ナショナルジオグラフィックさんのインスタグラム写真 - (ナショナルジオグラフィックInstagram)「Photo by @joelsartore / The European eel is one of a few species that spend most of their lives living in freshwater but journey to salt water in order to breed. They travel over 3,000 miles to the Sargasso Sea, making their migration one of the most impressive observed in the animal kingdom. The migration, while remarkable, leaves the species open to a number of threats, including predation, pollution, and fishing impacts. At one point, European eels were also caught as juveniles and farmed in the U.K. and other parts of Europe. The spread of this trade internationally is believed to have contributed to the decline in wild populations and ultimately to this species' endangered status. Photo taken at the Environmental Education Center of the Ribeiras de Gaia in Portugal. To see more species featured in the Photo Ark, follow me @joelsartore. #PhotoArk #savetogether」11月26日 20時38分