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NowoutoftheclearblueseasofftheislandsofPolynesiawherescientistshavediscoveredanareateemingwithsharks,normallythereisanaturallybalancewithlotsofpreyandfewerpredators,butnotsointhiscase.OursciencereporterJonathanWebtoldushowthisdiscoverycameabout.Well,actuallyscientistswenttothisatall.Anditisanusuallittleplace.Thereisachannelrunningthroughthemiddleofit,quiteasmallchannelonlyaboutthirtymetresdeep.Theywenttherebecauseadifferenttypeoffishnotsharksinfactbutagroupoffishareknowntospawnthere.Theywenttherethinkingtheyweregonnastudythosefish.Theyendedupfindingahugeconcentrationofgreyreefsharks,ahigherconcentrationtwoorthreetimeshigherthanit’sbeenfoundanywhereelseintheworld.Andsotheysaidabouttryingtounderstandwhatwasgoingon.Theytaggedsomeofthesharks.Theydidasortofcensusofthechannel.Becausethatabundanceof,sortofpeakpredatorifyoulike,somethingrightatthetopofthefoodchainisreallyhardtosustain.Normallyifyouaddupthebiomassinaparticularecosystem,there’llbemuchmuchmoreofthethingsdownthebottom,lotsandlotsofpreyandasyou’resayingnotverymanypredatorsso…Sowhydotheythinkthishappened?Yes,sotheytriedtoworkoutexactlywhatwasgoingonanditturnsoutthatthosespawningfish,theonesthattheywenttheretostudyinthefirstplacewereeffectivelygivingagreatbigdelivery.Everywintertimethosefishwould


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