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  Request for Protection of the Dugong
by Japan Federation of Bar Associations

   [ Japanase ]


Request for Protection of the Dugong

July 14, 2000

Japan Federation of Bar Associations

Main Points

1. The Fisheries Agency, Environment Agency, and Okinawa Prefecture should singly or in cooperation immediately conduct studies on the ecology of the dugongs living throughout the Nansei Islands (below, "dugongs"), and, based on the results, immediately formulate and implement effective and appropriate protection measures that are adequate to head off the dugong's crisis of extinction.

2. In the event that the Defense Facilities Administration Agency and Okinawa Prefecture plan a substitute facility for Futenma Air Station at Nago City's Henoko coastal region, they should immediately perform an environmental impact assessment on the impact of that plan on the dugongs there.

Reasons for Request

Since March 2000 we have conducted a study that included talking with Okinawa Prefecture, Nago City, local citizens' groups, ministries and agencies of the central government, dugong researchers, environmental organizations such as WWF-Japan, and other people and organizations, and we have reviewed the current system for dugong protection. We are submitting this Request to ask that the involved institutions take effective steps to protect the dugong.

I. Dugong Ecology

The dugong is a marine mammal belonging to the order Sirenia, family Dugongidae, which in large individuals attains a length of 3 meters and a weight of 420 kg. Its habitat ranges across the Indian Ocean and the tropical and subtropical Pacific Ocean. There are said to be 100,000 individuals at present, although definite figures are lacking. In Japan, the presence of a few dugongs has been confirmed off the east coast of Okinawa Island, and this area is the northern limit of the dugong's habitat.
Little is known about the dugong's ecology. Research during recent years by a group headed by Professor Toshio Kasuya of Mie University has found: (1) a few dugongs live along the eastern cost of Okinawa Island from the Katuren Peninsula north to Ibe; (2) during the day they live from the outer edges of coral reefs out to depths of 85 meters, while at night they feed in shallow depths of several meters in coral lagoons; and (3) seven kinds of seaweed (including Ryukyu-Amamo - Cymodocea serrulata - ) are distributed throughout this area, and dugongs feed on all of them, although data reveal no preferences. As the conditions for the animal's habitat the group cites: (1) feeding grounds with large amounts of seaweed; (2) places to rest during the day; and (3) corridors through which to move between feeding grounds and resting places.

II. The Dugong Is Endangered

In the past the dugong was known to exist throughout the whole Nansei Islands chain. In particular, in the Yaeyama Islands at the southern terminus of this chain, there were places where dugongs were required as an annual tribute in the feudal age prior to 1868. As such, the Yaeyama Islands are thought to have been the primary area of Japan's dugong distribution.
However, surveys by Professor Kasuya's group found no dugongs at all in the Yaeyama Islands at present. Although large seaweed communities suitable as dugong feeding grounds have been found in that area, it is speculated that the intensive coastal fishing operations using fixed shore nets and gill nets have deprived the dugongs of the corridors they need to move between feeding grounds and resting places, thereby making it impossible for them to live in this area. At this time the group has found dugongs living only off the eastern coast of Okinawa Island, and speculates that there is little possibility of finding dugongs in any other area of the Nansei Islands. The group also thinks that only a very few dugongs live near Okinawa Island. It is thought that this decline in dugong numbers is due to human activity such as the captures carried out from long ago, and by-catching in fixed shore nets and gill nets.
The following conclusions can be drawn from the foregoing: (1) The dugong habitat off Okinawa Island is the last in Japan; (2) from a worldwide perspective, these dugongs are of great value as the northernmost population; and (3) this population is very small and in danger of extinction.

