28 November 2007

Breeding Rails

Guam Rail (Gallirallus owstoni), Extinct in the Wild

Guam is a tiny island territory, comprising a mere 541 square kilometers, or a little more than half the size of New York City. Until the 1980s, this little island paradise was home to the Guam Rail, which existed only on this tiny patch of land. In 1980 The Guam Rail disappeared from its natural home.

What happened? It all goes back to World War II, when foreign ships accidentally imported the Brown Tree Snake. The ground-dwelling Guam Rails had never had to deal with predators such as snakes before, and were completely defenseless. The snakes decimated not only the Rails, but also 9 other native species, 5 of which were found nowhere else in the world.

The Guam Rail is not extinct yet, however, as it is still held in captivity in Guam and American zoos, and has been bred successfully. Although reintroduction efforts are underway on the nearby island of Rota, their success is far from guaranteed, as the Brown Tree Snake persists and continues to threaten introduced birds. Researchers have had some success in keeping snakes out of small controlled areas, but as long as the snakes pose a threat, this species will require monitoring and management.

Recently, the National Aviary in Pittsburgh, one of the few zoos working to breed the birds, shipped off another year-and-a-half old Rail to join its struggling fellows back in the wild. Godspeed and goodluck!

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