Resolution To Request For Protection Of Dugongs In Okinawa Prefecture
Dugongs are large sized harbivore mammals living in the tropical coral reefs which range from the coast of Eastern Africa to South-Eastern Asia and Oceania waters. Due to capturing for meat, unintentional catching by fishing net and development of the coastal areas, the population of dugongs is decreasing and their habitats are getting disconnected. Judging that the species survival is being threatened, the International Union for Conservation of Nature (IUCN) decided, in 1996, to apply its new criteria and classified dugongs as being vulnerable of extinction (VU A1cd).
The south-western Islands of Japan constitutes the northern boundary of the dugongs’ habitat. As it seems to be hopeless to find dugongs around Taiwan, dugongs surviving in the Okinawa waters are specially valuable not only because they contribute to the biodiversity of Japanese fauna but also as their habitat adds to the global diversity of the ecosystems in which they live. The World Wide Fund for Nature (WWF) chose the ecosystem of the
south-western Islands as one of the ‘Global 200’ sites to be preserved.
The Mammalogical Society of Japan classified, in 1997, the Japanese dugongs as being critically endangered based on the estimation of the number of their adults to be less than fifty.
Dugongs lived in the south-western Islands waters since the prehistoric ages. According to the record in the Meiji era (late 19th century) they used to be commonly seen to the south of the Amami Oshima Island. Their population and the habitat gradually decreased until now they face the threat of extinction. A group of researchers has started, since 1997, to study the state of dugongs in Okinawa. They could not find any of them around the Sakishima Shoto Islands. Since 1970, the occasional capturing,
stranding and sighting of them have been recorded only around the Okinawa Islands. The year round sighting of dugongs is limited within the 52km range of waters between the Katsuren Peninsula and Ibu of the Eastern Okinawa Island. This area is the last remaining habitat of dugongs around the south-western Islands.
The need to protect dugongs has been pointed out since the 1930’s. In 1955, the Ryukyu Government of Okinawa, then under the US jurisdiction, designated the species as an ‘Natural Monument’ (Natural Treasure). After Okinawa was returned to Japan, the Japanese Government also designated, in 1972, the species as an ‘Natural Monument’. In 1993, capturing of dugong
was principally prohibited according to the Aquatic Resource Protection Law. These measures, however, have been effective only to prevent deliberate killing of dugongs but not strong enough to stop unintentional killing or to preserve their habitats. Although the use of the fishing net within the dugongs’ habitat is less frequent than in other areas, nine out of ten accidents of dugongs being stranded and killed in gill nets or trap nets around the south-western Islands, since 1970, have happened in this area. Unless we can stop this kind of human caused death of dugongs and begin to preserve their habitats and restore their population it is highly probable that they would disappear from our shores.
Noting the above situation, and wishing to protect the remaining small local population of dugongs in Okinawa Prefecture, and also hoping to restore their population to a sound level, we, the Mammalogical Society of Japan request the Environment Agency, Agency for Cultural Affairs, Fishery Agency, Defense Facilities Administration and other related offices of the Japanese Government and the Okinawa Prefecture the following:
1) To designate the water area between the Katsuren Peninsula and Ibu, not deeper than 90 meter, as the dugongs’ habitat and take an emergent measure to prohibit, within this area, the use of fishing tools such as gill nets and trap nets which have caused many death of dugongs; special consideration for the welfare of the fishermen should also be made;
2) Not to allow any new exploitation of the above water area or new construction activity unless such activities are proved to be harmless to dugongs and their habitats;
3) To reassess the human activities within the above area such as fishing without using gill nets or trap nets or military drill from the view point of protection of dugongs so that harmful activities would be discontinued;
4) To draw up a long term plan for restoring the population of dugongs and for preserving the coral reef ecosystem and promote the type of fishery in harmony with these objectives; to organize specialists for these purposes.
The Mammalogical Society of Japan
(Translated by Iyanaga Kenichi：ａmember of the Association To Save The Dugongs Of The Northern-most Habitat )