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GENERAL NOTES JournaloftheLepidopterists'Society 51(3), 1997,249-256 NOTES ON THE SESIID FAUNA OF SOUTHWESTERNWESTVIRGINIA Additional keywords: pheromones, faunalsurveys, Appalachian region. The Sesiidaeis arelativelywellstudiedmothfamily. Inthepastcentury, threecompre- hensive monographs have been written on the group (Beutenmuller 1901, Engelhardt 1946, Eichlin & Duckworth 1988), and several regional surveys have been conducted in the eastern United States (Neal et al. 1983 in Maryland, Sharp et al. 1978 in Florida, Sharpetel. 1979againinFlorida, Snowetal. 1985inGeorgia, Solomonetal. 1982in Mis- sissippi, andTaft & Snowin 1991 in the north central United States). These studieswere aided enormouslybythe chemical isolation and synthesis offemale sesiid sex attractants. In 1974the synthesis ofthe (Z,Z)-3,13-octadecadien-l-ol acetate andofthe (£,Z)-3,13-octadecadien-1-ol acetatewas achievedbyTumlinsonandYonce respectively, andin 1983 the (E,Z)-2,13-octadecadien-l-olacetatewasisolatedbySchwartz(Eichlin&Duckworth 1988). The useofthesepheromones, alone orin different combinations, in the acetate oralcohol forms,hasbecome theprincipal methodforcollectingmale Sesiidae andhas ledtothe dis- coveryofmanynewspeciesandtotheelucidationofdistributions andflightpatterns. ThepurposeofthepresentstudyistoestablishthenumberofSesiidaespeciesflyingin southwesternWestVirginia, and to report on male responsiveness to different synthetic pheromone isomers in"pure" form andin differentcombinations. Samplingwasconductedoveraperiodoffiveyears, startingin May 1990andendingin September 1994. Seven locations in two counties were sampled: five in Kanawha County and twoin adjacent Putnam County. Three ofthe Kanawha Countylocations are situated inthecityofCharleston (South Hills, KanawhaCity, Coonskin Park). Kanawha State For- estislocatedatthe southernboundaryofthe city, andTupperCreekis asmallruralcom- munity 10 miles north ofthe city. The South Hills and the Kanawha City locations are denslypopulated urban areas, with occasionalpatches ofoakwoodland. Coonskin Parkis apartiallydevelopedhilltopthatiswelldrained and ratherdry. In addition to the decidu- ous trees typical forthe area, it contains alarge population ofold pines. Kanawha State Forestis alarge tract ofundeveloped landcontainingavarietyofmicrohabitats including gulches, ridges, riverbottomsandhillswithlargetractsofdeciduous forestinterruptedby small clearings. Tupper Creek is a disturbed area along a small creekwith an extensive growthofwillowtrees. Ofthetwo Putnam Countylocations, oneis situated20 mileswest ofCharlestononafirtreefarm, andissurroundedbyhillsofuninterrupteddeciduousfor- est. The othersite, located 25 mileswest ofCharleston, is a disturbed areaon the south bankofthe Kanawha River,which supports an extensive growth ofwillow. I used Multipher I traps and lures supplied by the IPM Great Lakes Company (Vestaburg, MI). The lures used in this studyare listed in Table 1. In the traps I placed DDVP toxicant strips providedby IPM Great Lakes. In 1990, five traps baitedwith 97:3, ZZA, EZA, 1:1, and TRI lures were deployed in the South Hills area ofCharleston. In 1991, eight traps baited with 97:3, ZZA, EZA, TRI, EZ-2,13-OH, EZ-2,13-A, EZ-3,13- OH, and99:1 were