Weather and regional crop composition variation drive

EcologicalEntomology(2020),45,573–582DOI:10.1111/een.12830WeatherandregionalcropcompositionvariationdrivespatialsynchronyoflepidopteranagriculturalpestsJONATHANA.WALTER,1,2LAWRENCEW.SHEPPARD,3P.DILIPVENUGOPAL,4DANIELC.REUMAN,3GALENDIVELY,4JOHNF.TOOKER5andDEREKM.JOHNSON11DepartmentofBiology,VirginiaCommonwealthUniversity,Richmond,Virginia,U.S.A.,2DepartmentofEnvironmentalSciences,UniversityofVirginia,Charlottesville,Virginia,U.S.A.,3DepartmentofEcologyandEvolutionaryBiologyandKansasBiologicalSurvey,UniversityofKansas,Lawrence,Kansas,U.S.A.,4DepartmentofEntomology,UniversityofMaryland,CollegePark,Maryland,U.S.A.and5DepartmentofEntomology,ThePennsylvaniaStateUniversity,UniversityPark,Pennsylvania,U.S.A.Abstract.1.Spatialsynchrony,thetendencyfortemporalpopulationfluctuationstobecorrelatedacrossmultiplelocationsatregionalscales,iscommonandcontributestotheseverityofoutbreaksandepidemics,butislittlestudiedinagriculturalpests.2.Thisstudyanalysedspatialsynchronyfrom1974to2008in16lepidopteranagriculturalpestsinMaryland,U.S.A.,andinvestigatedwhetherpestsynchronyisdrivenbyinterannualvariabilityinseasonalweatherandtheareasplantedindifferentcroptypes.3.Lepidopteranpestsexhibitedhighdegreesofspatialsynchrony,whichwasdrivenbyenvironmentalvariation,aphenomenonknownastheMoraneffect.Region-widevariationintheareasplantedinmajorcropsdrovespatiallysynchronousabundancefluctuationsinmorethanhalfofstudiedspecies.Thecombinationofweatherandcropcompositionexplainedlargefractionsofsynchronyinblackcutwor