III. Current Measures for Dugong Protection Are Ineffective

1. An Overview of Current Protection Measures
Of the designations "extinct species," "extinct in the wild," "critically endangered species," and "lower risk species" the Red List of the World Conservation Union (IUCN) gives the dugong the designation "endangered species," and among endangered species it is classified a "vulnerable species" (a species that faces a high risk of extinction in the wild in the medium-term future). In many places of the world capturing the animal is prohibited.
Under the Convention on International Trade in Endangered Species of Flora and Fauna (CITES), the dugong is listed in Appendix I, which affords the most rigorous control. The exception is the dugong's healthy Australian population, which is listed in Appendix II.
Because Japan's dugongs in the Nansei Islands (Ryukyu Archipelago) are judged by the Mammalogical Society of Japan to number fewer than 50 individuals, the society has assigned its designation "endangered species," which corresponds to the IUCN's category of "endangered species" (a species in crisis that will with a high probability become extinct in the wild in the near future).
Before WWII the dugongs in the Nansei Islands were "government-designated natural monuments" under the Historic and Scenic Area and Natural Monument Preservation Law. In the postwar years the animal became "a natural monument designed by the Ryukyu government" in 1955 prior to Okinawa's reversion to Japan, and in 1972, when Okinawa returned to Japanese control, the animal became a "nationally designated natural monument" under the Cultural Properties Law. However, even though the dugong is designated a natural monument, such a designation is only effective in prohibiting the capture of species for which geographical regions are not designated.
The Fisheries Agency's "Data Book of Rare Japanese Aquatic Animals" lists the dugong as an "endangered species," while the "Basic Policy on the Protection of Wild Marine Plants and Animals" (Ministry of Agriculture, Forestry and Fisheries directive no. 293) lists it under wild marine plants and animals that require protection. The Law for Conservation of Aquatic Resources and its enforcement rules prohibit the dugong's capture, but the government has not instituted any protection measures that are more aggressive. And although the dugong suffers harm as bycatch in fixed shore nets and other nets, the Fisheries Agency indicates its opposition to restricting nets because that would run counter to promotion of the fishing industry.
Japan's Law for the Conservation of Endangered Species of Wild Fauna and Flora (LCES) designates the dugong an internationally rare wild species, which prohibits display, transfer, and other acts without registration, but the animal is not designated a domestically rare wild species, and no measures for more aggressive protection under the law have been enacted.

2. Protection Measures Demanded by the Convention on Biological Diversity and Domestic Environmental Law
The Biodiversity Convention is meant for the maintenance and recovery of populations of species in their natural habitats, and as a means to accomplish that, it specifies that measures be taken to designate and manage protected areas, and to recover habitats. In response to this, Japan's national biodiversity strategy also sets forth "preventing the danger of plant and animal extinctions" as one of its goals for the time being, and it notes the need for the "designation and management of protected areas" and the "protection and management of wildlife."
The Basic Environment Law sets forth "To protect the biodiversity such as the diversity of ecosystems and wildlife species, and to orderly conserve the various features of natural environment such as in the forest, farmlands and waterside areas in accordance with the natural and social conditions of the area" (Article 14.2) as one of its guidelines for policy measure formulation, while the LCES stipulates the designation of rare wildlife species in Japan (Article 4.3) and the regulation of capture and other activities (Article 9), and, when necessary, makes it possible to designate habitat and other places as protected areas, and restrict actions within protected areas (Article 36 ff.).
In view of these recent legal institutions meant for biodiversity, Japan must not only enact steps prohibiting the capture of dugongs, but also institute more effective protection measures because the endangered dugongs in the Nansei Islands are the species' northernmost population, as well as Japan's only dugong population. And yet, at present no attempts are being made to consider ways of actively protecting dugongs. Even the government agencies responsible for its protection, including the Fisheries Agency and Environment Agency, make no attempt to study its ecology, and they have expressed the view that it will be difficult even to designate the dugong as a rare wildlife species within Japan in accordance with the government's own law, the LCES.
No basic study of the dugong's ecology has ever been performed, and no one has accurately determined its ecology, its numbers, or even its habitat range. Meanwhile, researchers and others are vigorously pointing out that the animal is endangered. Because fewer than 50 dugongs are said to live in the Nansei Islands, there is no guarantee that extinction can be averted even if all possible protection measures are taken. Japan's government not only invokes no active measures to protect such a rare animal within Japan, but also does not even attempt to study its ecology. Such a lack of action is in clear violation of the purposes of the Biodiversity Convention and its related domestic law, and Japan is sure to endure international criticism because of that lack.

