabolism of imidacloprid inplants. Bull. Insectol. 56(1);35-40.

Tapparo, A., D. Marton, C. Giorio et al. 2012.Assessment of the environomental exposureof honeybees to particulate matter contain-ing neonicotinoid insecticides coming fromcorn coated seeds. Environ. Sci. Technol.46:2592-2599.

Taséi, J.N., G. Ripault and E. Rivault. 2001.Effects of Gaucho® seed coating on bumble-bees visiting sunflower. In: Belzunces et al.2001a, pp. 207-212.

Thompson, H.M. 2010. Risk assessment forhoney bees and pesticides—recent develop-ments and new issues. Pest Manag. Sci.66:1157-1162.

USHR (United States House of Representatives).2007. Colony Collapse Disorder andPollinator Decline. Subcommittee onHorticulture and Organic Agriculture.March 29, 2007.http://agriculture.house.gov

USHR (United States House of Representatives).2008. Pollinator Health and Colony CollapseDisorder. Subcommittee on Horticultureand Organic Agriculture. June 26, 2008.http://agriculture.house.gov

Van Engelsdorp, D., D. Caron, J. Hayes et al.2012. A national survey of managed honeybee 2010-11 winter colony losses in theUSA: results from the Bee InformedPartnership. J. Apicultural Res. 51(1):115-124.

Whitehorn, P.R., S. O’Conner, F.L. Wackers andD. Goulson. 2012. Neonicotinoid pesticidereduces bumble bee colony growth andqueen production. Science Express March29, 2012. 3pp.

Winston, M.L. 1987. The Biology of the HoneyBee. Harvard University Press, Cambridge,MA. 281 pp.

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Yang, E.C., Y.C. Chuang, Y.L. Chen and L.H.Chang. 2008. Abnormal foraging behaviorinduced by sublethal dosage of imidaclopridin the honey bee. J. Econ. Entomol.101(6):1743-1748.

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Langstroth, L.L. 1923. On the Hive and theHoney Bee, 22nd ed., rev. C.P. Dadant, TheAmerican Bee Journal, Hamilton, IL. 438pp.

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Laurino, D., M. Porporato, A. Patetta and A.Manino. 2011. Toxicity of neonicotinoidinsecticides to honey bees: laboratory tests.Bull. Insectol. 107-113.

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Morse, R.A. 1975. Bees and Beekeeping. CornellUniversity Press, Ithaca, NY. 295 pp.

Mullin, C.A., M. Frazier, J.L. Frazier et al. 2010.High levels of miticides and agrochemicalsin North American apiaries: implications forhoney bee health. PLoS ONE 5(3):e9754. 19pp.

NAS (National Academy of Sciences). 2007.Status of Pollinators in North America.National Academy Press, Washington, DC.300 pp.

Nguyen, B.K., C. Saegerman, C. Pirard et al.2009. Does imidacloprid seed-treated maizehave an impact on honey bee mortality? J.Econ. Entomol. 102(2):616-623.

Nixon, G. 1954. The World of Bees. Hutchinson,London. 214 pp.

Pettis, J.S., D. van Engelsdorp, J. Johnson andG. Dively. 2012. Pesticide exposure inhoney bees results in increased levels of thegut pathogen Nosema. Naturwissenschaften99:153-158.

Pilling, E.D. and P.C. Jepson. 1993. Synergismbetween EBI fungicides and a pyrethroidinsecticide in the honey bee (Apis mellifera).Pesticide Sci. 39:293-297.

Quarles, W. 2008a. Pesticides and honey beecolony collapse disorder. IPM Practitioner30(9/10):1-10.

Quarles, W. 2008b. Protecting native bees andother pollinators. Common Sense PestControl Quarterly 24(1-4):4-14.

Schacker, M. 2008. A Spring without Bees: HowColony Collapse Disorder Has Endangeredour Food Supply. The Lyons Press,Guilford, CT. 292 pp.

Schmuck, R., R. Schoning, A. Stork and O.Schramel. 2001. Risk posed to honeybees(Apis mellifera: Hymenoptera) by an imida-cloprid seed dressing of sunflowers. PestManag. Sci. 57:225-238.

Schmuck, R., T. Stadler and H.W. Schmidt.2003. Field relevance of a synergistic effectobserved in the laboratory between an EBIfungicide and a chloronicotinyl insecticidein the honeybee, Apis mellifera. Pest Manag.Sci. 59:279-286.

Schneider, C.W., J. Tautz, B. Grünewald and S.Fuchs. 2012. RFID tracking of sublethaleffects of two neonicotinoid insecticides on

Moineau, E.R. Bengsch and M.E. Colin.2005. Quantification of imidacloprid uptakein maize crops. J. Agric. Food Chem.53:5336-5341.

