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Conflicts with Wildlife

Caroline Island reed warbler The brown tree snake is an opportunistic feeder and has caused the extirpation or extinction of most of Guam's native forest birds and lizards. The snake has eliminated 10 of the 13 native birds, many lizards species, and several bat species. As native bird populations decline, the snake population has shifted to feeding on abundant introduced lizards. Rodents, introduced birds, and bird eggs make up the rest of the snake's diet on Guam. In its native range, the snake population is kept in check through natural processes such as disease, competition for food, and predation. Although similar processes likely occur on Guam, they are not enough to control the brown tree snake population.


Species Historically Present on Guam


Wildlife Negatively Impacted by the Brown Tree Snake -
Photo Gallery
Species Historically Present on
Surrounding Islands
Guam Rail (Gallirallus owstoni) Micronesian Starling (Aplonis opaca)   Collared kingfisher (Todiramphus chloris) Gray white-eye (Zosterops cinereus)
Cardinal honeyeater (Myzomela cardinalis) Micronesian kingfisher (Todiramphus cinnamominus)   Caroline Island reed warbler (Acrocephalus syrinx)  
White terns (Gygis alba)        


Complementary Content