IV Dugong Protection Is Needed Immediately

1. An Immediate Study of the Dugong's Ecology, and Formulation of Drastic Measures to Protect Its Habitat
As stated above, current dugong protection measures merely prohibit capturing individuals, and include no measures at all for conserving dugong habitat. Protection of its habitat is therefore inadequate. Protecting the dugong will require immediately studying its ecology and enacting effective protection measures, including those to conserve its habitat.

2. Fixed Shore Net and Gill Net Fishing Restrictions, and Compensation to Fishermen
Since 1979 there have been nine instances of dugong bycatches in Okinawa Prefecture; three were in gill nets, and six were in fixed shore nets. The aforementioned study by Professor Kasuya's group emphasizes the need to restrict fishing by saying, "With a small population like that of Okinawa's dugongs, even accidental deaths on the order of once in two years as recorded heretofore can have serious consequences. It is desirable to avoid the use of gill nets and fixed shore nets in areas inhabited by dugongs."
If fishing is to be restricted, the problem of compensation for fishermen is unavoidable, but a solution would seem to be within the realm of possibility because the number of fishermen in that area is likely small.
Even if prohibiting fishing is impossible, measures to prevent dugong bycatches by modifying net structure, changing locations, or other means should be considered.
Further, a seaweed called "mozuku" is farmed in many places throughout this area. There are no records of dugongs being caught in mozuku nets, but as they are located in dugong feeding grounds, it will be necessary to consider changing mozuku net locations, or other measures.

3. EIA for Plan to Build a Replacement for Futenma Air Station

(1) The Plan for a Facility to Replace Futenma Air Station
The Defense Facilities Administration Agency plans to build a facility at Nago City's Henoko coastal region in Okinawa as a substitute for Futenma Air Station when the land is returned. According to the "basic proposal for a sea-based heliport" that was set forth as the general idea for this replacement facility on the occasion of the 1997 Nago City referendum, this facility would be built off shore by reclaiming public waters off the coast at Henoko, and would either be supported on piers or pontoons. It would be 1,500 meters long, 600 meters wide, have a 1,300-m runway, and be removable. It would be comparable to Futenma in the types and number (60) of U.S. military aircraft deployed.
Since 1997 making the planned facility into an airfield for joint civilian and military use has been considered in accordance with a proposal by Okinawa Prefecture's governor. The details of this joint airfield plan, such as size and construction method, are not yet known, but there is no mistaking that it would require the reclamation of a larger sea area than the "basic proposal for a sea-based heliport."
Anticipated environmental impacts of constructing this facility include noise, pollution of the environment by air pollutants and weapon accidents, reduction and disappearance of coral reefs, mangrove forests, and seaweed beds, and serious impacts affecting the survival of the dugongs living off the eastern coast of Okinawa Island.

(2) Need for an EIA When Developing the Construction Plan
As noted above, as yet no detailed information is available on the location, size, makeup, or construction method of the plan for building a facility to replace Futenma Air Station. Further, if the idea under consideration for making the project into a joint military/civilian airfield becomes a reality, it will be a large-scale project that exceeds the planned size under the previously submitted basic proposal for a sea-based military heliport, which would further augment the environmental impact caused by construction.
Construction of an airfield offshore from Henoko, which would necessitate reclaiming a large public water area, is anticipated to impact severely on the dugong's habitat as described below. In particular, the proposed offshore construction site is located in the center of the presently confirmed dugong habitat off the eastern coast of Okinawa Island, which means that airfield construction would split the habitat. This could well be a fatal impediment to the continued existence of the local dugong population.