used on the fir farm in Putnam County. In 1992, 2. eight traps baited with 97:3, EZA, ZZA, 1:1, TRI, 99:1, and EZ-3,13-OH were usedin Kanawha State For- est. In 1993, five traps baited with 97:3, ZZA, EZA, 1:1, and 99:1 were used at Tupper Creek and three traps with 97:3, EZA, and ZZA in Kanawha State Forest. In mid June 1993, the 1:1 and 97:3 trapswere moved from TupperCreekto South Hills and the 99:1 trapto Kanawha State Forest.Then,inmidAugustalltrapsweremovedto KanawhaCity. In 1994, three traps baited with 97:3, ZZA, and EZA were used on the Kanawha River shore; threetraps baitedwith 97:3, ZZA, and EZAin Coonskin Parkandtwotraps baited with 1:1 and 2:1 in Kanawha City. At the beginning ofAugust, the three Putnam County trapswere movedto KanawhaCity. I began each baiting season in May, when theweatherwas reliablywarm, and ended trappingin late SeptemberorearlyOctober. Inthe middleofJulyIaddedanewlureload toeachtrap, makingsurethateachtrapcarriedthesamelurethroughouttheseason;new 250 Journal of the Lepidopterists' Society Table 1. Pheromonal lures used in the present studyand their abbreviations. Small percentages ofimpurities are omitted (these should be less than 1% with current synthesis techniques; Tumlinson 1979). 97:3 97% (Z,Z)-3,13-octadecadien-l-ol acetate/3%(E,Z)-3,13-octadecadien-l-olacetate ZZA 100% (Z,Z)-3,13-octadecadien-l-ol acetate EZA 100% (E,Z)-3,13-octadecadien-l-olacetate 1:1 50:50 mixture of(Z,Z)-3,13-octadecadien-l-olacetate/ (E,Z)-3,13-octadecadien-l-olacetate 99:1 99:1 mixtureof(E,Z)-2,13-octadecadien-l-olacetate/ (Z,Z)-3,13-octadecadien-l-ol acetate EZ-2,13-OH 100% (E,Z)-2,13-octadecadien-l-ol EZ-2,13-A 100% (E,Z)-2,13-octadecadien-l-olacetate EZOH 100% (E,Z)-3,13-octadecadien-l-ol TRI 20:1:3 mixtureof(Z,Z)-3,13-octadecadien-l-olacetate/ (E,Z)-3,13-octadecadien-l-ol/acetate (Z,Z)-3,13-octadecadien-l-ol 2:1 2:1 mixture of(E,Z)-3,13-octadecadien-l-olacetate/ (E,Z)-3,13-octadecadien-l-ol toxicantvaportapeswereaddedatthe sametime. Trapswereplacedontreebranches, ei- ther at the edge ofthe forest oron solitarytrees, in clearings, at 1-1.5 m above ground with at least 20 m distance between traps. Wheneverpossible the trapswereplaced in a south or southwest orientation. I visited each trap once aweekand emptiedthe buckets intolabeledstyrofoam cupsthat I tookhometo recordthe attractedspecimens. Duringthis study5080malesesiidswerecaptured, representing24speciesin8genera. Two ofthese, Synanthedon kathyae Duckworth & Eichlin andAlcathoe carolinensis En- gelhardt, are new records for the state ofWest Virginia (T. D. Eichlin, pers. comra.). Melittia cucurbitae (Harris) was neverlured to apheromone trap butwas netted on the foodplant (zucchini squash); since the main purpose ofthis studywas to record as many species as possible for this area, I included it in the present listing. Table 2 lists all the recorded species, showing theiryearly abundance at the sample sites. Table 3 gives the monthlydistributions and abundances, andTables 4-5 summarize the sensitivityofmale sesiids tothe differentpheromonelures inthis study. Geographical and temporal trends. The records ofSynanthedon pictipes (Grote & Robinson), Podosesia aureocincta Purrington & Nielson, Carmenta bassiformis (Walker) and Synanthedon rileyana (Hy. Edwards) showwide year toyear