Chauzat, M.P., J.P. Faucon, A.C. Martel, J.Lachaize, N. Cougoule and M. Aubert. 2006.A survey of pesticide residues in pollenloads collected by honey bees in France. J.Econ. Entomol. 99(2):253-262.

Colin, M.E., J.M. Bonmatin, I. Moineau, C.Gaimon, S. Brun and J.P. Venmandere.2004. A method to quantify and analyze theforaging activity of honey bees: relevance tothe sublethal effects induced by systemicpesticides. Arch. Environ. Contam. Toxicol.47:387-395.

Cresswell, J.E. 2011. A meta-analysis of experi-ments testing the effects of a neonicotinoidinsecticide (imidacloprid) on honey bees.Ecotoxicol. 20:149-157.

Decourtye, A., E. Lacassie and M.-H. Pham-Delegue. 2003. Learning performances ofhoneybees (Apis mellifera) are differentiallyaffected by imidacloprid according to theseason. Pest Manag. Sci. 59:269-278.

Desneux, N., A. Decourtye and J.M. Delpuech.2007. The sublethal effects of pesticides onbeneficial arthropods. Annu. Rev. Entomol.52:81-106.

Elbert, A., M. Haas, B. Springer et al. 2008.Applied aspects of neonicotinoid uses incrop protection. Pest Manag. Sci. 64:1099-1105.

ENS (Environment News Service). 2008.German coalition sues Bayer over pesticidehoney bee deaths. www.ens-newswire.com

EPA (Environmental Protection Agency). 2008.EPA acts to protect bees. www.epa.gov/pes-ticides

Faucon, J.P., C. Aurieresm, O. Drajnudel et al.2005. Experimental study on the toxicity ofimidacloprid given in syrup to honey beecolonies. Pest Manag. Sci. 61(2):111-125.

Fossen, M. 2006. Environmental fate of imida-cloprid. CA Dept. of Pesticide Regulation,Sacramento, CA. 16 pp.

Girolami, V., L. Mazzon, A. Squartini et al.2009. Translocation of neonicotinoid insec-ticides from coated seeds to seedling gutta-tion drops: a novel way of intoxication forbees. J. Econ. Entomol. 102(5):1808-1815.

Girolami, V., M. Marzaro, L. Vivan et al. 2012.Fatal powdering of bees in flight with par-ticulates of neonicotinoids seed coating andhumidity implication. J. Appl. Entomol.135:17-26.

Henry, M., M. Beguin, F. Requier et al. 2012. Acommon pesticide decreases foraging suc-cess and survival in honey bees. ScienceExpress March 29, 2012. 4 pp.

Hoffman, E.J. and S.J. Castle. 2012.Imidacloprid in melon guttation fluid: apotential mode of exposure for pest andbeneficial organisms. J. Econ. Entomol.105(1):67-71.

Hopwood, J., M. Vaughan, M. Shepherd, D.Biddinger et al. 2012. Are NeonicotinoidsKilling Bees? The Xerces Society forInvertebrate Conservation. Online. 33 pp.

Isawa, T., N. Motoyama, J.T. Ambrose et al.2004. Mechanism for the differential toxicityof neonicotinoid insectides in the honey bee,Apis mellifera. Crop Prot. 23:371-378.

Johansen, C.A. 1977. Pesticides and pollinators.Annu. Rev. Entomol. 22:177-192.

Kievits, J. 2007. Bee gone: colony collapse dis-order. Pesticides News 76:3-5.


Update

There are a few possible draw-backs. Although they can be mostlytroublefree, raising chickensrequires some effort. You have tolike eggs, as each hen tends to pro-duce one egg a day. And there aresome upfront costs in building achicken coop and the chicken run.There are some ongoing costs withpurchase of organic chicken feed.You must also protect your birdsfrom predators, including the familydog.

Chickens? In Berkeley?Backyard chickens are legal now

in many cities. Municipal ordi-nances usually require that chick-ens be enclosed in a coop, and thatthe coop be maintained in sanitaryconditions. Some cities specify aminimum distance from neighbors.Others ban roosters due to thenoise, yet others limit the numberof chickens that can be maintained.Sometimes, chicken enthusiastsstart their projects before they areprotected by an ordinance. Thisoption is outlined in the movie, MadCity Chickens (see Resources).

