【FencingorNotWildlifefencesareconstructedforavarietyofreasonsincludingtopreventthespreadofdiseasestoprotectwildlifefrompoachers(偷猎者)andtohelpmanagesmallpopulationsofthreatenedspecies.Human-wildlifecon】

　　FencingorNot

　　Wildlifefencesareconstructedforavarietyofreasonsincludingtopreventthespreadofdiseasestoprotectwildlifefrompoachers(偷猎者)andtohelpmanagesmallpopulationsofthreatenedspecies.Human-wildlifeconflictisanothercommonreasonforbuildingfences.Wildlifecandamagevaluablefarmanimalsandcrops.Somespeciescarrydiseasesofagriculturalconcernandafewthreatenhumanlives.Atthesametimepeoplekillwildanimalsforfoodtradeortodefendlivesorpropertyandhumanactivitiesdestroywildlifehabitat(栖息地).Separatingpeopleandwildlifebyfencingcanappeartobeamutuallybeneficialwaytoavoidsuchharmfuleffects.ButinapaperinthejournalSciencepublishedrecentlysomescientistsarguethatfencingshouldonlybeusedifworsecomestoworst.

　　Accordingtothescientistsalthoughfencingcanhaveconservationbenefitsitalsohascosts.Whenareasofwildlifehabitatarechangedintoislandstheresultingsmallandisolatedpopulationstendtowardsextinctionandtheresultinglossoflarger-bodiedspeciescanaffectinteractionsbetweenspeciesinwaysthatcausefurtherlocalextinctions.Thereforescientistsareaskingthatconservationistscarefullyweighupthebiodiversitycostsandbenefitsofnewandexistingfences.

　　Inadditiontofences’ecosystem-wideimpactthescientistsdon’tthinktheyalwaysachievetheirspecificaims.Constructionoffencestoreducehuman-wildlifeconflicthasbeensuccessfulinsomeplacesbutthechallengesofappropriatefencedesignlocationconstructionandprotectionmeanthatfencesoftenfailtodelivertheanticipatedbenefits.Insomeplacesfencesalsoprovidepoacherswithareadysupplyofwireformakingtraps.

　　Avarietyofalternativeapproachesincludingbettercaringforfarmanimalscommunity-basedcrop-guardinginsuranceandwildlife-sensitiveland-useplanningaresuggestedtoreduceconflictsbetweenpeopleandwildlifewithouttheneedforfencing.SomeprojectsworkingwithlocalpeopleandgovernmentagenciesinIndonesiahaveshownthathuman-elephantconflictcanbedramaticallyreducedwithoutusingfences.

　　Thescientistsconcludethatasclimatechangeincreasestheimportanceoffacilitatingwildlifemobilityandcon