fluctuations. Sincethese fourspecies have atleastone generationperyear (S.pictipes is multivoltine), these fluctuations were probably geographical rather than temporal: one year the traps happenedtobeplacedinsidetheterritoryofapopulationandattractedalargenumberof individuals; anotheryeartheywere outside the population's territoryand attracted fewer individuals. The numberofattracted specimens suggests that these species are abundant insidewellcircumscribedcolonies,whicharedoubtless centeredaroundtheirfoodplants. Synanthedon rubrofascia (Hy. Edwards), Synathedonscitula (Harris), Synanthedonde- cipiens (Hy. Edwards), Synanthedonfatifera Hodges and Carmenta ithacae (Beuten- muller) had similar yearly/geographical fluctuations, but their numbers suggest much smallerand even more circumscribed colonies. It isworth notingthe difference in abun- dancebetween Synanthedon exitiosa (Say) and S. pictipes. While these species both uti- lizewild and cultivated Rosaceae as hosts (Snow 1985, Eichlin 1988), S. pictipes appears to be much less abundant and more localized in southwestern WestVirginiathan S. exitiosa. The records forParanthrenesimulans (Grote) andParanthrenepellucida Greenfield& Karandinos confirm theirtwo-yearlife cycle, with peak numbers being attractedin odd years. In the studyarea, both species appearto have similarabundance, bothpeakin the Volume 51, Number 3 251 Table 2. Yearlyoccurence ofsesiid species in southwesternWest Virginiabasedon captures inpheromonebaitedtraps. Species Total 1990 1991 1992 1993 1994 Podosesiasyringae 1564 67 613 176 488 220 Synanthedonexitiosa 1229 213 168 159 353 336 Podosesiaaureocincta 651 3 93 547 7 1 Synanthedonpictipes 519 113 142 9 41 214 Carmentahassiformis 235 6 2 56 147 24 Paranthrenesimulans 181 89 4 87 1 Paranthrenepellucida 170 5 95 2 65 3 Alcathoecaudata 127 120 5 2 Synanthedon ruhrofascia 115 33 3 1 17 61 Synanthedon rileyana 110 2 105 2 1 Synanthedonscitula 53 1 25 25 1 1 Synanthedonfatifera 29 2 14 13 Carmentaithacae 20 3 17 Synanthedon acerni 13 2 2 9 Synanthedon acerruhi 12 11 1 Synanthedondecipiens 12 2 10 Sanninauroceriformis 12 12 Synanthedon viburni 11 3 1 7 Synanthedon rhododendri 8 1 7 Synanthedon kathyae 3 3 Vitaceapolistiforrnis 2 2 Alcathoecarolinensis 2 1 1 Vitaceascepsiformis 1 1 Mellittiacucurhitae 1 1 sameyears, andtheirtwo-yearcyclesoccurredinoddnumberedyears, contraryto Engel- hard's statement (Engelhardt 1946:146) that even numberedyears have peakflights ofP. simulans in eastern United States. Table 3 shows that the mostproductive monthswereJune andJuly. Allbut one ofthe 24 specieswerecaughtduringthesetwo months, the exceptionbeingthe later-flyingP. aureocincta. Table 3 also shows distinct temporal segregation ofPodosesia syringae (Harris) andP.aureocincta,thefirsthavingpeakflightin Mayandthelatterreachingpeakflightin September. This lackofoverlapis similartootherreports (Eichlin & Duckworth 1988) of anApril-MaypeakforP. syringae andapeakafterJulyforP. auroecincta. The closelyre- latedP. simulans andP. pellucida also showed asegregation in flightperiods. P. simulans hadpeakflightin May,wherasP.pelludicapeakedinJune. Unfortunately, duetounfavor- ableweather, Ineversettraps uppriorto May;therefore Ilackdataabouttheresponsive- ness ofP. simulans to sexattractantsinevenearliermonths. ThephenologyforS. pictipes