Wildlife & Habitat

Micronesian kingfisher

After World War II, the brown tree snake was accidentally introduced into Guam. With no natural predators and abundant prey, the snake population steadily grew and spread throughout the island. As the snakes dispersed, forest bird and fruit bat populations plummeted. By the late 1980s, 12 species of birds and the little Mariana fruit bat had disappeared from Guam. The Refuge provides habitat for the last remaining populations of the endangered Mariana fruit bat, Mariana crow, and the Serianthes nelsonii tree. The brown tree snake is considered the primary cause for the decline of native Guam bird species.

  • Birds

    Mariana Crow

    Aga, also known as the Mariana Crow or Corvus kubaryi, is a small black crow. The only corvid in Micronesia, this endangered bird is endemic to Guam and Rota.

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  • Mammals

    Mariana Bat

    Fanihi, also known as the Mariana Fruit Bat or Pteropus mariannus, is a medium-sized bat measuring 195 to 250 mm from head to rump, with a wingspan of 860 to 1065 mm. The males are slightly larger than the females. The abdomen and wings are dark brown to black with individual gray hairs intermixed throughout the fur. The mantle and sides of the neck are bright gold on most animals but in some individuals, this region may be pale gold or pale brown. The color of the head varies from brown to dark brown.

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  • Reptiles & Amphibians

    Green turtle

    Haggan betde, also known as green sea turtles or Chelonia mydas, are an endangered species of sea turtle characterized by a smooth carapace with four pairs of lateral scutes and a coarsely serrated lower jaw-edge. Haggan cari, also known as the Hawksbill sea turtle or Eretmochelys imbricata, is a critically endangered species, named for its narrow head and sharp, bird-like beak that can reach into cracks and crevices of coral reefs when foraging.

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  • Insects

    Mesb Adult

    Ababang, also known as the Mariana eight spot butterfly or Hypolimnas octocula marianensis, is endemic to Guam and has only been recorded on the islands of Guam and Saipan. Because of its rarity and limited distribution, this subspecies became listed as endangered under the Endangered Species Act in 2015. 

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  • Habitat

    Serianthes leaf

    Hayun lagu, or Serianthes nelsonii is one of the largest native trees in the Mariana Islands. An endemic tree found only on the islands of Guam and Rota, Hayun lagu is an endangered species with only one adult tree known living on Guam. For its protection, the tree was listed as an endangered species in 1987. In addition to juvenile Hayun lagu, various other native and endemic plant species can also be found throughout the refuge.

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