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TheBiggestThreatstoEndangeredDolphinSpecies

TheSocietyofMarineMammalogyrecognizes41distinctdolphinspecies,nineofwhichareconsideredendangeredbyeithertheIUCN,theEndangeredSpeciesAct(ESA),orboth,andonethatmayalreadybeextinct.TheIUCNconsiderstheYangtzeriverdolphin,theAtlantichumpbackdolphin,theSouthAsianriverdolphin,theAmazonriverdolphin,theIrrawaddydolphin,theIndianOceanhumpbackdolphin,andHector’sdolphintobeendangered,whiletheESAalsoincludesthekillerwhaleandthefalsekillerwhale.Inaddition,allendangereddolphinpopulationsareeitherunknownorbelievedtobedecreasing.

Avastmajorityofthesespeciesareoceanic,whilejustfourareconsideredriverdolphins.Asisthecasewithallmarinemammals,dolphinsarealsoprotectedbytheMarineMammalProtectionAct,whichkeepsthemsafefrombeinghunted,captured,orkilledinU.S.waters.

CriticallyEndangeredSpecies

Twospecies,theYangtzeriverdolphinandtheAtlantichumpbackdolphin,arecriticallyendangered,withthelattermakingadramaticjumpfrom“vulnerable”to“criticallyendangered”ontheIUCNRedListofEndangeredSpeciesin.

3IUCNattributedthisrapiddeclinetolowreproductivecapabilityandthreatsfromfishingindustrybycatch,predictingan80%populationreductionoverthenextthreegenerations.Today,thereareanestimated1,Atlantichumpbackdolphinsleftinthewild.

Thoughuniversallybelievedtobeoneofthemostendangeredcetaceansontheplanet,manyscientistsmaintainthattheYangtzeriverdolphin,alsoknownasthebaiji,becameextinctin.Until,thiselusivefreshwaterdolphin’sstatushadn’tbeeninvestigatedsincethepopulationnumbered13individualsinthes.In,anintensivesix-weeksurveyfoundzeroevidenceofthespecies’survival,whichresearcherslinkedtoa



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