suggests two generations peryear, with amore abundant springgenerationin MayandJune (probablystartingearlier) andalessabundantsummer generation from Julythrough October. This species is the onlyone thatcame to the traps ineachmonthofthe study. S. exitiosa hadanextendedflightseasonaswitnessedbyother authors (Eichlin & Duckworth 1988, Snowet al. 1985). S. ruhrofascia exhibited a similar pattern, with a flight period extending from Mayto September and apeakin July. This matchesthe datareportedbySnowetal. (1985),whowereabletocapturethe mothfrom Aprilto Novemberin central Georgia. Eichlin and Duckworth (1988) give ashorterflight period (May andJune). The specimens capturedin this studydid not resemble the illustration given by Eichlin and Duckworth in their monograph ofthe Sesiidae, but, having completelytransparent forewings, theymatched the illustration given byTaft and Snow (1991). 252 Journal of the Lepidopterists' Society § 8. to "-C § a. n h in oo oho ro co 10 oq cq CD 03 I «s I -o I CD § 8 § 2 i-2 c o 0^ co -< CO co bTf^lOCD^HOW ^ ^H ^H OlOJCD^FOqr-lrH^H cq o c o -2 « 3 t3 8 S oo CJ *> a ^8 3 £ c =8 1 S 8 *§ ^ -g S s +4 '5b co^cÛcocococoex;Ococo ONOoooaominioioncoM coc005t^m-^cO^ CO rH 8 8 £ .-S ^ ~ £ -* ••§ §J^to=5^.is-8^ § £ §Jj*§ b 2 §~s coOcocoi^cocoOco^f^coco^co^cd^^; (MOJNOOHTjiNONCOWCOCONH oC^qO CcCTqO> 05t—(inC<|(M^ l—I .—I 3 (^coco(^^cocoOcoco'cococo'cococoO-< o o o t^coôoooineqoq^^H cq co cq c o 5 £88 2 2 to 8 8to tao ^Ss^3S Vtao cx;coO»icocococococo i Volume 51, Number 3 253 &0Caa3O*Soos ~~ I |. rt I I I 2 I I I | | | | » | | | | | ca 2o )cH 5+CHO C03O 18 IS || rSt *0o3 I I I I I I I I I I I I I I I I | | T£3 Dh G G 0>3 M MS N t-H 'a5b I I l~ I I I | | |».|$-| | | | S& j^ E CO g 13 G 3 XI i4Hi V II IS 18 II 'B I I I I I I I I I I I I I I I I c <D o Ih I03f,£EG0)3 I I I I rtt0rH I I I I I I IS I I 13 I I I I I G fl Cob ,_c,a I3hj o 0P3hH03 °"D g 1*1 iggg rt i i i i i i i i i i i co 03 Ih Ôqj aCjO I I z5G -0OC^3JO Hs i»« rt g r iTi co 0a3 i i r i i i i i i i _IGh aIh* 0GEC3 "20G~3 -c2Dom"^ 1*M05^tDNO iHcqNlO |(C I I CO I W CO I I I I p ^03Z J ^^Wc<> oE0C3 * I Sfc ^ I 1^8 I 81 I I IS I I IS. I I G E 3 h rg £ ^ CO M 5+CO0HO3 -0Ga3 -'c<-GU' pH05HCO(OONCO |HTf |ini I I tON(M I I I en ^ G 0G3 g^ 0>3 1—1 .2 gCco £ ^& 4-. -C3COj §1 ^^ e Ih CO <n <n rL §2-^ *w cEox5 io s * ^ s> rhJ3<2 "cCG-oO''C^CI3H I -1 g sr 11^ J^) 1Q iC'g|1& 8 E E I f §"g^S HI ^c^ft^cÛft^^^'cîc^c^cÛc^coc^cyic^cyic^^^^^ 254 Journal of the Lepidopterists' Society TABLE5. Comparisonofresponsivenessofsesiidspeciestodifferentpheromonelures inthree different studies. Present Eichlin& Taft& Species Study Duckworth,(1988) Snow,(1991) P. syringae 97:3, ZZA ZZA ZZA S. exitiosa 97:3, ZZA ZZA ZZA P. aureocincta 97:3,TRI, ZZA TRI ZZA, 50/50ZZA/EZOH S. pictipes EZA EZA EZA C. bassiforrnis EZA ZZA, ZZOH ZZA, 50/50ZZA/ZZOH P. simulans 97:3, EZ-2, 13-A 96:4, ZZA ZZA, 99:1 P. pellucida 97:3, ZZA no mention ZZA A. caudata TRI no mention ZZOH, 1:1 S. rubrofascia 1:1, 2:1 EZA/EZOH 1:1 1:1 S. rileyana EZ-2, 13-OH EZOH, EZOH, 50/50 EZOH/EZA ZZA/EZOH S. scitula EZA ZZA ZZA S.fatifera ZZA, 97:3 ZZA ZZA C. ithacae EZA ZZA, 97:3 EZA S. acerni ZZA, 97:3, light ZZA, light ZZA, 50/50ZZA/ZZOH S. acerrubi 99:1 EZ-2, 13-A 99:1 S. decipiens 97:3, ZZA ZZA/EZA, ZZA, 1:1 ZZA/EZOH S. uroceriformis