For breeding little terns

Introduction ~ Message from the Nature Osaka

Our group has been investigating wildlife since 2019 in Yumeshima, the planned venue for the Kansai Expo. Among them, we are proposing environmental assessments from citizens.

 The man-made island of Yumeshima has been filled with incinerator ashes, dredged soil, and other waste materials over the years, but it is also a place where a vibrant wildlife is being created.

Unintentionally, various natural environments such as salt marshes, reed beds, freshwater ponds, grasslands, and gravel were born in Yumeshima. So,these sites attract a wide variety of wildlife and plants.As a result, we found biodiversity-rich habitats and endangered species.


There is no forest yet. However, as an artificial island located in the inner part of Osaka Bay surrounded by urban areas, Yumeshima is an indispensable place for migratory birds, such as sandpipers, plovers and ducks, to rest and  spend a period of time on the season.

What surprises me especially is, more than 5,000 the Common Pochard(Aythya ferina) visit the area. if we could count continuously every winter, this number is equivalent to that required to qualify as a Ramsar site. In addition, more than 100 the Common Shelduck(Tadorna tadorna)come to one of the ponds in Yumeshima. This species is endangered species (VU) Japan. However, the area of the pond, where rainwater has accumulated on the natural subsidence of the landfill, is gradually being reduced by the landfill work. This pond is now being reclaimed for the Expo, and we are not sure if it will be there next year.

Among the migratory birds, the Llittle Tern(Sterna Albifrons), is feared to be extinct.
They come to Japan only during the breeding season (from late April to early August) and breed in gravel land such as riverbeds and natural beaches.However, the number of such gravel lands is decreasing in Japan, and recently they have been using construction sites to breed.


In 2020, a large group of Little Tern  came to Yumeshima and started their breeding behavior. However, many workers without knowledge continued their works in the area and the little tern escaped from the area.

In order to protect the breeding of this endangered species, we cooperate with the Osaka Ports and Harbors Bureau in 2021. We expect the breeding of little terns.

The nature of Yumeshima is surprisingly rich, even though it is an artificial island in the city.This site introduces you to its richness.

And I sincerely hope that the Kansai Expo 2025, with its theme of "Shining Life," will be an Expo that values not only human beings but also this kind of natural biodiversity.

I want everyone to ask....

We are working with the Osaka Port Authority to protect the breeding of the little tern.

However, a large-scale fireworks event is being planned as a pre-event for the Kansai World Exposition in the Yumeshima breeding guidance area on May 4, when the terns are breeding.

The fireworks event should definitely be cancelled during the breeding period of the little tern.
Becouse if the little tern is startled, there is a great chance that it will 
abandon its nest and chicks and fly away.

We believe that this is inappropriate for the Expo, which is based on the SDGs and the theme of "Shining Life.
We are deeply concerned about the implementation of this event, and if it is forced to go ahead, we would like to issue an international statement against the event.


In Yumeshima, an important breeding ground for little terns
Urgent statement about upcoming large-scale event

March 3, 2021

Yoshihiro Natsuhara, Chairman of the Osaka Natural Environment Conservation Association

Koichi Endo, Chairman of the Wild Bird Society of Japan

Japan Wild Bird Society Osaka Branch Manager Mikio Matsuoka

Yumeshima, the planned site for the Osaka Kansai Expo, is an artificial island located in the northeastern part of Osaka Bay. For 40 years, dredged soil, incineration ash, industrial waste, etc. have been brought in to form land, but by chance a diverse ecosystem was born, and various migratory birds visited there every season. Endangered species have also been identified.

The Osaka Nature Conservation Association has been investigating creatures since 2018, but in April 2020, it was discovered that many endangered migratory bird little terns have come to Yumeshima, and many in the gravel area of ​​the 3rd ward. I confirmed that the pair was breeding.

Currently, reclamation work is underway at the Yumeshima whole island rapid pitch, and the breeding of little terns in 2020 failed due to the continuation of the work. After that, after repeated discussions with the Osaka Ports and Harbors and coordination of the construction plan, it was decided to secure a group breeding area for little terns in Yumeshima this season.


However, it was announced that a large fireworks event was planned for May 4th at this location.

Little terns are birds that are extremely sensitive to human entry into breeding grounds and flying objects in the sky. Therefore, from the end of April to the end of July during the breeding period, you should not hold events involving fireworks or drone flight in Yumeshima and the airspace over Yumeshima, and do not enter near the planned breeding site. ..

