Featured Species

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.

A black and brown tropical bat climbing through brush

The Mariana fruit bat is a medium-sized fruit bat in the family Pteropididae that weighs 0.66 to 1.15 pounds (330 to 577 grams) and has a forearm length ranging from 5.3 to 6.1 in (13.4 to 15.6 cm); males are slightly larger than females. The underside (abdomen) is colored black to brown, with...

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Cycas micronesica, a member of the Cycadaceae family, is a gymnosperm, usually an unbranched tree with a thick trunk. Adult stem range between 8 to 12 m (26 to 39 ft) in length and 14 to 25 cm (5.5 to 49 in) in diameter. Leaves are glossy, pinnate (leaflets are attached along an extension of the...
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A small black crow with a slight greenish black gloss on the head; back, wings and tail with bluish-black gloss; underparts with dull greenish-black gloss; bases of feathers light grayish, more nearly white on neck producing a somewhat ragged appearance; nasal bristles short but extending over...
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Close-up photo of Serianthes nelsonii

Serianthes nelsonii is a tree in the Fabaceae (pea) family, to 20 to 36 m (66 to 118 ft) with a trunk to 2 m (6.6 ft) in diameter. Spreading-ascending branches with a moderately broad crown. The leaves are twice-pinnate, with 10 to 20 pairs of pinnae, each of which has 22 to 30 pairs of leaflets...

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A green sea turtle swims along the bottom of the reef.

The green sea turtle grows to a maximum size of about 4 feet and a weight of 440 pounds. It has a heart-shaped shell, small head, and single-clawed flippers. Color is variable. Hatchlings generally have a black carapace, white plastron, and white margins on the shell and limbs. The adult...

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