EZ-2, 13-OH EZOH, no mention EZOH/ZZOH S. viburni EZA EZA EZA S. rhododendri 97:3, ZZA ZZA no mention S. kathyae EZOH, ZZA ZZA no mention V. polistifonnis 99:1 99:1 99:1 A. carolinensis EZA, 1:1 EZA, 3:1 no mention V. scepsiformis 99:1 ZZA/EZA, no mention ZZA/EZOH M. cucurbitae on foodplant 99:1 99:1 Synanthedon acerni (Clemens) and Synanthedon acerrubi Engelhardt had a shorter flightperiod than given by other sources (Eichlin & Duckworth 1988, Snow et al. 1985, Taft& Snow 1991). Bothspecieswereactiveonlyin MayandJune. Sanninauroceriformis Walker was active in May and June (see Eichlin & Duckwoth 1988, Snow et al. 1985). Synanthedonviburni Engelhardthadamoreextendedflightperiod (MaythroughAugust) than S.fatifera, which was active almost exclusively in June. S. scitula, S. rhododendri (Beutenmuller), S. rileyana, S. decipiens, C. bassiforrnis, C. ithacae andAlcathoecaudata (Harris) had flight periods similarto those observedbyother authors (Eichlin & Duck- worth 1988, Snow et al. 1985, Taft & Snow 1991). A. carolinenesis had an earlieractivity period (June andJuly) comparedtoothersources (Eichlin & Duckwoth 1988, Snowetal. 1985, Sharp et al. 1978). This is somewhat surprising, consideringthat both Snows and Sharp's groups collected their specimens to the south of West Virginia (Georgia and Florida, respectively). The flight of S. kathyae corresponded with the period given by Eichlin and Duckworth (1988), as did that ofVitacea polistifonnis (Harris) and Vitacea scepsiformis (Hy. Edwards). Pheromonal responses. The 97:3 blendproved to be the most generalized attractant, yielding a total of15 species. Itwas the main lure forseven species: S. exitiosa, P. pellucida, P.syringae, S. decipiens, S. rhododendri, P. aureocincta andP.simulans. Italso attracted a large percentage of all S.fatifera, S. viburni, S. acerni and S. scitula. The "pure"ZZAlurealsoattracted 15 speciesbutwasthe main attractantforonlytwospecies: S.fatifera and S. acerni (note that 38% ofS. acerni individualswerecaught atblacklight, usuallyearlyin the morning; thiswas the onlyspecies thatcame toblacklight duringthis Volume 51, Number 3 255 study, see Eichlinand Duckworth 1988). The"pure" EZApheromonewas attractiveto 11 species; for six ofthose it was the main attractant: C. ithacae, S. pictipes, S. scitula, C. bassifonnis, S. viburni andA. carolinensis. Surprisingly, theTRI mixturewas onlymoder- ately attractive for P. aureocincta, forwhich it was originally formulated (Nielsen et al. 1979), attracting only 21% ofthe 651 individuals ofP. aureocincta caught. In contrast, 59% ofthe individuals responded to the 97:3 mixture. Sharp and Eichlin reportthe same weakattraction ofthis combination forP. aureocincta (1979). The TRI lure proved strongly attractive toA. caudata (92% ofthe total). A. caudata displayedaspecificpheromone responsiveness: of120 specimens caughtin 1990in South Hills, 117 responded to the TRI luredtraps and onlythree to the 97:3 traps. In 1991 no individuals came to the TRI trap in Putnam County. In subsequentyears I did not have theTRI lure,butthe97:3lureattracted5and2individuals respectivelyin KanawhaState Forest and Tupper Creek. This suggests that A. caudata occurs in large, well circum- scribedcolonies, andtheindividualsexhibitastrongattractiontotheTRI