a) Contraction and Disappearance of Seaweed Beds Serving as Feeding Grounds Reclamation and placing structures under water will not only directly destroy seaweed beds, but also impact severely on the local marine ecosystem, which has maintained a balance until now, by changing the tidal currents that arise there. The contraction and disappearance of seaweed beds are therefore expected. It is conjectured that seaweed beds in the construction site are important dugong feeding grounds, making it possible that contraction and disappearance could impact heavily on the dugongs.
Further, even if the substitute facility is built entirely on land, the sediment and red soil runoff into the sea anticipated during or after construction could reduce or eliminate seaweed beds (in many places throughout Okinawa Prefecture, red soil runoff into the sea due to construction and other causes has killed coral and disrupted marine ecosystems).

b) Noise Impact
The dugong is a very cautious animal and sensitive to sounds. As the present Futenma Air Station produces intense noise, it is expected that construction and operation of the planned replacement facility will expose the area to a level of noise roughly equal to that at Futenma. It is quite possible that such noise will affect the ecology of the dugongs in that area.

c) Other Impacts
Even now in the Henoko coastal area the U.S. Marines conduct landing exercises with amphibious vehicles, and it has been observed that the resulting noise and seaweed bed destruction affect the dugongs. If such exercises are expanded and reinforced by the operation of this replacement facility, it is possible the dugongs will be subjected to still greater impacts. In addition, there will also be increased dangers of aircraft accidents, and other accidents such as fuel spills from base facilities.

Thus, in view of the dugong's crisis situation as described above, steps are needed to avoid impacts on the animal. In the event that the Defense Facilities Administration plans to build a facility off the coast at Henoko, Nago City, to replace Futenma Air Station, then it should at the initial planning stage initiate procedures for an environmental impact assessment in order to investigate the extent to which facility construction will affect the dugong's ecology. Further, if the facility is planned as a joint civilian/military airfield, then Okinawa Prefecture, which would be the project executor, should carry out similar EIA procedures jointly with the Defense Facilities Administration.

Request for Protection of the Dugong (Summary)

Main Points

1. The Fisheries Agency, Environment Agency, and Okinawa Prefecture should immediately conduct studies on the ecology of the dugongs living throughout the Nansei Islands (below, "dugongs"), and, based on the results, immediately formulate and implement effective and appropriate protection measures that are adequate to head off the dugong's extinction crisis.

2. In the event that the Defense Facilities Administration Agency and Okinawa Prefecture plan a substitute facility for Futenma Air Station at Nago City's Henoko coastal region, they should immediately perform an environmental impact assessment on the impact of that plan on the dugongs there.

Reasons for Request

1. A recent study by a group of researchers found that the dugong, which in the past inhabited the entire Nansei Islands region, now barely exists off the eastern coast of Okinawa Island, and estimated that the local population has such a small number of individuals that its continued existence is in jeopardy; and that intermittent dugong deaths occur due to bycatches of individuals in fixed shore nets and gill nets along the coast. Further, there is a plan to build a facility to replace Futenma Air Station when that station's land is returned to Japanese control, and the planned site is the area offshore from Henoko, Nago City in Okinawa Prefecture, an area that is believed to be critical dugong habitat. For these and other reasons, we have determined that the continued existence of the local population of dugongs inhabiting that area faces a serious survival crisis as a species.

2. Accordingly, effective dugong protection measures must be immediately implemented to preserve the species (local population). However, current protection measures are not necessarily considered adequate; in fact the involved government agencies maintain an extremely negative attitude about enacting further protection measures, and make no attempts even to study the animal's ecology. Those agencies cannot avoid being seen as twiddling their thumbs as this local dugong population heads toward extinction. This is quite intolerable, as it flies in the face of Japan's Law for the Conservation of Endangered Species of Wild Fauna and Flora and other laws and regulations meant to conserve biodiversity.

3. We therefore ask that the following actions be immediately taken to protect the dugongs.
(1) Formulate drastic protection measures including an immediate study of dugong ecology and protection of habitat.
(2) Restrictions on fishing with fixed shore nets and gill nets, and compensation for fishermen.
(3) An environmental impact assessment at the initial stage of planning for construction of a facility to replace Futenma Air Station.

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