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Musselscancleanupupto38litersofriverwatereachday,removingalgae,metalsandothermaterials.Theprocesscancreateabetterriverenvironmentforfish,amphibians,plantsandinsects.Forthisreason,scientistsareworkingtofindthecauseofthelargedropinmusselpopulations.JordanRichardisabiologistwiththeU.S.FishandWildlifeService.HetoldTheAssociatedPressthatofficialshaveestimatedthathundredsofthousands,possiblyevenmillions,ofmusselshavediedintheClinchRiver.Themassdie-offintheriverofonekindofmussel,calledthepheasantshell,hasbeenespeciallyworrisome.Officialssaythepopulationofpheasantshellsdroppedfrom94,000in2016tolessthan14,000in2019.Theymeasuredthedecreasealonga200-meterstretchoftheClinchRiver.Similardie-offshavebeenreportedonatleastfiveU.S.riversandanotherinSpain.Richardhasstudiedreportsofsimilardie-offsovertheyearsinriversaroundtheworld.Butsofarhehasnotcomeupwithmanyanswersaboutwhytheyhappened.SpeakingabouttheClinch,RichardsaidtherivercouldevenbecomparedtotheAmazonbecauseitcontainssomanydifferentkindsoflife.HespoketotheAPwhileexaminingtheriver'smusselpopulationinaruralcommunityinTennessee.Musselpopulationsaroundtheworldhavedroppedsharplyoverthepast100years.Scientistsblamethisonpollution,habitatlossandclimatechange.Buttheysuspectthemostrecentdecreaseshaveanothercause.Richardandhisteambelieveaninfectiousdiseasecouldberesponsible.Theteamiscomparinghealthypheasantshellmusselstodyingonesinanattempttonarrowdownalistofpossiblediseases."Alllivingthingsarechock-fullofmicroorganisms,andwedon'thaveanysortofmapforwhatishealthyinsideamussel,"Richardsaid.UniversityofWisconsindiseasespecialistTonyGoldbergishelpingwiththeinvestigation.Hespecializesinwildlifeillnessesofunknowncause.GoldbergtoldtheAPthatoftendiseaseisthefinalthingtokillaspeciesthathasalreadybeenharmedbyotherenvironmentalconditions.However,hesaysheishopefulthatthefreshwatermusselteamwillbeabletodiscoverthecauseofthemassivedie-offsandfindawaytopreventthem.TheteamincludesscientistsfromtheU.S.GeologicalSurveyandanonprofitconservationgroup."Iseeitasaraceagainsttime,notanimpossibletask,"Goldbergsaid,adding"...ifwelosethesemussels,theriverswealllovearenevergoingtobethesame."I'mBryanLynn.TheAssociatedPressreportedonthisstory.During2019,wecoveredsomebigdevelopmentsinvolvingcomputeranddevicetechnology.WealsoreportedongrowingoppositiontofacialrecognitionsystemsandwarningsbytheinventoroftheWorldWideWebabouttheinternet'sfuture.Googleannouncedithadcompletedsuccessfulexperimentsthatledtoamajordevelopmentinquantumcomputingtechnology.Inonetest,theteamsaiditsquantumcomputerprocessorwasabletocompleteacomplexmathematicalprobleminjust200seconds.

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