mixture. Synan- thedon acerrubi Engelhardt and Sannina uroceriformis Walker exhibited the same geo- graphicalconfinement,butthenumberscaughtindicate smallcoloniesorweakresponses. The 1:1 mixtureattractedS. rubrofascia (76% ofthetotal). The99:1 blendluredalltheV. polistifomiis and V. scepsiforrnis caught andwas highlyattractive for S. acerrubi (83% of thetotal). EZ-2,13-OHwas ahighlyspecificlure for S. uroceriformis, (100% ofthetotal). Italsoprovedattractiveto S. rileyana (83% ofthetotal). The EZOH isomerwas aless ef- fectiveattractantforS. rileyana (10% ofthetotal), andluredtwoindividualsofS. kathyae (66%). No M. cucurbitae males were attracted to any pheromone traps, even though a 99:1 baited trap was kept close to the patchwith zucchini-squash plants, where the only individualcaughtduringthis studywas netted. Table 5 summarizes male sesiid responsiveness to different sexlures in three different studies: the presentwork, Eichlin and Duckworth (1988) and Taft and Snow (1991). In the present studyC. bassiformis exhibited a strong affinitytoward the EZA lure (77% of thetotal),whereastheothertwostudies reportedtheZZAisomeras mostattractive. Since thesewere the same EZA baited traps that attracted 94% ofS. pictipes individuals, and since it is known that the presence ofas little as 1% ofthe ZZA isomer as an impurity would significantlyreduce the response ofthe moth to the lure (Tumlinson 1979), it can be concluded that the EZA lure usedin this studywas ofhigh purity. The same scenario occurred with S. scitula: 80% ofthe individuals in the present study came to the EZA traps,while the other studies found the ZZA isomertobe the main lure. Itwouldbe in- terestingto find out ifcircumscribed and geographicallyisolated populations ofthe same species couldbe responsivetodifferentpheromoneisomers (thereis someindicationthat attractancyto pheromones or mixtures mayvarydepending onwhat other species flyin the same area; Eichlin, pers. coram.). In conclusion, with 24 species recorded here, southwestern WestVirginia appears to have a rich sesiid fauna. Further collecting will doubtless add more species to the list (whilethis paperwas beingprepared, a male Synanthedan sigmoidea (Beutenmuller)was takenat KanawhaCityina99:1 trap). Theabundancedatareportedhereshouldbeinter- pretedwith caution: pheromone bait trap captures ofmales in specific locations mayor maynot reflect the overall abundance ofparticular species in the whole region. Forin- stance, M. cucurbitae is certainlyacommon species in southwesternWestVirginiawhere hostplants are available, yet no individualwas caughtin anyofthe baitedtraps. Itwould beerroneous toconclude from this studythatM. cucurbitae is arare species. Acknowledgments IthankThomas Eichlin foridentifyingsomeofthemoredifficultspecies, andforoffer- ing constructive criticism on the manuscript; Hermann Flaschka provided some ofthe more specific sexattractant samples; ClaudiaThomas helped edit andprepare the paper. ThispaperwaspresentedinpartattheAnnual MeetingoftheWestVirginiaEntomologi- cal Societyon6January 1995. Literature Cited W Eichlin, T. D. & D. Duckworth. 1988. Sesioidea: Sesiidae. In Dominick, R. B. et al., The Moths ofAmerica NorthofMexico. Fasc. 5.1. 