It is an international convention that countries protect migratory birds, which moves from on country to another, by international cooperations. However, major tidelands are now disappearing. According to the Environment agency in Japan, 4.07 million hectare of tidelands has disappeared for 13 since 1992. In winter, rare migratory birds had visited this tidelands. It disappeared by a reclamation works of the government, and it costed 237 billion yen.
Some people think that it is necessary to the extinction of some ecosystems.
However, they don't realize that it is same as the extinction of human beings. Although a destruction is caused within the limits of one ecosystem, human beings are affected in some way through a food chain. After the smallest microorganisms disappear, small fish that ate those plankton disappear. Next, fish and birds disapear. At last, we, human beings, face the food shortage and health problems.