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Vol. 104, No. 3. May &June, 1993 123 A HUGE NEST OF THE COMMON YELLOWJACKET, PARAVESPULA VULGARIS (HYMENOPTERA: VESPIDAE), IN CALIFORNIA1 RogerD.Akre, Elizabeth A. Myhre,Yi Chen2 ABSTRACT:Alarge,perennialcolonyofParavespulavulgariswascollectedinCalifornia inJuly 1992.Theenvelopewasca97diam and had multipleentrances.Thecolonycon- sistedof220nonfunctionalqueens,2developingqueens, 10functionalqueens,ca84,000 workers,andca 32,000males.The22combsconsistedofca220,000workerand9,000re- productivecells;64%wereempty.Thecolonywasestimated tobe2-3 yearsold. Yellowjacketstypicallyhaveaoneyearlifecycle,and theonlymem- bersofthecolonytooverwinterareinseminatedqueens.Theystart new colonies in the spring. However, some colonies continue for more than one season (Akre and Reed 1981) and these colonies are always poly- gynous (Carpenter 1989). Large, perennial colonies have previously been reported forParavespulagermanica (F.) in New Zealand (Thomas 1960, Plunkettetal. 1989, Clapperton etal. 1989), Tasmania (Spradbery 1973a), Algeria and Morocco(Vuillaume<?fal. 1969), andChile (Jeanne 1980, Chiappa et al. 1987). Perennial colonies are unusually large, and Spradbery (1973a) estimated one nest weighed 1,000 pounds. Vespula squamosa(Drury),thesouthernyellowjacket, hasperennialcolonies in the southern United States, especially in Florida (Tissot and Robinson 1954,Akreetal. 1981, Ross and Matthews 1982)and inTexas. Perennial coloniesofthecommonwaspoccurinNewZealand(Plunketteral. 1989) andaperennialcolonyofP. vulgaris(L.)wasrecordedinCaliforniayears ago(Duncan 1939).Unconfirmedreportsindicatemanymoreperennial colonies are being found in southern California where winter tem- peratures are mild, and prey populations are high enough to sustain a colonythroughthewintermonths.OneP. vulgariscolonypersisted from its discovery in 1984 until at least 1986 in Berkeley, CA (Alameda Co.) A (Gambino 1986). two year colony ofP. pensylvanica (Saussure) was reported in British Columbia (Spencer 1960), and Nakahara (1980) recordedahugeperennialcolonyofP.pensylvanica(Saussure)inHawaii (see also Gambinoetal. 1990). The purposeofthis paperis to present a detailed analysis ofa nest off*, vulgaris collected in Burlingame (San Mateo Co.), California. 1 Received November21, 1992.AcceptedJanuary2, 1993. 2 DepartmentofEntomology,Washington StateUniversity.Pullman,WA99164-6382. ENT. NEWS 104(3): 123-128. May&June, 1993 ENTOMOLOGICALNEWS 124 MATERIALS AND METHODS A large nest ofParavespula vulgaris was discovered in Burlingame, California,andalocalpestcontrolfirmwascalledtokillthecolony(Fig. m 1). The nest was built into a dense mass ofvines hanging 1.2 to 1.5 Fig.1.Thenestwassuspendedinalargemassofvines.Althoughtheentranceholesarenot readilyapparent from this angle,several wereatleast4cmdiam(R. Schoeppnerphoto- graph). Vol. 104,No. 3,May&June, 1993 125 above a creek bank. The nest was ca 62 cm wide X 76 cm tall X 35 cm thick, with a circumference of244 cm, a diameter of97 cm (measure- mentswereestimatedfromaphotograph),somewhatheart-shaped,and had multiple entrances(ca 120on each side).Thecolonywas killedthe weekof12July1992,andallnestmaterialandoccupantswereshippedto WashingtonStateUniversityatPullmanforstudy.Thenest,ascollected, completewith severedvines,weighedca 64kg. The nestwas stored ina freezer at 5.0 F until the occupants and combs were counted and analyzed. Males were individuallycounted first, and itwas determined that 1,385 fit into a 250 ml graduate cylinder when it was vigor- ouslytappedonthesubstratetosettleandcompactthem.Thecountwas stopped when they no longer settled. Similarly, 2,01 1 workers were needed to fill a 250 ml cylinder. All remaining individuals, except queens, were measured volumetrically to estimate number ofworkers and males inthecolony.Queenswereindividuallytallied,injectedwith Kahle'stopreservethem,andplacedinto70%ETOHuntiltheyweredis- sected for ovarian development. All combs ofthe nestwere analyzed forthe presence ofpupal caps, larvae, and eggs. A 12 in grid divided into 1 in squares facilitated the count (MacDonald et al 1974). In some sections the cells were indi- vidually counted. The nest was sectioned in California to fit into the shippingcontainers,andwetriedtoreconstructcombplacementbefore the analysis began. Sections were numbered and flagged as they were unpacked to aid us in this endeavor. RESULTS The colony consisted of ca 84,000 workers, 32,000 males, and 