Abstract
The ecosystem of Uotsuri-jima, one of the islands in the Senkaku Archipelago, off southwestern Japan, has probably been devastated by a dramatic increase in goats (Capra aegarus) since their deliberate introduction in 1978. Because the Senkaku Islands are claimed as national territory by China, Taiwan, and Japan, scientific researchers have been unable to land on Uotsuri-jima, nor have there been opportunities to eradicate the goats there. The effects of the goats on the vegetation of the island were assessed therefore using remote-sensing techniques: aerial photographs, Landsat satellite images, and an IKONOS satellite image. The results showed that bare patches have emerged in several areas, and that particular floral communities on the raised coral reefs may have already been lost. Since the flora of the sub-canopy layers are not visible beneath the dense forest canopy that covers most of the island, using current remote-sensing methods, very little is known about the extent of damage to the flora of these layers. Land-based surveys are thus urgently required to assess the condition of the flora and to control the introduced goats.