ProtectionThe chicken coop must be con-

structed to exclude raccoons andpredators. Wooden frame construc-tion with chicken wire is sufficient.Foundations should be constructed

so that critters cannot dig their wayinto your flock (see Resources).Most backyard fowl are healthybecause they are not raised incrowded conditions that depresstheir immune system. Urban veteri-narians are now adapting to thenew reality, and can provide neededvaccinations.

EndgameBefore you start something

involving living beings, it is a goodidea to have an exit strategy. Whatif you decide that chickens are notfor you? What if you have to move?Fortunately, with the upsurge inbackyard operations, many peopleare raising chickens. As chickensget older and die, they have to bereplaced. Typical lifespan is 5-10years. Hens lay for about 3-5 years.Networking with chicken ownerscan keep you in touch with humaneways of dechickening yourself.

ResourcesA Chicken in Every Yard. 2011. Robert and

Hannah Litt, Ten Speed Press, 208 pp.Art of the Chicken Coop. 2011. Chris Gleason,

Fox Chapel Publishing, 161 pp.Chickens in your Backyard. 1976. Rick and Gail

Luttman, Rodale Press, 157 pp.Mad City Chickens. 2008. Tarazod Films,

[email protected] McMurray Hatchery, Webster City, IA

50595; 515-832-3280; www.mcmurray-hatchery.com

Storey’s Guide to Raising Chickens, 3rd ed. 2010.Gail Demerow, Storey Publishing, 448 pp.

Conference Notes

9

9

By William Quarles

There has been a significantresurgence of urban farming in theU.S. A number of books have beenwritten on the subject, and it isbecoming a favorite topic of news-paper journalists. Urban farmersproduce fresh food free of pesticideresidues and pathogens that some-times occur with industrial foodproduction. Backyard food garden-ers have learned that raising theirown vegetables can be fun, and canprovide a way to interact and sharewith neighbors.

Backyard ChickensAnimals have always been an

integral part of organic farmingoperations. And urban gardenersare now taking the next step byraising chickens. There are a num-ber of good reasons to raise back-yard chickens. Chickens in youryard represent a small but signifi-cant step away from factory farm-ing. You can control what yourchickens eat, producing eggs thatare more nutricious than store-bought eggs. The eggs you harvestare fresher, you can eat them thesame day they are laid. Backyardchickens help reestablish the bondwith nature that was broken withindustrial food production.

Backyard chickens can be petsand can be nurtured just like a dogor a cat. Your children will not haveto go to a petting zoo. Chickenmanure can be composted to pro-duce a rich nutritional input forgarden soil. Once gardeners get theidea, they do not have to be eggedon, very little money has to beshelled out, and they very rarelyhave to endure a bad yoke.

Getting StartedWhere do you get your startup

chickens? You can buy them atfeedstores or you can order themfrom hatcheries (see Resources).Hatcheries sometimes have mini-mum orders, so you might have toform a coalition and divide up theorder.

Box 7414, Berkeley, CA 94707IPM Practitioner, XXXIII(1/2) January/February 2011 9

Urban Farming

Chickens are Back in the Backyard

Backyard chickens reestablish the bond with nature that was brokenwith factory farming.

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feed on the blood of warm-bloodedanimals, including humans, poul-try, rabbits, and rodents,” saidPhilip Koehler (Univ of Florida, 970Natural Area Dr, Gainesville, FL32611; [email protected]). They areusually found in aggregations, hid-ing in cracks and crevices. Toobtain a blood meal, bed bugsemerge from their harborages, ori-ent to the host, crawl next to skin,insert their mouthparts, and take3-12 minutes for full blood engorge-ment. (See Don’t let the bed bugsbite, IPMP 32(3/4):1-7)

“After engorgement, bed bugsleave the vicinity of the host, andreturn to their harborages,” saidKoehler. Their cryptic behavioralong with long periods of hiding inrefuges between blood meals makesthem difficult to detect.

At different stages in the feedingcycle, bed bugs are either attractedby host cues or harborage andaggregation cues. The design ofdetection devices must avoid givingthe bed bugs conflicting cues.Conflicting signals may deter bedbugs from entering detectors.

“Carbon dioxide has been shownby several researchers to be themost effective attractant for bedbugs,” said Koehler. Though sta-tionary sources may be best, CO2flushes from CO2 cartridges pro-duce an immediate response, flush-ing bed bugs from their harborages.For example, a CO2 flush gets bed

bugs running from harborages tothe top of a bed.

Bed bugs follow CO2 gradientsto find live hosts. Humans produceabout 700 mg (0.02 oz) of CO2 perminute. “Thus, detectors with veryslow CO2 releases cannot competewith human hosts,” said Koehler. Arapid release is a better mimic tohuman breathing pattern. Detectorswith fast release capture about 4xmore bed bugs than detectors withslow release.

