DL forecast

SeasonalforecastforDesertLocustwinter/springbreeding(December2015–May2016)
K.Cressman,SeniorLocustForecastingOfficer,FAODLIS
WesternRegion(CLCPRO)
Mauritania.GoodrainsfellduringAugustinthewest(Moudjeria-Akjoujt-AguilalFaye)followedbyunusually
heavyandwidespreadrainsinthenorthwestandnorthinSeptemberandOctober,whicharelikelytoallow
breedingconditionstoremainfavourableinsomeareasforuptosixmonths.Egg-layingcommencedinthe
westshortlyaftermid-September,andhoppersformedgroupsinlateOctoberandstartedfledginginearly
November.Thecurrentseasonalprecipitationoutlooksuggestsdrierthannormalconditionsduringthewinter
andspringexceptforabove-averagerainsinInchiriduringFebruary.Giventherainfallthathasoccurredand
theexpectedwarmerthannormalwintertemperatures,thereisapossibilityforthreegenerationsofbreeding
thisyearinthenorthwestandnorth(Sep-Dec,Dec-Feb,Mar-Apr)thatcouldcauselocustnumberstoincrease
considerably,givingrisetohopperbandsandswarms.
Morocco.UnusuallyheavyandwidespreadrainsfellintheWesternSaharainSeptemberandOctober,which
arelikelytoallowbreedingconditionstoremainfavourableinsomeareasforuptosixmonths.Thecurrent
seasonalprecipitationoutlooksuggeststhataveragetodrierthannormalconditionsarelikelyduringthe
winterandspringexceptforabove-averagerainsinsouthernandcentralareasduringFebruary.Giventhe
heavyOctoberrainsandwarmerthannormaltemperaturesexpected,thereisapossibilityforatleasttwo
generationsofbreedingbetweenDecemberandMaythatcouldcauselocustnumberstoincrease
substantially,givingrisetohopperbandsandswarms.
Algeria.UnusuallyheavyandwidespreadrainsfellinthewestbetweenTindoufandBeniAbbesinlateOctober
thatmayallowbreedingconditionstoremainfavourableinsomeareasforupto4-6months.Thecurrent
seasonalprecipitationoutlooksuggeststhatdrierandwarmerthannormalconditionsarelikelyduringthe
winterandspringexpectforabove-averagerainsinsouthernandcentralareasduringFebruary.Consequently,
theremaybeapossibilityforuptwogenerationsofbreedingbetweenDecemberandMaythatcouldcause
locustnumberstoincreasesubstantially,givingrisetohopperbandsandswarms.
Libya.GoodrainsfellinlateSeptemberbetweenGhatandAlHamadaAlHamra.Limitedareasofgreen
vegetationdevelopedbyearlyNovember.Asthecurrentseasonalprecipitationoutlookisforbelow-average
winterrainfall,onlysmall-scalebreedingmayoccurandlocustnumbersarelikelytoremainlow.
EstimatedrainfallinNWAfricaduringSeptemberandOctober2015(source:IRI)
FirstlayingandfledgingdatesofthreepotentialgenerationsoflocustbreedinginMauritania,September2015toMay2016
FAODLISSeasonalForecast
25Nov2015
CentralRegion(CRC)
Sudan.GoodrainsfirstfellinW.Oko/Diibofthenortheastinmid-Septemberfollowedbyheavierrainsinearly
OctoberinallcoastalandsubcoastalareasandinlateOctoberprimarilyinnorthernandcentralareas.Byearly
November,greenannualvegetationbegantoemergeinW.Oko/Diib,incentralareasoftheRedSeaHills,
TokarDeltaandonthesouthernplains.Breedingislikelytocommencefirstinthenortheast.Iffirstgeneration
egg-layingoccursbeforemid-December,therewouldbesufficienttimefortwogenerationsofbreeding,
especiallyifthecurrentseasonalprecipitationoutlookforabove-averagerainsinFebruaryremainsconsistent.
Ifthisoccurs,thengregarizationmaytakeplaceinaboutAprilwhenvegetationdriesout;otherwise,asingle
generationofbreedingwillkeeplocustnumberslow.
Eritrea.GoodrainsfellalongtheentirecoastinlateAugustandcontinuedonthesoutherncoastinSeptember.
RainfalloccurredinearlyOctoberandagaininearlyNovembernearSheibandMehimet.ByearlyNovember,
greenvegetationwaspresentnearSheib.Thecurrentseasonalprecipitationoutlooksuggestsabove-average
rainsinJanuaryandFebruarythatcouldallowfavourableconditionsfortwogenerationsofbreedingifinitial
egg-layingoccursbeforemid-December.Otherwise,onegenerationofbreedingwillkeeplocustnumberslow.