In Yumeshima, which has already secured a breeding ground since last year, breeding success should be the first priority, and the large-scale event currently planned for May 4 will be held by mid-April or The schedule should be changed after August.


(the reason)

1. 1. Little terns are migratory birds designated as Endangered Species by the Ministry of the Environment, and stay in Japan from the end of April to the beginning of August to breed and raise children. There are concerns about extinction internationally, and it is an international responsibility of Japan to protect Japan's breeding grounds.

2. 2. In Osaka, the number of natural rivers and coasts suitable for breeding little terns has decreased sharply, and little terns tend to choose construction sites such as the Kansai Airport construction site as breeding sites.

3. 3. In Yumeshima, the mass breeding of little terns has been confirmed even before 2020, and therefore, Yumeshima has been designated as an important A rank of biodiversity hotspot in Osaka Prefecture. The city of Osaka has also formulated a biodiversity strategy and has selected little terns as "creatures of note for protection."

4. The Ministry of the Environment's Guidelines for Conservation and Consideration of Little Tern Breeding Areas indicate that entry restrictions to areas where breeding is expected, and that after the start of breeding, do not enter the area and wait until the breeding ends will lead to conservation. ..

5. The Bird and Beast Conservation and Management Act prohibits damage to birds and beasts and bird eggs. Interfering with reproductive activity when eggs and chicks are found can violate the Wildlife Conservation Act. Events such as fireworks and drones, and people entering, should be avoided during the breeding season, as it is expected that the parent birds will abandon their eggs and chicks and flee.

6. The estimated number of reproductive behavior confirmed individuals in Yumeshima in 2020 is 500, and the number of individuals of this scale is the largest in Osaka Bay. In 2020, there are no reports of mass breeding of this scale elsewhere in Osaka Bay, and it is undeniable that there is no suitable breeding ground in Osaka Bay.

7. Osaka Prefecture, Osaka City, and the 2025 Japan International Exposition Basic Plan also carry SDGs, and there are items related to the conservation of living things and the environment, such as "to prevent the loss of biodiversity". Conflicting acts should be strictly discouraged.

that's all


(Supporting organizations as of noon on March 3 in the order of Aio) 

The Nature Conservation Society of Japan

The Nature Conservation Society of Japan Nature Observation Instructor Osaka Liaison Committee

Specified non-profit corporation Japan Bird Rescue Association

Meeting to protect the nature of Hatogamine

General Incorporated Association BirdLife International Tokyo

Certified NPO corporation Bird Research

Yamashina Institute for Ornithology



Osaka Nature Conservation Association: Flow of Little Tern Conservation Activities and Photograph Record of Little Tern in 2020


Ministry of the Environment ・ Guidelines for conservation and consideration of little tern breeding grounds


Cases of protection in the UK

News! Schedule postponement officially announced 

Everyone who cooperated with and supported the statement requesting a change in the schedule of the fireworks event in Yumeshima during the breeding period of little terns.

Thank you very much for this time.

On the official page of the fireworks event, the fact that it was decided to change the schedule from the originally scheduled May 4th and the reason for it were announced on the night of March 23rd.
The date after the change is still undecided.
There was no flashy press release, but this time it was only announced that it was postponed because it will affect the business plans of the surrounding area.

The postponement statement was posted last night at the top of this official page.
Yumeshima Super Fireworks

It seems that the changed schedule is currently scheduled for mid-August, but I heard that there are still some adjustments and the schedule could not be announced at the same time.
It took a long time from the notification of the change decision to the official announcement, and I was worried. However, since I have met with the event executive committee several times and have been able to respond in good faith, I think we can cooperate in planning for the future Expo from the standpoint of protecting the natural environment.

Currently, we are cooperating with the Osaka Ports and Harbors to improve the environment for the little tern breeding area, and we are also receiving a great deal of cooperation from the local contractor, Penta-Ocean Construction.
It's about nature, so I'm not sure, but I'd like to do everything I can to create a group colony in Yumeshima in May, and expect the great power of nature.
We look forward to your continued guidance and support.

March 24, 2021

ネイチャーおおさか 公益社団法人 大阪自然環境保全協会

ネイチャーおおさかは、身近な自然を愛し、これを守り育てたいと願う市民が運営している公益社団法人の自然保護団体です。お電話でのお問い合わせはこちら 06-6242-8720

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