A commercial product, theVerifi™ trap, is a dual-action detec-tor, combining fast CO2 generationwith liquid kairomone andpheromone lures. The CO2 and liq-uid kairomone lures attract hostseeking bed bugs to the pitfall trap,and the liquid pheromone lureencourages aggregation seeking bedbugs to settle in the harborage inthe back of the detector. The signalsare separated, so bed bugs are notconfused.

Early Detection of BedBugs

“Early detection of bed bugs iscritical in order to quickly andeffectively eliminate these pests,”said Susan Jones (Ohio State Univ,2501 W. Carmack Rd, Columbus,OH 43210; [email protected]).

“An inexpensive detector thatcan be left in place and routinelyserviced is needed to aid pest man-agement professionals in effectiveIPM of bed bugs,” said Jones.“Rutger’s do-it-yourself dry ice trapsare a cheap and effective methodfor overnight surveys of potentiallyinfested habitations.” (See Bed bugpheromones and traps IPMP31(5/6):1-8)

“Launched by FMC in October2011, the Verifi™ bed bug detectorprovides a multiple attractor mech-anism combining carbon dioxideand pheromone plus kairomonelures to bring bed bugs into an eas-ily accessible receptacle that can be

10

By Joel Grossman

T hese Conference Highlightsare from the Nov. 13-16,2011, Entomological Society

of America (ESA) annual meeting inReno, Nevada. ESA’s next annualmeeting is November 11-14, 2012,in Knoxville, Tennessee. For moreinformation contact the ESA (10001Derekwood Lane, Suite 100,Lanham, MD 20706; 301/731-4535;http://www.entsoc.org

Attractants formulated into baitscan aid in surveillance and man-agement of ticks and other blood-sucking arthropods. “Tick surveil-lance provides information aboutpopulation densities, geographicspread, and risk of pathogen trans-mission,” said Ann Carr (NorthCarolina State Univ, W.M. KeckCenter, Raleigh, NC 27695;[email protected]). Carr et al. test-ed responses of the lone star tick,Amblyomma americanum, and theAmerican dog tick, Dermacentorvariabilis, to six semiochemicalsattractive to other blood-suckingarthropod species. Possible attrac-tants tested in the laboratory werecarbon dioxide, L-lactic acid, ace-tone, carboxylic acids, nitrogenouswastes, sulphides and 1-octen-3-ol.

“Carbon dioxide, 1-octen-3-ol,acetone and ammonium hydroxidewere attractive to A. americanum,but only carbon dioxide was attrac-tive to D. variabilis,” said Carr.Carbon dioxide (dry ice) consistentlyattracted the highest number ofhost-seeking A. americanumnymphs and adults. However, forthe first time, acetone and ammoni-um hydroxide were shown to attracthigh numbers of A. americanumticks. Acetone and carbon dioxideattracted similar numbers of ticks.

Designing Bed BugDetection Devices

“Bed bugs, Cimex lectularius,are temporary ectoparasites that

Conference Notes

10


Conference Notes

ESA 2011 Annual MeetingHighlights

Bed bug, Cimex lectularius,and eggs

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worked better than lures with onecomponent. A combination of CO2,heat, and a lure was similar ineffectiveness to CO2 plus a lure.Carbon dioxide and lures had anadditive effect.

Carbon DioxideFumigation for Bed BugsCarbon dioxide is used by

libraries, museums, and others asan insect-killing fumigant, saidChanglu Wang (Rutgers Univ, BlakeHall Rm 215, New Brunswick, NJ08901; [email protected]).It can also be an attractant andalter insect behavior. One fumiga-tion methodology is CO2 releasefrom dry ice. Variables governing

efficacy include the concentration,ambient temperature, and insectdevelopmental stage sensitivity.

In lab experiments, 10 nymphs,10 adult males, and bed bug eggswere placed in petri dishes at 25°C(77°F) in incubators with 20% and30% CO2 for 24 hours. Both 20%and 30% concentrations reducedbed bug egg hatch; but statisticalsignificance was not seen until30%, which was deemed the mini-mum concentration for bed bugfumigations to kill the tough eggstage.

A second set of experiments uti-lized 100% CO2 for 2-24 hours at20°C (68°F), 25°C (77°F), and 30°C(86°F). Placing dry ice in the bottomof a flask allowed the evaporatingcarbon dioxide to push out the air;and the flask at 100% concentra-tion was sealed with a stopper asambient temperature was reached.Bed bug mortality at 100% CO2was faster at higher temperatures,at 30°C (86°F) all bed bug eggs werekilled in 3 hours, though it took 8hours to kill the nymphs andadults.

