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1、AfricanizedHoneyBeesintheAmericasWHATAREAFRICANIZEDHONEYBEES(AHB)?Africanizedhoneybees(alsoknownas"Africanizedbees"or"killerbees")aredescendantsofsouthernAfricanbeesimportedtoSouthAmericain1956.Brazilianscientistswereattemptingtobreedahoneybeebetteradapt
2、edtothetropics.Unfortunately,someofthebeesescapedquarantineandbeganbreedingwithlocalBrazilianhoneybees.Since1957,pureAfricanbeesandtheirhybridoffspring,theAfricanizedhoneybee,havevigorouslymultipliedandextendedtheirrangethroughoutSouth,Central,andNorthAm
3、ericaatratesfrequentlyexceeding200milesperyear.WhendidAfricanizedbeesfirstarriveintheUS?Whatareashavetheycolonized?Thefirstland-migratingswarmofAfricanizedbeeswasdetectedintheUSonOctober15,1990.ThesebeeswerecapturedinabaitedtrapatthebordertownofHidalgo,T
4、exas.AHBcolonieswerefirstreportedinArizonaandNewMexicoin1993andNevadain1998.ThefirstCaliforniadiscoverywasinOctoberof1994;oneyearlaterover8,000squaremilesofImperial,RiversideandnortheasternSanDiegocountiesweredeclaredofficiallycolonized.Todate,some140cou
5、ntiesinTexas,9countiesinNewMexico,all15countiesinArizona,3countiesinNevada,and9countiesinCaliforniahavereportedAfricanizedhoneybeefinds.ManyscientistsbelieveAfricanizedbeeswillcontinuetospreadandsuccessfullyoverwinterintheUS'ssoutherntierstates.WHATHAPPE
6、NSWHENAFRICANIZEDBEESENTERANEWTERRITORY?Thebeescontinuetopervadesuitablehabitatsbyswarming,theprocessbywhichcoloniesreplicate.Theoriginalqueenleavesthehivewithabouthalfthepopulationofthenesttobeginanewcolony.Anewqueenisrearedbytheremainingbeesintheorigin
7、alnest.Throughswarming,thepopulationdensity(#colonies/sq.mile)inanareaincreasesuntillimitedbynaturaldisasters(e.g.,fire)ordensity-dependentenvironmentalfactors,suchasfood,water,andcertaincommunicablediseases.Resourcecompetitionwithotherbeespeciesorcoloni
8、esmayalsolimitthenumberofnestsinagivenarea.WHEREDOAFRICANIZEDBEESNEST?Africanizedbeesarelessselectivethanournativebeeswhenchoosingnestingsites.Manynaturalandman-madeobjectshavebeencolonizedbyAHBswarmsinbothruralandurbanhab