232 queens (Table 1). The total numberofcells in the 22 comb layers ofthe Table 1. Numbers and typesofadultscollected with thecolony. Functional,developing, and nonfunctional queens(parens)add upto"Queens." AdultType ENTOMOLOGICALNEWS 126 nestwasca230,000,but 146,000ofthesecells were empty(Table 2). Dis- sectionsofthequeens revealed that 10 had fully functional ovaries that filledthegaster(eggsare 1.0-1.5mmwhenreadytolay).Twohadaslight development ofthe ovarioles but no eggs were >1 mm. All functional queenshadmultipleagespotsordarkdiscolorationsonthegaster(Ross 1984). The remaining 220 queens showed no ovarian development. DISCUSSION Althoughlarge,thiscolonywasprobablyenteringaperiodofdecline asevidencedbythegreatnumberofemptycells.Ten functional queens should have been able to lay eggs in many ofthese empty cells unless therewasconflictandfightingamongworkersand/orqueensinthenest. We could not determine any spheres ofinfluence foranyofthe queens because ofthe state ofthe nest when received. The large numberofmales in thecolonysuggests thatworkerswere laying eggs and producing at least some or perhaps most of these males. Questions asked ofneighbors suggested that this nestwas observed for30years. We have no evidence to support this claim and indeed, the nest analysis, including the construction of reproductive cells on the peripheryofsome combs, suggested that the nest was probably 2 years old, at most. Photoperiod is probablythe stimulus that allows newqueens tocir- cumvent reproductive diapause and to starteggdevelopment afterthey are inseminated (Spradbery 1973b, Ross and Matthews 1982). Queens frequentlyrejoin the parentcolonyifthe photoperiod is still increasing Table 2. Occupants ofcells from the 22 combs. Small, medium, and large larval counts (parens)add upto"Larvae." Vol. 104,No. 3,May&June, 1993 127 (upto21 June)inthatgeographical area,andifthewintertemperatures are mild.Theycan also rejoin thecolony as nondiapausing, functional queenswhenthedaylightisveryshortasthe"window"ofreceptiveness seemstobe 10-14hrs(Spradbery 1973b). Photoperiodslongerorshorter do not induce reproductive diapause, and the ovaries in these new queens are able to develop. ACKNOWLEDGMENTS WeareindebtedtoGeorgeBristol,Pescadero,andMarcMaas,Burlingame,forsending us thecolony. We are especially thankful to Robert Schoeppner, San Mateo Mosquito Abatement District,Burlingame,fordataon nestlocationand formanyphotographsof thenest,includingonethatappearsinthispaper,thataidedusinouranalysis.R.Zackand R. Schoeppnerreviewedthearticle. LITERATURECITED AkreR.D.,A.Greene,J.F.MacDonald,P.J.Landolt,andH.G.Davis. 1981.Yellow- Akrjea,ckeRt.sDo.f,AmaenrdicHa.NoCr.thReoefdM.ex1i9c8o1.. UASpDoAlyAggyrnioc.usHacnoldobnoyokof55V2e.sp1u0l2ap.pensylvanica (Saussure)(Hymenoptera: Vespidae). 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Wasps: anaccountofthebiologyandnatural historyofsolitary andsocial wasps. Univ.Washington Press,Seattle.408 p. Spradbery,J.P. 1973b.TheEuropeansocialwasp,Paravespulagermanica(F.)(Hymenop- tera:Vespidae)inTasmania,Australia. IUSSI Proc.VII Internal. Congr.pp. 375-380. Thomas,C. R. 1960.TheEuropeanwasp(Vespulagermanica Fab.)inNewZealand, inf. Ser. Dept. Sci. Ind. Res.NewZealand.27: 1-74. Tissot, A. N., and F. A. Robinson. 1954. Some unusual insect nests. Florida Ent. 37: 73-92. Vuillaume,M.,J.Schwander,andC.Roland. 1969.Notepreliminairesur1'existencede coloniesperennesetpolygynesdeParavespulagermanicaC. R.Acad. Sci. Ser. D.269: 2371-2372. BOOKS RECEIVED AND BRIEFLYNOTED BIOLOGYANDCONSERVATION OFTHE MONARCH BUTTER- FLY. S.B. Malcolm and M.P. Zalucki, eds. 1993. No. 38 Science Series, Natural History Museum ofLos Angeles County. 219 pp. 139 figs. 100 tables. Cloth. $90.00. This volume presents an interdisciplinary approach to understanding how Danaus plexippusfunctions,providing information foranobjectiveapproach toconservation of thespecies.Forty-fourpaperswrittenby50authorspresentadiversearrayofresearchon biologicalandconservationtopics.Thesepapersembracefourmainthemesofmonarch biology: communication and mating, host plant exploitation and chemical defense, migration,andoverwintering. THE SCIENCE OF ENTOMOLOGY. 3rd ed. W.S. Romoser and J.G. Wm. Stoffolano. 1994. C. Brown, Publ. 532 pp. Cloth. $60.90. The authors' stated objective for this third edition is to provide a broad, balanced introductorytexttothescienceofentomology,frombothbasicandappliedpointsofview, foruseinaone-quarterorone semestergeneralcourse.