256 Journal of the Lepidopterists' Society ENGELHARDT, G. P. 1946. The NorthAmericanclearwingmoths ofthe familyAegeriidae. U. S. Natl. Mus. Bull. 190:146. NEAL, J. W, Jr. & T. D. ElCHLIN. 1983. Seasonal response ofsix male Sesiidae ofwoody ornamentals to clearwing borer (Lepidoptera: Sesiidae) lure. Environ. Entomol. 12:206-209. Nielsen, D. G., F. F. Purrington & G. F. Shambaugh. 1979. EAG and field responses of Sesiidae males to sex pheromones and related compounds. Proc. Symposium Pheromones ofthe Sesiidae, USDA, SEA, ARR-NE-6:ll-26. SHARP, L. &T. D. ElCHLIN. 1979. DistributionandseasonaloccurenceofSesiidae(Lep- J. idoptera) attractedto E,ZandZ,Zacetateandalcohol. Proc. Symposium Pheromones ofthe Sesiidae, USDA, SEA, ARR-NE-6:35-46. Sharp, J. L., J. R. Mclaughlin,J. James,T. D. Eichlin &J. H. Tumlinson. 1978. Sea- sonaloccurenceofmaleSesiidaeinnorthcentralFloridadeterminedwithpheromone trapping methods. FloridaEntomol. 61:245-250. Snow, W., T. D. Eichlin & H. Tumlinson. 1985. Seasonal captures ofclearwing J. J. moths (Sesiidae) in traps baitedwithvarious formulations of3,13 octadecadienyl acetate andalchol. Agric. Entomol. 2:73-84. Solomon, D., F L.J.Oliveira, H. Tumlinson & R. E. Doolittle. 1982. Occurence J. J. of clearwing borers (Sesiidae) in west central Mississippi. Georgia Entomol. J. 17:4-12. Taft, W. H. & W. Snow. 1991. A guide to the clearwingborers (Sesiidae) ofthe north J. central United States. North Central RegionalPublication394. TUMLINSON, H. 1979. The chemistry of Sesiidae pheromones. Proc. Symposium J. Pheromones ofthe Sesiidae, USDA, SEA, ARR-NE-6:1-10. Valeriu Albu, 6KitRoad, Charleston, WestVirginia25314, USA. Receivedforpublication 5 October1995; revisedandaccepted18April1996. JournaloftheLepidopterists'Society 51(3), 1997,256-263 MIGRATORYACTIVITY IN VANESSA CARDUI (NYMPHALIDAE) DURING 1992 IN WESTERN NORTH AMERICA, WITH SPECIALREFERENCE TO EASTERN CALIFORNIA Additional keywords: migration, populationdynamics,weather, OwensValley. Migrations ofVanessacardui (L.)were unusuallylargein southwestern NorthAmerica during 1991-1992, the largest since 1968 and 1973, providing a rare opportunityto study the complex mass behavior andpopulation dynamics ofthis species (cf. Woodburyet al. 1942, Abbott 1951). Herewesummarize 1992records forthe regionandpresentobserva- tions made byone ofus (DG) in Inyo County, California. The methods followthose out- linedin Giuliani and Shields (1995). Migration rates here (no./5min/15m) are arbitrarily classifiedaslight(1-29), small-scale(30-49), medium-scale (50-99)andlargescale (>99). Vanessa cardui, like the monarch (Danaus plexippus L.), has a southward return migration duringthe summerand fall (Emmel &Wobus 1966, Shapiro 1980, Myers 1985, Nel- son 1985, Giuliani & Shields 1995). Small numbers ofmigratingV carduiwere reported during Februaryand March 1992 NW NNW in California, including: at Hemet (29 February, 12-22 March), in San Diego NW-WNW NNE-WNW County (9-10 March), near Bakersfield (11 March), in Inyo County(15-17 March), andWSWinVenturaCounty(19 March) (pers. obs.; F Emmel, in litt; McKown 1993). A light migrationwas seen between BarstowandYucJc.aValleyon 26 March (McKown 1993). Manynorthward migratorswere seennear San Diego (27-30 March) (R. Larson, pers. comm.), andtherewere severalnewspaperaccounts ofV cardui plasteringwindshields duringlate Marchinthe southern SanJoaquinValley.