Animalia > Chordata > Aves > Gruiformes > Rallidae > Gallirallus > Gallirallus owstoni

Gallirallus owstoni (Guam Rail)

Synonyms: Rallus owstoni

Wikipedia Abstract

The Guam rail (Gallirallus owstoni) (Chamorro name: ko'ko' ) is a flightless bird, endemic to the United States territory of Guam. The Guam rail disappeared from southern Guam in the early 1970s and was extirpated from the entire island by the late 1980s. This species is now being bred in captivity by the Division of Aquatic and Wildlife Resources on Guam and at some mainland U.S. zoos.
View Wikipedia Record: Gallirallus owstoni

Endangered Species

Status: Extinct in the wild
View IUCN Record: Gallirallus owstoni

EDGE Analysis

Uniqueness Scale: Similiar (0) 
 Unique (100)
Uniqueness & Vulnerability Scale: Similiar & Secure (0) 
 Unique & Vulnerable (100)
ED Score: 4.93445
EDGE Score: 4.55336


Adult Weight [1]  226 grams
Female Weight [1]  212 grams
Male Weight [1]  241 grams
Weight Dimorphism [1]  13.7 %
Diet [2]  Carnivore (Invertebrates), Carnivore (Vertebrates), Piscivore, Frugivore, Herbivore
Diet - Ectothermic [2]  10 %
Diet - Fish [2]  10 %
Diet - Fruit [2]  20 %
Diet - Invertibrates [2]  30 %
Diet - Plants [2]  20 %
Diet - Scavenger [2]  10 %
Forages - Understory [2]  30 %
Forages - Ground [2]  60 %
Forages - Water Surface [2]  10 %
Incubation [3]  19 days


Name Countries Ecozone Biome Species Report Climate Land
Marianas tropical dry forests Micronesia Oceania Tropical and Subtropical Dry Broadleaf Forests    

Biodiversity Hotspots

Name Location Endemic Species Website
Polynesia-Micronesia Fiji, Micronesia, Polynesia, Samoa, Tonga, United States Yes

Emblem of


Institutions (Zoos, etc.)

Institution Infraspecies / Breed 
Cincinnati Zoo & Botanical Garden
Fresno Chaffee Zoo
Lincoln Park Zoological Gardens
Louisville Zoological Garden
National Aviary in Pittsburgh
Oklahoma City Zoological Park
Racine Zoological Gardens
San Antonio Zoological Gardens & Aquar
San Diego Wild Animal Park
San Diego Zoo
Santa Fe CollegeTeaching Zoo
Sedgwick County Zoo
Smithsonian Conservation Biology Institute in Front Royal
Smithsonian National Zoological Park
The Philadelphia Zoo





Attributes / relations provided by
1Jenkins, JM (1979) Natural history of the Guam Rail. Condor 81: 404-408
2Hamish Wilman, Jonathan Belmaker, Jennifer Simpson, Carolina de la Rosa, Marcelo M. Rivadeneira, and Walter Jetz. 2014. EltonTraits 1.0: Species-level foraging attributes of the world's birds and mammals. Ecology 95:2027
3del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
Ecoregions provided by World Wide Fund For Nature (WWF). WildFinder: Online database of species distributions, ver. 01.06 WWF WildFINDER
Biodiversity Hotspots provided by Critical Ecosystem Partnership Fund
Images provided by Google Image Search
Abstract provided by DBpedia licensed under a Creative Commons License
Weather provided by NOAA METAR Data Access