About 2000 kinds of species which came from other countries currently live in Japan as invasive species. Invasive species are animals or plants which are non-native, and compete with the native inhabitants by taking over their territory. Due to close relationships between Japan and other countries, the entry of invasive species into Japan was made possible. The existence of invasive species also affected human beings, resources, and ecosystem.
The beetle is one good example of Japanese invasive species. The beetles’ population started a rapid growth is in 1999. They used to be not so popular before, however they gained popularity for two reasons. First, the International Plant Protection Convention, which came into effect in 1950 and restricted the import any harmful species in Japan, was relaxed. This made it easier to import animals and plants, so the number of species entering Japan increased. The other reason is that the image of beetles people had before changed dramatically because of the affection of children to foreign beetle. Surprisingly, this enthusiastic trend has extended to adults as well. Foreign beetles have characteristics that are different from the Japanese ones with respect to their size, shape, and color. For example, the Hercules beetle, which is a foreign beetle, is said to be the biggest beetle in the world. Its wing color is yellow, and it has a big horn. In addition, some TV animations about insects, especially beetles, were broadcasted in a way that gave an impetus to the popularity of non-native beetles from abroad. So the number of beetles imported from overseas to Japan as pets has increased year by year. In fact, the number of non-native beetles imported in 1999 is amounted to 7,000; reached 463,000 in 2000 eventually peaked at 1,923,000 in 2005. When we compare the ratio between 1999 and 2005, it is about 275 times. This exponential rise in reflects the increase in the number of people attracted to small insects.
As a result, many problems have occurred due to the foreign beetles. First, there are possibilities of any microbe and parasite carrying diseases. It is said that imported beetles haven’t brought any disease nor been harmful for human beings in Japan at present, but we can’t declare this will always be the same. Secondly, it could affect agriculture and environment. One of the invasive beetles, the Rhinoceros beetle, feeds on sugar canes, palm, and pineapple trees. And this feeding habit causes damages to farm products. Moreover, the invasive species usually don’t have natural enemies. That’s why their number has increased sharply, so it can be said that “wild invasive species” take away original environments from the native species. The most serious problem is genetic pollution by hybridization. Genetic pollution is undesirable gene flow into native populations. Spreading invasive species’ genes around domestic species has the danger to distinct native ones. Many scientists have had misgivings about the disappearance of native species in near future.
In 2004, Invasive Alien Species Act was enforced. This is the law to limit how many and what kinds of species can be imported into Japan. Although this law has taken effect for five years, we have faced to the issue of invasive species because of the difficulty in removing them. Practically, it has remained difficult to completely reduce the import of foreign insects.
Finally, we need to know the root of these serious problems about invasive species. The people have brought foreign species from other countries into Japan for several reasons such as pets, and also they have spread them over the country. In the beetles’ case, people who can’t breed foreign beetles anymore, they tend to release the non-native beetles into the wild. They do this because they think that it is the best way for living things even though this action has had a bad influence on the environment. We must not forget our responsibility for all of the species when we concern with them. Japan isn’t only the country that has the issue of these invasive species, this issue has happened in the countries of all over the world too. Nowadays, global warming, acid rain, rising sea level, and environment pollution are well-known as the world issues, and people have made an effort to change them for the better. On the other hand, there are still controversial issues like invasive species on the earth. It is necessary not only to think but also to put these ideas into action to protect all of living things before this problem is more serious.
