落ち鮎

今年はアユの遡上が近年になく多かったせいか、落ち鮎の数も大変多いようです。ことしはまた、夏の間の長雨で山々が水を含み、川の水量が落ちず、そのために水質が向上したようで、それも鮎の生育に好ましい結果をもたらしたのかも知れません。写真は桂離宮付近の河岸から水中に群れる鮎を撮影したものです。オイカワなどの他の魚より一段と大きく成長した鮎が、2匹連れだって、あるいは4，5匹が集団となって群れています。近くの浅瀬では鮎が跳ねる姿が頻繁に目撃できます。産卵行動が起きているのかもしれません。

This year, the number of Ayu running up the river was much higher than in recent years, and the number of Ayu that come down the stream seems to have been very high. This year, the mountains were saturated by the long rains during the summer, which kept the water flowing and improved the water quality, which may have had a favorable effect on the growth of Ayu. The photo was taken from the river bank near Katsura Imperial Palace, showing Ayu fish swarming in the water. Ayu fish are much larger than other fish such as Oikawa, a pale chub, (Zacco platypus) and they are swarming together or in groups of four or five. You can often see them jumping in the shallows nearby. They may be spawning.

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Photo 2021-10-15