Tanzania has recorded a sharp decline of fish stocks in the Indian Ocean, blamed on the use of dynamite fishing(ダイナマイト漁)and overfishing. Recent reports from the Ministry of Livestock and Fisheries note that sea pirates have been fishing illegally in deep waters using dynamite. It is estimated that fish catches declined to at least 360,000 tonnes in 2016 from an average 390,000 tonnes over the past four years. Tanzania's total demand is 730,000 tonnes of fish per year. Local companies have now resorted to importing fish from China, with data showing that 2,000 tonnes of mackerel(鯖)fish from the Asian country enter Tanzania every month. (http://allafrica.com/stories/201712270164.html)