Peoplebegantointroducenewplantsandanimalstotheislandsastheyarrived.Goats,pigs,dogs,andplantswerebroughttotheislandstomakelifeeasierforsettlers.Wecallthemintroducedspecies.Otherlivingthingsnotfromtheislands—rats,insects,andweeds—probablyarrivedon ships.
CatsarenotfromtheGalápagos.Acatcanharmnativeandendemic wildlife.
Wildboars,orwildpigs,nowroamthe islands.
MostGalápagosplantsandanimalsweren’texposedtothingsfromotherplaces.So,outsideorganismsputthematriskfordiseaseorevenattack.Wecallthese invasivespecies.Theycausedamagetotheislands.
Blackberryplantsgrowandspreadquickly.Theytakeupspacenativeplantsneedto grow.
PlantInvaders
About700oftheseinvasivespeciesareplants.Oneplant,thewildblackberry,hasbeenacauseforconcern.Itwasintroducedinthe1970s.Itquicklyspreadacrosstheislands.TheblackberriescrowdedouttheScalesia forestsonSantaCruzandthreeother islands.
Scalesiaplantsaregiantmembersofthedaisyfamily.Theycangrowupto15meters(49feet)tall.Theseforestsarehomestoavarietyofbirdspecies,includingthewoodpeckerfinch.Theberrieshavetakenoveralotof land.
Farmersconsidertheblackberryaweed.Itturnsfarmsintowastelandsbychokingoutotherplants.Fightingblackberriesishardwork.Destroyingitbyhandcanbeback‑breaking.Andkillingitwithherbicidesistoorisky.Thepoisonscouldharmother plants.