A practical fumigation testinvolved filling plastic garbage bags90% full with mattress covers andfabrics, leaving little room for air;and then sealing the bags with dryice inside. Bed bugs in petri disheswere placed at the top, bottom, and

Conference Notes

11

quickly monitored for activity,” saidJones. A field trial in a 13-storyhigh-rise apartment building inColumbus, Ohio compared: 20rooms with 3 Verifi™ bed bugdetectors per room; 20 rooms withone dry ice trap per room; and 20rooms with canine detection teams.

During the study, 17 of 20rooms had dry ice trap or Verifi™confirmation of a bed bug infesta-tion. The Verifi™ detector found bedbugs in 11 of the 17 infested roomsin the first 24 hours; and in 14 of17 infested rooms within 7 days.The dry ice traps also detected 14of 17 infested rooms. The canineteams reported infestations in 19 ofthe rooms; each dog alerted for bedbugs in 3 rooms where neithervisual inspections, dry ice traps,nor Verifi™ detected bed bugs.Each dog also missed one roomrated positive for bed bugs. In therooms that were bed bug positive,one dog was rated 94% accurate(16/17) and the other dog wasrated 82% (14/17).

Inverted Dog Bowl BedBug Pitfall Trap

Affordable, accurate traps areneeded for monitoring and detectionof low levels of bed bugs, as humanlabor for visual inspections is cost-ly, said Narinderpal Singh (RutgersUniv, 93 Lipman Dr, NewBrunswick, NJ 08901;[email protected]). [Ed.Note: Some inexpensive traps suchas Climbup® are already commer-cially available.]

An inverted dog bowl paintedblack on the outside makes a goodinexpensive pitfall trap, and can becombined with attractants or lures.The inverted dog bowl pitfall trapwas tested in laboratory arenatests. Attractants tested were car-bon dioxide, heat, and chemicallures. Carbon dioxide attracted atall concentrations tested; and wasmore important than heat as anattractant.

Materials tested as bed buglures included nonanol, octanol, 1-octen-3-ol, coriander, andspearmint. In general, lures with amixture of chemical components


Conference Notes

EcoWise is now in the midst ofrenewing the IPM Service Providercertification of our first companies.Hearts Pest Management, an innova-tive company from San Diego ownedand operated by Gerry Weitz, was thefirst to renew. His EcoWise serviceaccounts have increased by 30%since the beginning of the year. Weare also pleased to announce therenewal of Pestec IPM Providers ofSan Francisco, and Applied PestManagement of Vallejo. These com-panies were doing good work beforethey were certified, and we are happythat we can provide a framework torecognize their achievements.

The EcoWise Certified OnlineCourse at www.birc.org continues totrain and certify Pest Management

Professionals (PMPs) in IPM meth-ods. PMPs recently certified onlineinclude Jeff Baerwald, John Chi,David Cole, Scott Conner, GregDorman, Nick Fowler, Gregory Fox,Keenan Gibson, Dave Howard, ScottMcDonough, Richard Mercado,Shaun Miller, Arym Nicado, JustinQuiroz, William Seniff, DavidShouger, Joseph Spencer, and RyanWheeler.

Companies wanting to start anEcoWise Certified service should con-tact BIRC, PO Box 7414, Berkeley,CA 94707 or call us at 510-524-2567 or email us at [email protected] .Part C of the EcoWise CertifiedOnline Course at our websitewww.birc.org also has informationon company certification.

EcoWise News

The Climbup™ bed bug trap

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Calendar Conference Notescenter of the sealed bags. Dry ice at2-3 lbs (0.9-1.4 kg) per garbage bagprovided 100% bed bug mortality in24 hours.

Dry ice fumigation is cheaperthan washing and drying fabrics;and can be used with or withoutheat, depending on the materialsbeing fumigated. Carbon dioxidealone might be useful for books,electronics, toys, and other itemswhere heat might cause damage.However, temperatures can dropquickly as the dry ice sublimates;so several hours in sealed bags(100% CO2) is recommended ratherthan very quick fumigations. Wangrecommends turning on fans forventilation when opening manybags filled with CO2 fumigant. It isalso advisable to wear gloves whenhandling material for fumigations.

Diatomaceous Earth BedBug Alternative

A combination of a chemicaltreatment and two non-chemicalalternatives such as freezing orsteam can cost $500 per apart-ment, and require three treatmentsfor bed bug control, said MollyStedfast (Virginia Tech, Old GladeRd, Blacksburg, VA 24061;[email protected]). It can cost$1,200 per apartment to treat forbed bugs without having any chem-ical residues, which is beyond themeans of low-income people whocannot afford even one $500 treat-ment. Language and literacy barri-ers make bed bug treatments aneven harder sell. Instead residentsresort to dangerous and often inef-fective home remedies for bed bugssuch as bleach, rubbing alcohol,boric acid dust, and total releaseaerosols.

