The Brown Treesnake, Colubridae Boiga irregularis
Shot this one in one of the GIAA traps along the perimeter fenceline.
The brown Treesnake is a member of the Family Colubridae, a diverse assemblage of primarily harmless snakes, and is native to coastal Australia, Papua New Guinea, and a large number of islands in northwestern Melanesia. The species occurs on both large and small islands, extending from Sulawesi in eastern Indonesia through Papua New Guinea and the Solomon Islands and into the wettest coastal areas of Northern Australia. Individuals of this species have been discovered on several extralimital islands, but the snakes on Guam represent the only documented reproductive population outside the native range.