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1、MarketSoughtForGreenCrab ByJonathanLevittELLSWORTH—EuropeangreencrabshavebeenwreakinghavoconMaine’sshellfishindustrysincetheearly1930s.Remarkably,inanerawhenMainefishermensellanythingfromseaurchinstoworms,nomarkethasbeendevelopedfortheinvasivepests.“Theygrowquickly.Theyhav
2、eanespeciallybroadhabitat,temperatureandsalinitytolerancethatallowsforabroadgeographicdistribution.Allofthismakesforagreatinvasivespecies,andnothinghasevolvedtohandlethem.”—Prof.BrianBealGreencrabWASHINGTONDEPT.OFFISH&WILDLIFEBecauseoftheirsmallsize(alargegreencrabwouldmea
3、sure fewerthanthreeinchesacross),pickinggreencrabmeat(justasdeliciousasrockorJonahcrab)isatediousandprohibitivelyexpensiveprocess,afactthathaslimitedanycommercialharvest.Withoutnaturalpredatorsorafisherytocontroltheirnumbers,greencrabswillcontinuetoout-competenativespecies
4、andtakeaserioustollonshellfishpopulations.“Wickedwintersandacommercialgreencrabfisheryaretheonlythingsthatwecanhopefor,”saidBrianBeal,professorofmarinebiologyattheUniversityofMaineMachias.Sincetheirarrivalintheballastwateroftrans-Atlanticships,theinvasivegreencrabshavepush
5、ednativespeciestodeeperwatersandarenowthedominantpredatorinMaine’sinter-tidalzone.NativetotheBritishIsles,greencrabswerefirstspottedonAmericanshoresintheLongIslandSoundaround1800.Sincethen,thevoraciousfeedershavebeenfeastingtheirwaynorthalongthecoast,decimatingpopulationso
6、fclams,scallopsandlobster.AccordingtoBeal,thegreencrabisa “veryfeistyorganism.”“Theygrowquicklyandreproducequickly,”hesaid.“Theyhaveanespeciallybroadhabitat,temperatureandsalinitytolerancethatallowsforabroadgeographicdistribution.Allofthismakesforagreatinvasivespecies,andn
7、othinghasevolvedtohandlethem.”WorkingwiththeBealsIslandRegionalShellfishHatchery,marinebiologistBillWaltonreceiveda$10,000grantfromtheMaineTechnologyInstitutetostudythefeasibilityofacommercialfisheryforthegreencrab.ThehopewastodevelopafisherysimilartowhatexistsintheChesape
8、akeBaywithsoft-shelledbluecrabs.Thetrickwouldbetodiscoverawaytocatchthecrabsduringthethre