Diatomaceous earth (DE), a sili-ca product mined from fossilizeddiatom deposits and pulverized intoa fine powder for animal feed, filter-ing, and other uses, is relativelysafe and easy to apply compared tomany of the home remedies beingused. DE is porous, absorbingwater; and is also abrasive and adesiccant. Food grade DE is madefrom freshwater diatoms, and isconsidered nontoxic. Filtering grade

DE (used for swimming pool filters)is a crystalline form with inhalationtoxicity. (See Diatomaceous earthalternative to stored product fumi-gants IPMP 28(1/2):1-10)

Food grade DE, which is labeledfor pest control, costs about $8 for8 oz (227 grams), which can treat500 ft2 (46 m2). Thus, a 1,000 ft2

(93 m2) apartment can be treatedwith DE for $32. In lab tests,Safer® and Harris® DEs provided100% bed bug mortality in 5-6days. MotherEarth® D Pest ControlDust and PermaGuard providedfaster bed bug control.

MotherEarth® D Pest ControlDust was tested further to developan application protocol for beds,box springs, under carpets, androom perimeters where bed bugscrawl and can contact the DE. Oncontact, DE becomes embedded inthe bed bug cuticle and causesdeath. A scanning electron micro-scope confirmed that DE becomesembedded in and abrades the insectcuticle. The idea is to use foodgrade DE on places such as mat-tress covers as part of an IPM pro-gram that includes monitoring andother control methods.

Steam Heating Bed Bugs &Dust Mites

The Jiffy Steamer J-4000, whichsells for about $200 and gives digi-tal temperature readings, showedgood potential against bed bugs,Cimex lectularius, and house dustmites, Dermataphagoides farinae,said Roger Gold (Texas A&M Univ,2475 TAMU, College Station, TX77843; [email protected]). The J-4000’s 74°C (165°F) heat provided89% bed bug mortality, with a fewbed bugs escaping the 15 cm (6inch) metal steam head. The treat-ment did not leave any stains orcause bacterial or fungal growth.

Similar good results were report-ed against house dust mites inocu-lated into a mattress; a Traceable™infrared thermometer provided tem-perature readings. Steam head con-tact caused 100% dust mite mortal-ity within 10 seconds; and therewere no problems with stains,molds or fungi. It would take an

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Conference NotesFebruary 23-25, 2012. 23rd Annual MosesOrganic Farm Conference. La Crosse, WI.Contact: Moses, PO Box 339, Spring Valley,WI 54767; 715/778-5775;www.mosesorganic.org

March 4-6, 2012. California Small FarmConference. Valencia, CA. Contact: www.cali-forniafarmconference.com

March 27-29, 2012. 7th Intl. IPM Symposium.Memphis, TN. Contact: E. Wolff, Univ. IL,Urbana. 217/233-2880; email [email protected]

March 30-31, 2012. Beyond Pesticides 30thAnniversary Meeting. Yale, New Haven, CT.Contact: Beyond Pesticides, 701 E Street, SE,Washington, DC 20003; 202-543-5450;www.beyondpesticides.org

June 21-23, 2012. 69th Annual Convention,Pest Control Operators of CA. CatamaranResort, San Diego, CA. Contact: www.pcoc.org

July 5, 2012. Intl. Symp. NematodesEnvironmental Indicators. Ghent, Belgium.Contact: [email protected]

August 4-8, 2012. Annual ConferenceAmerican Phytopathological Society (APS).Providence, RI. Contact: www.apsnet.org

August 5-10, 2012. 97th Annual ConferenceEcological Society of America. Portland, OR.Contact: www.esa.org

October 17-20, 2012. Pestworld, AnnualMeeting National Pest ManagementAssociation (NPMA), Boston, MA. Contact:NPMA, 10460 North St., Fairfax, VA 22031;800/678-6722; 703/352-6762www.npmapest-world.org

November 4-10, 2012. Biocontrol of BacterialPlant Diseases. Agadir, Morocco. Contact:www.lavcha.ac.ma/biocontrol2012

November 11-14, 2012. ESAAnnual MeetingKnoxville, TN. Contact: ESA, 10001Derekwood Lane, Suite 100, Lanham, MD20706; 301/731-4535; http://www.entsoc.org

February 4-7, 2013. Annual Meeting WeedScience Society of America. Baltimore, MD.Contact: www.wssa.net

