Damage caused by feral goats feeding has become an environmental problem on Uotsuri Island in the Senkakus. A small population of goats was intentionally released on the island in 1978 by a private political entity and their numbers have exploded to an estimated count of at least 300. (Ref. 1)

As a result, a satellite imaging study of the damage caused by the Uotsuri Island goats is being conducted, in which high-resolution imagery from the satellites Ikonos (captured in 2000), QuickBird (captured in 2004 and 2006), and ALOS (captures in 2007) is compared with aerial photography of the area that was taken in 1978, before release of the goats. This study has shown that of the 3.8 square kilometers of Uotsuri Island's total land area, 13.59% is now bare ground, and landslides have become ubiquitous, with severe damage to forest and raised coral reef vegetation being identified. (Ref. 2)

Many endemic and biogeologically important species reside on Uotsuri Island, but there is concern that if this situation is allowed to continue, the severe impact on the ecology of the island could lead to the extinction of many valuable species. In March 2003, the 50th annual conference of the Ecological Society of Japan passed a resolution for an "Appeal for the Eradication of Introduced Goats on Uotsuri Island in the Senkaku Islands," submitting it to the Ministry of the Environment and the Ministry of Foreign Affairs. The Mammal Society of Japan and the Biological Society of Okinawa also passed similar resolutions in 2002 and 2003, respectively. (Ref. 1)

March 2001 "Memorandum on questions on the problem of feeding damage by the Uotsuri Island feral goats" (Ref. 3)

February 2012 "Memorandum on questions concerning landing on and effective control of the Senkaku Islands" (Ref. 4)

The council of Ishigaki City (chaired by Iritakenishi Hitoshi), which officially administers the Senkaku Islands under Japanese law, unanimously passed a "Resolution to request the capture of the goats in the Senkaku Islands (Uotsuri Island)" in March 2008. The council is requesting that the national government conduct an investigation of the situation on the island and undertake measures to protect the environment. (Ref. 5)

A Senkaku Islands field survey that was dispatched by the Tokyo Metropolitan Government in September 2012 (observations with 10x binoculars and the naked eye from small boats, within roughly 200 meters from the shoreline) also reported damage to Uotsuri Island's vegetation caused by feeding by feral goats. The report stated that no vegetation at all was observed atop the raised coral reefs, the former Livistona chinensis forest was now sparse grass, grasses had been lost from the cliff area and soil had been sliding there, the land around the former katsuobushi (dried bonito fish flakes) factory was nearly barren, and the advancement of erosion of surface earth had been observed, and that these were all likely the result of extreme foraging by the feral goats. (Ref. 6)

The overall effects of the feral goats on the biota of Uotsuri Island are summarized and discussed in detail in Yokohata Yasushi, Yokota Masatsugu, and Ota Hidetoshi, "The problem of feral goats and the biota of Uotsuri Island in the Senkaku Islands," Institute for Peace Science, Hiroshima University (2009). (Ref. 7)

Ref.1　：Yokohata Yasushi, "Senkaku Shoto Uotsurijima no yaseika yagi to sono taisaku o motomeru yobosho ni tsuite" (The Problem of Feral Goats on Uotsuri Island in the Senkaku Islands and Appeals for Countermeasures to Resolve the Problem), Japanese Journal of Conservation Ecology 8, no. 1 (August 2003), pp. 87-96.

Ref.2　：Yokohata Yasushi, Kaneko Masami, Yokota Masatsugu, and Hoshino Buho, "Kokaizodo eisei gazo o mochiita Senkaku Shoto Uotsurijima no yagi ni yoru seitaikei henka no tsuiseki" (Surveillance of Ecosystem Change Caused by Goats on Uotsuri Island in the Senkaku Islands, Using High Resolution Satellite Images), National Institute of Informatics KAKEN Database of Grants-in-Aid for Scientific Research (Scientific Research [C] in the Field of Environmental Policy and Environmental Impact Assessment, 2007-8), Final Research Report.

Ref.3　："Memorandum on questions on the problem of feeding damage by the Uotsuri Island feral goats," Question no. 36, submitted on March 1, 2001, House of Representatives website.

Ref.4　： "Memorandum on questions concerning landing on and effective control of the Senkaku Islands," Question no. 48, submitted on February 7, 2011, House of Councillors website.

Ref.5　："Resolution to request the capture of the goats in the Senkaku Islands (Uotsuri Island)," resolved on March 24, 2008, Ishigaki City Council website.

Ref.6　：Ogi Haruo and Yamada Yoshihiko, Tokyo Metropolitan Government The Senkaku Islands Field Survey Report (October 2012).

Ref.7　：Yokohata Yasushi, Yokota Masatsugu, and Ota Hidetoshi, "Senkaku Shoto Uotsuri Island no Seibutsuso to yaseika yagi mondai" (The problem of feral goats and the biota of Uotsuri Island in the Senkaku Islands), IPSHU Research Series 42 (Institute for Peace Science, Hiroshima University, 2009), pp. 307-326.

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