Guam Rail

Guamralle ( Gallirallus owstoni )

The Guamralle ( Gallirallus owstoni ) is a Rail bird that can fly more than 1 to 2 meters. 6 7

Appearance

Adults weigh about 200 g back, neck, trunk, tail, legs and beak are dark brown. On the wing, on the lower part of the chest, abdomen and under tail there is a pattern of black and white feathers. On the neck, on the upper chest and the eyes are gray spots. The body is like other Rails elongated and laterally compressed, so that the animals can move quickly through dense vegetation. Juveniles have a black Dunengefieder for the first three weeks. You can reach eight weeks their full weight and can be over 11 years old. 6 7

Way of life

The Guamralle is endemic to Guam and was originally represented in most habitats on the island, such as forest, savannah, scrubland, secondary grasslands, Farndickichte, agricultural areas. She considers herself mainly in places, where there are both shrubs and grass. Within forests or wetlands, they are rarely seen. 6 8

The Guamralle eats animal rather than vegetable feed. These include snails, carrion, geckos, insects. The imported African Large agate snail ( Achatina fulica ) forms an important part of the diet. In plants, they also eat seeds, palm fronds but various vegetables and fruits. 6

They picked their food mostly from the ground, especially snails. It also captures low-flying insects, especially butterflies, with the beak from the air. By stretch, they can reach food that is 40cm or more above the ground. Pieces of snail shells and coral fragments are recorded to aid digestion. 6 8

Reproduction

Prisoners of animals bred for the first time at the age of five months. They breed throughout the year distributed, often especially during the rainy season in July and November. It is believed that they nest per year multiple times is unknown. 6 8

In a nest with 13 cm diameter, which is built by both parents, the female lays 3-4 eggs of 3 × 4cm size. As with many animals on earlier predator -free islands, the clutch is smaller than clutches of their relatives from the mainland. Both parents incubate alternately for about 20 days. The chicks hatch simultaneously. A parent animal eats the eggshells. 6

The 1-4, average but 2 young are precocial and leave with the parents within 24 hours of the nest. Chicks are made by the parent animals sometimes on the food carefully and pick it then on their own, but sometimes also fed with trapped flying insects. 6

Threat Status

The Rail was formerly widely used in Guam and was hunted by the inhabitants of the island. 1960, the trade in young birds and eggs and the hunting was prohibited on the birds. 1964-1976 was allowing limited hunting. She died on the southern part of the island beginning of the 70s, but there is no indication that this might be responsible at the time already banned hunting. 1981 about 2300 birds were only found in the north of the island. In 1983 there were only two small, non-contiguous populations. Cause of the extinction were introduced predators, especially the brown tree snake ( Boiga irregularis ) and car accidents. 4 5 7

In captivity, the Rail was bred very successfully since 1984 and since 1995, more than 100 of them released back into the wild. After the success were slim at first, the night tree snakes were killed by traps and kept away from the habitat of the birds. Since then, breeding success has been reported. 1 2 3 4 5 7

In addition, an attempt was made to locate the Rail since 1987 on the nearby island of Rota. The first successful broods were reported in 1999 there. 8

Swell

  • 1 Delany, S. and S. Scott. , 2002. Waterbird Population Estimates? Third Edition. Wetlands International Global Series No.. 12, Wageningen, The Netherlands. Pp: 115
  • 2 Taylor, Barry. In 1998. Guam Rail. In Rails: A guide to the Rails, crakes, gallinules and Coots of the World. Yale University Press. Pp: 258,259th
  • 3 Fritts, T. H., and D. Leasman -Tanner. 2001 The Brown Treesnake on Guam. How the arrival of one invasive species damaged the ecology, commerce, electrical systems, and human health on Guam: A comprehensive information source. (World Wide Web page ). Available: http://www.fort.usgs.gov/resources/education/bts/bts_home.asp (Dec. 1, 2005)
  • 4 Julie A. Savidge: Extinction of an Iceland Forest Avifauna by Introduced at Snake. Ecology, Vol 68, No. 3 (Jun., 1987), pp. 660-668. doi: 10.2307/1938471
  • 5 Thomas H. Fritts, Gordon H. Rodda: The Role of Introduced Species in the degradation of Iceland Ecosystems: A Case History of Guam. Annual Review of Ecology and Systematics, Vol 29, 1998 ( 1998), pp. 113-140
  • 6 J. Mark Jenkins: Natural History of the Guam Rail. The Condor, Vol 81, No. 4 (Nov., 1979), pp. 404-408. doi: 10.2307/1366967
  • 7 Robert E. Beck, Jr. and Julie A. Savidge: NATIVE FOREST BIRDS OF GUAM AND ROTA OF THE COMMONWEALTH OF THE MARIANA ISLANDS NORTHER1 ~ RECOVERY PLAN. Division of Aquatic and Wildlife Resources Department of Agriculture Government of Guam Agana, Guam
  • 8 Gallirallus owstoni in the Red List of Threatened Species IUCN 2011 Posted by: . BirdLife International, 2010 Retrieved on November 13, 2011.
Genus Walter Rothschild, 2nd Baron Rothschild
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