February 21-23, 2013. 24th Annual MosesOrganic Farm Conference. La Crosse, WI.Contact: Moses, PO Box 339, Spring Valley,WI 54767; 715/778-5775;www.mosesorganic.org

November 17-20, 2013. Annual ESAMeeting.Austin, TX. Contact: ESA, 10001 DerekwoodLane, Suite 100, Lanham, MD 20706; 301/731-4535; http://www.entsoc.org

Conference Noteson the use of pyrethroid insecti-cides,” but “the threat of resistanceis stimulating the search for alter-native methods. ”

“Beauveria bassiana showsgreat potential for development as amicrobial control agent for bedbugs, exhibiting a very fast (4 day)speed of kill,” and “spray residuecan remain potent for up to 3months,” said Barbarin. “Conidiaare acquired via brief contact withsprayed surfaces. Additionally, B.bassiana is equally effective on bothfed and unfed bed bugs, male andfemale bed bugs, and first instarand adult bed bugs.”

Aged Versus Fresh TermiteBaits

Aged versus fresh baits, andeffects of irrigation versus non-irri-gation on baits, are factors to con-sider with subterranean termitebaiting systems such asSentricon®, said Ronda Hamm(Dow AgroSci, 9330 Zionsville Rd,Indianapolis, IN 46268;[email protected]). The Sentriconsystem, which dates to 1990, wasmost recently optimized withRecruit™ HD termite bait. The sys-tem is noted for its durability and ahigh density bait matrix that ter-mites readily consume. (see Baits orbarriers? Field efficacy of IPM ter-mite treatments IPMP 32(9/10):1-9)

A 4-year field study (2007-2011)looked at the baits under conditionsof irrigation and natural rainfall.Laboratory bioassays comparedfresh versus aged field baits.

The trend was a subterraneantermite preference for aged baitsover fresh baits. However, termitepopulation variability was noted“here and there.” Overall, termitespreferred the bait over real worldfood choices. Over the course of 5years, even brown rot and white rotfungal bait degradation did not stoptermite bait consumption or reducebait acceptance or efficacy.

In the field, subterranean ter-mites feed on bait fed on by otherspecies or other termite colonies,said Joe Eger (Dow AgroSci, 2606S. Dundee St, Tampa, FL 33629;[email protected]). In lab trials with

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hour or more to disinfest a king-size mattress with a small steamer.However, steamers could be adapt-ed from other commercial uses;though the economics and treat-ment speeds need to be worked out.

Liquid Nitrogen SprayFreezes Italian Bed BugsBesides conventional chemicals,

Italy uses liquid nitrogen sprays tofreeze pests, the Criopest™ methoddeveloped by Ecotrade (Via Salaria,1428D - 00138 Roma, Italy;www.ecotrade-disinfestazioni.it).Liquid nitrogen sprays for bed bugsworks well where textiles are treat-ed with heat (dry air) and pyrethringels are also used. Pyrethrin gels inbags take 210 minutes for 100%bed bug mortality. Conventionalchemicals are used where residuesare wanted, in locations such aselectric sockets where bed bugsmight hide; but chemicals are only75% effective (in 5 days) againstbed bugs and cockroaches. Hence,the need for an IPM approach. (SeeBed bugs bounce back IPMP29(3/4):1-8)

Ecotrade’s Criopest methodsprays liquid nitrogen at -196°C(-320°F) to freeze bed bugs andother pests. Liquid nitrogen haspercolation effects, penetrating pil-lows and carpets to kill bed bugs.The method is ecologically soundbecause 78% of the atmosphere isnitrogen. The cost is $1.26 eurosper liter (0.94 qt). Hotels like thesystem, because they can rent theroom again immediately. Roomtreatments cost $400-600 euros,and are also guaranteed 100%; 1-2treatments, much less than conven-tional approaches, works well; and80% of clients choose the liquidnitrogen option.

Beauveria bassiana BeatsBed Bugs

“Over the past decade, bed buginfestations have grown almostexponentially in North America andEurope,” said Alexis Barbarin(Pennsylvania State Univ, 525 ASIBldg, University Park, PA 16802;[email protected]). “Current bedbug control measures rely heavily


Conference Notes

Recruit HD bait, previous bait con-sumption by other termites did notaffect palatability. In field trials inDelaware, Florida, and Louisiana,termite bait consumption was high-er on baits previously fed upon byother termites; and a preference foraged over fresh bait was also noted.

These lab and field studies werefurther validated in field testing atthe African American Museum inNew Orleans: Bait fed on by otherspecies or other termite colonies didnot deter new subterranean termitefeeding. Cracks, which are good ter-mite entry sites, may be a factordistinguishing aged baits fromuncracked fresh baits, said Eger.

