August 14, 2014 Survey at Tama River
Today, all members went to Tama-River to investigate the condition of the river. According to the weather report, it will rain in the afternoon, so we decided to the leave river before noon. We were on the side of the river where it’s close to Noborito station and we took some photos by using a waterproof camera. We were able to catch some fishes. Also, we asked few people about their opinion on foreign species.
While fishing, we caught Amur minnow and Freshwater minnow. We put those fishes into the handmade tank and took photos. Moreover, we identified different kinds of fishes such as carp, catfish, blue gill, black bass and mullet by merely looking at them. Most of them are foreign species and the reason why the amount of those species are increasing is because of water pollution. Usually native species are not strong enough to adapt their body to the change of the environment, as a result, the amount of the species decreases and it causes reproduction of the foreign species.
Fishermen at the river said that there is a pyramid of ecosystem that exists. The top of which was constructed by the foreign species while the native species made the bottom. They also said, once you release the animals, it causes a massive reproduction and it’s almost impossible to stop them, so let us please make sure to consider about our behavior.