Egypt.LightrainsfellnearAbraqinmid-OctoberandnearHalaibattheendofOctober.Small-scalebreeding
mayoccurfromNovemberonwardsnearAbraqwheregreenannualvegetationbegantoemergeinearly
November.However,asecologicalconditionsareprimarilydryandwinterrainsarepredictedtobeonly
averageorbelow-average,locustnumbersareexpectedtoremainlow.
SaudiArabia.HeavyrainsfellonthecoastbetweenLithandJizaninlateAugustandcontinuedinsomeplaces
duringSeptember.GoodrainsfellinmidOctoberbetweenQunfidahandJizanwhileheavierrainsfellnear
UmmLajjattheendofthemonth.VegetationbegangreeningupinOctobernearJizan.Twogenerationsof
breedingcouldoccur,especiallynearJizan,ifinitialegg-layingtakesplacebytheendofDecemberandthe
currentprecipitationoutlookforabove-averagerainsinJanuaryandFebruaryremainsconsistent.
Yemen.HeavyrainsfellontheRedSeacoastduringAugustandSeptemberfollowedbygoodrainsinthefirst
halfofOctober.AsvegetationbecamegreeninOctoberandthecurrentprecipitationoutlookindicatesaboveaveragerainsfromDecembertoFebruary,itislikelythattwogenerationsofbreedingwilltakeplacebetween
nowandApril.Thereafter,gregarizationcouldoccurasvegetationdriesout.Asheavyrainsassociatedwith
cyclonesChapalaandMeghfellinearlyNovemberandthecurrentprecipitationoutlooksuggestsaboveaveragerainsforJanuary,FebruaryandMay,twogenerationsofbreedingcouldoccurontheGulfofAden
coastifinitialegg-layingtakesplacebeforemid-December.BreedingintheinteriorareasofShabwahand
HadhramautcouldoccurfromaboutMarchonwardsoncetemperatureswarmup.
Ethiopia.ThesituationdependsonthescaleandtimingofwinterbreedinginnorthwestSomalia.Giventhe
goodrainsthatfellthereinearlyNovemberandthatthisisanElNiñoyear,lowtomoderatenumbersofadults
andperhapsafewsmallgroupscouldarrivebetweenJijigaandAyashabetweenMarchandMay.
Djibouti.ThesituationdependsonthescaleandtimingofwinterbreedinginnorthwestSomalia.Giventhe
goodrainsthatfellthereinearlyNovemberandthatthisisanElNiñoyear,lowtomoderatenumbersofadults
andperhapsafewsmallgroupscouldarriveintheeastbetweenMarchandApril.
Somalia.Vegetationisexpectedtobecomegreenshortlyonthenorthwestcoastfromgoodrainsassociated
withcycloneMeghthatfellinearlyNovember.Above-averagerainsareexpecteduntilMarchasaresultofEl
Niño.Ifinitialegg-layingoccursbeforemid-December,thereissufficienttimefortwogenerationsofbreeding;
otherwise,onlyonegenerationofbreedingwilltakeplace,keepinglocustnumberslow.Breedingcouldextend
tocoastalandsubcoastalareasnearBosasowhereheavyrainsfellfromMegh.Anincreasingnumberoflocusts
mayappearontheplateaufromaboutMarchonwards.
FAODLISSeasonalForecast
25Nov2015
EstimatedrainfallinwinterbreedingareasoftheCentralRegion,1September–10November2015(source:IRI)
Precipitationoutlookin2016forJanuary(left)andFebruary(right),issuedNovember2015,indicatesabove-averagerainfall
of20-60%inthewinterbreedingareasalongthesouthernRedSeaandGulfofAdencoasts(source:WCS)
Nov2015–May2016:twopotentialgenerationsoflocustbreedingintheCentralRegion
FAODLISSeasonalForecast
25Nov2015
EasternRegion(SWAC)
Iran/Pakistan.Theseasonalprecipitationoutlookindicatesslightlyabove-averagerainsduringFebruaryin
southeastIranandsouthwestPakistan.Coupledwithwarmerthanusualtemperatures,thereispotentialfora
singlegenerationofspringbreedingtocommencesomewhatearlierthannormalintheseareas.Ifso,thescale
ofinitialbreedingwillbeextremelylowduetothecurrentabsenceoflocustsintheregion.Furthermore,
below-averagerainspredictedforAprilmaylimitspringbreedingandkeepDesertLocustnumberslowinthe
breedingareas.Nosignificantdevelopmentsareexpected.
SeasonalprecipitationoutlookforFebruary2016,issuedNovember2015,indicatesabove-averagerainfallof20-60%inthe
springbreedingareasofsoutheastIranandsouthwestPakistan(redbox)(source:IRI)
Giventheuncertaintyofrainfallandcurrentabsenceoflocusts,severalsingle-generationbreedingscenariosforspring
2016insoutheastIranandsouthwestPakistanareestimatedforearly(1February)andlateegg-laying(1April)
FAODLISSeasonalForecast
25Nov2015