New Orleans AreawideTermite IPM

Very high densities of Formosansubterranean termite (FST),Coptotermes formosanus, havecaused about $300 million in dam-age in New Orleans and $500 mil-lion in damage in Louisiana,prompting a multi-agency areawideIPM program. The program startedin 1998 in New Orleans and is stillongoing, albeit with fewer privateparticipants since outside fundingwas cut in early 2011, said DennisRing (Louisiana State Univ, 404 LifeSci Bldg, Baton Rouge, LA 70803;[email protected]). “Structureshave collapsed and others havebeen demolished because of dam-age caused by this termite. Thecenters of live trees are eaten by theFST, and trees serve as reservoirs oftermites.”

“Initially, commercially availablebaits or termiticides were used totreat properties in a contiguous 15block area (Area I) in the FrenchQuarter,” said Ring. “Densities ofalates (winged termites) were sam-pled using glue boards hung onstreet lamp poles near lights,” saidRing. “Alates were sampled once aweek in April and 2-3 times weeklyduring the flight season (Maythrough July 15) in 1998 through2011. Alate numbers were reducedby 50-75% following treatment, andthe lowest numbers of alates werecaptured in 2011. Funding for theprogram ended in early 2011. Some

property owners are choosing not torenew their termite contracts.Therefore, some treatments arebeing discontinued.” Alate trappingnumbers, a measure of treatmentsuccess (fewer flying FST indicatelower FST populations overall in thearea), are expected to increase incoming years with lower programparticipation.

Borate Fire Ant BaitsNiban™ Granular Baits have the

advantage of being among the mostresistant to water, weather, andmolds, said Janet Kintz-Early(Nisus Corp, 100 Nisus Dr,Rockford, TN 37853; [email protected]). Granular bait formula-tions were compared with and with-out active ingredients (includingborates) and with different attrac-tants in an effort to overcomeborate repellency.

Granular bait field tests inGeorgia and Texas to gather datafor EPA submission were conductedfor 90 days on 1/4-acre (0.1 ha)plots with 10 red imported fire ant,Solenopsis invicta, mounds perplot. Treatments included: AMDRO(hydramethylnon and methoprene);Niban A (5% boric acid); Niban B(methoprene); and untreated con-trol.

AMDRO peaked at week 13 with81% control. Niban A boric acidbait provided 39% control at week 8when rain washed off the borates(which have a little fertilizer valuefor the soil). Niban B methoprenebait provided 74.4% control at 13weeks.

Argentine Ant TrailPheromone DisruptionArgentine ant, Linepithema

humile, trail pheromone, (Z)-9-hexadecenal, is a commercial chem-ical that is also a moth pheromone,which means it is readily availablefor IPM programs, said MaxSuckling (New Zealand Instit ofPlant and Food Res Ltd, PB 4704,Christchurch, New Zealand;[email protected]).Argentine ant trail pheromone dis-ruption work began in Hawaii’s eco-logically-sensitive Volcano National

Park, spurred in part by Tatsuki etal.’s (2005) demonstration thatArgentine ant trails in orchardscould be partially disrupted byrelease of (Z)-9-hexadecenal frompolyethylene tubing dispensers.

At Japan’s Port of Yokohama, anIPM approach combining pesticidesand Shinetsu twist-ties to disruptant trails is said to be successful;though the mechanism is unknown.Another strategy is using trailpheromone to paint a trail leadingsomewhere else; for example, anartificial trail leading off the maintrail towards baits. These potentialIPM strategies using trailpheromones need more testing.

Bullet Ant, World’s MostPainful Sting

The world’s most painful sting-ing insect, Paraponera clavata, thebullet ant, gets its common namebecause its sting feels like a bulletripping through you, said JustinSchmidt (Southwestern BiologicalInstit, Tucson, AZ 85720;[email protected]). On a 1-4pain scale, bullet ants rate a 4because of the 12-24 hours ofintense pain from stings. Harvesterant stings rate a 3, as they canhurt for 4-8 hours. A honey beesting rates a 2. One fire ant stingrates a 1.

One of the world’s largest ants at18-24 mm (0.7-0.9 in), the bullet antlives in colonies of about 3,000 andis native to the tropical Atlantic coastof the Americas from Nicaragua tothe Amazon basin. Bullet ants arepredators and nectar feeders in therainforest canopy. Mass spec-troscopy of bullet ant venom indi-cates two peptide peaks very similarchemically to poneratoxin.

Conference Notes

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Conference Notes

Argentine ant, L. humile

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